Positive topline results from the AGAVE-201 trial of axatilimab

On July 24, 2023, positive topline results were announced from the AGAVE-201 trial of axatilimab, an investigational anti-colony-stimulating factor 1 receptor (CSF-1R) antibody, which was granted orphan drug designation by the U.S. Food and Drug Administration (FDA) in 2021. Results from a phase I/II trial of axatilimab in patients with chronic graft-versus-host disease (cGvHD) have been previously reported by the GvHD Hub, it has also shown macrophage reduction in pre-clinical models.

AGAVE-201, a phase II dose-escalation study, enrolled 241 pediatric and adult patients with refractory or recurrent cGvHD who have experienced disease progression after two previous lines of therapy. Across all three dosing cohorts (0.3 mg/kg every 2 weeks, 1 mg/kg every 2 weeks, and 3 mg/kg every 4 weeks), the primary endpoint of objective response by Cycle 7 Day 1 was achieved, with 74%, 67%, and 50% of patients achieving an overall response within the first 6 months, respectively.

Common adverse events were fatigue and increased aspartate aminotransferase, blood creatine phosphokinase, lipase, blood lactate dehydrogenase, and alanine aminotransferase. Overall, 42.3% of patients experienced a serious adverse event, with 15.5% of patients discontinuing the study due to adverse events.

It is predicted that a Biologic License Application for axatilimab will be filed later this year, with a phase III trial expected to follow.