ACADIA Pharmaceuticals Inc.

About: ACADIA Pharmaceuticals Inc. is a company organization based out in San Diego, California, United States. It is known for research contribution in the topics: Pimavanserin & Receptor. The organization has 260 authors who have published 276 publications receiving 8418 citations.

Pimavanserin, a 5-HT2A inverse agonist, reverses psychosis-like behaviors in a rodent model of Parkinson's disease.

Abstract: Parkinson's disease psychosis (PDP) is a condition for which a safe, tolerated, and effective therapy is lacking. Treatment with typical or atypical antipsychotics may be contraindicated in patients with PDP because of the potential for aggravating motor symptoms. This study used a novel animal model with features of both Parkinson's disease (PD) and psychosis to examine a potential mechanism for reversing PDP. Animals with bilateral 6-hydroxydopamine lesions of the substantia nigra displayed motoric impairments characteristic of humans with PD. In addition, they displayed augmented head twitches, augmented amphetamine-induced locomotor activity, and disrupted prepulse inhibition compared with sham controls, behavioral indices frequently used to assess antipsychotic activity in animal models. Pimavanserin, a selective 5-HT2A antagonist/inverse agonist, reversed the psychotic-like behavioral deficits, suggesting that nigrostriatal (6-hydroxydopamine) lesions induced alterations in 5-HT2A-mediated signaling. The selective 5-HT2A inverse agonist M100907, but not the selective 5-HT2C inverse agonist SB 252084 paralleled the effects of pimavanserin. Of note, the reversal of psychotic-like behaviors produced by 5-HT2A inverse agonists occurred without disrupting motor behaviors in lesioned subjects, suggesting that 5HT2A antagonism/inverse agonism may be beneficial in the treatment of PDP.

Pimavanserin: Potential Treatment For Dementia-Related Psychosis.

Abstract: Psychosis is common across dementia types with a prevalence of 20% to 70% Currently, no pharmacologic treatment is approved for dementia-related psychosis Atypical antipsychotics are frequently used to treat these disorders, despite significant safety concerns Pimavanserin, a selective 5-HT2A inverse agonist/antagonist, was approved in the US for treating hallucinations and delusions associated with Parkinson's disease psychosis (PDP) Patients in the pimavanserin group experienced a significant (p=0001) improvement in Scale for the Assessment of Positive Symptoms - Parkinson's disease (SAPS-PD) scores vs placebo In a subgroup analysis of patients with cognitive impairment (MMSE score ≥21 but ≤24), the observed improvement on the SAPS-PD with pimavanserin (N=50) was also significant (p=0002) and larger than in the overall study population without an adverse effect on cognition In a Phase 2 study with pimavanserin in Alzheimer's disease psychosis, pimavanserin significantly (p=0045) improved psychosis at Week 6 vs placebo on the NPI-NH Psychosis Score (PS) In a prespecified subgroup of patients with a baseline NPI-NH PS ≥12, a substantively larger treatment effect (p=0011) was observed vs participants with NPI-NH PS <12 The results of these studies in cognitively impaired patients with PDP provided the scientific foundation for an ongoing study of pimavanserin for treating patients with dementia-related psychosis associated with the most common neurodegenerative disorders The study uses a relapse-prevention design with the endpoint of time-to-relapse of psychosis to evaluate the long-term efficacy and safety of pimavanserin as a potential treatment for hallucinations and delusions of dementia-related psychosis

Reactions between Grignard reagents and heterocyclic N-oxides: Stereoselective synthesis of substituted pyridines, piperidines, and piperazines

Abstract: In this perspective we discuss the recent developments of stereoselective synthesis of substituted pyridines, piperidines, and piperazines from cheap and commercially readily available starting materials. Pyridine N-oxides and pyrazine N-oxides are reacted with alkyl, aryl, alkynyl and vinyl Grignard reagents to give a diverse set of heterocycles in high yields. Optically active substituted piperazines are obtained by an asymmetric reaction from pyrazine N-oxides using sparteine as chiral ligand. In addition, a stereoselective synthesis of dienal-oximes from the reaction between pyridine N-oxides and Grignard reagents is presented, which results in a useful intermediate for the synthesis of a diverse set of compounds.

Identification and Characterization of Novel Small-Molecule Protease-Activated Receptor 2 Agonists

Abstract: We report the first small-molecule protease-activated receptor (PAR) 2 agonists, AC-55541 [ N -[[1-(3-bromo-phenyl)-eth-( E )-ylidene-hydrazinocarbonyl]-(4-oxo-3,4-dihydro-phthalazin-1-yl)-methyl]-benzamide] and AC-264613 [2-oxo-4-phenylpyrrolidine-3-carboxylic acid [1-(3-bromo-phenyl)-( E / Z )-ethylidene]-hydrazide], each representing a distinct chemical series. AC-55541 and AC-264613 each activated PAR2 signaling in cellular proliferation assays, phosphatidylinositol hydrolysis assays, and Ca 2+ mobilization assays, with potencies ranging from 200 to 1000 nM for AC-55541 and 30 to 100 nM for AC-264613. In comparison, the PAR2-activating peptide 2-furoyl-LIGRLO-NH 2 had similar potency, whereas SLIGRL-NH 2 was 30 to 300 times less potent. Neither AC-55541 nor AC-264613 had activity at any of the other PAR receptor subtypes, nor did they have any significant affinity for over 30 other molecular targets involved in nociception. Visualization of EYFP-tagged PAR2 receptors showed that each compound stimulated internalization of PAR2 receptors. AC-55541 and AC-264613 were well absorbed when administered intraperitoneally to rats, each reaching micromolar peak plasma concentrations. AC-55541 and AC-264613 were each stable to metabolism by liver microsomes and maintained sustained exposure in rats, with elimination half-lives of 6.1 and 2.5 h, respectively. Intrapaw administration of AC-55541 or AC-264613 elicited robust and persistent thermal hyperalgesia and edema. Coadministration of either a tachykinin 1 (neurokinin 1) receptor antagonist or a transient receptor potential vanilloid (TRPV) 1 antagonist completely blocked these effects. Systemic administration of either AC-55541 or AC-264613 produced a similar degree of hyperalgesia as was observed when the compounds were administered locally. These compounds represent novel small-molecule PAR2 agonists that will be useful in probing the physiological functions of PAR2 receptors.