Panamesine (; developmental code name EMD-57455) is a

sigma receptor Sigma receptors (σ-receptors) are protein receptors that bind ligands such as 4-PPBP (4-phenyl-1-(4-phenylbutyl) piperidine), SA 4503 (cutamesine), ditolylguanidine, dimethyltryptamine, and siramesine. There are two subtypes, sigma-1 rec ...

antagonist An antagonist is a character in a story who is presented as the main enemy or rival of the protagonist and is often depicted as a villain.Merck as a potential

antipsychotic Antipsychotics, previously known as neuroleptics and major tranquilizers, are a class of Psychiatric medication, psychotropic medication primarily used to manage psychosis (including delusions, hallucinations, paranoia or disordered thought), p ...

for the treatment of

schizophrenia Schizophrenia () is a mental disorder characterized variously by hallucinations (typically, Auditory hallucination#Schizophrenia, hearing voices), delusions, thought disorder, disorganized thinking and behavior, and Reduced affect display, f ...

in the 1990s but was never marketed. It is a selective antagonist of both sigma receptor subtypes, the σ₁ and σ₂ receptors ( IC₅₀ = 6 nM). In addition, the major

metabolite In biochemistry, a metabolite is an intermediate or end product of metabolism. The term is usually used for small molecules. Metabolites have various functions, including fuel, structure, signaling, stimulatory and inhibitory effects on enzymes, c ...

of the drug, EMD-59983, has high

affinity Affinity may refer to: Commerce, finance and law * Affinity (law), kinship by marriage * Affinity analysis, a market research and business management technique * Affinity Credit Union, a Saskatchewan-based credit union * Affinity Equity Pa ...

for the sigma receptors (IC₅₀ = 24 nM) and the

dopamine Dopamine (DA, a contraction of 3,4-dihydroxyphenethylamine) is a neuromodulatory molecule that plays several important roles in cells. It is an organic chemical of the catecholamine and phenethylamine families. It is an amine synthesized ...

D₂ (IC₅₀ = 23 nM) and D₃ receptors, with potent antidopaminergic activity. Panamesine reached phase II

clinical trial Clinical trials are prospective biomedical or behavioral research studies on human subject research, human participants designed to answer specific questions about biomedical or behavioral interventions, including new treatments (such as novel v ...

s for schizophrenia prior to the discontinuation of its development. CNS review:

References

Abandoned drugs Tertiary alcohols Antipsychotics Benzodioxoles D2 antagonists D3 antagonists Ketones Oxazolidines 4-Phenylpiperidines Sigma antagonists {{nervous-system-drug-stub

See also

References