New York-based biopharma Syndax Pharmaceuticals (Nasdaq: SNDX) revealed that axatilimab did not acheive the primary endpoint in the Phase II MAXPIRe trial in idiopathic pulmonary fibrosis (IPF). Consequently, the company does not plan to move forward with further development of the drug in IPF.
The MAXPIRe trial was a 26-week, randomized, double-blind, placebo-controlled, multicenter Phase II study enrolling 145 patients with IPF across 62 sites in 14 countries; patients were randomized 2:1 to axatilimab 0.3 mg/kg or placebo every two weeks, with stratification by background antifibrotic therapy use. The primary endpoint was the annualized rate of decline in forced vital capacity (FVC), derived from measurements collected over the 26-week period. Syndax did not disclose numerical treatment-effect data, FVC decline rates, a p-value, or confidence interval, so the magnitude of the result cannot be assessed from the available information.
Axatilimab was well tolerated in the trial, with a safety and tolerability profile described as comparable to placebo and no new safety signals. Rates of treatment-emergent adverse events leading to discontinuation were low in both arms, and there were no treatment-related fatal adverse events in either arm.
Axatilimab is a monoclonal antibody targeting colony-stimulating factor-1 receptor (CSF-1R), which regulates monocyte and macrophage activity implicated in inflammatory and fibrotic processes. The IPF program formed part of a 2021 co-development and co-commercialization agreement between Syndax and Incyte (Nasdaq: INCY), under which Syndax agreed to fund initial IPF development while Incyte retained an option to co-fund late-stage development in the indication.