Shares in Adamas Pharmaceuticals gained as much as 58.5 percent Wednesday after the company announced Phase III results demonstrating that the experimental compound ADS-5102, its long-acting capsule formulation of the antiviral amantadine, met the primary endpoint of significantly reducing levodopa-induced dyskinaesia (LID) associated with Parkinson's disease compared with placebo. CEO Gregory Went said the top-line results "confirm and extend the positive findings from our earlier randomised placebo-controlled study," adding that "with these data in hand, we look forward to talking with the FDA about our planned [new drug application] submission for ADS-5102" next year.
According to the company, efficacy analyses for the EASE LID study were based on a modified intent-to-treat population of 121 moderate-to-advanced Parkinson's disease patients with LID. Patients were randomised to treatment with ADS-5102 or placebo once daily for 24 weeks. The primary efficacy endpoint was the reduction in LID over 12 weeks as evaluated using the Unified Dyskinesia Rating Scale, while secondary goals included a reduction in LID over 24 weeks and changes in a standardised Parkinson's disease diary, including periods of "on time" without troublesome dyskinaesia, as well as "off time," at weeks 12 and 24.
Results from the study illustrated that treatment with ADS-5102 was associated with a 23-percent reduction in LID versus placebo at 12 weeks, with the effect maintained at 24 weeks. Adamas noted that ADS-5102 also significantly increased "on time" by 2.7 hours versus placebo and reduced "off time" by 0.9 hours, effects that were maintained at week 24.
Moreover, Adamas said adverse events associated with ADS-5102 were "consistent" with the known safety profile of amantadine, as well as the safety results from the company's earlier placebo-controlled trial. Specifically, there were 17 severe adverse events reported in the EASE LID trial involving 13 ADS-5102-treated patients and four in the placebo group, with three events in the ADS-5102 arm and one event in the placebo group deemed to be study-drug related. Adamas stated that comprehensive data from the EASE LID trial will be presented at a future research meeting.
Went suggested that his company is committed to marketing ADS-5102 itself if it succeeds in gaining approval. The drug, which is also undergoing mid-stage testingin patients with multiple sclerosis who have walking impairment, was granted orphan drug status in the US in April for LID associated with Parkinson's disease. Meanwhile, Osmotica Pharmaceutical is testing Osmolex ER, its own extended-release version of amantadine, as a potential treatment for the levodopa-induced side effect in a Phase II trial. The company has said it anticipates filing Osmolex for US approval in 2016.
