Lilly Reports Positive Psoriasis/Obesity Drug Trial
Eli Lilly announced that a Phase 3b trial combining its drugs Taltz (for psoriasis) and Zepbound (for obesity) met its primary endpoint. The study showed that using the two drugs together delivered superior results in skin clearance and weight loss compared to using Taltz alone.
- Taltz (ixekizumab) works by selectively targeting and blocking Interleukin-17A (IL-17A), a specific protein that plays a key role in driving the chronic inflammation associated with psoriasis. - Zepbound (tirzepatide) is a dual-action drug that mimics two natural gut hormones, GIP and GLP-1, to regulate appetite and slow the passage of food, which signals a feeling of fullness to the brain. - This drug class is a significant revenue driver for Eli Lilly; company-wide revenue grew 45% to $12.73 billion in the first quarter of 2025, largely propelled by sales of Zepbound and its diabetes counterpart, Mounjaro. - The official name of the trial is TOGETHER-PsO; it is a Phase 3b study that enrolled approximately 250 adults with moderate-to-severe plaque psoriasis and a BMI of at least 27. - The list price for a one-month supply of Zepbound is $1,086.37, while a single Taltz injection has a list price of $7,261.51, though the company offers savings programs that can lower patient costs significantly. - A similar combination trial for psoriatic arthritis, TOGETHER-PsA, showed that adding Zepbound to Taltz resulted in a 64% relative improvement in arthritis disease activity compared to using Taltz alone. - The psoriasis treatment market includes major pharmaceutical competitors like AbbVie, Pfizer, and Johnson & Johnson, with key drug classes including TNF-inhibitors and other interleukin-inhibitors. - To meet surging demand for its weight-loss drugs, Eli Lilly is heavily investing in manufacturing, with CEO David Ricks noting the company has invested $50 billion in new production facilities.
