DIAGNOSIS AND TREATMENT OF HEART FAILURE

BACKGROUND

The sarcoplasmic reticulum (SR) is a structure in cells that functions, among other things, as a specialized intracellular calcium (Ca ²⁺ ) store. Ryanodine receptors (RyRs) are channels in the SR that open and close to regulate the release of Ca ²⁺ from the SR into the intracellular cytoplasm of the cell. Release of Ca ²⁺ into the cytoplasm from the SR increases cytoplasmic Ca ²⁺ concentration. Open probability of RyRs refers to the likelihood that a RyR is open at any given mffoczoment, and therefore capable of releasing Ca ²⁺ into the cytoplasm from the SR. Three RyR isoforms are known. RyR1 is the predominant isoform expressed in mammalian skeletal muscle, RyR2 is predominantly found in cardiac muscle, whereas RyR3 expression is low in skeletal muscle.

Mutations in RYR1 or RYR2 are characterized by inappropriate channel opening not related to contraction signals. This channel opening is further exacerbated by post-translational modifications such as PKA-phosphorylation, oxidation, or nitrosylation of the RyR channel. Leaky RyR is also implicated in disorders with wild-type RyR through post-translational modifications. This results in leaky channels, which exhibit a pathologic increase in the open probability under resting conditions. The SR Ca ²⁺ leak leads to a reduction in SR Ca ²⁺ content, with less Ca ²⁺ available for release and consequently weaker muscle contractions.

INCORPORATION BY REFERENCE

All publications, patents, and patent applications mentioned in this specification arc herein incorporated by reference to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference.

SUMMARY

In some embodiments, a method of treating a subject with a Ryanodine Receptor calcium channel modulator is disclosed. The method comprises determining if the subject has heart failure characterized by (a) a premature ventricular contraction (PVC) burden of at least about 5% of all heartbeats within a time period, wherein the PVC initiates after end of a T-wave of a preceding heartbeat; and (b) a heart rate preceding the PVC of at least about 60 beats per minute. The method comprises administering a therapeutically effective amount of the Ryanodine Receptor calcium channel modulator to the subject. In some embodiments, the Ryanodine Receptor calcium channel modulator is a compound of formula (1).

In some embodiments, a method of identifying a subject for treatment with a Ryanodine Receptor calcium channel modulator is disclosed. The method comprises determining if the subject has heart failure, wherein the heart failure is characterized by (a) a premature ventricular contraction (PVC) burden of at least about 5% of all heartbeats within a time period, wherein the PVC initiates at least about 100 msec after end of a T-wave of a preceding heartbeat; and (b) a heart rate preceding the PVC of at least about 60 beats per minute.

In some embodiments, the PVC initiates at least about 100 msec after end of a T-wave of a preceding heartbeat.

In some embodiments, the PVC burden ranges from about 5% of all heartbeats to about 20% of all heartbeats within a time period. In some embodiments, the PVC burden is at least about 10% of all heartbeats within a time period. In some embodiments, the time period ranges from about 60 seconds (1 minute) to about 24 hours, or any period of time in-between. In some embodiments, the time period is 60 seconds. In some embodiments, the time period is 24 hours. In some embodiments, the time period is 1 year.

In some embodiments, the heart rate preceding the PVC is at least about 70 beats per minute. In some embodiments, the subject has an ejection fraction less than about 40%. In some embodiments, the heart failure is further characterized by an N-terminal pro-b-type natriuretic peptide test greater than about 1 ,000 pg/mL. In some embodiments, the subject has an ejection fraction less than about 40%. In some embodiments, the heart failure is further characterized by an N-terminal pro-b-type natriuretic peptide test greater than about 600 pg/mL. In some embodiments, the heart failure is further characterized by an N-terminal pro-b-type natriuretic peptide test greater than about 1500 pg/mL.

In some embodiments, the subject has PVCs having at least two distinct morphologies. In some embodiments, the morphologies are different from each other. In some embodiments, the PVCs are not unifocal. In some embodiments, the PVCs are multi-focal. In some embodiments, the PVCs originate from the same foci (i.e., a single location). In other embodiments, the PVCs originate from different foci (i.e., more than one location). In some embodiments, the treatment of the subject decreases the number of PVCs. In some embodiments, the treatment of the subject decreases PVCs by greater than about fifty percent (50%). In some embodiments, the treatment of the subject decreases PVCs by greater than about eighty percent (80%).

In some embodiments, the treatment of the subject improves left ventricular' function, e.g., ejection fraction. In some embodiments, the treatment of the subject decreases the level of N- terminal pro-b-type natriuretic peptide (NT -proBNP).

In some embodiments, the treatment of the subject decreases at least one adverse cardiac adverse event in the subject. In some embodiments, the adverse cardiac event is ventricular arrhythmia. In some embodiments, the adverse cardiac event results in death. In some embodiments, the adverse cardiac event is cardiac arrest. In some embodiments, the treatment reduces the likelihood of death in the subject.

In some embodiments, the PVC is triggered by a delayed after depolarization (DAD), wherein the DAD results from a leak of Ca ⁺² from RyR2. In some embodiments, the leak is a diastolic Ca ⁺² leak. In some embodiments, the RyR2 is a post-translationally modified RyR2. In some embodiments, the RyR2 post-translational modification is at least one of nitro sylation, oxidation or phosphorylation.

In some embodiments, the calcium channel modulator is represented by the following structure: wherein R is COOH, or a pharmaceutically-acceptable salt thereof. In some embodiments, the calcium channel modulator is in the form of a salt with a pharmaceutically-acceptable acid or base. In some embodiments, the salt is selected from the group consisting of hemifumarate, sodium, potassium, magnesium, hydrochloride and hydrobromide. In some embodiments, the salt is a sodium salt. In some embodiments, the salt is a hemifumarate salt.

In some embodiments, and the calcium channel modulator is represented by the following structure: or pharmaceutically-acceptable salts thereof. In some embodiments, the salt is a hemi-fumarate salt.

In some embodiments, the calcium channel modulator is represented by the following structure: wherein, n is 0, 1, or 2; q is 0, 1, 2, 3, or 4; each R is independently acyl, -O-acyl, alkyl, alkoxyl, alkylamino, alkylarylamino, alkylthio, cycloalkyl, alkylaryl, aryl, heteroaryl, heterocyclyl, heterocyclylalkyl, alkenyl, alkynyl, arylthio, arylamino, heteroarylthio, or hetero arylamino, each of which is independently substituted or unsubstituted; or halogen, -OH, -NH ₂ , -NO ₂ , -CN. -CF ₃ , -OCF ₃ , -N ₃ , -SO ₃ H, - S(=O) ₂ alkyl, -S(=O)alkyl, or -OS(=O) ₂ CF ₃ ;

R ¹ is alkyl, alkenyl, aryl, alkylaryl, cycloalkyl, heteroaryl, or heterocyclyl, each of which is independently substituted or unsubstituted; or H;

R ² is alkyl, aryl, alkylaryl, heteroaryl, cycloalkyl, cycloalkylalkyl, or heterocyclyl, each of which is independently substituted or unsubstituted; or H, -C(=O)R ⁵ , -C(=S)R ⁶ , -SO ₂ R ⁷ , - P(=O)R ⁸ R ⁹ , or -(CH ₂ ) _m -R ¹⁰ ;

R ³ is acyl, -O-acyl, alkyl, alkenyl, aryl, alkylaryl, cycloalkyl, heteroaryl, or heterocyclyl, each of which is independently substituted or substituted; or H, -CO ₂ Y, or -C(=O)NHY;

Y is alkyl, aryl, alkylaryl, cycloalkyl, heteroaryl, or heterocyclyl, each of which is independently substituted or unsubstituted; or H; R ⁴ is alkyl, alkenyl, aryl, alkylaryl, cycloalkyl, heteroaryl, or heterocyclyl, each of which is independently substituted or unsubstituted; or H; each R ⁵ is acyl, alkyl, alkenyl, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or -NR ¹⁵ R ¹⁶ , -(CH ₂ ) _t NR ¹⁵ R ¹⁶ . -NHNR ¹⁵ R ¹⁶ , -NHOH, -OR ¹⁵ . - C(=O)NHNR ¹⁵ R ¹⁶ , -CO ₂ R ¹⁵ , -C(=O)NR ¹⁵ R ¹⁶ , or -CH ₂ X; each R ⁶ is acyl, alkenyl, alkyl, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or -OR ¹⁵ , -NHNR ¹⁵ R ¹⁶ , -NHOH, -NR ¹⁵ R ¹⁶ , or -CH ₂ X; each R ⁷ is alkyl, alkenyl, alkynyl, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or -OR ¹⁵ , -NR ¹⁵ R ¹⁶ , -NHNR ¹⁵ R ¹⁶ , -NHOH, or -CH ₂ X; each R ⁸ and R ⁹ are each independently acyl, alkenyl, alkoxyl, alkyl, alkylamino, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or OH; each R ¹⁰ is -NR ¹⁵ R ¹⁶ , OH. -SO ₂ R ⁿ , -NHSO ₂ R ⁿ , -C(=O)(R ¹² ). -NHC=O(R ¹² ), -OC=O(R ¹² ), or -P(=O)R ¹³ R ¹⁴ ; each R ¹¹ , R ¹² , R ¹³ , and R ¹⁴ is independently acyl, alkenyl, alkoxyl, alkyl, alkylamino, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or H, OH, NH ₂ , -NHNH ₂ , or -NHOH; each X is independently halogen, -CN. -CO ₂ R ¹⁵ , -C(=O)NR ¹⁵ R ¹⁶ , -NR ¹⁵ R ¹⁶ , -OR ¹⁵ , -SO ₂ R ⁷ , or -P(=O)R ⁸ R ⁹ ; and each R ¹⁵ and R ¹⁶ is independently acyl, alkenyl, alkoxyl, OH, NH ₂ , alkyl, alkylamino, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted, or H; or R ¹⁵ and R ¹⁶ together with the N to which R ¹⁵ and R ¹⁶ are bonded form a heterocycle that is substituted or unsubstituted; t is 1, 2, 3, 4, 5, or 6; m is 1, 2, 3, or 4; or a pharmaceutically-acceptable salt thereof.

In some embodiments, the calcium channel modulator is represented by the following structure: wherein: each R is independently acyl, -O-acyl, alkyl, alkoxyl, alkylamino, alkylarylamino, alkylthio, cycloalkyl, alkylaryl, aryl, heteroaryl, heterocyclyl, heterocyclylalkyl, alkenyl, alkynyl, arylthio, arylamino, heteroarylthio, or heteroarylamino, each of which is independently substituted or unsubstituted; or halogen, -OH, -NH ₂ , -NO ₂ , -CN, -CF ₃ , - OCF ₃ , -N ₃ , -SO ₃ H, -S(=O) ₂ alkyl, -S(=O)alkyl, or -OS(=O) ₂ CF ₃ ;

R ¹⁸ is alkyl, aryl, cycloalkyl, or heterocyclyl, each of which is independently substituted or unsubstituted; or -NR ¹⁵ R ¹⁶ , -C(=O)NR ¹⁵ R ¹⁶ , (C=O)OR ¹⁵ , or -OR ¹⁵ ; q is 0, 1, 2, 3, or 4; p is 1 , 2, 3, 4, 5, 6, 7, 8 9, or 10; and n is 0, 1, or 2, or a pharmaceutically-acceptable salt thereof.

In some embodiments, the calcium channel modulator is represented by the following structure: or a pharmaceutically-acceptable salt thereof, wherein each R ^1a , R ^1b , R ^1c , and R ^1d is independently alkyl, haloalkyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heteroaryl, heterocyclyl, -CN, -NO ₂ , -N ₃ , -NR ³ R ⁴ , -OR ⁵ , -SO ₃ H, - SO ₂ R ⁶ , -OSO ₂ R ⁶ , -S(O)R ⁶ , or -SR ⁷ , each of which is independently substituted or unsubstituted, or hydrogen or halogen,

R ² is alkyl, haloalkyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heteroaryl, heterocyclyl, -C(O)NR ³ R ⁴ , -C(O)C(O)NR ³ R ⁴ , -C(O)R ⁸ , -C(O)OR ⁸ , or -C(O)C(O)OR ⁸ , each of which is independently substituted or unsubstituted, each R ³ and R ⁴ is independently alkyl, haloalkyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heteroaryl, or heterocyclyl, each of which is independently substituted or unsubstituted, or hydrogen or halogen; or R ³ and R ⁴ together with the nitrogen atom to which R ³ and R ⁴ are attached form a heterocyclic or heteroaromatic ring, which is unsubstituted or substituted, and each R ⁵ , R ⁶ , R ⁷ , and R ⁸ is independently alkyl, haloalkyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heteroaryl, or heterocyclyl, each of which is independently substituted or unsubstituted, or hydrogen or halogen.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1: Treatment of rat cardiomyocytes with Compound (1) reduces calcium sparks after myocardial infarction.

FIG. 2: Treatment of rat cardiomyocytes with Compound (1) reduces calcium sparks after stimulation with isoprenaline and FK-506.

DETAILED DESCRIPTION

Ryanodine Receptors: Excitation-contraction coupling (ECC) process

The sarcoplasmic reticulum (SR) is a structure in cells that functions, among other things, as a specialized intracellular calcium (Ca ²⁺ ) store. Ryanodine receptors (RyRs) are channels in the SR, which open and close to regulate the release of Ca ²⁺ from the SR into the intracellular cytoplasm of the cell. Release of Ca ²⁺ into the cytoplasm from the SR increases cytoplasmic Ca ²⁺ concentration. Open probability of RyRs refers to the likelihood that a RyR is open at any given moment, and therefore capable of releasing Ca ²⁺ into the cytoplasm from the SR. The RyR is the major Ca ²⁺ release channel on the SR responsible for excitation-contraction coupling (ECC) in striated muscle. Among the three known RyR isoforms (RyR1, RyR2 and RyR3),RyR1 is widely expressed and is the predominant isoform expressed in mammalian skeletal muscle. RyR2 is also widely expressed and is the predominant form found in cardiac muscle. RyR3 expression is low in adult skeletal muscle. RyR subtypes exhibit a high degree of structural and functional homology . The subtypes form a large sarcoplasmic membrane complex, consisting of four monomers that constitute a Ca ²⁺ release channel associated with proteins, such as kinases, phosphatases, phosphodiesterases, and other regulatory subunits.

Ca ²⁺ release from the SR is modulated by several RyR binding proteins. Calmodulin, a key mediator of Ca ²⁺ signaling, exerts both positive and negative effects on RyR open probability. Calstabinl (FKBP12) and calstabin2 (FKBP12.6) stabilize the closed state of RyR1 and RyR2, respectively. Calstabinl associates predominantly with skeletal muscle RyR1, while cardiac muscle RyR2 has the highest affinity for Calstabin2.

Mutations in RYR1 or RYR2 are characterized by inappropriate channel opening not related to contraction signals. This channel opening is further exacerbated by post-translational modifications such as PKA-phosphorylation, oxidation, or nitrosylation of the RyR channel. Leaky RyR is also implicated in disorders with wild-type RyR through post-translational modifications. This results in leaky channels, which exhibit a pathologic increase in the open probability under resting conditions. The SR Ca ²⁺ leak leads to a reduction in SR Ca ²⁺ content, with less Ca ²⁺ available for release and consequently weaker muscle contractions.

Mutations in RYR1 or RYR2 can also cause decreased binding of Calstabinl and Calstabin2, respectively. Stress-induced post-translational modifications of RyRs including PKA phosphorylation, oxidation, and nitrosylation also can cause decreased binding of Calstabins to RyR channels. Genetic mutations and/or stress-induced posttranslational modifications of the channel can result in dissociation of Calstabin from RyRs and cause the channels to become leaky channels. The dissociation of Calstabin can lead to leaky channels, which exhibit a pathologic increase in the open probability under resting conditions. The SR Ca ²⁺ leak leads to a reduction in SR Ca ²⁺ content, with less Ca ²⁺ available for release and consequently weaker muscle contractions. The intracellular calcium leak has distinct pathological consequences depending on which tissue is involved.

Ryanodine Receptor 2 and Cardiac Diseases The RyR2 channel plays a major role in intracellular calcium handling by regulating the release of Ca ²⁺ from the sarcoplasmic reticulum (SR) in cardiac myocytes required for ECC in cardiac muscle. The RyR2 channel is a macromolecular complex, which includes four identical RyR2 subunits, each of which binds one Calstabin2 (FKBP12.6), and other interacting proteins such as phosphatases and kinases. Binding of Calstabin2 stabilizes the channel in the closed state during the resting phase of the heart (diastole), thereby preventing diastolic calcium leak from the SR, and functionally couples groups of RyR2 channels to allow synchronous opening during excitationcontraction coupling.

Phosphorylation of RyR2 by protein kinase A (PKA) is an important part of the fight-or- flight response. Phosphorylation increases cardiac EC coupling gain by augmenting the amount of Ca ²⁺ released for a given trigger. The process strengthens muscle contraction and improves exercise capacity. This signaling pathway provides a mechanism by which activation of the sympathetic nervous system (SNS), in response to stress, results in increased cardiac output. Phosphorylation of RyR2 by PKA increases the sensitivity of the channel to calcium-dependent activation. The increased sensitivity leads to increased open probability and increased calcium release from the SR into the intracellular cytoplasm.

