The trial was a randomized, double-blind, three-arm placebo-controlled study, the primary endpoint of which was change from baseline to week six on the positive and negative syndrome scale (PANSS).
The novel antipsychotic, RGH-188, demonstrated a nominally statistically significant (not adjusted for multiple comparisons) therapeutic effect compared to placebo in the treatment of schizophrenia in the low-dose arm, but a numerical improvement compared to placebo in the high-dose arm that did not reach nominal statistical significance.
RGH-188 was generally well tolerated and overall premature discontinuation rates (all causes including adverse event related) were 47% for patients receiving a low dose of RGH-188, 46% for patients receiving a high dose of RGH-188, and 47% for patients receiving placebo.
Based on the initial positive results for one of the active dosing arms and subject to a complete review of the full study results for the just completed trial, the companies intend to continue the development of RGH-188 as a treatment for schizophrenia, and will determine the appropriate development activities over the coming months.