Metsera Inc. $MTSR, a biotech startup targeting obesity, saw a sharp rally in its stock after releasing positive early-stage trial data for its experimental weight-loss therapy, MET-233i. According to the company, the injectable drug enabled patients to lose up to 8.4% of their body weight within just 36 days during a Phase 1 study — surpassing preliminary expectations. Beyond efficacy, the treatment demonstrated prolonged bioavailability, allowing for a potentially game-changing shift from weekly to monthly administration. That differentiator, if validated in later-stage trials, could directly challenge the current market dominance of weekly injectables such as Wegovy by Novo Nordisk A/S $NVO and Zepbound by Eli Lilly & Co. $LLY.