Yellow Target

Promise for a New Targeted Obesity Therapy Soon

New data from Rhythm Pharmaceuticals this week tells us that a new, highly targeted obesity therapy may become available soon. The data come from two phase 3 studies of setmelanotide in rare cases genetic obesity. With these positive results in hand, Rhythm expects to file for FDA approval in late 2019 or early 2020. Thus, this innovative drug for rare forms of obesity may be available by the end of 2020.

Small Studies, Rare Diseases

Let’s be clear. Rhythm has been very targeted in its research. They’ve studied very rare forms of obesity – leptin receptor (LEPR) and POMC deficiency. LEPR deficiency affects no more than 2,000 patients in the U.S. POMC deficiency is even rarer – no more than 500 patients. These diseases show up in young children. So, the studies focus on children between six and eleven years old.

Naturally, the studies are very small. But the results are impressive.

In POMC deficiency, 80 percent of subjects lost more than 10 percent of their starting weight. On average, the mean reduction in body weight was 25 percent.

For LEPR deficiency, the results were strong, but less impressive. The proportion achieving ten percent or greater weight loss was 45 percent. The mean reduction in body weight was 12.5 percent.

Because these are rare diseases, nearly impossible to treat, FDA has designated setmelanotide as a breakthrough therapy. Thus, the studies were done as open label studies, uncontrolled. For patients with these deficiencies, spontaneous recovery is unheard of.

A Risky Road to Important Innovation

Without a doubt, developing a drug for targeted obesity therapy in rare genetic conditions is risky. Zafgen went down a similar path with beloranib and hit a dead end in 2016.

Though orphan drugs are risky, they’re important. Here’s hoping for success with setmelanotide. This is innovation that some kids with severe obesity really need.

Click here and here for more information on the setmelanotide results.

Yellow Target, photograph © Andy Maguire / flickr

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August 9, 2019