Zura Bio said on November 9 that its Phase 2 TibuSHIELD study of tibulizumab in moderate-to-severe hidradenitis suppurativa did not meet its primary endpoint, the percentage change from baseline in total abscess and inflammatory nodule count at week 16. The global, randomised, double-blind, placebo-controlled trial enrolled 247 participants across two tibulizumab dose arms and placebo. Reductions in nodule count were 56.0 percent at 300 mg and 58.1 percent at 150 mg, against 52.5 percent on placebo, a gap too small to carry the endpoint against a high placebo response. The key secondary endpoints also missed: HiSCR50 response rates were 48.0 percent and 52.7 percent on the drug against 45.5 percent on placebo, and HiSCR75 rates were 35.3 percent and 34.0 percent against 28.1 percent.
Tibulizumab is a dual inhibitor of IL-17 and BAFF. Both doses were well tolerated, the company said, with treatment-emergent adverse events in 52.4 percent of patients on each dose against 46.3 percent on placebo. One death, a cardiac arrest in a participant with multiple cardiovascular risk factors in the 300 mg arm, was assessed by the site investigator as unrelated to treatment, and there was one adverse event of special interest, an exacerbation of pre-existing inflammatory bowel disease. Zura is discontinuing development of tibulizumab in hidradenitis suppurativa, and Endpoints reported the shares fell sharply on the readout.
The company is continuing the same antibody in two other indications, arguing that systemic sclerosis and polymyalgia rheumatica have distinct biology from hidradenitis suppurativa, a deep-tissue skin disease where biologic pharmacology is known to behave differently. Topline results from the TibuSURE trial in systemic sclerosis are expected in the first half of 2027, and the NEXUS-PMR trial in polymyalgia rheumatica is planned to start by the end of this year.