A phase 3 clinical trial of Acorda Therapeutics’ inhaled formulation of levodopa has met its primary endpoint. The study linked the high dose of CVT-301 to a statistically significant improvement in scores on a Parkinson’s disease motor impairment scale, setting Acorda up to file for approval in the second quarter.
While Acorda is yet to share a full look at the data and is still waiting on readouts from two long-term safety studies, it sees the phase 3 efficacy results validating its intentions to file for approval in the U.S. and Europe by the end of the year. If that process goes as planned, it will go some way to justifying the $525 million cash buyout Acorda penned in 2014 to gain Civitas Therapeutics and its phase 3 candidate CVT-301, a levodopa formulation designed to offer faster symptom control than tablets.
The phase 3 enrolled 339 participants who were on a stable regimen of oral carbidopa/levodopa and randomized them to receive one of two doses of CVT-301 or a placebo. Subjects self-delivered the inhaled formulation up to five times a day for 12 weeks, after which investigators looked at changes to Unified Parkinson’s Disease Rating Scale-Part 3 (UPDRS III) compared to baseline. The hope was that CVT-301 would help patients cope with “off” periods when their symptoms re-emerge.
UPDRS III scores in participants who received the higher 84 mg dose improved by -9.83, compared to a change of -5.91 among subjects in the placebo cohort. That resulted in a treatment effect of 3.92, a figure large enough to achieve statistical significance but smaller than that generated in the phase 2b. Acorda is yet to say how the lower dose of CVT-301 fared, or how either dose performed against secondary efficacy endpoints.
Serious adverse events were rare across the trial. The 5.3% rate seen in the 60 mg CVT-301 cohort was the highest incidence of serious adverse events. Less severe events were more common, with 15% of participants in the treatment arms experiencing a cough. Three participants discontinued treatment because of a cough. More than 5% of participants in the 84 mg arm suffered from upper respiratory tract infection, nausea or discolored sputum. No notable pulmonary safety signals were seen.
Acorda is due to have 12-month data from the two long-term safety studies by the end of the quarter. Those results, coupled with a full breakdown of the phase 3 results, will give a clearer picture of whether Acorda can clear the upcoming regulatory hurdles and go on to rack up the $500 million in sales it is forecasting.
Shares in Acorda rose more than 10% in premarket trading.