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

sigma receptor Sigma receptors (σ-receptors) are protein cell surface 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, ...

antagonist An antagonist is a character in a story who is presented as the chief foe of the protagonist. Etymology The English word antagonist comes from the Greek ἀνταγωνιστής – ''antagonistēs'', "opponent, competitor, villain, enemy, riv ...

that was under development by

Merck Merck refers primarily to the German Merck family and three companies founded by the family, including: * the Merck Group, a German chemical, pharmaceutical and life sciences company founded in 1668 ** Merck Serono (known as EMD Serono in the Unite ...

as a potential

antipsychotic Antipsychotics, also known as neuroleptics, are a class of Psychiatric medication, psychotropic medication primarily used to manage psychosis (including delusions, hallucinations, paranoia or disordered thought), principally in schizophrenia but ...

for the treatment of

schizophrenia Schizophrenia is a mental disorder characterized by continuous or relapsing episodes of psychosis. Major symptoms include hallucinations (typically hearing voices), delusions, and disorganized thinking. Other symptoms include social withdra ...

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 Partn ...

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 compound, organic chemical of the catecholamine and phenethylamine families. Dopamine const ...

D₂ (IC₅₀ = 23 nM) and D₃ receptors, with potent

antidopaminergic A dopamine antagonist, also known as an anti-dopaminergic and a dopamine receptor antagonist (DRA), is a type of drug which blocks dopamine receptors by receptor antagonism. Most antipsychotics are dopamine antagonists, and as such they have ...

activity. Panamesine reached phase II

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

s for schizophrenia prior to the discontinuation of its development.

References

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

See also

References