La Jolla’s Auspex Pharmaceuticals (Nasdaq: ASPX) has signed up the planned 90 patients for its Phase 3 clinical trial of SD-809, a potential treatment of chorea associated with Huntington's disease.
The company expects to announce topline data from the trial before the end of the year.
Chorea, a disorder involving involuntary movements of the body, is a primary feature of Huntington’s disease, although other forms of chorea can be associated with such things as rheumatic fever, reactions to drugs and complications of pregnancy.
In addition to the clinical trials aimed at gaining approval from the Food and Drug Administration, Auspex has also initiated an open-label clinical trial with the nonprofit Huntington Study Group to evaluate the long-term safety of SD-809, as well as provide guidance on how to switch patients who are currently using tetrabenazine to treat chorea.
The FDA approved tetrabenazine for Huntington’s-related chorea in 2008 -- making it the only drug to gain approval for the ailment so far -- but its side effects can include depression, dizziness, drowsiness, insomnia, fatigue and restless pacing. The risk of depression, which has been reported in roughly 15 percent of users, is so high that patients with a history of depression are warned not to take the drug.
In previous tests, the side effects to SD-809 were described as "mild to moderate," including dry eye and dry mouth in one patient and back pain in another. The company is currently planning Phase 1 tests for using the drug to treat Tourette's syndrome and Phase 2/3 tests for treating Tardive dyskenisia, a side-effect of antipsychotic drugs. Both are currently treated by tetrabenazine.