Lilly's Taltz and Zepbound Show Superior Results in Psoriatic Arthritis and Obesity Trial

Key highlights
  • The TOGETHER-PsA study met its primary endpoint at 36 weeks with Taltz and Zepbound showing a 50% improvement in PsA activity and ≥10% weight reduction.
  • Taltz plus Zepbound delivered a 64% relative increase in ACR50 achievement compared to Taltz alone, with 33.5% vs. 20.4% of patients responding.
  • The study included patients with an average BMI of 37.6 kg/m² and high disease burden, with over 60% having prior advanced therapy experience.
  • Adverse events were mild to moderate, with common issues being nausea, diarrhea, constipation, and injection site reactions.

Study Overview

The TOGETHER-PsA Phase 3b trial evaluated the combined use of Taltz (ixekizumab) and Zepbound (tirzepatide) against Taltz alone in adults with active psoriatic arthritis (PsA) and obesity or overweight. At 36 weeks, the study met its primary endpoint, showing a 50% improvement in PsA activity and a weight reduction of at least 10% with the combined treatment.

Key Findings

The combination of Taltz and Zepbound resulted in a 64% relative increase in the proportion of patients achieving ACR50 compared to Taltz alone, with 33.5% versus 20.4% of patients responding. The study population had a high disease burden, with an average BMI of 37.6 kg/m², and over 60% had prior experience with advanced therapies.

Adverse Events

Adverse events in the trial were generally mild to moderate. Common issues in the Taltz and Zepbound group included nausea, diarrhea, constipation, and injection site reactions. In the Taltz monotherapy group, injection site reactions and upper respiratory tract infections were most common.

Implications

This trial is the first controlled study to evaluate an incretin therapy with a PsA biologic, highlighting the potential for integrated treatment approaches. The findings suggest that treating obesity can improve PsA disease measures, offering a new paradigm for managing patients with both conditions.

Source: Lilly

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