Patient Death Means Uncertain Future for Zafgen Obesity Drug

Zafgen, a small biotech company “dedicated to the treatment of obesity,” is learning about the risks of their strategy of focusing on drug development for severe obesity. We’ve commented before that their focus is impressive and now it’s being tested. The pivotal randomized controlled trial (RCT) of the lead Zafgen obesity drug, beloranib, was halted after a patient with Prader-Willi syndrome died due to blood clots while taking the drug in the trial.

The latest news is that Zafgen CEO Thomas Hughes says:

We believe we have an adequate number of patients who’ve been through the trial without disruption so that we can analyze the data and assess the benefits.

It’s an unfortunate and very sad thing. But blood-clotting is something that occurs commonly in this population. We have no basis to suggest that taking beloranib triggers clots. What we’re trying to assess is whether beloranib has the ability to amplify clotting.

Zafgen Stock PriceCompleting that assessment will not be easy while armchair quarterbacks render uninformed opinions. A class-action lawsuit was filed this week on behalf of investors looking to collect some money because they feel misled and and inadequately informed by Zafgen’s disclosures about this unfolding situation. Their stock is down by 77% from where it was two months ago.

The company reports that they have enough data to allow for a meaningful analysis of the RCT data and an FDA filling if the results are good enough to support it. They also note that a majority of patients who completed the RCT have chosen to continue taking the drug in an open-label extension of the study that is ongoing.

So, we’re left with a bit of uncertainty while scientists try to figure out how much of this outcome was due to beloranib and how much was due to this difficult disease. We hope the facts will allow them to stay the course.

Click here to read more from the Boston Globe, here for more from the Wall Street Journal, and here for perspective from Seeking Alpha.

Uncertain, photograph © Peter G Trimming / flickr

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October 24, 2015

2 Responses to “Patient Death Means Uncertain Future for Zafgen Obesity Drug”

  1. November 01, 2015 at 3:59 pm, Michael said:

    Your post is not entirely accurate. There is some conflating going on…

    The trials were not halted due to the patient death. The FDA issued a partial clinical hold, which means that each patient had to undergo a more rigorous thrombosis risk assessment than had been the case at the start of the trial.

    Separately, Zafgen chose to end the randomized portion of the trial and placed everyone (who wanted to, and passed the thrombosis risk assessment) on the open label extension portion.

    The difference is significant because it (along with allowing the open label extension) speaks to the FDA’s willingness to permit Zafgen to go forward in this trial.

    • November 01, 2015 at 4:08 pm, Ted said:

      Thanks for your comment, Michael.