Arena Release Results of BLOOM-DM Trial on Lorcaserin


Arena Pharmaceuticals Inc released data from it’s Phase III BLOOM-DM trial earlier this week on lorcaserin hydrochloride, a weight-loss drug, which was rejected by the Food and Drug Administration (FDA) last month.

The FDA expects obesity drugs to show a minimal efficacy of either 5% placebo-adjusted weight loss or twice as many patients losing 5% of their weight on drug vs. placebo.

Lorcaserin has failed to do so in the first two Phase III trials, BLOOM and BLOSSOM, achieving placebo-adjusted weight loss of 3.6% and 3.1%, respectively.

Even in the latest trial, Lorcaserin has failed in one aspect to meet the minimal FDA expected efficacy. In the BLOOM-DM trial, at week 52 lorcaserin patients achieved 4.5% mean weight loss compared to 1.5% for placebo, resulting in placebo-adjusted weight loss of 3%.


The BLOOM-DM study which evaluated 604 obese and overweight patients with type 2 diabetes. Patients were randomized to lorcaserin 10 mg BID (N=256), lorcaserin 10 mg dosed once daily (N=95) or placebo (N=253). To expedite enrollment, randomization to the lorcaserin 10 mg QD dose was discontinued after approximately 300 patients were enrolled in the trial.

Lorcaserin did met the FDA minimal efficacy of twice as many patients losing 5% of their weight vs those on the placebo (37.5% of patients treated with lorcaserin 10 mg BID compared to 16.1% of patients taking placebo).

The most frequent adverse events were headache, upper respiratory infection, back pain and nasopharyngitis. Arena also said 2.9 percent of lorcaserin patients and 0.5 percent of placebo patients had new valvulopathy at week 52, although the study was not powered to detect meaningful differences in valvulopathy.

Arena and partner Eisai Inc. have a meeting with the FDA scheduled to discuss the complete response letter before the end of the year.

Arena Pharmaceutical Press Release
Food and Drug Administration