Phil Nadal

Phil Nadal asked for further details on the efficacy endpoints for the Prader-Willi Syndrome (PWS) trial, specifically what weight loss (e.g., 5% at one year) and hyperphagia changes would constitute proof of concept for Imcivree.

Answer

David Meeker, Chairman, CEO and President, Rhythm Pharmaceuticals, stated that success would be a judgment call based on patient-by-patient data from a small cohort (10-20 patients for six months), aiming for results that suggest a 5% BMI decrease in a 52-week Phase III trial. He clarified that BMI percent change is the primary endpoint, and while hyperphagia (HQCT) is collected, it's an open-label trial, making interpretation difficult without a control group. He emphasized that BMI improvement would inherently imply hyperphagia improvement given the drug's biology.

Phil Nadal inquired about the specific efficacy endpoints needed for InSibiri in Prader-Willi syndrome (PWS), particularly what constitutes success for weight loss (e.g., 5% at one year) and any interpretable hyperphagia changes.

Answer

David Meeker, Chairman, CEO and President, stated that success would be a judgment call based on patient-by-patient data from a small cohort (10-20 patients over six months), not a magic linear metric. He emphasized that BMI % change is the primary endpoint, and if achieved, hyperphagia improvement would follow due to the drug's biology. He clarified that Rhythm would not pursue a hyperphagia-only label.