Efficacy and Safety of Phentermine/Topiramate in Youth With Hypothalamic Obesity

Hypothalamic obesity (HO) refers to the substantial weight gain that often complicates hypothalamic brain tumors. Children with this treatment-recalcitrant form of obesity have excess rates of metabolic sequelae compared to otherwise healthy children with similar obesity, and later experience excess mortality related to cardiometabolic disease. In this pilot trial, our objective is to gather key preliminary data about phentermine/topiramate (Ph/T) that is FDA-approved for "common" obesity but has never been tested in HO. The subset of individuals with HO who experience hyperphagia or excess daytime sleepiness may benefit from the Ph/T-induced decrease in appetite and increase in alertness. Preliminary assessments of safety, adverse events, dosing (Aim 1), as well as of efficacy (% BMI loss, Aim 2) will be made in a 28-week parallel-arm double-blinded Phase 2 placebo-controlled clinical trial in 6-28-year-old individuals with HO.