Heart failure (HF) is characterized by a sustained hyperadrenergic state in which serum catecholamine levels are chronically elevated. One consequence of this chronic hyperadrenergic state is persistent PKA hyperphosphorylation of RyR2, such that 3-4 out of the four Ser2808 in each homotetrameric RyR2 channel are chronically phosphorylated. Chronic PKA hyperphosphorylation of RyR2 is associated with depletion of the channel-stabilization subunit Calstabin2 from the RyR2 channel macromolecular complex. Depletion of Calstabin2 results in a diastolic SR Ca ²⁺ leak from the RyR complex and contributes to impaired contractility. Due to the activation of inward depolarizing currents, this diastolic SR Ca ²⁺ leak also is associated with fatal cardiac arrhythmias.

Mice engineered with RyR2 lacking the PKA phosphorylation site (RyR-S2808A) are protected from HF progression after myocardial infarction (MI). In addition, chronic PKA hyperphosphorylation of RyR2 in HF is associated with remodeling of the RyR2 macromolecular complex. The remodeling includes depletion of phosphatases PP1 and PP2a (impairing dephosphorylation of Ser2808) and the cAMP-specific type 4 phosphodiesterase (PDE4D3) from the RyR2 complex. Depletion of PDE4D3 from the RyR2 complex causes sustained elevation of local cAMP levels. Thus, diastolic SR Ca ²⁺ leak contributes to HF progression and arrhythmias. Additional post- translational modifications of the RyR channel (oxidation and nitrosylation) further drive the leak. Single-channel tracings of heart failure cardiomyocytes show a dramatic increase in open probability in RyR2 as compared with normal cardiomyocytes, indicating leaky channels. The large luminal SR Ca ²⁺ stores available in the normal state of the RyR channel are dramatically depleted in heart failure due to diastolic SR Ca ²⁺ leak via phosphorylated/oxidized RyR2. Ryanodine receptor channel modulators can stabilize ejection fraction by repairing calcium leak and thereby improve cardiac function in a mouse or rat heart failure model, e.g., acute heart failure or chronic heart failure.

In some embodiments, the heart failure is congestive heart failure. In some embodiments, the heart failure is chronic heart failure. In some embodiments, the heart failure is systolic heart failure. In some embodiments, the heart failure is diastolic heart failure. In some embodiments, the heart failure is acute decompensated heart failure. In some embodiments, the heart failure is heart failure with reduced ejection fraction (HFrEF). In some embodiments, the heart failure is heart failure with preserved ejection fraction. In some embodiments, the heart failure is acute heart failure, for example, for preservation of cardiac function post myocardial infarction or cardiomyopathy.

Premature Ventricular Contractions (PVCs) and Cardiomyopathy

Abnormal rhythms such as tachycardia, atrial fibrillation and those containing premature ventricular contractions (PVCs) are present in heart failure (HF) patients and can cause reversible dilated cardiomyopathy (CM). PVC-CM is defined as the development of left ventricular (LV) dysfunction caused primarily by frequent PVCs. Moreover, superimposed PVC-CM can be defined as worsening of left ventricular ejection fraction (LVEF) by at least 10% due to frequent PVCs in a previously known CM. PVC burden can be a predictor of PVC-CM. Two main studies have shown that PVC burden >16% and 24% best identifies patients with a diagnosis of PVC-CM (sensitivity and specificity of 79% to 100% and 78% to 87%, respectively). Although these and other studies suggest that a PVC burden of at least 10% is required to induce PVC-CM, other studies question this minimal PVC threshold, because they have shown improvement in LV function with PVC burden as low as 6% to 8%. PVC suppression is considered successful if burden is decreased by >80% of baseline PVCs, as it likely represents a true effect of treatment rather than spontaneous PVC variability. As demonstrated herein, a high proportion of PVCs (e.g., more than about 5% of all heartbeats in a time period, e.g., 24 hours) is associated with poor outcomes in heart failure. Inefficient contraction of the beat preceding the PVC is thought to help trigger the PVC. This preceding beat is also an inefficient (e.g., incomplete) contraction. Taken together, the number of inefficient (e.g., incomplete) contractions is actually two for each PVC, which then can lead to reduced cardiac output.

For example, if a subject has more than 5% PVCs of all heart beats in a time period, then the subject has more than about 10% of inefficient (i.e., incomplete) heart beats. As demonstrated herein, this can be associated with poor outcomes in heart failure.

Thus, in some embodiments, a high proportion of total inefficient (i.e., incomplete) heartbeats are associated with poor outcomes in heart failure. In some embodiments, poor outcomes in heart failure patient include, but are not limited to, increase in one or more cardiac events (e.g., ventricular arrhythmia), or death.

Reduction of PVCs by ablation of large scars has increased ejection fraction in patients with heart failure. However, most heart failure patients have diffuse, multi-focal scarring with associated high levels of PVCs, therefore not amenable to ablation. In some embodiments, these heart failure patients respond to therapy with calcium channel modulators (e.g., a compound of formulae (I), (II), (III), (IV), (1), or any other compound encompassed by such formulae, or otherwise described herein), leading to an increase efficiency of contraction and increased cardiac output.

In heart failure, Ca ²⁺ concentration in the sarcoplasmic reticulum (SR) can be abnormally regulated. Diastolic leak of Ca ²⁺ from the SR through modified leaky RyR2 Ca ²⁺ release channels can result in delayed after depolarizations (DADs). When the amplitude of a DAD is above a certain threshold (a suprathreshold DAD), it can trigger an action potential (AP) called triggered activity (TA), which can lead to a PVC. Ryanodine receptor channel modulators (e.g., a compound of formulae (I), (II), (III), (IV), (1), or any other compound encompassed by such formulae, or otherwise described herein) can preferentially bind to leaky RyR2 channels and induce a conformation change that can shift the open probability of the RyR2 channel towards a closed (resting) state, repairing the channel leak, thereby restoring normal RyR2 function. Therefore, Ryanodine receptor channel modulators can be effective at treating heart failure that is characterized by high burden of PVCs (e.g., more than about 5% of all heartbeats in a time period are PVCs; e.g., more than 10% of all heartbeats are incomplete heart beats). In some embodiments, repairing the channel leak results in a reduction in calcium flow (e.g., calcium sparks).

As used herein, the term “PVC burden” (the terms “burden of PVCs” and “PVC burden” are used interchangeably herein) is determined by monitoring the subject (e.g., a heart failure patient) during a defined time period, using electrocardiographic monitoring or any other system that detects and stores the measured electrical activity of the heart (e.g., a continuous cardiac monitoring system). In some embodiments, the PVC burden is calculated as the percentage of total PVCs in a given time period divided by the total number of beats during that same time period.

In some embodiments, the time period is from about 1 minute (60 seconds) to about 1 year. In some embodiments, the time period is from about 1 minute to about 6 months. In some embodiments, the time period is from about 1 minute to about 1 month. In some embodiments, the time period is from about 1 minute to about 2 weeks. In some embodiments, the time period is from about 1 minute to about 1 week. In some embodiments, the time period is from about 1 minute to about 24 hours. In some embodiments, the time period is from about 1 minute to about 12 hours. In some embodiments, the time period is from about 1 minute to about 10 hours. In some embodiments, the time period is from about 1 minute to about 5 hours. In some embodiments, the time period is from about 1 minute to about 1 hour. In some embodiments, the time period is from about 1 minute to about 30 minutes. In some embodiments, the time period is from about 5 minutes to about 30 minutes. In some embodiments, the time period is from about 5 minutes to about 10 minutes. In some embodiments, the time period is from about 10 minutes to about 15 minutes. =In some embodiments, the time period is from about 15 minutes to about 20 minutes. In some embodiments, the time period is from about 20 minutes to about 25 minutes. In some embodiments, the time period is from about 25 minutes to about 30 minutes. In some embodiments, the time period is from about 30 minutes to about 40 minutes. In some embodiments, the time period is from about 40 minutes to about 50 minutes. In some embodiments, the time period is from about 50 minutes to about 60 minutes. In some embodiments, the time period is from about 1 hour to about 5 hours. In some embodiments, the time period is from about 5 hours to about 10 hours. In some embodiments, the time period is from about 6 hours to about 12 hours. In some embodiments, the time period is from about 12 hours to about 18 hours. In some embodiments, the time period is from about 6 hours to about 12 hours. In some embodiments, the time period is from about 12 hours to about 18 hours. In some embodiments, the time period is from about 18 hours to about 24 hours. In some embodiments, the time period is 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 24, 48, 72 or 168 hours or any range encompassed within 1-168 hours. In some embodiments, the time period can extend beyond 168 hours. In some embodiments, the time period is 60 seconds (1 minute). In some embodiments, the time period is 24 hours (1 day). In some embodiments, the time period is 12 months (1 year).

DAD-triggered PVCs are distinguished mechanistically from early after depolarizations (EADs), which often occur during bradycardia episodes. In some embodiments, the present disclosure relates to methods of treating a subject having heart failure that is characterized by a premature ventricular contraction (PVC) burden of at least about 5% of all heartbeats in a time period; in this scenario the, PVC can be triggered by a DAD that results from a diastolic leak of Ca ²⁺ from the SR through modified leaky RyR2 Ca ²⁺ release channels.

In some embodiments, a method of treating a subject with a Ryanodine Receptor calcium channel modulator is disclosed. The method comprises determining if the subject has heart failure characterized by (a) a premature ventricular contraction (PVC) burden of at least about 5% of all heartbeats in a time period, wherein the PVC initiates after end of a T-wave of a preceding heartbeat; and (b) a heart rate preceding the PVC of at least about 60 beats per minute. The method comprises administering a therapeutically effective amount of the Ryanodine Receptor calcium channel modulator to the subject.

PVCs can originate from multiple or single foci (locations), and the resultant PVCs can be expressed by uniform or multiform appearance on the resultant ECG. In some embodiments, the PVCs are unifocal (i.e., they have a single uniform morphology of the ectopic beats on a surface ECG). In some embodiments, the PVCs are multi-focal (i.e., they originate from two or more foci, resulting in at least two distinct morphologies on surface ECG). In some embodiments, the PVCs are not unifocal, i.e., they have at least two distinct morphologies, irrespective of the origin. For example, the PVCs can (i) arise from the same foci but have different morphologies; or (ii) arise from different foci and have different morphologies. In some embodiments, the PVCs can arise from the left ventricle (e.g., left bundle branch block morphology with dominant S wave in V1). In some embodiments, the PVCs can arise from the right ventricle (e.g., right bundle branch block morphology with dominant R wave in V1).

In some embodiments, the subject has PVCs with at least two morphologies. In some embodiments, the morphologies are different from each other. In some embodiments, the PVCs are not unifocal. In some embodiments, the PVCs are multi-focal. In some embodiments, the PVCs originate from the same foci. In other embodiments, the PVCs originate from different foci. In some embodiments, the treatment of the subject decreases the number of PVCs. In some embodiments, the treatment of the subject improves left ventricular function hemodynamics. In some embodiments, the treatment of the subject improves ejection fraction. In some embodiments, the treatment of the subject decreases the level of N-terminal pro-b-type natriuretic peptide (NT- proBNP). In some embodiments, the treatment of the subject decreases PVCs by greater than about fifty percent (50%). In some embodiments, the treatment of the subject decreases PVCs by greater than about 60%, 65%, 70%, 75%, 85%, 90%, 95%, 100%, or any number in between. In some embodiments, the treatment of the subject decreases PVCs by greater than about eighty percent (80%). In some embodiments, the compound is administered as monotherapy. In some embodiments, the compound is administered in combination therapy.

In some embodiments, the PVC initiates at least about 100 msec after end of a T-wave of a preceding heartbeat. In some embodiments, a method of identifying a subject for treatment with a Ryanodine Receptor calcium channel modulator is disclosed. The method comprises determining if the subject has heart failure, wherein the heart failure is characterized by (a) a premature ventricular contraction (PVC) burden of at least about 5% of all heartbeats in a time period, wherein the PVC initiates at least about 100 msec after end of a T-wave of a preceding heartbeat; and (b) a heart rate preceding the PVC of at least about 60 beats per minute.

In some embodiments, the PVC burden ranges from about 5% of all heartbeats to about 20% of all heartbeats. In some embodiments, the PVC burden ranges from about 5% of all heartbeats to about 15 % of all heartbeats within a time period. In some embodiments, the PVC burden ranges from about 5% of all heartbeats to about 10 % of all heartbeats within a time period. In some embodiments, the PVC burden is at least about 6% of all heartbeats within a time period. In some embodiments, the PVC burden is at least about 7% of all heartbeat within a time period s. In some embodiments, the PVC burden is at least about 8% of all heartbeats within a time period. In some embodiments, the PVC burden is at least about 9% of all heartbeats within a time period. In some embodiments, the PVC burden is at least about 10% of all heartbeats within a time period. In some embodiments, the PVC burden is at least about 11% of all heartbeats within a time period. In some embodiments, the PVC burden is at least about 12% of all heartbeats within a time period. In some embodiments, the PVC burden is at least about 13% of all heartbeats within a time period. In some embodiments, the PVC burden is at least about 14% of all heartbeats within a time period. In some embodiments, the PVC burden is at least about 15% of all heartbeats within a time period. In some embodiments, the PVC burden is at least about 16% of all heartbeats within a time period. In some embodiments, the PVC burden is at least about 17% of all heartbeats within a time period. In some embodiments, the PVC burden is at least about 18% of all heartbeats within a time period. In some embodiments, the PVC burden is at least about 19% of all heartbeats within a time period. In some embodiments, the PVC burden is at least about 20% of all heartbeats within a time period. In some embodiments, the time period is 1 minute (60 seconds). In some embodiments, the time period is 24 hours. In some embodiments, the time period is one year. As contemplated herein, because the beat preceding the PVC is an inefficient (e.g., incomplete) contraction, the number of inefficient (e.g., incomplete) contractions is actually two for each PVC.

In some embodiments, the heart rate preceding the PVC is at least about 60 beats per minute. In some embodiments, the heart rate preceding the PVC is at least about 70 beats per minute. In some embodiments, the heart rate preceding the PVC is at least about 80 beats per minute. In some embodiments, the heart rate preceding the PVC is at least about 90 beats per minute. In some embodiments, the heart rate preceding the PVC is at least about 100 beats per minute. In some embodiments, the heart rate preceding the PVC is at from about 60 beats per minute to about 100 beats per minute, from about 60 beats per minute to about 90 beats per minute, from about 60 beats per minute to about 70 beats per minute, from about 60 beats per minute to about 65 beats per minute, from about 65 beats per minute to about 70 beats per minute, from about 75 beats per minute to about 80 beats per minute, from about 80 beats per minute to about 85 beats per minute, from about 85 beats per minute to about 90 beats per minute, from about 90 beats per minute to about 95 beats per minute, or from about 95 beats per minute to about 100 beats per minute.

In some embodiments, the subject has heart failure with reduced ejection fraction (HFrEF). In some embodiments, the subject has an ejection fraction less than about 40%. In some embodiments, the subject has an ejection fraction less than about 39%, 38%, 37%, 36%, 35%, 34%, 33%, 32%, 31%, 30%, 29%, 28%, 27%, 26%, 25%, 24%, 23%, 22%, 21%, 20%, or even lower.

In some embodiments, the heart failure is further characterized by an N-terminal pro-b-type natriuretic peptide test greater than about 1,000 pg/mL. In some embodiments, the heart failure is further characterized by an N-terminal pro-b-type natriuretic peptide test greater than about 1500 pg/mL. In some embodiments, the heart failure is further characterized by an N-terminal pro-b-type natriuretic peptide test greater than about 600 pg/mL. In some embodiments, the heart failure is further characterized by an N-terminal pro-b-type natriuretic peptide test greater than about 650 pg/mL. In some embodiments, the heart failure is further characterized by an N-terminal pro-b-type natriuretic peptide test greater than about 700 pg/mL. In some embodiments, the heart failure is further characterized by an N-terminal pro-b-type natriuretic peptide test greater than about 750 pg/mL. In some embodiments, the heart failure is further characterized by an N-terminal pro-b-type natriuretic peptide test greater than about 800 pg/mL. In some embodiments, the heart failure is further characterized by an N-terminal pro-b-type natriuretic peptide test greater than about 850 pg/mL. In some embodiments, the heart failure is further characterized by an N-terminal pro-b-type natriuretic peptide test greater than about 900 pg/mL. In some embodiments, the heart failure is further characterized by an N-terminal pro-b-type natriuretic peptide test greater than about 950 pg/mL.

Combination Therapy

In some embodiments, a compound of the disclosure (e.g., a compound of formulae (I), (II), (III), (IV), (1), or any other compound encompassed by such formulae, or otherwise described herein) is administered in combination with one or more additional therapies. In some embodiments, the compound is administered in combination with another drug used to treat heart failure. Examples of drugs used to treat heart failure include, but are not limited to, a beta-blocker, an angiotensin-converting enzyme (ACE) inhibitor or an angiotensin receptor blocker (ARB).

In some embodiments, the beta-blocker (or other heart failure drug) is administered in a reduced amount, wherein the reduced amount is about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, or about 95% of the amount used to treat heart failure in the subject in absence of the compound of the disclosure.

An amount of beta-blocker or other heart failure drug that is less than an amount that is used to treat heart failure in absence of the compound of the disclosure can be less than a maximum tolerated dose of the beta blocker or other heart failure drug, which can be, for example, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%. about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, or about 95% less than a maximum tolerated dose of the beta blocker. An amount of beta-blocker or other heart failure drug that is less than an amount that is used to treat heart failure in absence of the compound of the disclosure can be an amount that is less than a dose of the beta blocker that is therapeutically effective for heart failure in absence of the compound or pharmaceutically- acceptable salt thereof, which can be, for example, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, or about 95% less than a dose of the beta blocker that is therapeutically effective for heart failure in absence of the compound of the disclosure.

