Disappointing Results Reported for Schizophrenia Drug Bitopertin in Late-Stage Trials
Treatment fails to improve negative symptoms (January 21)
Two phase III studies of the investigational medication bitopertin (RG1678, Roche) in adults with persistent, predominant negative symptoms of schizophrenia failed to meet their primary endpoints, based on the negative symptoms factor score of the positive and negative symptom scale (PANSS). Negative symptoms include social withdrawal and lack of motivation.
In the studies, adding bitopertin to antipsychotic therapy did not significantly reduce negative symptoms at 24 weeks compared with placebo.
A third phase III trial evaluating bitopertin for persistent, predominant negative symptoms of schizophrenia is ongoing. In addition, three phase III studies investigating bitopertin for suboptimally controlled symptoms of schizophrenia are in progress. Suboptimally controlled symptoms, such as hallucinations and delusions, are symptoms that do not resolve despite treatment with an antipsychotic.
Bitopertin is an oral glycine reuptake inhibitor that may improve N-methyl-D aspartate (NMDA) receptor function, which is thought to be reduced in schizophrenia, by increasing the availability of glycine for receptor activation. Reduced NMDA receptor function may contribute to all core symptom types of schizophrenia.
Source: Roche; January 21, 2014.