Taltz (ixekizumab) and Zepbound (tirzepatide) - (TOGETHER-PsO)

Oct. 9, 2026: Eli Lilly and Company (NYSE: LLY) reported new exploratory biomarker data from the Phase 3b TOGETHER-PsO trial (NCT06588283) at the 2026 Fall Clinical Dermatology Conference. The study evaluates concomitant Taltz (ixekizumab) plus Zepbound (tirzepatide) versus Taltz alone in adults with moderate-to-severe plaque psoriasis and obesity or overweight with at least one weight-related comorbidity.

The prespecified analysis found broader biomarker changes with the combination than with Taltz monotherapy, seen as early as Week 12. By Week 36, the combination showed more differentially expressed proteins (482 vs. 140) and genes (467 vs. 16). Lilly said the combo also produced greater reductions in inflammatory immune activity, including neutrophil-related markers; changes in some neutrophil-associated markers mediated part of the additional PASI benefit versus Taltz alone.

The company said these findings follow previously reported TOGETHER-PsO results showing superior skin clearance and clinically meaningful weight reduction for Taltz plus Zepbound versus Taltz alone at the Week 36 primary endpoint, with improvements maintained or further improved through Week 52 and safety consistent with the known profiles of both drugs.

TOGETHER-PsO randomized 274 patients 1:1 over 52 weeks.