← Research Digest
30 Oct 2026 · Tirzepatide

Adding tirzepatide to an arthritis drug in psoriatic arthritis with excess weight (TOGETHER-PsA)

Studied in
271 adults with active psoriatic arthritis and overweight or obesity
Design
Randomised, phase 3b, 52 weeks (main results at 36 weeks)
Evidence
A · Human RCT

What was studied

Most people with psoriatic arthritis, an inflammatory joint disease, also carry excess weight. All participants received the biologic ixekizumab, and half were randomly assigned to add tirzepatide, to see whether the combination controls the arthritis better.

What was found

At 36 weeks, 31.7% on the combination reached both a 50% improvement in arthritis scores (ACR50) and at least 10% weight loss, against 0.8% on ixekizumab alone. ACR50 by itself was reached by 33.5% versus 20.4%, and physical function and fatigue scores also improved more. No new safety concerns were reported.

What it doesn’t tell us

Because the main goal included 10% weight loss, a large gap was expected; the joint-only difference is the more informative figure. Both drugs are made by the same manufacturer. The trial can’t say whether the same weight loss reached another way would help the joints as much.

Source · Merola JF et al. 2026, Arthritis RheumatolPubMedDOI