Non-limiting examples of beta-blockers include acebutolol, atenolol, betaxolol, bisoprolol, bucindolol, butaxamine, carteolol, carvedilol, celiprolol, esmolol, labetalol, metoprolol, nadolol, nebivolol, oxprenolol, penbutolol, pindolol, propranolol, sotalol, timolol, and pharmaceutically- acceptable salt. In some embodiments the beta-blocker is a non-selective beta-blocker. A non- selective beta-blocker inhibits both beta-1 receptors located primarily in cardiac muscle, and beta-2 receptors located primarily in the bronchial and vascular musculature. In some embodiments, a non- selective beta-blocker is nadolol, penbutolol, pindolol, propranolol, sotalol, or timolol, or pharmaceutically acceptable-salts thereof.

In an embodiment, a non-selective beta-blocker is nadolol or a pharmaceutically-acceptable salt thereof. In some embodiments, the beta-blocker is a selective beta-blocker. Selective beta blockers (such as metoprolol) can preferentially inhibit beta 1 receptors (cardio- selective). At very high concentrations, this selectivity can be reduced and some beta 2 inhibition can occur. Selectivity is confirmed by the inability to reverse the beta 2-mediated vasodilating effects of epinephrine. This contrasts with the effect of nonselective beta-blockers, which can be capable of reversing the vasodilating effects of epinephrine. In some embodiments, a selective beta-blocker is metoprolol or a pharmaceutically-acceptable salt thereof.

Non-limiting examples of ACE inhibitors include benazepril, captopril, enalapril, fosiopril, lisinopril, moexipril, perindopril, quinapril, ramipril, trandolapril, and pharmaceutically-acceptable salts thereof.

Non-limiting examples of ARBs include azilsartan, candesartan, eprosartan, irbesartan, Losartan, Olmesartan, Telmisartan, Valsartan, and pharmaceutically-acceptable salts thereof.

Compounds

In some embodiments, the calcium channel modulator is represented by the following structure: wherein R is COOH, or a pharmaceutically-acceptable salt thereof. In some embodiments, the calcium channel modulator is in the form of a salt with a pharmaceutically-acceptable acid or base. In some embodiments, the salt is selected from the group consisting of hemifumarate, sodium, potassium, magnesium, hydrochloride and hydrobromide, preferably wherein the salt is the sodium or the hemifumarate salt.

In some embodiments, the calcium channel modulator is represented by the following structure: or a pharmaceutically-acceptable salt thereof. In some embodiments, the pharmaceutically- acceptable salt is a hemi-fumarate salt.

In some embodiments, the compound is selected from:

or pharmaceutically-acceptable salts thereof.

In some embodiments, the calcium channel modulator is represented by the following structure: wherein, n is 0, 1, or 2; q is 0, 1, 2, 3, or 4; each R is independently acyl, -O-acyl, alkyl, alkoxyl, alkylamino, alkylarylamino, alkylthio, cycloalkyl, alkylaryl, aryl, heteroaryl, heterocyclyl, heterocyclylalkyl, alkenyl, alkynyl, arylthio, arylamino, heteroarylthio, or heteroarylamino, each of which is independently substituted or unsubstituted; or halogen, -OH, -NH ₂ , -NO ₂ , -CN, -CF ₃ , -OCF ₃ , -N ₃ , -SO ₃ H, - S(=O) ₂ alkyl, -S(=O)alkyl. or -OS(=O) ₂ CF ₃ ;

R ¹ is alkyl, alkenyl, aryl, alkylaryl, cycloalkyl, heteroaryl, or heterocyclyl, each of which is independently substituted or unsubstituted; or H;

R ² is alkyl, aryl, alkylaryl, heteroaryl, cycloalkyl, cycloalkylalkyl, or heterocyclyl, each of which is independently substituted or unsubstituted; or H, -C(=O)R ⁵ , -C(=S)R ⁶ , -SO ₂ R ⁷ , - P(=O)R ⁸ R ⁹ , or -(CH ₂ ) _m -R ¹⁰ ;

R ³ is acyl, -O-acyl, alkyl, alkenyl, aryl, alkylaryl, cycloalkyl, heteroaryl, or heterocyclyl, each of which is independently substituted or substituted; or H, -CO ₂ Y, or -C(=O)NHY ; Y is alkyl, aryl, alkylaryl, cycloalkyl, heteroaryl, or heterocyclyl, each of which is independently substituted or unsubstituted; or H;

R ⁴ is alkyl, alkenyl, aryl, alkylaryl, cycloalkyl, heteroaryl, or heterocyclyl, each of which is independently substituted or unsubstituted; or H; each R ⁵ is acyl, alkyl, alkenyl, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or -NR ¹⁵ R ¹⁶ , -(CH ₂ ) _t NR ¹⁵ R ¹⁶ , -NHNR ¹⁵ R ¹⁶ , -NHOH, -OR ¹⁵ , - C(=O)NHNR ¹⁵ R ¹⁶ . -CO ₂ R ¹⁵ , -C(=O)NR ¹⁵ R ¹⁶ . or -CH ₂ X; each R ⁶ is acyl, alkenyl, alkyl, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or -OR ¹⁵ , -NHNR ¹⁵ R ¹⁶ , -NHOH, -NR ¹⁵ R ¹⁶ , or -CH ₂ X; each R ⁷ is alkyl, alkenyl, alkynyl, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or -OR ¹⁵ , -NR ¹⁵ R ¹⁶ , -NHNR ¹⁵ R ¹⁶ , -NHOH, or -CH ₂ X; each R ⁸ and R ⁹ arc each independently acyl, alkenyl, alkoxyl, alkyl, alkylamino, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or OH; each R ¹⁰ is -NR ¹⁵ R ¹⁶ , OH, -SO ₂ R ⁿ , -NHSO ₂ R ⁿ , -C(=O)(R ¹² ), -NHC=O(R ¹² ), -OC=O(R ¹² ), or -P(=O)R ¹³ R ¹⁴ ; each R ¹¹ , R ¹² , R ¹³ , and R ¹⁴ is independently acyl, alkenyl, alkoxyl, alkyl, alkylamino, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or H, OH, NH ₂ , -NHNH ₂ , or -NHOH; each X is independently halogen, -CN, -CO ₂ R ¹⁵ , -C(=O)NR ¹⁵ R ¹⁶ , -NR ¹⁵ R ¹⁶ , -OR ¹⁵ , -SO ₂ R ⁷ , or -P(=O)R ⁸ R ⁹ ; and each R ¹⁵ and R ¹⁶ is independently acyl, alkenyl, alkoxyl, OH, NH ₂ , alkyl, alkylamino, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted, or H; or R ¹⁵ and R ¹⁶ together with the N to which R ¹⁵ and R ¹⁶ are bonded form a heterocycle that is substituted or unsubstituted; t is 1, 2, 3, 4, 5, or 6; m is 1, 2, 3, or 4; or a pharmaceutically-acceptable salt thereof. In some embodiments, the calcium channel modulator is represented by the following structure: wherein: n is 0, 1, or 2; q is 0, 1, 2, 3, or 4; each R is independently acyl, -O-acyl, alkyl, alkoxyl, alkylamino, alkylarylamino, alkylthio, cycloalkyl, alkylaryl, aryl, heteroaryl, heterocyclyl, heterocyclylalkyl, alkenyl, alkynyl, arylthio, arylamino, heteroarylthio, or heteroarylamino, each of which is independently substituted or unsubstituted; or halogen, -OH, -NH ₂ , -NO ₂ . -CN, -CF ₃ , -OCF ₃ , -N ₃ , -SO ₃ H, - S(=O) ₂ alkyl, -S(=O)alkyl, or -OS(=O) ₂ CF ₃ ;

R ² is alkyl, aryl, alkylaryl, heteroaryl, cycloalkyl, cycloalkylalkyl, or heterocyclyl, each of which is independently substituted or unsubstituted; or H, -C(=O)R ⁵ , -C(=S)R ⁶ , -SO ₂ R ⁷ , - P(=O)R ⁸ R ⁹ , or -(CH ₂ ) _m -R ¹⁰ ; each R ⁵ is acyl, alkyl, alkenyl, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or -NR ¹⁵ R ¹⁶ , -NHNR ¹⁵ R ¹⁶ , -NHOH, -OR ¹⁵ , -C(=O)NHNR ¹⁵ R ¹⁶ , -CO ₂ R ¹⁵ , - C(=O)NR ¹⁵ R ¹⁶ , -CH ₂ X, or alkyl substituted by at least one labeling group, selected from a fluorescent group, a bioluminescent group, a chemiluminescent group, a colorimetric group, and a radioactive labeling group; each R ⁶ is acyl, alkenyl, alkyl, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or -OR ¹⁵ , -NHNR ¹⁵ R ¹⁶ , -NHOH, -NR ¹⁵ R ¹⁶ , or -CH ₂ X; each R ⁷ is alkyl, alkenyl, alkynyl, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or -OR ¹⁵ , -NR ¹⁵ R ¹⁶ , -NHNR ¹⁵ R ¹⁶ , -NHOH, or -CH ₂ X; each R ⁸ and R ⁹ are each independently acyl, alkenyl, alkoxyl, alkyl, alkylamino, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or OH; each R ¹⁰ is -NR ¹⁵ R ¹⁶ , OH, -SO ₂ R ¹¹ , -NHSO ₂ R ¹¹ , -C(=O)R ¹² , -NH(C=O)R ¹² , -O(C=O)R ¹² , or -P(=O)R ¹³ R ¹⁴ ; m is 0, 1, 2, 3, or 4; each R ¹¹ , R ¹² , R ¹³ , and R ¹⁴ is independently acyl, alkenyl, alkoxyl, alkyl, alkylamino, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or H, OH, NH ₂ , -NHNH ₂ , or -NHOH; each X is halogen, -CN, -CO ₂ R ¹⁵ , -C(=O)NR ¹⁵ R ¹⁶ , -NR ¹⁵ R ¹⁶ , -OR ¹⁵ , -SO ₂ R ⁷ , or - P(=O)R ⁸ R ⁹ ; and each R ¹⁵ and R ¹⁶ is independently acyl, alkenyl, alkoxyl, OH, NH ₂ , alkyl, alkylamino, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted, or H; or R ¹⁵ and R ¹⁶ together with the N to which R ¹⁵ and R ¹⁶ are bonded form a heterocycle that is substituted or unsubstituted; or a pharmaceutically-acceptable salt thereof.

In some embodiments, calcium channel modulator comprises the following structure: wherein

R' and R" are each independently acyl, alkyl, alkoxyl, alkylamino, alkylthio, cycloalkyl, aryl, heterocyclyl, heterocyclylalkyl, alkenyl, alkynyl, aryl, heteroaryl, arylthiol, heteroarylthio, arylamino, or heteroarylamino, each of which is independently substituted or substituted; or halogen, H. -OH, -NH ₂ , -NO ₂ , -CN, -CF ₃ , -OCF ₃ . -N ₃ , -SO ₃ H. -S(=O) ₂ alkyl. -S(=O)alkyl, or -OS(=O) ₂ CF ₃ ;

R ² is alkyl, aryl, alkylaryl, heteroaryl, cycloalkyl, cycloalkylalkyl, or heterocyclyl, each of which is independently substituted or unsubstituted; or H, -C(=O)R ⁵ , -C(=S)R ⁶ , -SO ₂ R ⁷ , - P(=O)R ⁸ R ⁹ , or -(CH ₂ ) _m -R ¹⁰ ; and n is 0, 1, or 2; or a pharmaceutically-acceptable salt thereof. In some embodiments, the calcium channel modulator is represented by the following structure: wherein n is 0, 1, or 2; q is 0, 1, 2, 3, or 4; each R is independently acyl, -O-acyl, alkyl, alkoxyl, alkylamino, alkylarylamino, alkylthio, cycloalkyl, alkylaryl, aryl, heteroaryl, heterocyclyl, heterocyclylalkyl, alkenyl, alkynyl, arylthio, arylamino, heteroarylthio, or heteroarylamino, each of which is independently substituted or unsubstituted; or halogen, -OH, -NH ₂ , -NO ₂ . -CN, -CF ₃ , -OCF ₃ , -N ₃ , -SO ₃ H, - S(=O) ₂ alkyl, -S(=O)alkyl, or -OS(=O) ₂ CF ₃ ; each R ⁷ is alkyl, alkenyl, alkynyl, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or -OR ¹⁵ , -NR ¹⁵ R ¹⁶ , -NHNR ¹⁵ R ¹⁶ , -NHOH, or -CH ₂ X; or a pharmaceutically-acceptable salt thereof.

In some embodiments, the calcium channel modulator is represented by the following structure: wherein n is 0, 1, or 2;

R' and R" are each independently acyl, alkyl, alkoxyl, alkylamino, alkylthio, cycloalkyl, aryl, heterocyclyl, heterocyclylalkyl, alkenyl, alkynyl, aryl, heteroaryl, arylthiol, heteroarylthio, arylamino, or heteroarylamino, each of which is independently substituted or substituted; or halogen, H, -OH, -NH ₂ , -NO ₂ , -CN, -CF ₃ , -OCF ₃ , -N ₃ , -SO ₃ H, -S(=O) ₂ alkyl, -S(=O)alkyl, or -OS(=O) ₂ CF ₃ ; each R ⁷ is alkyl, alkenyl, alkynyl, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or -OR ¹⁵ , -NR ¹⁵ R ¹⁶ , -NHNR ¹⁵ R ¹⁶ , -NHOH, or -CH ₂ X, or a pharmaceutically-acceptable salt thereof.

In some embodiments, the calcium channel stabilizer comprises the following structure: wherein n is 0, 1, or 2; q is 0, 1, 2, 3, or 4; each R is independently acyl, -O-acyl, alkyl, alkoxyl, alkylamino, alkylarylamino, alkylthio, cycloalkyl, alkylaryl, aryl, heteroaryl, heterocyclyl, heterocyclylalkyl, alkenyl, alkynyl, arylthio, arylamino, heteroarylthio, or heteroarylamino, each of which is independently substituted or unsubstituted; or halogen, -OH, -NH ₂ , -NO ₂ . -CN, -CF ₃ , -OCF ₃ , -N ₃ , -SO ₃ H, - S(=O) ₂ alkyl, -S(=O)alkyl, or -OS(=O) ₂ CF ₃ ; and each R ⁵ is acyl, alkyl, alkenyl, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or-NR ¹⁵ R ¹⁶ , -NHNR ¹⁵ R ¹⁶ , -NHOH, -OR ¹⁵ , -C(=O)NHNR ¹⁵ R ¹⁶ , -CO ₂ R ¹⁵ , - C(=O)NR ¹⁵ R ¹⁶ , -CH ₂ X, or alkyl substituted by at least one labeling group, selected from a fluorescent group, a bioluminescent group, a chemiluminescent group, a colorimetric group, and a radioactive labeling group, or a pharmaceutically-acceptable salt thereof.

In some embodiments, the calcium channel modulator is represented by the following structure: wherein n is 0, 1, or 2;

R' and R" are each independently acyl, alkyl, alkoxyl, alkylamino, alkylthio, cycloalkyl, aryl, heterocyclyl, heterocyclylalkyl, alkenyl, alkynyl, aryl, heteroaryl, arylthiol, heteroarylthio, arylamino, or heteroarylamino, each of which is independently substituted or substituted; or halogen. H, -OH, -NH ₂ , -NO ₂ . -CN. -CF ₃ , -OCF ₃ , -N ₃ . -SO ₃ H, -S(=O) ₂ alkyl, -S(=O)alkyl. or -OS(=O) ₂ CF ₃ ; each R ⁵ is acyl, alkyl, alkenyl, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or- NR ¹⁵ R ¹⁶ , -NHNR ¹⁵ R ¹⁶ , -NHOH, -OR ¹⁵ , -C(=O)NHNR ¹⁵ R ¹⁶ , -CO ₂ R ¹⁵ , - C(=O)NR ¹⁵ R ¹⁶ , -CH ₂ X, or alkyl substituted by at least one labeling group, selected from a fluorescent group, a bioluminescent group, a chemiluminescent group, a colorimetric group, and a radioactive labeling group, or a pharmaceutically-acceptable salt thereof.

In some embodiments, the calcium channel stabilizer comprises the following structure: wherein n is 0, 1, or 2; q is 0, 1, 2, 3, or 4;

W is S or O; each R is independently acyl, -O-acyl, alkyl, alkoxyl, alkylamino, alkylarylamino, alkylthio, cycloalkyl, alkylaryl, aryl, heteroaryl, heterocyclyl, heterocyclylalkyl, alkenyl, alkynyl, arylthio, arylamino, heteroarylthio, or heteroarylamino, each of which is independently substituted or unsubstituted; or halogen, -OH, -NH ₂ , -NO ₂ . -CN, -CF ₃ , -OCF ₃ , -N ₃ , -SO ₃ H, - S(=O) ₂ alkyl, -S(=O)alkyl, or -OS(=O) ₂ CF ₃ ; each R ¹⁵ and R ¹⁶ is independently acyl, alkenyl, alkoxyl, OH, NH ₂ , alkyl, alkylamino, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted, or H; or R ¹⁵ and R ¹⁶ together with the N to which R ¹⁵ and R ¹⁶ are bonded may form a heterocycle that is substituted or unsubstituted, or a pharmaceutically-acceptable salt thereof.

In some embodiments, calcium channel stabilizer comprises the following structure: wherein n is 0, 1, or 2;

W is S or O;

R' and R" are each independently acyl, alkyl, alkoxyl, alkylamino, alkylthio, cycloalkyl, aryl, heterocyclyl, heterocyclylalkyl, alkenyl, alkynyl, aryl, heteroaryl, arylthiol, heteroarylthio, arylamino, or heteroarylamino, each of which is independently substituted or substituted; or halogen, H, -OH, -NH ₂ , -NO ₂ , -CN, -CF ₃ , -OCF ₃ . -N ₃ , -SO ₃ H. -S(=O) ₂ alkyl. -S(=O)alkyl, or -OS(=O) ₂ CF ₃ , or a pharmaceutically-acceptable salt thereof.

