The Food and Drug Administration (FDA) has granted Orphan Drug designation to setmelanotide (Rhythm Pharmaceuticals) for the treatment of Alström Syndrome.

Alström Syndrome is a rare genetic disorder that affects multiple organ systems. It is caused by genetic variants in the ALMS1 gene, which disrupts signals in the melanocortin-4 receptor pathway. The disorder may be associated with hyperphagia and severe obesity; clinical features can include progressive visual and auditory impairments, insulin resistance and type 2 diabetes, hyperlipidemia, progressive kidney dysfunction, cardiomyopathy and short stature in adulthood. 

Setmelanotide works by activating the melanocortin-4 receptor to regulate energy expenditure and appetite. The Company is currently evaluating the efficacy and safety of setmelanotide for the treatment of obesity and hyperphagia in an ongoing pivotal phase 3 trial in patients with Bardet Biedl syndrome (BBS) or Alström syndrome. 

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“Orphan drug designation from the FDA reinforces the urgency of our work with setmelanotide in Alström syndrome, as we advance our pivotal phase 3 trial to topline data expected by the end of this year or early next year,” said Murray Stewart, MD, Chief Medical Officer of Rhythm. 

Orphan Drug designation is granted to investigational treatments intended to treat or prevent rare diseases or conditions that affect fewer than 200,000 individuals in the US. 

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