** Shares of drugmaker Rhythm Pharmaceuticals RYTM.O rise 15.14% to $75 premarket
** Co tested its experimental drug bivamelagon in a mid-stage trial of 28 patients aged 12 years or older
** The drug showed reductions in body mass index at 14 weeks of treatment in patients with acquired hypothalamic obesity
** Co plans to seek input from U.S. and EU regulatory authorities on a late-stage trial design
** Acquired hypothalamic obesity is a rare form of obesity that occurs following damage to the hypothalamic region of the brain
** Up to last close, stock up ~16% YTD