In some embodiments, the compound is of formula wherein R' and R" are each independently H, halogen, -OH, OMe, -NH ₂ , -NO ₂ , -CN, -CF ₃ , -OCF ₃ , -N ₃ , -S(=O) ₂ C ₁ -C ₄ alkyl, - S(=O)C ₁ -C ₄ alkyl, -S-C ₁ -C ₄ alkyl, -OS(=O) ₂ CF ₃ , Ph, -NHCH ₂ Ph, -C(=O)Me, -OC(=O)Me, morpholinyl, or propenyl; and n is 0, 1 or 2. In some embodiments, R' is H or OMe, and R" is H.

In some embodiments, the present disclosure provides a compound of formula of Il-i: wherein

R ¹⁷ is alkenyl, aryl, cycloalkyl, cycloalkylalkyl, heterocyclyl, and heterocyclylalkyl, each of which is independently substituted or unsubstituted; or -NR ¹⁵ R ¹⁶ , -NHNR ¹⁵ R ¹⁶ , -NHOH, - OR ¹⁵ , or -CH ₂ X; n is 0, 1, or 2; q is 0, 1, 2, 3, or 4; and each R is independently acyl, -O-acyl, alkyl, alkoxyl, alkylamino, alkylarylamino, alkylthio, cycloalkyl, alkylaryl, aryl, heteroaryl, heterocyclyl, heterocyclylalkyl, alkenyl, alkynyl, arylthio, arylamino, heteroarylthio, or hetero arylamino, each of which is independently substituted or unsubstituted; or halogen, -OH, -NH ₂ , -NO ₂ , -CN, -CF ₃ , -OCF ₃ , -N ₃ , -SO ₃ H, - S(=O) ₂ alkyl. -S(=O)alkyl, or -OS(=O) ₂ CF ₃ , or a pharmaceutically-acceptable salt thereof.

In some embodiments, the calcium channel modulator is represented by the following structure: wherein

R' and R" are each independently acyl, alkyl, alkoxyl, alkylamino, alkylthio, cycloalkyl, aryl, heterocyclyl, heterocyclylalkyl, alkenyl, alkynyl, aryl, heteroaryl, arylthiol, heteroarylthio, arylamino, or heteroarylamino, each of which is independently substituted or substituted; or halogen, H. -OH, -NH ₂ , -NO ₂ , -CN, -CF ₃ , -OCF ₃ . -N ₃ , -SO ₃ H, -S(=O) ₂ alkyl, -S(=O)alkyl, or -OS(=O) ₂ CF ₃ ;

R ¹⁷ is selected from the group consisting of -NR ₁₅ R ₁₆ , -NHOH, -OR ¹⁵ , -CH ₂ X, alkenyl, aryl, cycloalkyl, cycloalkylalkyl, heterocyclyl, and heterocyclylalkyl; wherein each alkenyl, aryl. cycloalkyl, cycloalkylalkyl, heterocyclyl, and heterocyclylalkyl may be substituted or unsubstituted; n is 0, 1, or 2, or a pharmaceutically-acceptable salt thereof.

In some embodiments, the calcium channel modulator is represented by formula Il-k or Il-k- wherein each R is independently acyl, -O-acyl, alkyl, alkoxyl, alkylamino, alkylarylamino, alkylthio, cycloalkyl, alkylaryl, aryl, heteroaryl, heterocyclyl, heterocyclylalkyl, alkenyl, alkynyl, arylthio, arylamino, heteroarylthio, or hetero arylamino, each of which is independently substituted or unsubstituted; or halogen, -OH, -NH ₂ , -NO ₂ , -CN. -CF ₃ , -OCF ₃ , -N ₃ , -SO ₃ H, - S(=O) ₂ alkyl, -S(=O)alkyl, or -OS(=O) ₂ CF ₃ ;

R' and R" are each independently acyl, alkyl, alkoxyl, alkylamino, alkylthio, cycloalkyl, aryl, heterocyclyl, heterocyclylalkyl, alkenyl, alkynyl, aryl, heteroaryl, arylthiol, heteroarylthio, arylamino, or heteroarylamino, each of which is independently substituted or substituted; or halogen, H, -OH, -NH ₂ , -NO ₂ , -CN, -CF ₃ , -OCF ₃ , -N ₃ , -SO ₃ H, -S(=O) ₂ alkyl, -S(=O)alkyl, or -OS(=O) ₂ CF ₃ ;

R ¹⁸ is alkyl, aryl, cycloalkyl, or heterocyclyl, each of which is independently substituted or unsubstituted; or -NR ¹⁵ R ¹⁶ , -C(=O)NR ¹⁵ R ¹⁶ , -(C=O)OR ¹⁵ , or -OR ¹⁵ ; q is 0, 1, 2, 3, or 4; p is 1, 2, 3, 4, 5, 6, 7, 8 9, or 10; and n is 0, 1, or 2, or a pharmaceutically-acceptable salt thereof.

In another embodiment, the calcium channel modulator is represented by the following structure: wherein

R' and R" are each independently acyl, alkyl, alkoxyl, alkylamino, alkylthio, cycloalkyl, aryl, heterocyclyl, heterocyclylalkyl, alkenyl, alkynyl, aryl, heteroaryl, arylthiol, heteroarylthio, arylamino, or heteroarylamino, each of which is independently substituted or substituted; or halogen, H, -OH, -NH ₂ , -NO ₂ , -CN, -CF ₃ , -OCF ₃ , -N ₃ , -SO ₃ H, -S(=O) ₂ alkyl, -S(=O)alkyl, or -OS(=O) ₂ CF ₃ ;

R ¹⁸ is alkyl, aryl, cycloalkyl, or heterocyclyl, each of which is independently substituted or unsubstituted; or -NR ¹⁵ R ¹⁶ , -C(=O)NR ¹⁵ R ¹⁶ , -(C=O)OR ¹⁵ , or -OR ¹⁵ ; p is 1, 2, 3, 4, 5, 6, 7, 8 9, or 10; and n is 0, 1, or 2, or a pharmaceutically-acceptable salt thereof.

In some embodiments of formula I-k-1 R’ and R” are independently selected from the group consisting of H, halogen, -OH, OMe. -NH ₂ , -NO ₂ , -CN, -CF ₃ , -OCF ₃ , -N ₃ , -S(=O) ₂ C ₁ -C ₄ alkyl, - S(=O)C ₁ -C ₄ alkyl, -S-C ₁ -C ₄ alkyl, -OS(=O) ₂ CF ₃ , Ph, -NHCH ₂ Ph, -C(=O)Me, -OC(=O)Me, morpholinyl and propenyl; and n is 0, 1 or 3. In some cases, R’ is H or OMe, and R” is H.

In other embodiments, R ¹⁸ is selected from the group consisting of — NR ¹⁵ R ¹⁶ , -(C=O)OR ¹⁵ , -OR ¹⁵ , alkyl that is substituted or unsubstituted, or aryl that is substituted or unsubstituted. In some embodiments, m is 1, and R ¹⁸ is Ph, -C(=O)OMe, -C(=O)OH, aminoalkyl, NH ₂ , NHOH, or NHCbz. In other embodiments, m is 0, and R ¹⁸ is C ₁ -C ₄ alkyl. In other embodiments, R ¹⁸ is Me, Et, propyl, and butyl. In some embodiments, m is 2, and R ¹⁸ is pyrrolidine, piperidine, piperazine, or morpholine. In some embodiments, m is 3, 4, 5, 5, 7, or 8, and R ¹⁸ is a fluorescent labeling group selected from bodipy, dansyl, fluorescein, rhodamine, Texas red, cyanine dyes, pyrene, coumarins, Cascade Blue™, Pacific Blue, Marina Blue, Oregon Green, 4',6-Diamidino-2-phenylindole (DAPI), indopyra dyes, lucifcr yellow, propidium iodide, porphyrins, arginine, and variants and derivatives thereof.

In some embodiments, the calcium channel modulator is represented by the following structure: wherein each R is independently acyl, -O-acyl, alkyl, alkoxyl, alkylamino, alkylarylamino, alkylthio, cycloalkyl, alkylaryl, aryl, heteroaryl, heterocyclyl, heterocyclylalkyl, alkenyl, alkynyl, arylthio, arylamino, heteroarylthio, or hetero arylamino, each of which is independently substituted or unsubstituted; or halogen, -OH, -NH ₂ , -NO ₂ , -CN, -CF ₃ , -OCF ₃ , -N ₃ , -SO ₃ H, - S(=O) ₂ alkyl, -S(=O)alkyl, or -OS(=O) ₂ CF ₃ ;

R' and R" are each independently acyl, alkyl, alkoxyl, alkylamino, alkylthio, cycloalkyl, aryl, heterocyclyl, heterocyclylalkyl, alkenyl, alkynyl, aryl, heteroaryl, arylthiol, heteroarylthio, arylamino, or heteroarylamino, each of which is independently substituted or substituted; or halogen, H, -OH, -NH ₂ , -NO ₂ , -CN, -CF ₃ , -OCF ₃ , -N ₃ , -SO ₃ H, -S(=O) ₂ alkyl, -S(=O)alkyl, or -OS(=O) ₂ CF ₃ ;

R ⁶ is acyl, alkenyl, alkyl, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or -OR ¹⁵ . -NHNR ¹⁵ R ¹⁶ , -NHOH, -NR ¹⁵ R ¹⁶ , or -CH ₂ X; q is 0, 1, 2, 3, or 4; and n is 0, 1, or 2, or a pharmaceutically-acceptable salt thereof.

In some embodiments, the calcium channel modulator is represented by the following structure: wherein n is 0, 1, or 2; q is 0, 1, 2, 3, or 4; R' and R" are each independently acyl, alkyl, alkoxyl, alkylamino, alkylthio, cycloalkyl, aryl, heterocyclyl, heterocyclylalkyl, alkenyl, alkynyl, aryl, heteroaryl, arylthiol, heteroarylthio, arylamino, or heteroarylamino, each of which is independently substituted or substituted; or halogen, H, -OH, -NH ₂ , -NO ₂ , -CN, -CF ₃ , -OCF ₃ , -N ₃ , -SO ₃ H, -S(=O) ₂ alkyl, -S(=O)alkyl, or -OS(=O) ₂ CF ₃ ; and

R ⁸ and R ⁹ are each independently acyl, alkenyl, alkoxyl, alkyl, alkylamino, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or OH, or a pharmaceutically-acceptable salt thereof.

In some embodiments, the calcium channel modulator is represented by the following structure: wherein:

R ^d is CH ₂ , or NR ^a ; and

R ^a is H, alkoxy, -(C ₁ -C ₆ alkyl)-aryl, wherein the aryl is a disubstituted phenyl or a benzo[l,3]dioxo-5-yl group, or a Boc group. or a pharmaceutically-acceptable salt thereof.

In some embodiments, R ^a is H.

In some embodiments, the calcium channel modulator is represented by the following structure: wherein:

R ^e is -(C ₁ -C ₆ alkyl)-phenyl, -(C ₁ -C ₆ alkyl)-C(O)R ^b , or substituted or unsubstituted -C ₁ - C ₆ alkyl; and R ^b is -OH or -O-(C ₁ -C ₆ alkyl), wherein the phenyl or the substituted alkyl is substituted with one or more of halogen, hydroxyl, -C ₁ -C ₆ alkyl, -O-(C ₁ -C ₆ alkyl), -NH ₂ , -NH(C ₁ -C ₆ alkyl), -N(C ₁ -C ₆ alkyl) ₂ , cyano, or dioxolane, or a pharmaceutically-acceptable salt thereof.

In some embodiments, the calcium channel modulator is represented by the following structure: wherein:

R ^c is -(C ₁ -C ₆ alkyl)-NH ₂ , -(C ₁ -C ₆ alkyl)-OR ^f , wherein R _f is H or -C(O)-(C ₁ -C ₆ )alkyl, or -(C ₁ -C ₆ alkyl)-NHR ^g , wherein R ⁸ is carboxybenzyl.

In some embodiments, the calcium channel modulator is represented by the following structure: wherein: n is 0, 1, or 2; q is 0, 1, 2, 3, or 4; each R is independently acyl, -O-acyl, alkyl, alkoxyl, alkylamino, alkylarylamino, alkylthio, cycloalkyl, alkylaryl, aryl, heteroaryl, heterocyclyl, heterocyclylalkyl, alkenyl, alkynyl, arylthio, arylamino, heteroarylthio, or heteroarylamino, each of which is independently substituted or unsubstituted; or halogen, -OH, -NH ₂ , -NO ₂ , -CN, -CF ₃ , -OCF ₃ , -N ₃ , -SO ₃ H, - S(=O) ₂ alkyl, -S(=O)alkyl, or -OS(=O) ₂ CF ₃ ; each R ² and R ^2a is independently alkyl, aryl, alkylaryl, heteroaryl, cycloalkyl, cycloalkylalkyl, or heterocyclyl, each of which is independently substituted or unsubstituted; or H, -C(=O)R ⁵ , -C(=S)R ⁶ , -SO ₂ R ⁷ , -P(=O)R ⁸ R ⁹ , or -(CH ₂ )m-R ¹⁰ ; each R ⁵ is acyl, alkyl, alkenyl, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or -NR ¹⁵ R ¹⁶ , -NHNR ¹⁵ R ¹⁶ , -NHOH, -OR ¹⁵ , -C(=O)NHNR ¹⁵ R ¹⁶ , -CO ₂ R ¹⁵ , - C(=O)NR ¹⁵ R ¹⁶ , -CH ₂ X, or alkyl substituted by at least one labeling group, selected from a fluorescent group, a bioluminescent group, a chemiluminescent group, a colorimetric group, and a radioactive labeling group; each R ⁶ is acyl, alkenyl, alkyl, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or -OR ¹⁵ , -NHNR ¹⁵ R ¹⁶ , -NHOH, -NR ¹⁵ R ¹⁶ , or -CH ₂ X; each R ⁷ is alkyl, alkenyl, alkynyl, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or -OR ¹⁵ , -NR ¹⁵ R ¹⁶ , -NHNR ¹⁵ R ¹⁶ , -NHOH, or -CH ₂ X; each R ⁸ and R ⁹ are each independently acyl, alkenyl, alkoxyl, alkyl, alkylamino, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or OH; each R ¹⁰ is -NR ¹⁵ R ¹⁶ , OH, -SO ₂ R ¹¹ , -NHSO ₂ R ¹¹ , -C(=O)R ¹² , -NH(C=O)R ¹² , -O(C=O)R ¹² , or -P(=O)R ¹³ R ¹⁴ ; m is 0, 1, 2, 3, or 4; each R ¹¹ , R ¹² , R ¹³ , and R ¹⁴ is independently acyl, alkenyl, alkoxyl, alkyl, alkylamino, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or H, OH, NH ₂ , -NHNH ₂ , or -NHOH; each X is halogen, -CN, -CO ₂ R ¹⁵ , -C(=O)NR ¹⁵ R ¹⁶ , -NR ¹⁵ R ¹⁶ , -OR ¹⁵ , -SO ₂ R ⁷ , or - P(=O)R ⁸ R ⁹ ; and each R ¹⁵ and R ¹⁶ is independently acyl, alkenyl, alkoxyl, OH, NH ₂ , alkyl, alkylamino, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted, or H; or R ¹⁵ and R ¹⁶ together with the N to which R ¹⁵ and R ¹⁶ are bonded form a heterocycle that is substituted or unsubstituted; or a pharmaceutically-acceptable salt thereof. In some embodiments, the calcium channel modulator is represented by the following structure: or a pharmaceutically-acceptable salt thereof, wherein each R ^1a , R ^1b , R ^1c , and R ^1d is independently alkyl, haloalkyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heteroaryl, heterocyclyl, -CN, -NO ₂ , -N ₃ , -NR ³ R ⁴ , -OR ⁵ , -SO ₃ H, - SO ₂ R ⁶ , -OSO ₂ R ⁶ , -S(O)R ⁶ , or -SR ⁷ , each of which is independently substituted or unsubstituted, or hydrogen or halogen,

R ² is alkyl, haloalkyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heteroaryl, heterocyclyl, -C(O)NR ³ R ⁴ , -C(O)C(O)NR ³ R ⁴ , -C(O)R ⁸ , -C(O)OR ⁸ , or -C(O)C(O)OR ⁸ , each of which is independently substituted or unsubstituted, each R ³ and R ⁴ is independently alkyl, haloalkyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heteroaryl, or heterocyclyl, each of which is independently substituted or unsubstituted, or hydrogen or halogen; or R ³ and R ⁴ together with the nitrogen atom to which R ³ and R ⁴ are attached form a heterocyclic or heteroaromatic ring, which is unsubstituted or substituted, and each R ⁵ , R ⁶ , R ⁷ , and R ⁸ is independently alkyl, haloalkyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heteroaryl, or heterocyclyl, each of which is independently substituted or unsubstituted, or hydrogen or halogen.

