The FDA Endocrinologic and Metabolic Drugs Advisory Committe turned down Arena Pharmaceutical and its partner Eisais propose for the weight-loss drug lorcaserin, based on a 9 to 5 vote against it. Arena shares fell nearly 40 percent in after-hours trading Thursday to $2.28.
The expert panel was not convinced that the current data could adequately demonstrate the potential benefits of lorcaserin outweighing the potential risks when used long-term in a large population of overweight and obese individuals.
The panelists raised concerns similar to that released by FDA staff earlier this week, mainly the results from Arenas Phase III clinical study did not meet mean efficacy criterion. The BLOOM trial indicated that patients on lorcaserin lost an average of 5.8% of body weight compared with 2.2% in the placebo arm. The expert panel also noted that studies of lorcaserin on rodent model showed breast tumours among those dosed at seven times higher than the proposed clinical dose for humans, but acknowledged that no such increase was seen in the 7,000 patients treated with the drug.
The committe called for more studies to be conducted in people with diabetes, high blood pressure and other health problems, therefore the trial result could reflect patients better if it was approved.
I just couldnt get over that we didnt have a broader population that was representative of people most likely to get this (drug), said Dr. Lamont Weide, an advisory panel member and chief of diabetes and endocrinology at the University of Missouri in Kansas City.
Arena was not totally downbeat after the news; Arena and Eisai believe that lorcaserin has a positive benefit-risk profile, said Arenas president and CEO, Jack Lief, in a statement. Eisai will sell lorcaserin in the US if the drug wins FDA approval. Arena will work closely with the FDA going forward, Lief said. The company has been studying lorcaserin in overweight and obese diabetics and said it expects results later this year.
The FDA will make its verdict by October 22, and usually FDA would follow panel recommendations.
Arena, Vivus and Orexigen are three companies struggling to win the first approval of a new weight-loss drug since Roches Xenical in 1999. Vivus Qnexa failed to gain the support from the EMDAC with a voted 10-6 against it; Orexigens Contrave (sustained-release naltrexone/bupropion) is scheduled to face the panels judgement later this year.