Hoping to convince the FDA that it has all the data needed to warrant an approval for its experimental weight drug lorcaserin, Arena Pharmaceuticals ($ARNA) unleashed a batch of new results from its 600-patient study of the treatment. But while the study hit one of the agency's two standards on weight loss needed for an approval--and only one is required--the developer failed to achieve any general consensus that it won't need considerably more study data to persuade a wary FDA the drug is safe and effective.
On the plus side, one-year data from the study found that 37.5 percent of diabetics taking a twice-daily dose lost at least five percent of their body weight compared to the 16.1 percent of patients in the placebo arm, hitting an essential regulatory goal. There was a mean weight loss of 4.5 percent in the drug arm compared to a 1.5 percent drop in the sugar pill group--not a big enough spread to hit the agency's standards. Investigators also found that 2.9 percent of patients had a problem with their heart valves compared to 0.5 percent in the placebo group.
"We're confident, and so is Eisai, that lorcaserin is approvable," Arena CEO Jack Lief told Bloomberg. "It's not a question of if, but when."
The FDA recently rejected Arena's initial application for approval after questioning the drug's efficacy and raising questions about the safety problems presented by signs of cancer in a rat study. And the initial reaction to the new data left plenty of room for doubt about Arena's chances of persuading regulators that lorcaserin is worthy of a near-term approval.
Dow Jones noted that it is "unclear if the findings are strong enough to help the drug get regulatory approval." And TheStreet went one step further, with Adam Feuerstein noting that the evidence of heart valve issues "alarmingly" raises a new safety issue for an agency that has signaled it is leery of taking any risks with an obesity drug. And Feuerstein adds that there's nothing new in this fresh data drop that will change regulators' perception about the drug's "marginal" efficacy rate.