Pharmaceutical company Eli Lilly and Company (NYSE:LLY) on Saturday reported results from the TOGETHER-PsA open-label Phase 3b clinical trial evaluating the concomitant use of Taltz (ixekizumab) and Zepbound (tirzepatide) compared to Taltz alone in adults with active psoriatic arthritis (PsA) and obesity or overweight with at least one additional weight-related comorbid condition.

These results were presented in a late-breaking presentation at the 2026 American Academy of Dermatology (AAD) Annual Meeting and simultaneously published in Arthritis & Rheumatology.

According to Lilly, at the primary endpoint of 36 weeks, treatment with concomitant Taltz and Zepbound met the primary and all key secondary endpoints for statistically significant superiority to Taltz monotherapy. A greater reduction in PsA disease activity (ACR50) was seen as early as Week 4 in the Taltz and Zepbound treatment arm (as compared to Taltz alone), before clinically meaningful weight loss was observed. Treatment with Taltz and Zepbound also led to a significant increase in patients achieving Minimal Disease Activity (MDA), a high bar for PsA treatment success, along with improvements in fatigue, physical function, mental health-related quality of life, cardiometabolic health and inflammation.

In addition, Taltz plus Zepbound was associated with nominally statistically significant improvements in BMI, body weight, systolic blood pressure, glucose, HbA1c, triglycerides, and total cholesterol versus Taltz monotherapy.