Roche begins New Phase 2 Fragile X Clinical Trial in the US

Roche begins New Phase 2 Fragile X Clinical Trial in the US
February 1, 2010

Longtime FRAXA members will recall that we've been talking about the promise of mGluR5 drugs to treat Fragile X for years. Ever since FRAXA Postdoctoral Fellow Dr. Kim Huber made the original finding in Mark Bear's lab at Brown University in 2000, FRAXA has been working nonstop to organize and fund the pivotal preclinical research which has validated these drugs as treatments for Fragile X.

Starting in 2001, FRAXA organized a concerted effort in university labs around the world to confirm Mark Bear's mGluR Theory of Fragile X and to demonstrate to pharmaceutical companies that mGluR5 antagonists have specific therapeutic effects for Fragile X. This strategy has exceeded expectations: Swiss pharmaceutical giant Hoffmann-LaRoche (also known as "Roche") has begun US trials of their lead mGluR5 antagonist, RO4917523, for Fragile X. See for details.

There are now four pharmaceutical companies in active clinical trials of mGluR5 antagonists for a Fragile X indication: Neuropharm, Novartis, Seaside Therapeutics and Roche. Multiple development programs are essential to FRAXA's goal of bringing new Fragile X treatments to patients, because any one drug faces many risks in the long journey to FDA approval. The fact that many companies are also developing drugs in this class for other indications (like Parkinson's Disease) means that it is even more likely that one mGluR5 antagonist will be available in the not-too-distant future.

To summarize the progress to date:


  • Roche has started the first US multiple-dose trial of an mGluR5 antagonist, at sites around the country (a Phase II trial).
  • Novartis completed its first Phase II trial of an mGluR5 antagonist for Fragile X in Europe last summer and they are proceeding ahead with more trials.
  • Seaside Therapeutics recently completed Phase I of its lead mGluR5 antagonist, licensed from Merck, and is now preparing for Phase II in the US this spring. Seaside has also just finished a Phase II trial of arbaclofen in patients with Fragile X and autism and is planning for Phase III.
  • Neuropharm, which completed the first ever trial of an mGluR5 antagonist, fenobam, in patients with Fragile X, is planning follow up trials.


FRAXA continues to work with these companies and others. We are certain that more trials are coming soon, with mGluR-based treatments, as well as other therapeutic strategies.