ABT-639 is a T-type calcium (Cav3.2) channel antagonist that was in development with AbbVie for the treatment for pain. ABT-639 is a potent and selective T-type calcium channel blocker. ABT-639 effectively reduces nociceptive and neuropathic pain in rats. ABT-639 produces robust antinociceptive activity in experimental pain models at doses that do not significantly alter psychomotor or hemodynamic function in the rat. ABT-639 blocks recombinant human T-type (Cav3.2) Ca2+ channels in a voltage-dependent fashion (IC50=2 uM) and attenuates low voltage-activated (LVA) currents in rat DRG neurons (IC50=8 uM). ABT-639 was significantly less active at other Ca²⁺ channels (e.g. Ca(v)1.2 and Ca(v)2.2) (IC₅₀ > 30 uM). ABT-639 has high oral bioavailability (%F = 73), low protein binding (88.9%) and a low brain:plasma ratio (0.05:1) in rodents.

Eleclazine (formerly known as GS-6615) is a dihydrobenzoxazepinone selective cardiac late sodium current inhibitor. Gilead Sciences is developing eleclazine as an oral treatment for long QT syndrome, hypertrophic cardiomyopathy, ischaemic heart disease, and Ventricular arrhythmias.

Oleandrin is a toxic cardiac glycoside found in oleander (Nerium oleander L.). Along with neandrin it is primarily responsible for the toxicity of the sap of oleander. Oleandrin has been used for many years in China and Russia for its properties as a cardiac glycoside, for both suicidal and therapeutic purposes as in treatment of cardiac insufficiency. Because of its properties as a cardiac glycoside, oleandrin interferes in some essential processes within the cell, the most important of these being the inhibition of the Na-K ATPase. This protein enables the cell to exchange the cations Na+ and K+ between the intercellular and extracellular spaces by which, for instance, electronic signaling is made possible in nerve cells. Oleandrin binds to specific amino acids in the protein, causing it to lose its function. After depolarization of the cell in which Na+ flows into the cell, the Na+ cannot be transported back into the extracellular membrane, causing the sodium gradient to disappear. This gradient is the driving force for other transport proteins, such as the sodium-calcium exchanger, which plays an important role in cardiomyocytes. To make muscle contraction possible, a calcium influx from the extracellular fluid into the cell is crucial. After the muscle contraction, the calcium is normally pumped out of the cell and exchanged for sodium. When the sodium gradient is depleted, calcium cannot be pumped back and, as a consequence, accumulates in the cardiomyocyte. As a result of the high calcium concentration, actin and myosin filaments will bind stronger, unable to relax properly to make a new contraction possible. This may result in cardiac arrhythmias, in the worst case decreasing cardiac output and causing a shortage in oxygen supply in vital tissues. Apart from being a potent toxic compound, it may also be used in therapeutic ways. Both oleandrin and oleandrigenin, as well as their relatives, may be able to inhibit proliferation of tumor cells and stimulate their apoptosis as a result of the high concentration of intracellular calcium. In addition, it inhibits excretion of fibroblast growth factor 2 through membrane interaction and through inhibition of the Na,K-ATPase pump. However, there are no results from clinical testing on humans that support any use as a cancer treatment. Oleandrin has been reported to be lethal, but exact dosages are not fully documented. The fatal blood concentration of oleandrin has been estimated for humans to be approximately 20 ng/ml in decreased blood by extrapolation of intoxication symptoms. Symptoms present in poisoned animals include bloody diarrhea and colic, the latter especially in horses. Because the leaf itself is quite bitter, only starving animals will be likely to eat the plant. The lethal dosage for animals is estimated to be about 0.5 mg/kg.

Puerarin (7, 4’-dihydroxyisolavone-8-β-glucopyranoside) is an active isoflavone extracted from the roots of Pueraria lobata (Willd.) Ohwi. Puerarin is widely used in traditional Chinese medicine, and is clinically used in China for the treatment of coronary artery disease, heart failure, hypertension and myocardial infarction. It has been reported that puerarin had therapeutic effects on diabetes mellitus, arteriosclerosis and myocardial ischemia in animals. Puerarin demonstrated beta-adrenergic receptor blocking effect. On the other hand, puerarin stimulated alpha1-adrenoreceptor to increase glucose uptake into cultured C2C12 cells of mice. Puerarin has been investigated for the treatment (phase II clinical trials) of Alcohol Abuse, Rheumatoid Arthritis and Hypertension.

