Eli Lilly and Company (NYSE:LLY) today announced positive topline results from its Phase 3b TOGETHER-PsO trial, demonstrating that treating psoriasis and obesity simultaneously yields significantly better outcomes than addressing skin disease alone.
The 36-week trial evaluated the concomitant use of Taltz (ixekizumab) and Zepbound (tirzepatide) in adults with moderate-to-severe plaque psoriasis and a mean BMI exceeding 39 kg/m².
The study met its primary endpoint with a striking margin: 27.1% of participants on the combination therapy reached both complete skin clearance (PASI 100) and at least 10% weight loss, compared to just 5.8% of those treated with Taltz alone.
Beyond weight loss, the data suggests that Zepbound may actually enhance Taltz’s efficacy in clearing skin.
In a key secondary endpoint, 40.6% of patients in the combination arm achieved PASI 100, representing a 40% relative increase over the 29.0% success rate seen in the Taltz monotherapy group (p< 0.05).
The safety profile of the dual-treatment approach was consistent with the known effects of each individual drug.
The most common adverse events included nausea, diarrhea, and injection site reactions, most of which were mild to moderate in severity.
The success of TOGETHER-PsO follows a similar "win" for Lilly in its TOGETHER-PsA trial (focused on psoriatic arthritis) earlier this year.
Together, these studies position Lilly as a leader in "integrated therapy," leveraging its dominant position in both the immunology and weight-loss markets.
The company plans to present detailed data at upcoming medical congresses and submit the findings to global regulatory authorities later this year.