Eli Lilly Says Zepbound Outperforms Wegovy HD on Weight Loss in Indirect Analysis

Eli Lilly (LLY) said on September 29, 2026, that Zepbound 10 mg and 15 mg produced greater weight loss than Wegovy HD (semaglutide 7.2 mg) in a new indirect treatment comparison in adults with obesity, comparing the SURMOUNT-1 trial against the STEP UP program. At 72 weeks, Zepbound 15 mg yielded an average 4.5% greater body weight reduction under the treatment-regimen analysis; the efficacy analysis showed a 1.8% difference that was not statistically significant. Patients on Zepbound 15 mg had more than triple the odds of achieving at least 20% weight loss versus Wegovy HD. Lilly cautioned the comparison was indirect and results varied by statistical method. The company also cited SURMOUNT-5, in which Zepbound 10 mg and 15 mg beat Wegovy 1.7 mg and 2.4 mg. LLY closed Monday at $1,184.78, up 0.11%; premarket trading showed $1,186.35, up 0.03%.