MYK-461 (also known as Mavacamten) is a small-molecule modulator of cardiac myosin that targets the underlying sarcomere hypercontractility of hypertrophic cardiomyopathy, one of the most prevalent heritable cardiovascular disorders. Studies on isolated cells and muscle fibers, as well as intact animals, have shown that MYK-461 inhibits sarcomere force production, thereby reducing cardiac contractility. In Phase II clinical trials MYK-461 reduces left ventricular outflow tract obstruction and improve exercise capacity and symptoms in patients with obstructive hypertrophic cardiomyopathy. Phase III clinical trials are currently ongoing.

Ganaxolone (3alpha-hydroxy-3beta-methyl-5alpha-pregnan-20-one) (GNX) is the 3beta-methylated synthetic analog of allopregnanolone; it belongs to a class of compounds referred to as neurosteroids. GNX is an allosteric modulator of GABA(A) receptors acting through binding sites which are distinct from the benzodiazepine binding site. It has activity in a broad range of animal models of epilepsy. GNX has been shown to be well tolerated in adults and children. In early phase II studies, GNX has been shown to have activity in adult patients with partial-onset seizures and epileptic children with history of infantile spasms. It is currently undergoing further development in infants with newly diagnosed infantile spasms, in women with catamenial epilepsy, and in adults with refractory partial-onset seizures. Ganaxolone is a CNS-selective GABAA modulator being developed in three different dose forms (IV, capsule, and liquid) intended to maximize therapeutic reach to adult and pediatric patients in both acute and chronic care settings.Ganaxolone is a synthetic analog of endogenous allopregnanolone, which has been shown to be an effective anticonvulsant by restoring electrical balance to the seizing brain. While allopregnanolone’s anticonvulsant and anti-anxiety activities are well documented, allopregnanolone has the potential to convert back to its metabolic precursor progesterone, which could lead to hormonal side effects. Ganaxolone has been designed with an added methyl group that prevents back conversion to an active steroid which unlocks ganaxolone’s potential for chronic use. In preclinical studies, ganaxolone exhibited potency and efficacy comparable to allopregnanolone. Both ganaxolone and allopregnanolone bind to GABAA at the synaptic and extrasynaptic binding sites. Activity with extrasynaptic GABAA receptors are of particular importance for treating patients who developed tolerance to benzodiazepines and barbiturates. Ganaxolone binds to the GABAA receptors, which opens the pore to allow chloride ions to move into the postsynaptic neuron, leading to the inhibition of neurotransmission.

TAK-536 (generic name: azilsartan) is an angiotensin II type 1 receptor blocker, discovered by Takeda and its mechanism of action is to lower blood pressure by inhibiting action of a vasopressor hormone Angiotensin II. Angiotensin II type 1 receptor antagonists have become an important drug class in the treatment of hypertension and heart failure. TAK-536 is in phase III clinical trial for treatment hypertension. This drug also known as active metabolite of the prodrug azilsartan medoxomil (also known as azilsartan kamedoxomil), but in some countries azilsartan rather than its prodrug is used for oral treatment.

Olmesartan medoxomil, a prodrug, is hydrolyzed to olmesartan during absorption from the gastrointestinal tract. Olmesartan is a selective AT1 subtype angiotensin II receptor antagonist. Olmesartan blocks the vasoconstrictor effects of angiotensin II by selectively blocking the binding of angiotensin II to the AT1 receptor in vascular smooth muscle. Oral olmesartan medoxomil 10-40 mg once daily is recommended for the treatment of adult patients with hypertension, this dosage has consistently helped achieve a double-digit reduction both in systolic and diastolic blood pressure, a reduction which is maintained for one year. Extensive clinical evidence from several large well designed trials and the clinical practice setting has confirmed the antihypertensive efficacy and good tolerability profile of oral olmesartan medoxomil, as monotherapy in patients with hypertension. Olmesartan medoxomil has shown no clinically important pharmacokinetic interactions with digoxin, warfarin or antacid (aluminium magnesium hydroxide). Adverse events were infrequent in clinical studies of olmesartan medoxomil and were similar to those attributed to placebo.