In some embodiments, R ² is -C(O)NR ³ R ⁴ , and the calcium channel modulator is represented by the following structure:

wherein

- each R ^1a , R ^1b , R ^1c , and R ^1d is independently alkyl, haloalkyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heteroaryl, heterocyclyl, -CN, -NO ₂ , -N ₃ , -NR ³ R ⁴ , -OR ⁵ , -SO ₃ H, - SO ₂ R ⁶ , -OSO ₂ R ⁶ , -S(O)R ⁵ , or -SR ⁷ , each of which is independently substituted or unsubstituted, or hydrogen or halogen;

- each R ³ and R ⁴ is independently alkyl, haloalkyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heteroaryl, or heterocyclyl, each of which is independently substituted or unsubstituted, or hydrogen or halogen; or R ³ and R ⁴ together with the nitrogen atom to which R ³ and R ⁴ are attached form a heterocyclic or heteroaromatic ring, which is unsubstituted or substituted; and

- each R ⁵ , R ⁶ , and R ⁷ is independently alkyl, haloalkyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heteroaryl, or heterocyclyl, each of which is independently substituted or unsubstituted, or hydrogen or halogen; or a pharmaceutically-acceptable salt thereof

In some embodiments, the calcium channel modulator is represented by the following structure: wherein each R ^1a , R ^1b , R ^1c , and R ^1d is independently alkyl, haloalkyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heteroaryl, heterocyclyl, -CN, -NO ₂ , -N ₃ , -NR ³ R ⁴ , -OR ⁵ , -SO ₃ H, - SO ₂ R ⁶ , -OSO ₂ R ⁶ , -S(O)R ⁶ , or -SR ⁷ , each of which is independently substituted or unsubstituted, or hydrogen or halogen; each R ³ and R ⁴ is independently alkyl, haloalkyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heteroaryl, or heterocyclyl, each of which is independently substituted or unsubstituted, or hydrogen or halogen; or R ³ and R ⁴ together with the nitrogen atom to which R ³ and R ⁴ are attached form a heterocyclic or heteroaromatic ring, which is unsubstituted or substituted; each R ⁵ , R ⁶ , and R ⁷ is independently alkyl, haloalkyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heteroaryl, or heterocyclyl, each of which is independently substituted or unsubstituted, or hydrogen or halogen;

R ⁹ is alkyl, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heterocyclyl, heteroaryl, -C(O)NR ³ R ⁴ . - C(O)R ⁸ , or -C(O)OR ⁸ , each of which is independently substituted or unsubstituted, or hydrogen; each R ¹⁰ is independently alkyl, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heterocyclyl, heteroaryl, -NR ³ R ⁴ , -OR ⁵ , or -SR ⁷ , each of which is unsubstituted or substituted; and m is 0, 1, 2, 3, 4, 5, 6, 7, or 8; or a pharmaceutically- acceptable salt thereof.

In some embodiments, the calcium channel modulator is represented by the following structure: wherein each R ^1a , R ^1b , R ^1c , and R ^1d is independently alkyl, haloalkyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heteroaryl, heterocyclyl, -CN, -NO ₂ , -N ₃ , -NR ³ R ⁴ , -OR ⁵ , -SO ₃ H, - SO ₂ R ⁶ , -OSO ₂ R ⁶ , -S(O)R ⁶ , or -SR ⁷ , each of which is independently substituted or unsubstituted, or hydrogen or halogen; each R ³ and R ⁴ is independently alkyl, haloalkyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heteroaryl, or heterocyclyl, each of which is independently substituted or unsubstituted, or hydrogen or halogen; or R ³ and R ⁴ together with the nitrogen atom to which R ³ and R ⁴ are attached form a heterocyclic or heteroaromatic ring, which is unsubstituted or substituted; each R ⁵ , R ⁶ , and R ⁷ is independently alkyl, haloalkyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heteroaryl, or heterocyclyl, each of which is independently substituted or unsubstituted, or hydrogen or halogen; or a pharmaceutically-acceptable salt thereof.

In some embodiments, the calcium channel modulator is represented by the following structure: wherein each R ¹ is independently halogen, haloalkyl, haloalkyloxy; and n is 1, 2, 3, or 4; or a pharmaceutically-acceptable salt thereof.

In some embodiments, n is 1 and R ¹ is at position 6 of the benzothiazepine ring, and the calcium channel modulator is represented by the following structure: or a pharmaceutically-acceptable salt thereof.

In some embodiments, n is 1 and R ¹ is at position 7 of the benzothiazepine ring, and the calcium channel modulator is represented by the following structure: or a pharmaceutically-acceptable salt thereof.

In some embodiments, n is 1, and R ¹ is at position 8 of the benzothiazepine ring, and the calcium channel modulator is represented by the following structure: or a pharmaceutically-acceptable salt thereof.

In some embodiments, n is 1, R ¹ is at position 9 of the benzothiazepine ring, and the calcium channel modulator is represented by the following structure: or a pharmaceutically-acceptable salt thereof.

In some embodiments, n is 2, R ¹ is at positions 7 and 8 of the benzothiazepine ring, and the calcium channel modulator is represented by the following structure: or a pharmaceutically-acceptable salt thereof. In some embodiments, the calcium channel modulator is represented by the following structure below that is piperazin-1-yl(8-(trifluoromethyl)-2,3-dihydrobenzo[f][1,4]t hiazepin-4(5H)- yl)methanone), or a pharmaceutically-acceptable salt thereof. In some embodiments, the pharmaceutically-acceptable salt is a hydrochloride salt.

In some embodiments, the calcium channel modulator is represented by the following structure below that is piperazin-1-yl(7-(trifluoromcthyl)-2,3-dihydrobenzo[f][1,4]t hiazcpin-4(5H)- yl) methanone), or a pharmaceutically-acceptable salt thereof. In some embodiments, the pharmaceutically- acceptable salt is a hydrochloride salt.

In some embodiments, the calcium channel modulator is represented by the following structure below that is piperazin-1-yl(9-(trifluoromethyl)-2,3-dihydrobenzo[f][1,4]t hiazepin-4(5H)- yl)methanone), or a pharmaceutically-acceptable salt thereof. In some embodiments, the pharmaceutically-acceptable salt is a hydrochloride salt.

In some embodiments, the calcium channel modulator is represented by the following structure below that is piperazin-1-yl(7-(trifluoromethoxy)-2,3-dihydrobenzo[f][1,4] thiazepin- 4(5H)-yl)methanone), or a pharmaceutically-acceptable salt thereof. In some embodiments, the pharmaceutically-acceptable salt is a hydrochloride salt.

In some embodiments, the calcium channel modulator is represented by the following structure below that is piperazin-1-yl(6-(trifluoromethyl)-2,3-dihydrobenzo[f][1,4]t hiazepin-4(5H)- yl)methanone), or a pharmaceutically-acceptable salt thereof. In some embodiments, the pharmaceutically-acceptable salt is a hydrochloride salt.

In some embodiments, the calcium channel modulator is represented by the following structure below that is (7,8-difluoro-2,3-dihydrobenzo[f][1,4]thiazepin-4(5H)-yl)(pi perazin-1- yl)methanone), or a pharmaceutically-acceptable salt thereof. In some embodiments, the pharmaceutically-acceptable salt is a hydrochloride salt.

In some embodiments, the calcium channel modulator is represented by the following structure below that is (6-chloro-2,3-dihydrobenzo[f][1,4]thiazepin-4(5H)-yl)(pipera zin-1- yl)methanone), or a pharmaceutically-acceptable salt thereof. In some embodiments, the pharmaceutically-acceptable salt is a hydrochloride salt.

In some embodiments, the calcium channel modulator is represented by the following structure below that is piperazin-1-yl(6-(trifluoromethoxy)-2,3-dihydrobenzo[f][1,4] thiazepin- 4(5H)-yl)methanone), or a pharmaceutically-acceptable salt thereof. In some embodiments, the pharmaceutically-acceptable salt is a hydrochloride salt.

In some embodiments, the calcium channel modulator is represented by the following structure below that is (6-bromo-2,3-dihydrobenzo[f][1,4]45hiazepine-4(5H)-yl)(piper azin-1- yl)methanone), or a pharmaceutically-acceptable salt thereof. In some embodiments, the pharmaceutically-acceptable salt is a hydrochloride salt.

In some embodiments, the calcium channel modulator is represented by the following structure below that is (6-iodo-2,3-dihydrobenzo[f][1,4]thiazepin-4(5H)-yl)(piperazi n-1- yl)methanone), or a pharmaceutically-acceptable salt thereof. In some embodiments, the pharmaceutically-acceptable salt is a hydrochloride salt.

In some embodiments, the compound is selected from:

Pharmaceutically-Acceptable Salts

The disclosure provides the use of pharmaceutically-acceptable salts of any therapeutic compound described herein. Pharmaceutically-acceptable salts include, for example, acidaddition salts and base-addition salts. The acid that is added to the compound to form an acidaddition salt can be an organic acid or an inorganic acid. A base that is added to the compound to form a base-addition salt can be an organic base or an inorganic base. In some embodiments, a pharmaceutically-acceptable salt is a metal salt. In some embodiments, a pharmaceutically- acceptable salt is an ammonium salt.

Metal salts can arise from the addition of an inorganic base to a compound of the disclosure. The inorganic base consists of a metal cation paired with a basic counterion, such as, for example, hydroxide, carbonate, bicarbonate, or phosphate. The metal can be an alkali metal, alkaline earth metal, transition metal, or main group metal. In some embodiments, the metal is lithium, sodium, potassium, cesium, cerium, magnesium, manganese, iron, calcium, strontium, cobalt, titanium, aluminum, copper, cadmium, or zinc.

In some embodiments, a metal salt is a lithium salt, a sodium salt, a potassium salt, a cesium salt, a cerium salt, a magnesium salt, a manganese salt, an iron salt, a calcium salt, a strontium salt, a cobalt salt, a titanium salt, an aluminum salt, a copper salt, a cadmium salt, or a zinc salt.

Ammonium salts can arise from the addition of ammonia or an organic amine to a compound of the present disclosure. In some embodiments, the organic amine is triethyl amine, diisopropyl amine, ethanol amine, diethanol amine, triethanol amine, morpholine, N- methylmorpholine, piperidine, N-methylpiperidine, N-ethylpiperidine, dibenzylamine, piperazine, pyridine, pyrazole, imidazole, or pyrazine. In some embodiments, an ammonium salt is a triethyl amine salt, a trimethyl amine salt, a diisopropyl amine salt, an ethanol amine salt, a dicthanol amine salt, a tricthanol amine salt, a morpholine salt, an N-methylmorpholine salt, a piperidine salt, an N-methylpiperidine salt, an N- ethylpiperidine salt, a dibenzylamine salt, a piperazine salt, a pyridine salt, a pyrazole salt, a pyridazine salt, a pyrimidine salt, an imidazole salt, or a pyrazine salt.

Acid addition salts can arise from the addition of an acid to a compound of the present disclosure. In some embodiments, the acid is organic. In some embodiments, the acid is inorganic. In some embodiments, the acid is hydrochloric acid, hydrobromic acid, hydroiodic acid, nitric acid, nitrous acid, sulfuric acid, sulfurous acid, a phosphoric acid, isonicotinic acid, lactic acid, salicylic acid, tartaric acid, ascorbic acid, gentisic acid, gluconic acid, glucuronic acid, saccharic acid, formic acid, benzoic acid, glutamic acid, pantothenic acid, acetic acid, trifluoroacetic acid, mandelic acid, cinnamic acid, aspartic acid, stearic acid, palmitic acid, glycolic acid, propionic acid, butyric acid, fumaric acid, succinic acid, methanesulfonic acid, ethanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, citric acid, oxalic acid, or maleic acid.

In some embodiments, the salt is a hydrochloride salt, a hydrobromide salt, a hydroiodide salt, a nitrate salt, a nitrite salt, a sulfate salt, a sulfite salt, a phosphate salt, isonicotinate salt, a lactate salt, a salicylate salt, a tartrate salt, an ascorbate salt, a gentisate salt, a gluconate salt, a glucuronate salt, a saccharate salt, a formate salt, a benzoate salt, a glutamate salt, a pantothenate salt, an acetate salt, a trifluoroacetate salt, a mandelate salt, a cinnamate salt, an aspartate salt, a stearate salt, a palmitate salt, a glycolate salt, a propionate salt, a butyrate salt, a fumarate salt, a hemifumarate salt, a succinate salt, a methanesulfonate salt, an ethanesulfonate salt, a benzenesulfonate salt, a p-toluenesulfonate salt, a citrate salt, an oxalate salt, or a maleate salt.

Pharmaceutical Compositions

The compounds described herein can be administered neat or as pharmaceutical compositions for administration to human or animal subjects in a biologically-compatible form suitable for administration in vivo. Subjects can be, for example, elderly adults, adults, adolescents, pre-adolescents, children, toddlers, infants, neonates, and non-human animals. In some embodiments, a subject is a patient. Compounds administered according to the methods of the disclosure can be formulated into pharmaceutical compositions for administration to human subjects in a biologically compatible form suitable for administration in vivo. In some embodiments, provided is a pharmaceutical composition comprising compounds disclosed herein in admixture with a pharmaceutically-acceptable excipient, diluent and/or carrier. The pharmaceutically-acceptable carrier is preferably acceptable in the sense of being compatible with the other ingredients of the composition and not deleterious to the recipient thereof.

Non-limiting examples of routes of administration include oral, sublingual, buccal, parenteral (intravenous, intramuscular or subcutaneous), transdermal, per- or trans-cutaneous, intranasal, intra-vaginal, rectal, ocular, and respiratory (via inhalation administration). In some embodiments, the compounds are administered directly into the CNS, for example by intralumbar injection or intraventricular infusion of the compounds directly into the cerebrospinal-fluid (CSF), or by intraventricular, intrathecal or interstitial administration. Administration can be to the subject’s muscles, for example, the subject’s cardiac or skeletal muscles. In some embodiments, the compound is administered to the subject by targeted delivery to cardiac muscle cells via a catheter inserted into the subject's heart. In some embodiments, the compound is orally administered.

Pharmaceutical compositions for solid oral administration include tablets or dragees, sublingual tablets, gastro-resistant tablets, sachets, capsules including gelatin capsules, powders, and granules. Those for liquid oral, nasal, buccal, or ocular administration include emulsions, solutions, suspensions, drops, syrups, and aerosols. The compounds can also be administered as a suspension or solution via drinking water or with food.

Non-limiting examples of pharmaceutically-acceptable excipients or carriers include organic or inorganic materials that are used as materials for pharmaceutical formulations and are incorporated as any one or more of fillers, diluents, binders, disintegrants, buffers (pH adjusting agents), colorants, emulsifiers, flavor-improving agents, gellants, glidants, surfactants (wetting agents), preservatives, solubilizers, stabilizers, suspending agents, sweeteners, tonicity agents, emulsifiers, dispersing agents, swelling agents, retardants, lubricants, absorbents, plasticizers, and viscosity-increasing agents.

Non-limiting examples of pharmaceutically-acceptable fillers/diluents include cellulose derivatives including microcrystalline cellulose, silicified microcrystalline cellulose carboxymethyl cellulose, methyl cellulose, hydroxypropyl cellulose, hydroxypropyl mcthylccllulosc, ethyl cellulose, starches, sugars such as mannitol, sucrose, lactose, sorbitol, dextrins (e.g., maltodextrin), amino-sugars, alginic acid, sodium alginate, and water.

Non-limiting examples of pharmaceutically-acceptable binders include microcrystalline cellulose, gum tragacanth, gum arabic, gelatin, polyvinylpyrrolidone, copovidone, hydroxypropyl methylcellulose, and starch.

Non-limiting examples of pharmaceutically-acceptable disintegrants include croscarmellose sodium, sodium carboxymethyl starch, and crospovidone.

Non-limiting examples of pharmaceutically-acceptable lubricants include stearates such as magnesium stearate or zinc stearate, stearic acid, sodium stearyl fumarate, talc, glyceryl behenate, sodium lauryl sulfate, polyethylene glycol, and hydrogenated vegetable oil.

Non-limiting examples of pharmaceutically-acceptable glidants include colloidal silicon dioxide, talc, tribasic calcium phosphate, calcium silicate, cellulose, magnesium silicate, magnesium trisilicate, starch, magnesium stearate, talc, and mineral oil. Non-limiting examples of moisture barrier agents include stearic acid.

Non-limiting examples of pharmaceutically-acceptable plasticizers include triethyl citrate.

Non-limiting examples of pharmaceutically-acceptable surfactants include sodium laurylsulfate or polysorbates, polyvinyl alcohol (PVA), polyethylene glycols, polyoxyethylenepolyoxypropylene block copolymers known as “poloxamer”, polyglycerin fatty acid esters such as decaglyceryl monolaurate and decaglyceryl monomyristate, sorbitan fatty acid ester such as sorbitan monostearate, polyoxyethylene sorbitan fatty acid ester such as polyoxyethylene sorbitan monooleate (Tween), polyethylene glycol fatty acid ester such as polyoxyethylene monostearate, polyoxyethylene alkyl ether such as polyoxyethylene lauryl ether, polyoxyethylene castor oil, and hardened castor oil such as polyoxyethylene hardened castor oil.

Non-limiting examples of pharmaceutically-acceptable flavoring agents include sweeteners such as sucralose and synthetic flavor oils and flavoring aromatics, natural oils, extracts from plants, leaves, flowers, and fruits, and combinations thereof. Non-limiting examples of flavoring agents include cinnamon oils, oil of wintergreen, peppermint oils, clover oil, hay oil, anise oil, eucalyptus, peppermint, vanilla, citrus oil such as lemon oil, orange oil, grape and grapefruit oil, and fruit essences including apple, peach, pear, strawberry, raspberry, cherry, plum, pineapple, and apricot.

Non-limiting examples of pharmaceutically-acceptable pigments or colorants include alumina (dried aluminum hydroxide), annatto extract, calcium carbonate, canthaxanthin, caramel, 0-carotene, cochineal extract, carmine, potassium sodium copper chlorophyllin (chlorophyllin-copper complex), dihydroxy acetone, bismuth oxychloride, synthetic iron oxide, ferric ammonium ferrocyanide, ferric ferrocyanide, chromium hydroxide green, chromium oxide greens, guanine, mica-based pearlescent pigments, pyrophyllite, mica, dentifrices, talc, titanium dioxide, aluminum powder, bronze powder, copper powder, and zinc oxide.

