Belanorib: Good Weight Loss Efficacy But Troubling VTE Risk
Yesterday, Zafgen released data from its phase 2b trial of beloranib in patients with severe obesity complicated by type 2 diabetes.
Zafgen recently announced that its phase 2b trial (ZAF-203) of the MetAP2 inhibitor beloranib in 152 patients with severe obesity complicated by type 2 diabetes.
Accompanying an impressive 12.7 and 13.5% weight loss on 1.8 mg and 1.2 mg beloranib (vs 3.1% for placebo), respectively.
Unfortunately, these results are marred by the ongoing concern over potential thrombogenic adverse effects.
Thus of the nine serious adverse events identified in eight patients during the trial, one was a pulmonary embolism in the 1.2 mg treatment group. A subsequent screening process (following the FDA’s partial clinical hold on the trial) identified silent pulmonay emboli in two additional patients in the beloranib treatment arms.
Currently Zafgen is working to better understand the potential mechanisms underlying the apparent thrombogenic risk as well as developing a risk-mitigation strategy (at least for studies in patients with Prader-Willi Syndrome) that would help resolve the complete clinical hold the FDA placed on the beloranib for now.
Thus, the future remains uncertain for what would otherwise certainly be a big step forward to fill the continuing gap of more effective medical treatments for obesity.
Disclaimer: I have received consulting honoraria from Zafgen, the makers of belanorib