Candesartan is classified as an angiotensin II receptor type 1 antagonist. Candesartan is an orally active lipophilic drug and possesses rapid oral absorption. It causes a reduction in blood pressure and is used in the treatment of hypertension. It is also used in the treatment of congestive heart failure and given as prophylaxis to reduce the severity and duration of migraine. Candesartan cilexetil, a prodrug of Candesartan, is available in the market under the trade names Atacand, Amias. Candesartan cilexetil is rapidly converted to candesartan, its active metabolite, during absorption from the gastrointestinal tract. Candesartan confers blood pressure lowering effects by antagonizing the hypertensive effects of angiotensin II via the RAAS (renin–angiotensin–aldosterone system). RAAS is a homeostatic mechanism for regulating hemodynamics, water, and electrolyte balance. During sympathetic stimulation or when renal blood pressure or blood flow is reduced, renin is released from granular cells of the juxtaglomerular apparatus in the kidneys. Renin cleaves circulating angiotensinogen to angiotensin I, which is cleaved by angiotensin converting enzyme (ACE) to angiotensin II. Angiotensin II increases blood pressure by increasing total peripheral resistance, increasing sodium and water reabsorption in the kidneys via aldosterone secretion, and altering the cardiovascular structure. Angiotensin II binds to two receptors: type-1 angiotensin II receptor (AT1) and type-2 angiotensin II receptor (AT2). Candesartan selectively blocks the binding of angiotensin II to AT1 in many tissues including vascular smooth muscle and the adrenal glands. This inhibits the AT1-mediated vasoconstrictive and aldosterone-secreting effects of angiotensin II and results in an overall decrease in blood pressure. Candesartan is greater than 10,000 times more selective for AT1 than AT2.

Telmisartan is an orally active nonpeptide angiotensin II antagonist that acts on the AT1 receptor subtype. It was discovered by Boehringer Ingelheim and launched in 1999 as Micardis. It has the highest affinity for the AT1 receptor among commercially available ARBS and has minimal affinity for the AT2 receptor. New studies suggest that telmisartan may also have PPARγ agonistic properties that could potentially confer beneficial metabolic effects, as PPARγ is a nuclear receptor that regulates specific gene transcription, and whose target genes are involved in the regulation of glucose and lipid metabolism, as well as anti-inflammatory responses. This observation is currently being explored in clinical trials. Angiotensin II is formed from angiotensin I in a reaction catalyzed by angiotensin-converting enzyme (ACE, kininase II). Angiotensin II is the principal pressor agent of the renin-angiotensin system, with effects that include vasoconstriction, stimulation of synthesis and release of aldosterone, cardiac stimulation, and renal reabsorption of sodium. Telmisartan works by blocking the vasoconstrictor and aldosterone secretory effects of angiotensin II. Telmisartan interferes with the binding of angiotensin II to the angiotensin II AT1-receptor by binding reversibly and selectively to the receptors in vascular smooth muscle and the adrenal gland. As angiotensin II is a vasoconstrictor, which also stimulates the synthesis and release of aldosterone, blockage of its effects results in decreases in systemic vascular resistance. Telmisartan does not inhibit the angiotensin converting enzyme, other hormone receptors, or ion channels. Studies also suggest that telmisartan is a partial agonist of PPARγ, which is an established target for antidiabetic drugs. This suggests that telmisartan can improve carbohydrate and lipid metabolism, as well as control insulin resistance without causing the side effects that are associated with full PPARγ activators. Used alone or in combination with other classes of antihypertensives for the treatment of hypertension. Telmisartan is used in the treatment of diabetic nephropathy in hypertensive patients with type 2 diabetes mellitus, as well as the treatment of congestive heart failure (only in patients who cannot tolerate ACE inhibitors).

Irbesartan is an angiotensin receptor blocker (ARB) used mainly for the treatment of hypertension. It was developed by Sanofi Research (now part of Sanofi-Aventis). It is marketed under the trade names Aprovel, Karvea, and Avapro. AVAPRO is an angiotensin II receptor blocker (ARB) indicated for: • Treatment of hypertension, to lower blood pressure. Lowering blood pressure reduces the risk of fatal and nonfatal cardiovascular events, primarily strokes and myocardial infarctions. • Treatment of diabetic nephropathy in hypertensive patients with type 2 diabetes, an elevated serum creatinine, and proteinuria. Irbesartan is a specific competitive antagonist of AT1 receptors with a much greater affinity (more than 8500-fold) for the AT1 receptor than for the AT2 receptor and no agonist activity.

Losartan is a selective, competitive angiotensin II receptor type 1 (AT1) antagonist. Losartant is recommended as one of several preferred agents for the initial management of hypertension. Administration of losartan reduces the risk of stroke in patients with hypertension and left ventricular hypertrophy. Losartan is indicated for the treatment of diabetic nephropathy with an elevated serum creatinine and proteinuria in patients with type 2 diabetes and a history of hypertension.

Naluzotan (PRX-00023), a small molecule, non-azapirone, dual serotonin (5-HT)1A receptor agonist and sigma-1 receptor antagonist, is under development with Proximagen for the treatment of epilepsy. In previous clinical trials, the compound was shown to be safe and well-tolerated in over 400 patients. Epilepsy patients with localisation-related epilepsy have reduced 5-HT1a receptor binding as indicated by positron emission tomography (PET scan). It is thought that by increasing neurotransmitter activity at 5-HT1a receptor sites, seizure incidence and severity may be decreased.