1.A double-blind randomized study assessing safety and efficacy following one-year adjunctive treatment with bitopertin, a glycine reuptake inhibitor, in Japanese patients with schizophrenia.
Hirayasu Y1, Sato S2, Takahashi H3, Iida S3, Shuto N3, Yoshida S3, Funatogawa T3, Yamada T3, Higuchi T4. BMC Psychiatry. 2016 Mar 15;16(1):66. doi: 10.1186/s12888-016-0778-9.
BACKGROUND: Bitopertin, a glycine reuptake inhibitor, was investigated as a novel treatment for schizophrenia. We report all the results of a double-blind randomized study assessing safety and efficacy following 52-week adjunctive treatment with bitopertin in Japanese patients with schizophrenia.
2.Health-related quality of life in patients with prominent negative symptoms: results from a multicenter randomized Phase II trial on bitopertin.
Rofail D1, Regnault A2, le Scouiller S1, Berardo CG3, Umbricht D3, Fitzpatrick R4. Qual Life Res. 2016 Jan;25(1):201-11. doi: 10.1007/s11136-015-1057-9. Epub 2015 Jul 5.
PURPOSE: Symptoms of schizophrenia fall into three categories (positive, negative and cognitive symptoms), which probably impact differently on patient's health-related quality of life (HRQoL). The present study aimed to explore HRQoL in patients with prominent negative symptoms.
3.Physiologically based absorption modelling to predict the impact of drug properties on pharmacokinetics of bitopertin.
Parrott N1, Hainzl D, Scheubel E, Krimmer S, Boetsch C, Guerini E, Martin-Facklam M. AAPS J. 2014 Sep;16(5):1077-84. doi: 10.1208/s12248-014-9639-y. Epub 2014 Jun 27.
Bitopertin (RG1678) is a glycine reuptake inhibitor in phase 3 trials for treatment of schizophrenia. Its clinical oral pharmacokinetics is sensitive to changes in drug substance particle size and dosage form. Physiologically based pharmacokinetic (PBPK) absorption model simulations of the impact of changes in particle size and dosage form (either capsules, tablets, or an aqueous suspension) on oral pharmacokinetics was verified by comparison to measured plasma concentrations. Then, a model parameter sensitivity analysis was applied to set limits on the particle sizes included in tablets for the market. The model was also used to explore the in vitro to in vivo correlation. Simulated changes in oral pharmacokinetics caused by differences in particle size and dosage form were confirmed in two separate relative bioavailability studies. Model parameter sensitivity analyses predicted that AUCinf was hardly reduced as long as particle diameter (D50) remained smaller than 30 μm, and >20% reduced Cmax is anticipated only when particle diameter exceeds 15 μm.
4.Effects of Cytochrome P450 3A4 Inhibitors-Ketoconazole and Erythromycin-on Bitopertin Pharmacokinetics and Comparison with Physiologically Based Modelling Predictions.
Boetsch C1, Parrott N2, Fowler S2, Poirier A2, Hainzl D3, Banken L4, Martin-Facklam M5, Hofmann C1. Clin Pharmacokinet. 2016 Feb;55(2):237-47. doi: 10.1007/s40262-015-0312-0.
OBJECTIVE: To assess the effect of strong and moderate cytochrome P450 (CYP) 3A4 inhibition on exposure of bitopertin, a glycine reuptake inhibitor primarily metabolized by CYP3A4, and to compare the results with predictions based on physiologically based pharmacokinetic (PBPK) modelling.