BLOOM-DM was not powered to detect meaningful differences in the incidence of valvulopathy.

FORBES: Safety Data Worsens For Arena's Obesity Drug

This probably means that valvulopathy risk will get harder to rule out.

FORBES: Safety Data Worsens For Arena's Obesity Drug

But those results are outweighed by the safety result, which shows more patients on lorcaserin had heart valve problems, or valvulopathy, than those on placebo.

FORBES: Safety Data Worsens For Arena's Obesity Drug

In its two big trials, based on a note from analysts at Jefferies earlier this year, there were 58 cases of valvulopathy in 1553 patients on lorcaserin and 51 cases among 2398 patients on placebo.

FORBES: Safety Data Worsens For Arena's Obesity Drug

Valvulopathy has been the main safety worry for lorcaserin from the start, because the drug was designed to hit the same receptor as the diet drug fenfluramine, which was withdrawn because it caused heart valve damage.

FORBES: Safety Data Worsens For Arena's Obesity Drug

At Week 24, 2.5% of lorcaserin 10 mg BID patients and 1.9% of placebo patients had new valvulopathy (based on FDA criteria), and at Week 52, 2.9% of lorcaserin 10 mg BID patients and 0.5% of placebo patients had new valvulopathy.

FORBES: Safety Data Worsens For Arena's Obesity Drug

Messy, back of the envelope calculation: Assume that there were 200 patients in the active group at 24 weeks and 150 patients at 52, and 250 patients were on placebo at 24 weeks and 200 at 52, and you get something like 9 cases of valvulopathy on lorcaserin and 6 on placebo.

FORBES: Safety Data Worsens For Arena's Obesity Drug