11, april 2013

ACADIA Pharmaceuticals announced following its FDA meeting, it no longer needs to conduct additional Phase III trials for its pimavanserin drug for the treatment of Parkinson’s disease psychosis. The company plans to seek early approval for the drug.

ACADIA Pharmaceuticals Inc.  announced that the FDA has agreed that the data from the pivotal Phase III -020 study, together with supportive data from other studies with pimavanserin, are sufficient to support the filing of a New Drug Application, or NDA, for the treatment of Parkinson’s disease psychosis, or PDP. ACADIA will no longer conduct the Phase III -021 study that was planned as a confirmatory trial. ACADIA believes FDA decision will reduce substantially both the time and cost of the company’s PDP development program.

ACADIA is currently focused on completing the remaining elements of its pimavanserin PDP development program that are needed for submission of an NDA. ACADIA is currently targeting an NDA submission near the end of 2014.

Pimavanserin (ACP-103) is a drug developed by Acadia Pharmaceuticals which acts as an inverse agonist on the serotonin receptor subtype 5-HT_2A, with 10x selectivity over 5-HT_2C, and no significant affinity or activity at 5-HT_2B or dopamine receptors.^[1] As of September 3 2009, pimavanserin has not met expectations for Phase III clinical trials for the treatment of Parkinson’s disease psychosis,^[2] and is in Phase II trials for adjunctive treatment of schizophrenia alongside an antipsychotic medication.^[3] It is expected to improve the effectiveness and side effect profile of antipsychotics.^[4][5][6]

1.  Vanover KE, Weiner DM, Makhay M, Veinbergs I, Gardell LR, Lameh J, Del Tredici AL, Piu F, Schiffer HH, Ott TR, Burstein ES, Uldam AK, Thygesen MB, Schlienger N, Andersson CM, Son TY, Harvey SC, Powell SB, Geyer MA, Tolf BR, Brann MR, Davis RE (May 2006). “Pharmacological and behavioral profile of N-(4-fluorophenylmethyl)-N-(1-methylpiperidin-4-yl)-N’-(4-(2-methylpropyloxy)phenylmethyl) carbamide (2R,3R)-dihydroxybutanedioate (2:1) (ACP-103), a novel 5-hydroxytryptamine_2A receptor inverse agonist”. J Pharmacol Exp Ther 317 (2): 910–8. doi:10.1124/jpet.105.097006. PMID 16469866.
2. ACADIA Pharmaceuticals. “Treating Parkinson’s Disease – Clinical Trial Pimavanserin – ACADIA”. Retrieved 2009-04-11.^{[dead link]}
3.  “ACADIA Announces Positive Results From ACP-103 Phase II Schizophrenia Co-Therapy Trial” (Press release). ACADIA Pharmaceuticals. 2007-03-19. Retrieved 2009-04-11.
4.  Gardell LR, Vanover KE, Pounds L, Johnson RW, Barido R, Anderson GT, Veinbergs I, Dyssegaard A, Brunmark P, Tabatabaei A, Davis RE, Brann MR, Hacksell U, Bonhaus DW (August 2007). “ACP-103, a 5-hydroxytryptamine 2A receptor inverse agonist, improves the antipsychotic efficacy and side-effect profile of haloperidol and risperidone in experimental models”. J Pharmacol Exp Ther 322 (2): 862–70. doi:10.1124/jpet.107.121715. PMID 17519387.
5.  Vanover KE, Betz AJ, Weber SM, Bibbiani F, Kielaite A, Weiner DM, Davis RE, Chase TN, Salamone JD (October 2008). “A 5-HT2A receptor inverse agonist, ACP-103, reduces tremor in a rat model and levodopa-induced dyskinesias in a monkey model”. Pharmacol Biochem Behav 90 (4): 540–4. doi:10.1016/j.pbb.2008.04.010. PMC 2806670. PMID 18534670.
6.  Abbas A, Roth BL (December 2008). “Pimavanserin tartrate: a 5-HT2A inverse agonist with potential for treating various neuropsychiatric disorders”. Expert Opin Pharmacother 9 (18): 3251–9. doi:10.1517/14656560802532707. PMID 19040345.