PF-05089771 is an oral administrated Nav1.7 channel inhibitor. PF-05089771 provided the best opportunity to explore Nav1.7 blockade for the treatment of acute or chronic pain conditions. PF-05089771 has completed Phase II clinical trials of third molar extraction and primary inherited erythromelalgia. The magnitude of efficacy of PF-05089771 in the randomized, placebo-controlled, double-blind clinical study in subjects with painful diabetic peripheral neuropathy was disappointing. Although there was a trend towards a reduction in pain and improvement in sleep rating in patients with painful DPN when compared to placebo treatment, this was not statistically significant.

Chlorogenic acid is the ester of caffeic acid and (-)-quinic acid. Chlorogenic acid is a naturally occurring plant metabolite and can be found with the related compounds cryptochlorgenic acid and neochlorogenic acid in the leaves of Hibiscus sabdariffa, coffee, potato, eggplant, peaches, and prunes. Chlorogenic acid has been investigated as a dietary supplement to improve glucose intolerant hypoglycemia and non-alcoholic fatty liver disease. It has also been identified as a potential anticancer agent by reducing the expression of HIF-1a and Sphingosine Kinase-1. Chlorogenic acid was also identified as a neuraminidase blocker effective against influenza A virus (H1N1 and H3N2).

Dexniguldipine (B8509-035, (-)-(R)-niguldipine) is a new dihydropyridine derivative, that exerts selective antiproliferative activity in a variety of tumor models and, in addition, has a high potency in overcoming multidrug resistance. Dexniguldipine is ( - )-(R)-enantiomer of niguldipine, of which the ( )-(S)-enantiomer shows pronounced cardiovascular hypotensive activity due to its high affinity for the voltage-dependent Ca2 channel. As compared with the (S)-enantiomer, the (R)-enantiomer has a 40-fold lower affinity for the Ca 2 channel and, accordingly, only minimal hypotensive activity in animal pharmacology models. Dexniguldipine have shown antiproliferative activity in several tumor cell lines, but the concentrations necessary to inhibit growth have varied by several orders of magnitude between cell lines. Initial results of preclinical investigations for the evaluation of the mechanism of its antiproliferative activity demonstrate that dexniguldipine interferes with intracellular signal transduction by affecting phosphoinositol pathways, protein kinase C expression, and intracellular Ca 2 metabolism. In a series of human tumor xenografts in vitro, dexniguldipine demonstrated selective antiproliferative activity against several tumor types, e.g., melanoma and renal-cell carcinoma. Striking results were obtained in a hamster model, in which neuroendocrine lung tumors could be completely eradicated by 20 weeks of oral treatment with 32.5mg/kg dexniguldipine, whereas Clara-cell-type lung tumors were not affected. In in vitro studies, dexniguldipine has been found to bind to P-glycoprotein (P-gp) and to enhance the cytotoxicity of chemotherapeutic agents such as doxorubicin and etoposide in several cell lines The synergistic effect may well be associated with the reversal of multidrug resistance (MDR) related to the activity of P-gp. In the clinical therapy of cancer, resistance to many cytostatic drugs is a major cause of treatment failure. However, the high potency of dexniguldipine (about 10-fold as compared with that of verapamil in vitro) and its low cardiovascular activity provide the opportunity to achieve blood or tumor concentrations that might be high enough to overcome Mdr 1 resistance in patients without producing dose-limiting cardiovascular effects.

Risotilide is a Class III antiarrhythmic agent that inhibits the voltage-dependent potassium channel. Risotilide prolongs cardiac action potentials and refractory periods. It was shown to reduce ventricular vulnerability in a study on arrhythmogenic effects of left ventricular hypertrophy (LVH) in the intact heart in cats. Phase I and II trials have been conducted, but development of this drug has been discontinued.

Raxatrigine also known as GSK1014802 and CNV-1014802, is a novel analgesic under development by Convergence Pharmaceuticals for the treatment of lumbosacral radiculopathy (sciatica) and trigeminal neuralgia (TGN). It is a novel state dependent small molecule sodium channel blocker that preferentially inhibits the Nav 1.7 ion channel, a therapeutic target implicated by genetics in human pain conditions. Raxatrigine is thought to penetrate the central nervous system and block Nav channels in a novel manner. CNV1014802 was granted orphan drug designation in 2013 by the US Food and Drug Administration (FDA) for the treatment of trigeminal neuralgia.