Non-limiting examples of buffering or pH adjusting agents include acidic buffering agents such as short chain fatty acids, citric acid, acetic acid, hydrochloric acid, sulfuric acid and fumaric acid; and basic buffering agents such as tris, sodium carbonate, sodium bicarbonate, sodium hydroxide, potassium hydroxide, and magnesium hydroxide.

Non-limiting examples of tonicity enhancing agents include ionic and non-ionic agents such as, alkali metal or alkaline earth metal halides, urea, glycerol, sorbitol, mannitol, propylene glycol, and dextrose.

Non-limiting examples of wetting agents include glycerin, cetyl alcohol, and glycerol monostearate.

Non-limiting examples of preservatives include benzalkonium chloride, benzoxonium chloride, thiomersal, phenylmercuric nitrate, phenylmercuric acetate, phenylmercuric borate, methylparaben, propylparaben, chlorobutanol, benzyl alcohol, phenyl alcohol, chlorohexidine, and polyhexamethylene biguanide.

Non-limiting examples of antioxidants include sorbic acid, ascorbic acid, ascorbate, glycine, α-tocopherol, butylated hydroxyanisole (BHA), and butylated hydroxytoluene (BHT).

In some embodiments, solid dosage forms are coated. In some embodiments, solid dosage forms contain a core, a subcoating layer substantially surrounding the core, and a coating layer substantially surrounding the subcoating layer.

In some embodiments, the subcoating layer comprises a swellable polymer such as a swellable hydrophobic polymer layer (e.g., hydroxypropyl cellulose (HPC) or hydroxypropylmethyl cellulose (HPMC). In some embodiments, the coating layer comprises an enteric polymer. Non-limiting examples of enteric polymers include hydroxypropyl mcthylccllulosc acetate succinate (hypromellose acetate succinate, HPMC-AS), cellulose acetate phthalate, hydroxypropyl methylcellulose phthalate, cellulose acetate trimellitate, polyvinyl acetate phthalate, methacrylic acid/methacrylic acid ester copolymers (e.g., poly (methacrylic acid-co-methyl methacrylate), methacrylic acid/acrylic acid ester copolymers, shellac (esters of aleurtic acid).

In some embodiments, pharmaceutically-acceptable carriers or excipients are used to formulate liquids, gels, syrups, elixirs, slurries, or suspensions for oral ingestion by a subject. Non-limiting examples of solvents used in an oral dissolvable formulation can include water, ethanol, isopropanol, saline, physiological saline, DMSO, potassium phosphate buffer, phosphate buffer saline (PBS), sodium phosphate buffer, 4-2-hydroxyethyl-1-piperazineethanesulfonic acid buffer (HEPES), 3-(N-morpholino)propanesulfonic acid buffer (MOPS), piperazine-N,N'-bis(2- ethanesulfonic acid) buffer (PIPES), and saline sodium citrate buffer (SSC). Non-limiting examples of co-solvents used in an oral dissolvable formulation can include sucrose, urea, cremaphor, and potassium phosphate buffer.

Pharmaceutical compositions for parenteral injections can include sterile solutions, which can be aqueous or non-aqueous, dispersions, suspensions, emulsions, and also sterile powders for the reconstitution of injectable solutions or dispersions. The compounds can be combined with a sterile aqueous solution that is isotonic with the blood of the subject. A parenteral formulation can be prepared by dissolving a solid active ingredient in water containing physiologically- compatible substances, such as sodium chloride or glycine, and having a buffered pH compatible with physiological conditions, to produce an aqueous solution, then rendering the solution sterile. The formulation is presented in unit or multi-dose containers, such as sealed ampoules or vials. The formulation is delivered by any mode of injection, including, without limitation, epifascial, intracapsular, intracranial, intracutaneous, intrathecal, intramuscular, intraorbital, intraperitoneal, intraspinal, intrasternal, intravascular, intravenous, parenchymatous, subcutaneous, or sublingual or by catheter into the subject's heart.

Pharmaceutical compositions for rectal or vaginal administration can be suppositories, and those for per- or trans-cutaneous administration include powders, aerosols, creams, ointments, gels, and patches. For transdermal administration, the compounds can be combined with skin penetration enhancers, such as propylene glycol, polyethylene glycol, isopropanol, ethanol, oleic acid, or N- methylpyrrolidone. These agents increase the permeability of the skin and permit compounds to penetrate through the skin and into the bloodstream. The compound/enhancer compositions can be further combined with a polymeric substance, such as ethylcellulose, hydroxypropyl cellulose, ethylene/vinylacetate, or polyvinyl pyrrolidone to provide the composition in gel form, which is dissolved in a solvent, evaporated to the desired viscosity, and then applied to backing material to provide a patch.

Pharmaceutical formulations of the present disclosure can be prepared by methods such as wet granulation, dry granulation, or direct compression.

A pharmaceutically-acceptable excipient can be present in a pharmaceutical composition at a mass of between about 0.1% and about 99% by mass of the composition. For example, a pharmaceutically-acceptable excipient can be present in a pharmaceutical composition at a mass of between about 0.1% and about 95%, between about 0.11% and about 90%, between about 0.1% and about 85%, between about 0.1% and about 80%, between about 0.1% and about 75%, between about 0.1% and about 70%, between about 0.1% and about 65%, between about 0.1% and about 60%, between about 0.1% and about 55%, between about 0.1% and about 50%, between about 0.1% and about 45%, between about 0.11% and about 40%, between about 0.1% and about 35%, between about 0.1% and about 30%, between about 0.1% and about 25%, between about 0.1% and about 20%, between about 0.1% and about 15%, between about 0.1% and about 10%, between about 0.1% and about 5%, between about 0.1% and about 1%, by mass of the formulation.

A pharmaceutically-acceptable excipient can be present at about 0.1%, about 0.2%, about 0.3%, about 0.4%, about 0.5%, about 0.6%, about 0.7%, about 0.8%, about 0.9%, about 1%, about 2%, about 3%, about 4%, about 5%, about 6%, about 7%, about 8%, about 9%, about 10%, about 11%, about 12%, about 13%, about 14%, about 15%, about 16%, about 17%, about 18%, about 19%, about 20%, about 21%, about 22%, about 23%, about 24%, about 25%, about 26%, about 27%, about 28%, about 29%, about 30%, about 31%, about 32%, about 33%, about 34%, about 35%, about 36%, about 37%, about 38%, about 39%, about 40%, about 41%, about 42%, about 43%. about 44%, about 45%, about 46%, about 47%, about 48%, about 49%, about 50%, about 51%, about 52%, about 53%, about 54%, about 55%, about 56%, about 57%, about 58%, about 59%, about 60%, about 61 %, about 62%, about 63%, about 64%, about 65%, about 66%, about 67%, about 68%, about 69%, about 70%, about 71%, about 72%, about 73%, about 74%, about 75%, about 76%, about 77%, about 78%, about 79%, about 80%, about 81%, about 82%, about 83%, about 84%, about 85%, about 86%, about 87%, about 88%, about 89%, about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%, about 98%. about 99%, about 99.1%, about 99.2%, about 99.3%, about 99.4%, about 99.5%, about 99.6%, about 99.7%, about 99.8%, or about 99.9% by mass of the formulation.]

Dosing and Dosing Regimens

In accordance with the methods of the present disclosure, any of these compounds can be administered to the subject (or contacted with cells of the subject) in an amount effective to repair calcium leak in the subject, particularly in cells of the subject. Alternatively, the methods of the present disclosure comprise administering a compound in an amount effective to treat or prevent a condition as described herein.

In some embodiments, a suitable amount of the compounds can range from about 1 to about 2,000 mg per day, for example about 50 mg per day, about 75 mg per day, about 100 mg per day, about 110 mg per day, about 120 mg per day, about 130 mg per day, about 140 mg per day, about 150 mg per day, about 160 mg per day, about 170 mg per day, about 180 mg per day, about 190 mg per day, about 200 mg per day, about 210 mg per day, about 220 mg per day, about 230 mg per day, about 240 mg per day, about 250 mg per day, about 260 mg per day, about 270 mg per day, about 280 mg per day, about 290 mg per day, about 300 mg per day, about 310 mg per day, about 320 mg per day, about 330 mg per day, about 340 mg per day, about 350 mg per day, about 360 mg per day, about 370 mg per day, about 380 mg per day, about 390 mg per day, about 400 mg per day, about 410 mg per day, about 420 mg per day, about 430 mg per day, about 440 mg per day, about 450 mg per day, about 460 mg per day, about 470 mg per day, about 480 mg per day, about 450 mg per day, about 500 mg per day, about 600 mg per day, about 700 mg per day, about 800 mg per day, about 900 mg per day, about 1,000 mg per day, about 1,100 mg per day, about 1,200 mg per day, about 1,300 mg per day, about 1 ,400 mg per day, about 1 ,500 mg per day, about 1 ,600 mg per day, about 1 ,700 mg per day, about 1,800 mg per day, about 1,900 mg per day, or about 2,000 mg per day. A compound described herein can be present in a composition in a range of from about 1 mg to about 2000 mg; from about 1 mg to about 1000 mg; from about 1 mg to about 500 mg; from about 5 mg to about 1000 mg, from about 5 mg to about 500 mg, from about 5 mg to about 100 mg, from about 10 mg to about 50 mg, from about 50 mg to about 250 mg, from about 100 mg to about 200 mg, from about 1 mg to about 50 mg, from about 50 mg to about 100 mg, from about 100 mg to about 150 mg, from about 150 mg to about 200 mg, from about 200 mg to about 250 mg, from about 250 mg to about 300 mg, from about 300 mg to about 350 mg, from about 350 mg to about 400 mg, from about 400 mg to about 450 mg, from about 450 mg to about 500 mg, from about 500 mg to about 550 mg, from about 550 mg to about 600 mg, from about 600 mg to about 650 mg, from about 650 mg to about 700 mg, from about 700 mg to about 750 mg, from about 750 mg to about 800 mg, from about 800 mg to about 850 mg, from about 850 mg to about 900 mg, from about 900 mg to about 950 mg, or from about 950 mg to about 1000 mg.

A compound described herein can be present in a composition in an amount of about 1 mg, about 2 mg, about 3 mg, about 4 mg, about 5 mg, about 10 mg, about 15 mg, about 20 mg, about 25 mg, about 30 mg, about 35 mg, about 40 mg, about 45 mg, about 50 mg, about 55 mg, about 60 mg, about 65 mg, about 70 mg, about 75 mg, about 80 mg, about 85 mg, about 90 mg, about 95 mg, about 100 mg, about 100 mg, about 125 mg, about 150 mg, about 175 mg, about 200 mg, about 250 mg, about 300 mg, about 350 mg, about 400 mg, about 450 mg, about 500 mg, about 550 mg, about 600 mg, about 650 mg, about 700 mg, about 750 mg, about 800 mg, about 850 mg, about 900 mg, about 950 mg, about 1000 mg, about 1050 mg, about 1100 mg, about 1150 mg, about 1200 mg, about 1250 mg, about 1300 mg, about 1350 mg, about 1400 mg, about 1450 mg, about 1500 mg, about 1550 mg, about 1600 mg, about 1650 mg, about 1700 mg, about 1750 mg, about 1800 mg, about 1850 mg, about 1900 mg, about 1950 mg, or about 2000 mg.

In some embodiments, a dose can be expressed in terms of an amount of the drug divided by the mass of the subject, for example, milligrams of drug per kilograms of subject body mass. In some embodiments, a compound is administered in an amount ranging from about 0.01 mg/kg to about 2,000 mg/kg, about 0.01 mg/kg to about 1,000 mg/kg, about 0.01 mg/kg to about 100 mg/kg, about 0.01 mg/kg to about 10 mg/kg, about 0.01 mg/kg to about 5 mg/kg, about 0.01 mg/kg to about 1 mg/kg, about 0.01 mg/kg to about 0.5 mg/kg, about 0.01 mg/kg to about 0.1 mg/kg, about 0.01 mg/kg to about 0.05 mg/kg, about 1 mg/kg to about 1,000 mg/kg, about 1 mg/kg to about 500 mg/kg, about 1 mg/kg to about 250 mg/kg, about 1 mg/kg to about 100 mg/kg, about 1 mg/kg to about 50 mg/kg, about 5 mg/kg to about 50 mg/kg, about 5 mg/kg to about 10 mg/kg, about 5 mg/kg to about 20 mg/kg, about 10 mg/kg to about 50 mg/kg, about 10 mg/kg to about 20 mg/kg, about 250 mg/kg to about 2000 mg/kg, about 10 mg/kg to about 800 mg/kg, about 50 mg/kg to about 400 mg/kg, about 100 mg/kg to about 300 mg/kg, or about 150 mg/kg to about 200 mg/kg. In some embodiments, a compound is administered in an amount of about 1 mg/kg, about 2 mg/kg, about 5 mg/kg, about 10 mg/kg, about 20 mg/kg, about 50 mg/kg, about 100 mg/kg, about 150 mg/kg, about 200 mg/kg, about 250 mg/kg, about 300 mg/kg, about 350 mg/kg, about 400 mg/kg, about 450 mg/kg, about 500 mg/kg, about 550 mg/kg, about 600 mg/kg, about 650 mg/kg, about 700 mg/kg, about 750 mg/kg, about 800 mg/kg, about 850 mg/kg, about 900 mg/kg, about 950 mg/kg or about 1,000 mg/kg of subject body mass.

In some embodiments, a dose can be expressed in terms of an amount of the drug divided by the mass of the subject per day, for example, milligrams of drug per kilograms of subject body mass, per day (mg/kg/day/day). In some embodiments, a compound is administered in an amount ranging from about 0.01 mg/kg/day to about 2,000 mg/kg/day, about 0.01 mg/kg/day to about 1,000 mg/kg/day, about 0.01 mg/kg/day to about 100 mg/kg/day, about 0.01 mg/kg/day to about 10 mg/kg/day, about 0.01 mg/kg to about 5 mg/kg/day, about 0.01 mg/kg/day to about 1 mg/kg/day, about 0.01 mg/kg/day to about 0.5 mg/kg/day, about 0.01 mg/kg/day to about 0.1 mg/kg/day, about 0.01 mg/kg/day to about 0.05 mg/kg/day, about 1 mg/kg/day to about 1,000 mg/kg/day, about 1 mg/kg/day to about 500 mg/kg/day, about 1 mg/kg/day to about 250 mg/kg/day, about 1 mg/kg/day to about 100 mg/kg/day, about 1 mg/kg/day to about 50 mg/kg/day, about 5 mg/kg/day to about 50 mg/kg/day, about 5 mg/kg/day to about 10 mg/kg/day, about 5 mg/kg/day to about 20 mg/kg/day, about 10 mg/kg/day to about 50 mg/kg/day, about 10 mg/kg/day to about 20 mg/kg/day, about 250 mg/kg/day to about 2000 mg/kg/day, about 10 mg/kg/day to about 800 mg/kg/day, about 50 mg/kg/day to about 400 mg/kg/day, about 100 mg/kg/day to about 300 mg/kg/day, or about 150 mg/kg/day to about 200 mg/kg/day. In some embodiments, a compound is administered in an amount of about 1 mg/kg/day, about 2 mg/kg/day, about 5 mg/kg/day, about 10 mg/kg/day, about 20 mg/kg/day, about 50 mg/kg/day, about 100 mg/kg/day, about 150 mg/kg/day, about 200 mg/kg/day, about 250 mg/kg/day, about 300 mg/kg/day, about 350 mg/kg/day, about 400 mg/kg/day, about 450 mg/kg/day, about 500 mg/kg/day, about 550 mg/kg/day, about 600 mg/kg/day, about 650 mg/kg/day, about 700 mg/kg/day, about 750 mg/kg/day, about 800 mg/kg/day, about 850 mg/kg/day, about 900 mg/kg/day, about 950 mg/kg/day or about 1,000 mg/kg/day of subject body mass per day.

In some embodiments, a compound of the disclosure is administered in an amount sufficient to achieve a maximum plasma concentration in a subject (e.g., at steady state) of about 1 ng/ml to about 5,000 ng/ml, for example about 50 ng/ml to about 5,000 ng/ml, about 100 ng/ml to about 5,000 ng/ml, about 200 ng/ml to about 5,000 ng/ml, about 300 ng/ml to about 5,000 ng/ml, about 400 ng/ml to about 5,000 ng/ml, about 500 ng/ml to about 5,000 ng/ml, about 50 ng/ml to about 500 ng/ml, about 100 ng/ml to about 500 ng/ml, about 150 ng/ml to about 500 ng/ml, about 200 ng/ml to about 500 ng/ml, or about 250 ng/ml to about 500 ng/ml.

Methods of Preparation

Pharmaceutical compositions described herein can be manufactured by suitable pharmacological techniques. Suitable pharmacological techniques include, e.g., one or a combination of methods such as (1) wet granulation; (2) dry granulation; (3) dry mixing; (4) direct compression; (5) milling; (6) roller compaction; or (7) fusion. Other methods include, e.g., spray drying, pan coating, melt granulation, granulation, fluidized bed spray drying or coating (e.g., wurster coating), tangential coating, top spraying, tableting, and extruding.

In some embodiments, a tablet disclosed herein is prepared by a wet granulation process. In wet granulation, some or all of the active ingredient(s) and excipients in powder form are blended and then further mixed in the presence of a liquid, for example water, that causes the powders to clump into granules. The granulate dried and then screened and/or milled to the desired particle size. The granulate is then tableted, or other excipients can be added prior to tableting, such as a glidant and/or a lubricant.

