Chelsea Therapeutics stunned analysts and investors this morning, reporting that a late-stage trial of its experimental neurological disorder drug Droxidopa failed to hit its primary endpoint. The drug has been approved and on the market in Japan for more than 10 years and analysts were eagerly awaiting what they thought would be clear signs of efficacy and safety.
Looking at the mean score of dizziness or light-headedness of the Orthostatic Hypotension Symptom Assessment, though, the therapy failed to produce a statistically significant result when compared to a placebo. And the market was ruthless in its response, swiftly lopping off close to three quarters of its share price.
The developer countered that nasty surprise by highlighting the drug's success on secondary endpoints. "If you look at the body of the data, I think it's clear that Droxidopa is helping patients," Chelsea CEO Simon Pedder tells FierceBiotech this morning. "There are definite efficacy signals. The FDA says we have to show symptomatic benefit, and we have that in a number of scales, just not in the primary." Further analysis will focus on the unexpected placebo effect and any other factors that may have played a role.
Pedder was also quick to point out that the results of a second Phase III trial will be unveiled in the fourth quarter. That trial is designed in a way likely to leave patients more sensitive to the drug's effect and help highlight its efficacy when compared to a placebo.
Investors had rapidly bid up Chelsea's share price in the last six months, expecting that new studies would underscore that Droxidopa would likely replace midodrine as the standard of care for a condition called neurogenic orthostatic hypotension, where a person's blood pressure drops when he stands up. Midodrine often causes blood pressure to spike when the patient lies down, but Droxidopa's safety profile has been clear. Analsyst have estimated peak U.S. sales of the drug at about $275 million.