Analysts frown as key Sanofi MS drug fails to beat rival

One of Sanofi's ($SNY) top drug prospects has failed to beat a rival treatment in a head-to-head study, signaling fresh clinical trouble for a Big Pharma company that had vowed to reinvent the development process. Investigators reported that Aubagio (teriflunomide), an oral MS therapy, was no more effective than Merck KGaA's older injectable Rebif.

For analysts, the news indicated that even if Aubagio goes on to an approval, Sanofi will find itself facing a bevy of competitors with possibly better claims to efficacy and safety. Biogen Idec ($BIIB) has been grabbing headlines with its data on oral BG-12 while Teva ($TEVA) has its own MS program in the race. Novartis ($NVS), meanwhile, beat everyone to the market with Gilenya. Sanofi also has Lemtrada in the clinic, another MS drug obtained in its acquisition of Genzyme.

"Aubagio has the advantage of being an oral treatment, but its potential will be limited by more efficacious drugs," Bryan, Garnier analyst Eric Le Berrigaud noted to Bloomberg ahead of the results today. "If there weren't other medicines like Gilenya, BG-12 and even Lemtrada, it would be a great product."

"The teriflunomide 14 mg daily dose (0.259) and Rebif (0.216) were not distinguishable on the endpoint of estimated annual relapse rate," Sanofi reported. "The rate was higher in the 7 mg arm (0.410). The percentage of patients experiencing any treatment emergent adverse events was similar across all arms of the study."

Sanofi has been recruiting more than 4,000 patients for its studies of Aubagio. The pharma company tapped the treatment as one of its top six drug prospects a little more than two months ago.

- here's the press release
- read the story from Bloomberg