In some embodiments, an active ingredient is dissolved with one or more pharmaceutically-acceptable excipients, and the resulting mixture is granulated in the presence of a suitable solvent, for example water. A wet granulate is obtained which can be dried and optionally sifted to obtain a dry granulate. The dry granulate can optionally be mixed with one or more additional pharmaceutically-acceptable excipients, optionally sifted, and compressed into tablets. In some embodiments, a tablet disclosed herein is prepared by a dry granulation process.

In some embodiments, a dry granulation process is a slugging process. Slugging is a dry granulation method in which an active ingredient, optionally in combination with one or more excipients, is first compressed to form a slug and is then milled to form particulates suitable for further processing. For example, a blended composition of the active ingredient(s) and pharmaceutically-acceptable excipients may be compacted into a slug or a sheet and then ground into compacted granules. The compacted granules may subsequently be compressed into a tablet.

In some embodiments, granulation of an active ingredient can be accomplished by a dry granulation method.

In other embodiments, a blended composition can be compressed directly into a compacted dosage form using direct compression techniques. Direct compression produces a more uniform tablet without granules.

In some embodiments, a granulation method comprises a roller compaction method, in which powder size enlargement is accomplished by feeding an active ingredient, optionally in combination with one or more wet or dry excipients, through a roller apparatus, followed by drying (if necessary), milling, and sizing the compacted mixture to form granules having a desired particle size.

In some embodiments, a capsule described herein can comprise any of the aforementioned blends and granulates described with reference to tableting.

EXAMPLES

Example 1: Determination of proportion of heart failure (HF) patients having high burden of premature ventricular contractions/complexes (PVCs), and evaluating the effect of PVCs on cardiac outcomes and death

Introduction

While PVCs are often considered benign, recent evidence suggests that PVCs relate to inefficiency of both the contraction preceding the PVC as well as the PVC itself. Therefore, even a moderate burden of PVCs may be associated with loss of contractile efficiency and an increased risk of cardiac events. It is unclear what proportion of well-treated stable heart failure (HF) patients have a moderate to high burden of PVCs, despite their treatment regimen.

The aim of this study was to estimate the proportion of HF patients that have more than 5% of all heart beats being a PVCs. and to determine if this higher number is related to more cardiac events and/or worse cardiac outcomes, including death.

Methods

Electronic medical records of 662 heart failure patients (59% male) with either an ejection fraction < 40% or N-temiinal pro b-type natriuretic peptide (NTproBNP) ≥600 pg/ml, who received Holter monitoring, were analyzed. The patients were followed for various time periods (e.g., between 1 year and 10 years, but shorter or longer durations are also contemplated). The median baseline age of the patients was 61 years (IQR - [46.00. 72.00]). PVC burden, defined as the percent of all heart beats per a defined time period, e.g., in a minute (60 seconds) or in a day (24 hours), was determined from electrocardiograms on a Holter monitor. During the evaluation, a total of 55 events occurred in 8.3% of the patients. These events included malignant ventricular arrhythmias, cardiac arrest, or death.

Results

The percentage of cardiac events in heart failure (HF) patients with the indicated percent burden of PVCs is summarized in Table 1.

Table 1: Cardiac Events in HF Patients with PVCs

The data shows that approximately 8% of HF patients have a high percentage of PVCs (i.e. defined as >5% of all heartbeats being a PVC). The higher number of PVCs was correlated with an increased number of cardiac events. Use of beta-blockers (standard of care) does not relate to the proportion of PVCs or to the outcome. Thus, the data show that PVCs are not uncommon in stable well-treated heart failure patients and relate to poor outcomes, despite medical therapy with standard of care.

The study further analyzed electronic medical records from 676 adult patients (60% male) with either an ejection fraction < 40% or NTproBNP more than 600 pg/ml who received Holter monitoring. The patients were followed for various time periods (c.g., between 1 year and 10 years, but shorter or longer durations are also contemplated). The median baseline age of the patients was 62 years. PVC burden was measured as described above.

During the study, significantly more patients died in the group with more than 5% PVCs (p < 0.05). The results are shown in Table 2.

Table 2

The data shows that approximately 8.4% of HF patients have a significant burden of PVCs (i.e. >5% of all heartbeats), despite adequate use of beta-blocker therapy. This proportion of PVCs was associated with an increased risk of death over one year. This suggests that in heart failure with reduced ejection fraction (HFrEF) patients. PVCs burden of more than 5% of heartbeats may be associated with worse outcomes.

Example 2 - Treatment of Heart Failure Patients Having Elevated Premature Ventricular Contractions with Ryanodine Receptor calcium channel modulators.

Introduction

In heart failure, Ca ²⁺ concentration in the sarcoplasmic reticulum (SR) may be abnormally regulated. Diastolic leak of Ca ²⁺ from the SR through modified leaky RyR2 Ca ²⁺ release channels can cause delayed after depolarizations (DADs). When the amplitude of a DAD is above a certain threshold (termed a suprathrcshold DAD), it can trigger an action potential (AP) called triggered activity (TA), which can lead to a PVC. Ryanodine receptor channel modulators can preferentially bind to leaky RyR2 channels and induce a conformation change that can shift the open probability of the RyR2 channel towards a closed (resting) state, repairing the channel leak, thereby restoring normal RyR2 function. DADs are distinguished mechanistically from early after depolarizations (EADs), which often occur during bradycardia episodes, due to the reduction of repolarization reserves.

Study Design

In this study, a subset of HF patients are treated with a therapeutically effective amount of the disclosed Ryanodine Receptor calcium channel modulators (including, compound 1). An exemplary formulation comprising Compound 1 is provided in Example 3.

A cohort of HF patients are screened to identify a subset of HF patients having (i) late coupling of the PVCs (i.e., when a PVC initiates after end of a T-wave of a preceding heartbeat), (ii) more than 5% of all beats are PVCs; and (iii) a heart rate greater than 60 beats per minute (bpm), which reduces the likelihood of EADs. The HF cohort is characterized by the following clinical criteria: (i) ICD code for heart failure; or (ii) LVEF < 40%; or (iii) NTproBNP > 600 pg/mL.

The subset of HF patients matching the criteria set forth above for testing with a Ryanodine Receptor calcium channel modulator (e.g., compound 1) are divided into two groups, a control (placebo) and a treatment arm. Subjects are treated with either Compound 1 or placebo for at least 28 days.

Cardiac function is assessed by, for example, ejection fraction, end diastolic volumes, end systolic volumes, cardiac output, N-terminal pro b-type natriuretic peptide (NTproBNP) levels and Holter for measuring PVCs, as well as monitoring patients for all other cardiac events, e.g., ventricular arrhythmias, cardiac arrest, death, asystole, ischemic EKG changes, myocardial infarction. EV dilatation or mitral regurgitation.

In some embodiments, treatment with a Ryanodine Receptor calcium channel modulator (including Compound 1) in the subset of HF patients noted above (i) reduces PVCs below 6-8% of total heart beats, (ii) improves systolic function, i.e., cardiac mechanics, and (iii) reduces the number and/or severity of cardiac events.

In some embodiments, treatment with a Ryanodine Receptor calcium channel modulator (including Compound 1) in the subset of HF patients noted above (i) reduces PVCs below 5% of total heart beats; (ii) improves systolic function, i.e., cardiac mechanics, and (iii) reduces the number and/or severity of cardiac events.

Example 3: Gastro-Resistant Tablet

A gastro-resistant tablet comprising 20 mg 4-[(7-methoxy-2,3-dihydro-1,4- benzothiazepin-4(5H)yl)methyl]benzoic acid hemi-fumarate (Compound 1) (based on the mass of 4-[(7-methoxy-2,3-dihydro-1,4-benzothiazepin-4(5H)yl)methyl] benzoic acid) is provided in Table 3.

Table 3: Gastro-Resistant Tablet

Preparation Method: Compound 1 was mixed with mannitol, cellulose microcrystalline, and maltodextrin. The mixture was granulated via a standard wet granulation process. The obtained wet granulate was dried and sifted. Then, the dry granulate was mixed with croscarmellose, magnesium stearate, silica colloidal anhydrous, and sodium stearyl fumarate. The lubricated granulate was sifted and compressed into tablets.

Subsequently, the core tablets were coated with sub-coating (colourless Sepifilm LP 010). After drying, the enteric coating was applied (AQOAT suspension AS-MF) to obtain enteric-coated tablets.

Example 4: Treatment of Cardiomyocytes with Compound (1) Reduces Calcium Sparks After Myocardial Infarction

Myocardial infarction was induced in anesthetized adult rats by total ligation of left anterior descending (LAD) coronary artery. This permanent ligature led to infarct of the left ventricle with structural and electrical remodeling of the myocardium. Two groups (13 animals per group) were compared: Sham operated (SHAM, placebo surgery) and post-myocardial infarction (PMI) rats.

Two to three months after the infarct, rats were sacrificed under anesthesia and cardiomyocytes were isolated. For each rat (SHAM or PMI) 20 cells were assessed, receiving the following treatments for at least 2 hours (i) for SHAM rats, 10 cells were treated with 10 μM Compound (1) (SHAM treated group) and 10 cells received the vehicle water (SHAM untreated group); or (ii) for PMI rats, 10 cells were treated with 10 μM Compound (1) (PMI treated group) and 10 cells received the vehicle water (PMI untreated group).

During the last 30 min, the cardiomyocytes were loaded with 5μM Fluo-4AM at 37°C, a fluorescent calcium- sensitive indicator. Calcium sparks and calcium waves were detected using a laser scanning confocal microscope (excitation at 488 nm and measurement at 505-550 nm). Scan line technology was used to detect calcium sparks happening along a line running through the cardiomyocytc. Two-dimensional images integrating calcium signal over time were produced.

The results show that calcium sparks are induced by the injury and subsequent heart failure in the rat cardiomyocytes, and the increase was ablated by treatment with Compound (1) (FIG. 1). The mean percentages of presence of calcium sparks were 45.3% in the PMI control group versus 17.7% in the SHAM control group (FIG. 1). The probability of having calcium sparks was significantly higher in the PMI control group than in the SHAM control group (p < 0.001). These results confirmed the RyR engagement (more leaky channels) in the PMI rat cardiomyocytes in the absence of external calcium.

The mean percentages of presence of calcium sparks were 28.5% in the PMI treated group versus 45.3% in the PMI control group (FIG. 1). In PMI cardiomyocytes, treatment with Compound (1) significantly decreased (p < 0.001) the probability of having calcium sparks as compared with untreated PMI cardiomyocytes.

Example 5: Effect of Compound (1) on Arrythmia Induced by Isoprenaline and FK506 in isolated Rat Cardiomyocytes

Isoprenaline is a beta-adrenergic agonist that induces PKA-dependent phosphorylation of RyR2, while FK506 is a macrolide that binds, among different proteins, Calstabin2 and dissociates it from RyR2. The two agents alter the gating of RyR2 toward an unstable state of increased opening, and thus induce arrhythmic events as shown by calcium sparks. The effect of the Compound (1) on arrhythmia was examined by image analysis of Ca ²⁺ signals using a fluorescent Ca ²⁺ probe.

The contractile properties of isolated adult ventricular cardiomyocytes as well as their intracellular Ca ²⁺ transient shapes were analyzed by fluorescence video image analysis, using the lonOptix system. This system combines video-optical recordings of sarcomere movements with fluorescent dye-based monitoring of the intracellular Ca ²⁺ signal in electrically stimulated cardiomyocytes. Experiments were performed on adult rat cardiomyocytes, freshly isolated by collagenase digestion of the myocardium via retrograde heart perfusion. Cardiomyocytes were seeded in lonOptix chambers in the presence of Compound (1) (1 μM and 10 μM) or vehicle (water) and were incubated at least 2 hours. Then Fura-2AM, a fluorescent Ca ²⁺ -scnsitivc probe used to record intracellular Ca ²⁺ concentration, was loaded for 30 min. Cells were then washed, and after 10 min transferred to the lonOptix system.

Cardiomyocytes were electrically paced at 1 Hz and recording of unstimulated, spontaneous calcium signals including waves and peaks (collectively, arrhythmic events) and sarcomere contraction (in case the calcium signal could not be recorded) was started. Arrhythmic events were induced after 1 minute of recording under basal conditions, by adding isoprenaline + FK506. Calcium signal and sarcomere contraction were recorded for 10 min (including 1 min under basal conditions) to evaluate the effect of Compound (1) in comparison with vehicle (water) on arrhythmic events induced by 10 nM isoprenaline and 10 μM FK506. Starting with pre-treatment and throughout all experiment, cardiomyocytes were constantly exposed, without interruption, to either vehicle or Compound (1) at 1 or 10 μM.

The results show that 10 uM Compound (1) effectively reduced Ca ²⁺ sparks induced by isoprenaline and FK506 exposure (FIG. 2). In cardiomyocytcs of the vehicle group, the median number of calcium signals (i.e., arrhythmic events) increased over time from 3 min, showing that isoprenaline + FK506 effectively induced arrhythmic events. T h e median number of arrhythmic events was 0.5 at the time of 3 min, 27.0 at 8 min, 25.0 at 9 min, and 34.0 at 10 min of recording. Compound (1) at 1 μM showed globally the same number of arrhythmic events than observed with the vehicle (no statistical difference between groups). The median number of arrhythmic events was 0.5 at the time of 3 min, 20.0 at 8 min, 28.5 at 9 min, and 29.5 at 10 min of recording. With higher concentration of Compound (1) (10 μM), there was a treatment-effect in comparison with the vehicle. For example, at 10 μM Compound (1) showed a statistically significant decrease in the number of arrhythmic events induced by isoprenaline + FK506 at the time of 8, 9, and 10 min of recording (p = 0.013, p = 0.032 and p = 0.022 respectively). The median number of arrhythmic events was: (i) at 8 minutes: 1.0 with Compound (1) 10 μM versus 27.0 in the vehicle; (ii) at 9 minutes: 7.0 with Compound (1) 10 μM versus 25.0 in the vehicle; and (iii) at 10 minutes: 8.0 with Compound (1) 10 μM versus 34.0 in the vehicle. NUMBERED EMBODIMENTS

Embodiment 1. A method of treating a subject with a Ryanodine Receptor calcium channel modulator, comprising:

(i) determining if the subject has heart failure characterized by:

(a) a premature ventricular contraction (PVC) burden of at least about 5% of all heartbeats within a time period, wherein the PVC initiates after end of a T-wave of a preceding heartbeat; and

(b) a heart rate preceding the PVC of at least about 60 beats per minute; and,

(ii) administering a therapeutically effective amount of the Ryanodine Receptor calcium channel modulator to the subject.

Embodiment 2. The method of embodiment 1, wherein the time period ranges from about 60 seconds to about 24 hours.

Embodiment 3. The method of embodiment 1 or 2, wherein the time period is 60 seconds.

Embodiment 4. The method of embodiment 1 or 2, wherein the time period is 24 hours.

Embodiment 5. The method of any one of embodiments 1-4, wherein the PVC burden ranges from about 5% of all heartbeats to about 20% of all heartbeats within the time period.

Embodiment 6. The method of any one of embodiments 1-5, wherein the PVC burden is at least about 10% of all heartbeats within the time period.

Embodiment 7. The method of any one of embodiments 1-6, wherein the heart rate preceding the PVC is at least about 70 beats per minute.

Embodiment 8. The method of any one of embodiments 1-7, wherein the subject has an ejection fraction less than about 40%. Embodiment 9. The method of any one of embodiments 1 -8, wherein the heart failure is further characterized by an N-terminal pro-b-type natriuretic peptide test greater than about 1,000 pg/mL.

Embodiment 10. The method of any one of embodiments 1-8, wherein the heart failure is further characterized by an N-terminal pro-b-type natriuretic peptide test greater than about 600 pg/mL.

Embodiment 11. The method of any one of embodiments 1-10, wherein the subject has PVCs having at least two morphologies.

Embodiment 12. The method of embodiment 11, wherein the PVCs are multi-focal.

Embodiment 13. The method of embodiment 11, wherein the PVCs are not unifocal.

Embodiment 13a. The method of embodiment 13, wherein the PVCs originate from a single foci.

Embodiment 13b. The method of embodiment 13a, wherein the PVCs have at least two distinct morphologies.

Embodiment 13c. The method of embodiment 13, wherein the PVCs originate from different (multiple) foci.

Embodiment 13d. The method of embodiment 13c, wherein the PVCs have at least two distinct morphologies.

Embodiment 14. The method of any one of embodiments 1-13, 13a - 13d, wherein the treatment of the subject decreases the number of PVCs.

Embodiment 15. The method of embodiment 14, wherein the PVCs are decreased by greater than about fifty percent (50%). Embodiment 16.The method of any one of embodiments 1 -15, wherein the treatment of the subject improves left ventricular function.

Embodiment 17. The method of any one of embodiments 1-16, wherein the treatment of the subject decreases the level of N-terminal pro-b-type natriuretic peptide.

Embodiment 18. The method of any one of embodiments 1-17, wherein the treatment decreases at least one adverse cardiac event in the subject.

Embodiment 19. The method of embodiment 18, wherein the adverse cardiac event is ventricular arrhythmia.

Embodiment 20. The method of embodiment 18, wherein the adverse cardiac event results in death.

Embodiment 21. The method of embodiment 20, wherein the treatment decreases the likelihood of death in the subject.

Embodiment 22. The method of embodiment 18, wherein the adverse cardiac event is cardiac arrest.

Embodiment 23. The method of any one of embodiments 1-22, wherein the PVC is triggered by a delayed after depolarization (DAD), wherein the DAD results from a leak of Ca ⁺² from RyR2.

