Abcuro disclosed that its phase 2/3 trial of ulviprubart, an anti‑KLRG1 antibody for inclusion body myositis (IBM), failed to meet the study’s primary and key secondary endpoints in a 272‑patient cohort. The program showed no statistically significant improvement on the IBM Functional Rating Scale versus placebo at Week 76, though a prespecified subgroup with milder disease exhibited signals of benefit. Abcuro said it will engage the FDA to discuss next steps; the result dampens near‑term approval prospects and underscores execution risks for immune‑modulatory strategies that selectively deplete cytotoxic T‑cell subsets.