By Nick Paul Taylor
Addex Therapeutics’ attempt to expand use of dipraglurant into muscle spasms has stumbled at the first hurdle. A phase 2a clinical trial of the mGluR5 negative allosteric modulator has delivered “inconclusive” data in an eyelid disorder, raising doubts about a broader push beyond Parkinson’s disease.
The primary use case for dipraglurant is in levodopa-induced dyskinesia in Parkinson’s, an indication Addex is evaluating in a phase 3 clinical trial that is due to report data in the first half of next year. While working to seize the Parkinson’s opportunity, Addex identified the potential to use dipraglurant to treat muscle spasms, starting with an eyelid condition, blepharospasm, that can cause functional blindness.
To test the spasm hypothesis, Addex randomized 15 blepharospasm patients to receive placebo or one of two doses of dipraglurant. While mainly designed to evaluate the safety and tolerability of the 50-mg and 100-mg doses, the study also gathered data on changes in blinking and spasms across a range of other endpoints. Safety was fine. Efficacy? Not so much.
