UPDATE: The FDA on Wednesday put a "complete hold" on Zafgen's trials for beloranib following the second patient death announced by the company that same day. The firm's shares slid another 4% in early morning trading.
Investigators will now begin assessing whether there are serious safety concerns associated with the drug, and their findings may doom any hopes the investigational compound had for regulatory clearance.
One concerning aspect of this particular patient death is the fact that the patient had actually undergone safety screening prior to entering the study and had been cleared to go.
- Zafgen on Wednesday unveiled that a second patient being treated with the investigational beloranib, the company's sole clinical stage drug, has died from blood clots that formed in the lungs.
- Beloranib is in development for the treatment of Prader-Willi syndrome, a rare genetic condition that affects about 1 in 13,000 people and causes compulsive overeating that is linked to obesity. The drug attempts to modify the manner in which the body metabolizes fat.
- Zafgen announced the first patient death (also from pulmonary blood clots) in October, leading the FDA to place a safety-related partial clinical hold on beloranib trials and the company to implement a more stringent screening process for trial participants. It's important to note that a direct link between the drug and the blood clots/deaths has not been incontrovertibly established—but the fact that several patients in studies involving beloranib have reported blood clots isn't encouraging.
- News of the second patient death sent Zafgen shares plummeting more than 60% in early Wednesday trading.
It's been a rough end to 2015 for Zafgen, and there's a chance that this newest patient death could permanently scuttle the firm's development program for beloranib. Industry observers are already speculating that the FDA may halt all belonarib trials in the face of the drug's ostensible safety risk (UPDATED ABOVE). That would essentially eradicate all prospects in Zafgen's current clinical-stage pipeline.
"Our thoughts are with the patient and their family at this time," said Zafgen CEO Thomas Hughes in a statement, adding that the company is in discussions with the FDA over how to proceed. "Patient safety remains our top priority, and we are investigating the circumstances around this event."