Arena cleared to continue obesity drug trial
Arena Pharmaceuticals, following a planned review by an independent Echocardiographic Data Safety Monitoring Board, said it is continuing its BLOOM trial, which is evaluating the efficacy and safety of lorcaserin hydrochloride for the treatment of obesity.

The drug’s safety is being closely watched because Arena’s lorcaserin bears similarities to Wyeth’s diet drugs, Redux or Pondimin, which were used with Phentermine as the once popular fen-phen weight-loss combination, and pulled from the market about 10 years ago, after being linked to heart-valve damage, according the Dow Jones Newswire.

The Echocardiographic Data Safety Monitoring Board’s (EDSMB) review of unblinded echocardiographic data performed after patients completed 12 months of dosing in the trial confirmed that differences, if any, in the rates of FDA-defined valvulopathy in patients treated with lorcaserin and in the control group did not meet the board's predetermined stopping criteria, according to the San Diego-based company.

Based on the EDSMB's review of the rate of FDA-defined valvulopathy, Arena said it has been able to confirm that the statistical power calculations used in the design of the Phase 3 trial program to monitor patients for increased risk of developing valvulopathy are justified. The company also said the findings from the 12-month review build on the EDSMB's September 2007 review that evaluated echocardiograms after six months of dosing.

“The 12-month data substantially de-risks the lorcaserin development program and should place [Arena] in a stronger position to negotiate a major commercialization partnership for the drug,” Oppenheimer analyst Bret Holley told Dow Jones.

BLOOM (Behavioral modification and Lorcaserin for Overweight and Obesity Management), the first of three lorcaserin Phase 3 trials, is a double-blind, randomized, placebo-controlled trial involving nearly 3,200 patients in approximately 100 centers throughout the U.S., according to Arena.

The trial is evaluating a 20 mg daily dose (10 mg dosed twice daily) of lorcaserin versus placebo over a two-year treatment period in obese patients with a body mass index (BMI) of 30 to 45 with or without co-morbid conditions and overweight patients (BMI 27 to less than 30) with at least one co-morbid condition.

“We believe that this exposure duration, even under a conservative interpretation of the literature, would have been sufficient to observe a fenfluramine like effect on heart valves if present," said Jack Lief, Arena's president and CEO.

“Heart valve problems were observed in fen-phen trials as early after six months of use, Matthew Osborne, Lazard Capital Markets analyst, confirms with Dow Jones. Osborne warned that the safety review is important, but doesn't rule out potential long-term safety concerns for lorcaserin. 

The results of the BLOOM trial are expected to be released a year from now.