In the study – a randomized, double-blind, placebo-controlled clinical trial – patients were assigned to four weeks of treatment with either Lilly's investigational compound LY2140023; olanzapine, an atypical antipsychotic medication that targets dopamine and serotonin receptors as an active control; or placebo.
The study demonstrated that LY2140023 and olanzapine showed statistically significant improvement versus placebo in PANSS (Positive and Negative Syndrome Scale), the most common scale used for measuring symptoms of patients with schizophrenia. Both groups showed a rapid response, within one week.
However, treatment with LY2140023 was not observed to have certain adverse events that often occur with currently approved schizophrenia medications, including increased prolactin elevations, extrapyramidal symptoms (involuntary movements or muscle stiffness), or weight gain.
Overall, LY2140023 40mg given twice daily was found to be safe and well-tolerated, with most adverse events being mild-to-moderate in severity and not treatment-limiting.
“These data provide compelling new evidence that mGlu2/3 receptor agonists have antipsychotic properties and may provide a completely new therapeutic approach for treating schizophrenia and, perhaps, other neuropsychiatric disorders,” said Steven Paul, Lilly's executive vice president of science and technology.
“Additional and longer-term studies are needed to confirm and extend these exciting initial findings. However, these data suggest that LY2140023 may provide a new alternative for the treatment of this often devastating condition.”