Fate of Transcept's sole clinical project hangs in balance after missed endpoint
This article was originally published in Scrip
Transcept Pharmaceuticals will outline the future - or demise - of TO-2061 (ondansetron oral tablets 0.5mg and 0.75mg) in early 2013 in response to the add-on therapy's missed primary efficacy endpoint in a Phase II clinical trial, which looked for an improvement in obsessive compulsive disorder (OCD) symptoms versus placebo.
Glenn Oclassen, president and CEO of Point Richmond, California-based Transcept, said in a statement from the company that it would "determine next steps, if any, in the clinical development program for TO-2061" - its only product in the clinic - after the completion of protocol-specified analyses from the trial, which enrolled OCD patients with inadequate responses to approved first-line therapies.
The investigational drug is a low-dose formulation of ondansetron - a serotonin subtype 3 (5-HT3) receptor antagonist - that Transcept designed as an adjunct to approved OCD drugs.
Ondansetron currently is approved to treat nausea and vomiting caused by chemotherapy and radiation, and to prevent postsurgical nausea and vomiting at daily doses that typically range from 16mg to 24mg. TO-2061 was dosed at 1mg to 1.5mg daily in the Phase II study.
The clinical trial was designed so that 168 patients with a documented history of at least six weeks of inadequate response to an approved OCD drug continued to receive their first-line medications during an additional six-week run-in phase of the trial. Patients who still did not respond during the run-in phase were eligible to be randomized to the 12-week double-blind active treatment phase, during which twice-daily treatments with ondansetron 0.5mg or 0.75mg or placebo were added to their first-line drugs.
The primary endpoint was the difference between the TO-2061 and placebo arms of the study in terms of the change from baseline as measured by the 10-item, clinician-administered Yale-Brown Obsessive Compulsive Scale (Y-BOCS).
In addition to TO-2061, Transcept has developed the sleep drug Intermezzo (zolpidem tartrate) sublingual tablet C-IV, which was approved by the US FDA in November 2011 as the only drug in the US that can be prescribed to help patients get back to sleep as needed if they wake up in the middle of night following treatment with a nightly prescription sleep aid (scripintelligence.com, 24 November 2011).
Purdue Pharma holds the US commercialization and development rights to Intermezzo and the two companies announced in late November that they would initiate a direct-to-consumer marketing campaign to boost low sales of the middle-of-the-night insomnia drug (scripintelligence.com, 28 November 2012).