Lilly’s Taltz and Zepbound Show One-Year Benefits

Indianapolis, Indiana, August 31, 2026

Phase 3b Study Evaluates Combined Treatment

The new findings come from a Phase 3b clinical program evaluating adults with psoriatic disease and obesity who received Taltz and Zepbound together. The study examined outcomes over a one-year period, providing an opportunity to assess whether improvements associated with the individual therapies could be maintained during longer-term treatment. Taltz (ixekizumab) is an interleukin-17A (IL-17A) inhibitor used to treat several inflammatory conditions, including plaque psoriasis and psoriatic arthritis. By selectively targeting IL-17A, ixekizumab is designed to reduce inflammatory signaling involved in the development of psoriatic disease. Zepbound (tirzepatide) is a once-weekly medicine that activates both glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptors and is used for chronic weight management in eligible adults. The combination therefore brings together two therapies with different biological mechanisms and treatment objectives. Taltz targets inflammatory pathways associated with psoriatic disease, while Zepbound addresses metabolic pathways involved in appetite regulation, food intake and body-weight control. The Phase 3b findings are relevant because obesity and psoriatic disease can coexist and may create additional challenges for patients and healthcare professionals managing long-term treatment.

Durable Efficacy Reported at One Year

According to Lilly, participants receiving the combination demonstrated improved and durable efficacy through one year of treatment. The findings support the potential for sustained clinical benefits when both therapies are used together in adults affected by psoriatic disease and obesity. Psoriatic disease encompasses conditions such as plaque psoriasis and psoriatic arthritis, which can involve persistent inflammation and substantially affect patients’ physical functioning and quality of life. Obesity is also frequently observed among people with psoriatic disease, creating a clinically relevant overlap between inflammatory and metabolic health. The one-year data are particularly important because durable treatment effects are a key consideration in chronic diseases that require long-term management. Maintaining control of psoriatic disease while achieving and sustaining weight-management outcomes may help address multiple health needs within a patient population carrying both conditions. The results also contribute to growing clinical interest in understanding how obesity treatment and immunological disease management may interact when therapies are administered concurrently. However, the reported findings should be interpreted within the specific population and study design evaluated in the Phase 3b program.

Lilly Advances Integrated Treatment Research

The new Phase 3b results expand Lilly’s clinical development work involving Taltz and Zepbound, two medicines with established roles in inflammatory and metabolic disease treatment. The data may help inform future research into treatment approaches for patients who require management of both psoriatic disease and obesity. Taltz’s targeted IL-17A inhibition and Zepbound’s dual GIP/GLP-1 receptor agonism represent distinct pharmacological approaches. Studying the therapies together provides an opportunity to evaluate clinical outcomes when inflammatory disease control and weight management are addressed simultaneously rather than independently. The one-year findings reinforce the importance of long-term efficacy and treatment durability when evaluating therapies for chronic diseases. Further analyses and continued clinical research will be important for understanding the full implications of combined treatment, including its safety profile, patient-reported outcomes and potential effects across different manifestations of psoriatic disease. For Lilly, the results represent another milestone in exploring how its medicines can address interconnected areas of immunology and metabolic health. The findings may ultimately contribute to a broader understanding of treatment strategies for adults living with both psoriatic disease and obesity, while additional evidence will be needed to determine the clinical role of concurrent Taltz and Zepbound therapy.

Source: Eli Lilly press relese