Lilly reports one-year data on Taltz and Zepbound combination

One-year outcomes

In the 52-week Phase 3b TOGETHER-PsA study, 43.7% of adults receiving Taltz (ixekizumab) with Zepbound (tirzepatide) achieved ACR50, a reduction of at least 50% in psoriatic arthritis disease activity, compared with 15.7% receiving Taltz alone. The combined endpoint of ACR50 and at least 10% weight reduction was reached by 39.2% and 1.7%, respectively. At least 10% weight reduction alone was achieved by 85.7% in the combination arm and 6.7% with Taltz alone.

Patient-reported physical function and fatigue outcomes were maintained or further improved from Week 36 to Week 52 in the combination arm. The treatment was also associated with improvements in BMI, body weight, systolic blood pressure, glucose, HbA1c, triglycerides and total cholesterol versus Taltz alone. The Week 52 analyses were pre-specified exploratory objectives without multiplicity control; comparisons between timepoints were descriptive.

Study and safety

The randomized, assessor-blinded, open-label trial assigned 271 adults with active psoriatic arthritis and obesity or overweight, plus at least one weight-related comorbidity, to Taltz alone or Taltz with Zepbound. Both groups received diet and physical-activity counseling. The primary endpoint assessed at Week 36 was the proportion achieving ACR50 and at least 10% weight reduction; the study had previously reported statistically superior results for the combination on its primary and key secondary endpoints.

Adverse events with the combination were generally mild to moderate and consistent with the known safety profiles of the medicines. The 52-week results were presented at ACR Convergence 2026 and published in Arthritis & Rheumatology.