Adding Zepbound to Taltz sustains improved psoriasis and PsA outcomes

Clinical takeaway: In patients with psoriasis or psoriatic arthritis and obesity, adding tirzepatide to ixekizumab may improve long-term disease control and metabolic health compared with biologic therapy alone, highlighting the potential value of treating immunologic and metabolic disease simultaneously.

Psoriasis and psoriatic arthritis frequently coexist with obesity, a combination linked to higher inflammatory burden and poorer treatment outcomes. New 52-week findings from the phase 3b TOGETHER-PsO and TOGETHER-PsA trials suggest that addressing both conditions concurrently may produce more durable benefits than treating psoriatic disease alone.

In the studies, patients receiving Taltz (ixekizumab) plus Zepbound (tirzepatide) maintained or further improved the advantages previously observed at 36 weeks compared with Taltz monotherapy. Among patients with psoriasis, combination therapy was associated with higher rates of complete skin clearance at one year. In psoriatic arthritis, more patients achieved meaningful improvements in joint disease activity, with benefits emerging early and persisting through week 52.

The combination also produced sustained improvements in systemic inflammation and metabolic health, including body weight, blood pressure, glycemic measures, and lipid parameters. These findings support the concept that metabolic dysfunction may contribute to disease burden in psoriatic disease and that targeting both pathways can yield complementary benefits.

No new safety concerns were identified over one year, and adverse events were generally consistent with the known safety profiles of the individual therapies, with gastrointestinal events among the most commonly reported.

The results suggest that treating psoriatic disease and obesity simultaneously may improve skin, joint, and metabolic outcomes, supporting a more comprehensive approach to care.

"These findings show what may be possible when treating psoriatic disease and obesity concurrently," said Joseph F. Merola, MD, MMSc, dermatologist, rheumatologist, and president of the Rheumatology-Dermatology Society.

Source: Eli Lilly and Company. (2026 Aug 31). New Phase 3b data on Lilly's Taltz (ixekizumab) and Zepbound (tirzepatide) used together showed improved and durable efficacy at one year in adults with psoriatic disease and obesity