of two major clinical trials this year—one called Bloom back in March, and another called Blossom last month. The Bloom study enrolled 3,182 patients, and Blossom enrolled 4,008, so this combined database is what Arena plans to package together in its application to the FDA by the end of this year. Arena hasn’t yet said anything groundbreaking about the studies being presented at The Obesity Society, but I was curious what questions Lief and Behan were getting most often from physicians at the conference.
Unlike investors, who tend to focus on the percentage of body weight loss in relation to placebo, the doctors wanted to know how many pounds lorcaserin patients actually lost. The quick answer to that was 17.9 pounds on average for patients who stayed on lorcaserin a full year in the Bloom study, compared with 7.3 pounds in the placebo group. The Blossom study confirmed that figure, with 17 pounds of average weight loss among those who stayed on the drug a full year, compared with 8.7 pounds on the placebo.
The average weight loss numbers were more modest when researchers factored in the total patient population, including almost half of patients who dropped out early.
Even though Arena is maneuvering its drug so that it stands out for safety first, and its ability to help improve diabetic and cardiovascular health markers, Lief definitely doesn’t want to cede too much ground to his rivals when the discussion turns to raw weight loss. That’s going to be a big part of the equation that the FDA considers—along with safety—when it combs through all of the new drug applications. And so will doctors.
“Investors have it all wrong when they think lorcaserin had modest efficacy. It’s not true,” Lief says. “This is not a wimpy weight loss drug. It’s an effective agent.”
