Roche and Zealand Pharma reported Phase II results for petrelintide, an amylin analog for obesity, that produced a mean 10.7% weight reduction at 42 weeks versus 1.7% for placebo — below investor expectations for a differentiated competitor to Lilly’s GLP‑1‑centric candidates. Zealand’s shares plunged more than 30% on the news. Zealand argued the trial demonstrated favorable tolerability and a clear safety profile, supporting progression to Phase III later this year; analysts flagged the efficacy gap relative to rival agents and noted a potential ceiling effect at higher doses. William Blair and other firms said the magnitude of weight loss may limit petrelintide’s commercial positioning in an increasingly competitive market. The readout underscores how efficacy expectations set by leading candidates are reshaping development and valuation in obesity drug R&D. Sponsors will face amplified commercial and dosing strategy scrutiny when advancing candidates into late‑stage trials.