Embodiment 24. The method of embodiments 23, wherein the leak is a diastolic Ca ⁺² leak.

Embodiment 25. The method of embodiments 23 or 24, wherein the RyR2 is a post- translationally modified RyR2.

Embodiment 26. The method of embodiment 25, wherein the RyR2 post-translational modification is at least one of nitrosylation, oxidation or phosphorylation. Embodiment 27. The method of any one of embodiments 1-26, wherein the calcium channel modulator is represented by the following structure: wherein R is COOH, or a pharmaceutically-acceptable salt thereof.

Embodiment 28. The method according to embodiment 27, wherein the calcium channel modulator is in the form of a salt with a pharmaceutically-acceptable acid or base.

Embodiment 29. The method according to embodiment 28, wherein the salt is selected from the group consisting of hemifumarate, sodium, potassium, magnesium, hydrochloride and hydrobromide, preferably wherein the salt is the sodium or the hemifumarate salt.

Embodiment 30. The method according to embodiment 28 or 29, wherein the salt is a hemifumarate salt.

Embodiment 31. The method of any one of embodiments 27-30, wherein the calcium channel modulator is represented by the following structure: or a pharmaceutically-acceptable salt thereof.

Embodiment 32. The method of any one of embodiments 1-26, wherein the calcium channel modulator is represented by the following structure: or a pharmaceutically-acceptable salt thereof, wherein each R ^1a , R ^1b , R ^1c , and R ^1d is independently alkyl, haloalkyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heteroaryl, heterocyclyl, -CN, -NO ₂ , -N ₃ . -NR ³ R ⁴ , -OR ⁵ , -SO ₃ H, - SO ₂ R ⁶ , -OSO ₂ R ⁶ , -S(O)R ⁶ , or -SR ⁷ , each of which is independently substituted or unsubstituted, or hydrogen or halogen,

R ² is alkyl, haloalkyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heteroaryl, heterocyclyl, -C(O)NR ³ R ⁴ , -C(O)C(O)NR ³ R ⁴ , -C(O)R ⁸ , -C(O)OR ⁸ , or -C(O)C(O)OR ⁸ , each of which is independently substituted or unsubstituted, each R ³ and R ⁴ is independently alkyl, haloalkyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heteroaryl, or heterocyclyl, each of which is independently substituted or unsubstituted, or hydrogen or halogen; or R ³ and R ⁴ together with the nitrogen atom to which R ³ and R ⁴ are attached form a heterocyclic or heteroaromatic ring, which is unsubstituted or substituted, and each R ⁵ , R ⁶ , R ⁷ , and R ⁸ is independently alkyl, haloalkyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heteroaryl, or heterocyclyl, each of which is independently substituted or unsubstituted, or hydrogen or halogen.

Embodiment 33. The method of any one of embodiments 1-26, wherein the calcium channel modulator is represented by the following structure:

wherein, n is 0, 1, or 2; q is 0, 1, 2, 3, or 4; each R is independently acyl, -O-acyl, alkyl, alkoxyl, alkylamino, alkylarylamino, alkylthio, cycloalkyl, alkylaryl, aryl, heteroaryl, heterocyclyl, heterocyclylalkyl, alkenyl, alkynyl, arylthio, arylamino, heteroarylthio, or heteroarylamino, each of which is independently substituted or unsubstituted; or halogen, -OH, -NH ₂ , -NO ₂ , -CN, -CF ₃ , - OCF ₃ , -N ₃ , -SO ₃ H, -S(=O) ₂ alkyl, -S(=O)alkyl, or -OS(=O) ₂ CF ₃ ;

R ¹ is alkyl, alkenyl, aryl, alkylaryl, cycloalkyl, heteroaryl, or heterocyclyl, each of which is independently substituted or unsubstituted; or H;

R ² is alkyl, aryl, alkylaryl, heteroaryl, cycloalkyl, cycloalkylalkyl, or heterocyclyl, each of which is independently substituted or unsubstituted; or H, -C(=O)R ⁵ , -C(=S)R ⁶ , - SO ₂ R ⁷ , -P(=O)R ⁸ R ⁹ , or -(CH ₂ ) _m -R ¹⁰ ;

R ³ is acyl, -O-acyl, alkyl, alkenyl, aryl, alkylaryl, cycloalkyl, heteroaryl, or heterocyclyl, each of which is independently substituted or substituted; or H, -CO ₂ Y, or -C(=O)NHY; Y is alkyl, aryl, alkylaryl, cycloalkyl, heteroaryl, or heterocyclyl, each of which is independently substituted or unsubstituted; or H;

R ⁴ is alkyl, alkenyl, aryl, alkylaryl, cycloalkyl, heteroaryl, or heterocyclyl, each of which is independently substituted or unsubstituted; or H; each R ⁵ is acyl, alkyl, alkenyl, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or -NR ¹⁵ R ¹⁶ . -(CH ₂ ) _t NR ¹⁵ R ¹⁶ , -NHNR ¹⁵ R ¹⁶ . -NHOH. -OR ¹⁵ . - C(=O)NHNR ¹⁵ R ¹⁶ , -CO ₂ R ¹⁵ , -C(=O)NR ¹⁵ R ¹⁶ , or -CH ₂ X; each R ⁶ is acyl, alkenyl, alkyl, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or -OR ¹⁵ , -NHNR ¹⁵ R ¹⁶ , -NHOH, -NR ¹⁵ R ¹⁶ , or -CH ₂ X; each R ⁷ is alkyl, alkenyl, alkynyl, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or -OR ¹⁵ . -NR ¹⁵ R ¹⁶ , -NHNR ¹⁵ R ¹⁶ , -NHOH, or -CH ₂ X; each R ⁸ and R ⁹ are each independently acyl, alkenyl, alkoxyl, alkyl, alkylamino, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or OH; each R ¹⁰ is -NR ¹⁵ R ¹⁶ , OH, -SO ₂ R ¹¹ , -NHSO ₂ R ¹¹ , -C(=O)(R ¹² ), -NHC=O(R ¹² ), - OC=O(R ¹² ), or -P(=O)R ¹³ R ¹⁴ ; each R ¹¹ , R ¹² , R ¹³ , and R ¹⁴ is independently acyl, alkenyl, alkoxyl, alkyl, alkylamino, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or H, OH, NH ₂ , -NHNH ₂ , or -NHOH; each X is independently halogen, -CN, -CO ₂ R ¹⁵ , -C(=O)NR ¹⁵ R ¹⁶ , -NR ¹⁵ R ¹⁶ , -OR ¹⁵ , - SO ₂ R ⁷ , or -P(=O)R ⁸ R ⁹ ; and each R ¹⁵ and R ¹⁶ is independently acyl, alkenyl, alkoxyl, OH, NH ₂ , alkyl, alkylamino, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted, or H; or R ¹⁵ and R ¹⁶ together with the N to which R ¹⁵ and R ¹⁶ are bonded form a heterocycle that is substituted or unsubstituted; t is 1, 2, 3, 4, 5, or 6; m is 1, 2, 3, or 4; or a pharmaceutically-acceptable salt thereof.

Embodiment 34. A method of identifying a subject suitable for treatment with a Ryanodine Receptor calcium channel modulator, comprising:

(i) determining if the subject has heart failure characterized by:

(a) a premature ventricular contraction (PVC) burden of at least about 5% of all heartbeats within time period, wherein the PVC initiates after end of a T-wave of a preceding heartbeat; and

(b) a heart rate preceding the PVC of at least 60 beats per minute. Embodiment 35. The method of embodiment 34, wherein the time period ranges from about 60 seconds to about 24 hours.

Embodiment 36. The method of embodiment 34 or 35, wherein the time period is 60 seconds.

Embodiment 37. The method of embodiment 34 or 35, wherein the time period is 24 hours.

Embodiment 38. The method of any one of embodiments 34-37, wherein the PVC burden ranges from about 5% of all heartbeats to about 20% of all heartbeats within the time period.

Embodiment 39. The method of any one of embodiments 34-38, wherein the PVC burden is at least about 10% of all heartbeats within the time period.

Embodiment 40. The method of any one of embodiments 34-39, wherein the heart rate preceding the PVC is at least about 70 beats per minute.

Embodiment 41. The method of any one of embodiments 34-40, wherein the subject has an ejection fraction less than about 40%.

Embodiment 42. The method of any one of embodiments 34-41, wherein the heart failure is further characterized by an N-terminal pro-b-type natriuretic peptide test greater than about 1,000 pg/mL.

Embodiment 43. The method of any one of embodiments 34-41, wherein the heart failure is further characterized by an N-terminal pro-b-type natriuretic peptide test greater than about 600 pg/mL.

Embodiment 44. The method of any one of embodiments 34-43, wherein the subject has PVCs having at least two morphologies.

Embodiment 45. The method of embodiment 44, wherein the PVCs are multi-focal. Embodiment 46. The method of embodiment 44, wherein the PVCs arc not unifocal.

Embodiment 46a. The method of embodiment 46, wherein the PVCs originate from a single foci.

Embodiment 46b. The method of embodiment 46a, wherein the PVCs have at least two distinct morphologies.

Embodiment 46c. The method of embodiment 46, wherein the PVCs originate from different (multiple) foci.

Embodiment 46d. The method of embodiment 46c, wherein the PVCs have at least two distinct morphologies.

Embodiment 47. The method of any one of embodiments 34-46, or 46a -46d, wherein the treatment of the subject decreases the number of PVCs.

Embodiment 48. The method of embodiment 47, wherein the PVCs are decreased by greater than about fifty percent (50%).

Embodiment 49. The method of any one of embodiments 34-48, wherein the treatment of the subject improves left ventricular function.

Embodiment 50. The method of any one of embodiments 34-49, wherein the treatment of the subject decreases the level of N-terminal pro-b-type natriuretic peptide.

Embodiment 51. The method of any one of embodiments 34-50, wherein the treatment of the subject decreases at least one adverse cardiac event in the subject.

Embodiment 52. The method of embodiment 51, wherein the adverse cardiac event is ventricular arrhythmia. Embodiment 53. The method of embodiment 51, wherein the adverse cardiac event results in death.

Embodiment 54. The method of embodiment 53, wherein the treatment decreases the likelihood of death in the subject.

Embodiment 55. The method of embodiment 51, wherein the adverse cardiac event is cardiac arrest.

Embodiment 56. The method of any one of embodiments 34-55, wherein the PVC is triggered by a delayed after depolarization (DAD), wherein the DAD results from a leak of Ca ⁺² from RyR2.

Embodiment 57. The method of claim 56, wherein the leak is a diastolic Ca ⁺² leak.

Embodiment 58. The method of claim 56, wherein the RyR2 is a post-translationally modified RyR2.

Embodiment 59. The method of claim 58, wherein the RyR2 post-translational modification is at least one of nitro sylation, oxidation or phosphorylation.

Embodiment 60. The method of any one of embodiments 34-59, further comprising the step of administering a therapeutically effective amount of the Ryanodine Receptor calcium channel modulator to the subject.

Embodiment 61. The method of embodiment 60, wherein the calcium channel modulator is represented by the following structure: wherein R is COOH, or a pharmaceutically-acceptable salt thereof.

Embodiment 62. The method according to embodiment 61, wherein the calcium channel modulator is in the form of a salt with a pharmaceutically-acceptable acid or base.

Embodiment 63. The method according to embodiment 62, wherein the salt is selected from the group consisting of hemifumarate, sodium, potassium, magnesium, hydrochloride and hydrobromide, preferably wherein the salt is the sodium or the hemifumarate salt.

Embodiment 64. The method according to embodiment 62 or 63. wherein the salt is a hemifumarate salt.

Embodiment 65. The method of any one of embodiments 61-64, wherein the calcium channel modulator is represented by the following structure: or a pharmaceutically-acceptable wait thereof.

Embodiment 66. The method of embodiment 60, wherein the calcium channel modulator is represented by the following structure:

or a pharmaceutically-acceptable salt thereof, wherein each R ^1a , R ^1b , R ^1c , and R ^1d is independently alkyl, haloalkyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heteroaryl, heterocyclyl, -CN, -NO ₂ , -N ₃ , -NR ³ R ⁴ , -OR ⁵ , -SO ₃ H, - SO ₂ R ⁶ , -OSO ₂ R ⁶ , -S(O)R ⁶ , or -SR ⁷ , each of which is independently substituted or unsubstituted, or hydrogen or halogen,

R ² is alkyl, haloalkyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heteroaryl, heterocyclyl, -C(O)NR ³ R ⁴ , -C(O)C(O)NR ³ R ⁴ , -C(O)R ⁸ , -C(O)OR ⁸ , or -C(O)C(O)OR ⁸ , each of which is independently substituted or unsubstituted, each R ³ and R ⁴ is independently alkyl, haloalkyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heteroaryl, or heterocyclyl, each of which is independently substituted or unsubstituted, or hydrogen or halogen; or R ³ and R ⁴ together with the nitrogen atom to which R ³ and R ⁴ are attached form a heterocyclic or heteroaromatic ring, which is unsubstituted or substituted, and\ each R ⁵ , R ⁶ , R ⁷ , and R ⁸ is independently alkyl, haloalkyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, aryl, benzyl, heteroaryl, or heterocyclyl, each of which is independently substituted or unsubstituted, or hydrogen or halogen.

Embodiment 67. The method of embodiment 60, wherein the calcium channel modulator is represented by the following structure: wherein, n is 0, 1, or 2; q is 0, 1, 2, 3, or 4; each R is independently acyl, -O-acyl, alkyl, alkoxyl, alkylamino, alkylarylamino, alkylthio, cycloalkyl, alkylaryl, aryl, heteroaryl, heterocyclyl, heterocyclylalkyl, alkenyl, alkynyl, arylthio, arylamino, heteroarylthio, or heteroarylamino, each of which is independently substituted or unsubstituted; or halogen, -OH, -NH ₂ , -NO ₂ , -CN, -CF ₃ , - OCF ₃ , -N ₃ , -SO ₃ H, -S(=O) ₂ alkyl, -S(=O)alkyl, or -OS(=O) ₂ CF ₃ ;

R ¹ is alkyl, alkenyl, aryl, alkylaryl, cycloalkyl, heteroaryl, or heterocyclyl, each of which is independently substituted or unsubstituted; or H;

R ² is alkyl, aryl, alkylaryl, heteroaryl, cycloalkyl, cycloalkylalkyl, or heterocyclyl, each of which is independently substituted or unsubstituted; or H, -C(=O)R ⁵ , -C(=S)R ⁶ , - SO ₂ R ⁷ , -P(=O)R ⁸ R ⁹ , or -(CH ₂ ) _m -R ¹⁰ ;

R ³ is acyl, -O-acyl, alkyl, alkenyl, aryl, alkylaryl, cycloalkyl, heteroaryl, or heterocyclyl, each of which is independently substituted or substituted; or H, -CO ₂ Y, or -C(=O)NHY; Y is alkyl, aryl, alkylaryl, cycloalkyl, heteroaryl, or heterocyclyl, each of which is independently substituted or unsubstituted; or H;

R ⁴ is alkyl, alkenyl, aryl, alkylaryl, cycloalkyl, heteroaryl, or heterocyclyl, each of which is independently substituted or unsubstituted; or H; each R ⁵ is acyl, alkyl, alkenyl, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or -NR ¹⁵ R ¹⁶ , -(CH ₂ ) _t NR ¹⁵ R ¹⁶ , -NHNR ¹⁵ R ¹⁶ , -NHOH, -OR ¹⁵ , - C(=O)NHNR ¹⁵ R ¹⁶ , -CO ₂ R ¹⁵ , -C(=O)NR ¹⁵ R ¹⁶ , or -CH ₂ X; each R ⁶ is acyl, alkenyl, alkyl, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or -OR ¹⁵ , -NHNR ¹⁵ R ¹⁶ , -NHOH, -NR ¹⁵ R ¹⁶ , or -CH ₂ X; each R ⁷ is alkyl, alkenyl, alkynyl, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or -OR ¹⁵ . -NR ¹⁵ R ¹⁶ , -NHNR ¹⁵ R ¹⁶ , -NHOH, or -CH ₂ X; each R ⁸ and R ⁹ are each independently acyl, alkenyl, alkoxyl, alkyl, alkylamino, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or OH; each R ¹⁰ is -NR ¹⁵ R ¹⁶ , OH, -SO ₂ R ¹¹ , -NHSO ₂ R ¹¹ , -C(=O)(R ¹² ), -NHC=O(R ¹² ), - OC=O(R ¹² ), or -P(=O)R ¹³ R ¹⁴ ; each R ¹¹ , R ¹² , R ¹³ , and R ¹⁴ is independently acyl, alkenyl, alkoxyl, alkyl, alkylamino, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted; or H, OH, NH ₂ , -NHNH ₂ , or -NHOH; each X is independently halogen, -CN, -CO ₂ R ¹⁵ , -C(=O)NR ¹⁵ R ¹⁶ , -NR ¹⁵ R ¹⁶ , -OR ¹⁵ , - SO ₂ R ⁷ , or -P(=O)R ⁸ R ⁹ ; and each R ¹⁵ and R ¹⁶ is independently acyl, alkenyl, alkoxyl, OH, NH ₂ , alkyl, alkylamino, aryl, alkylaryl, cycloalkyl, cycloalkylalkyl, heteroaryl, heterocyclyl, or heterocyclylalkyl, each of which is independently substituted or unsubstituted, or H; or R ¹⁵ and R ¹⁶ together with the N to which R ¹⁵ and R ¹⁶ are bonded form a heterocycle that is substituted or unsubstituted; t is 1, 2, 3, 4, 5, or 6; m is 1, 2, 3, or 4; or a pharmaceutically-acceptable salt thereof.