Y Combinator S26 startup RonanRX is launching a telehealth platform that provides personalized dosing for GLP-1 weight-loss drugs and peptides through an integrated compounding pharmacy and management services organization. The company differentiates itself by manufacturing its own products in-house and utilizing advanced patient feedback loops for precise dose adjustments. This approach allows RonanRX to compete in a rapidly growing market currently crowded with gray-market suppliers and standard telehealth prescribers.