Axatilimab + ruxolitinib for ND cGvHD: Updated safety results from a phase II trial

At the European Hematology Association (EHA) 2026 Congress, June 11–14, 2026, Stockholm, SE, Robert Zeiser presented updated safety data from an ongoing, randomized, phase II study (NCT06388564) evaluating axatilimab + ruxolitinib (n = 23) vs ruxolitinib (n = 24) or corticosteroids (n = 19) in patients aged ≥12 years with newly diagnosed (ND) moderate/severe chronic graft-versus-host disease (cGvHD). Patients were randomized 1:1:1 to receive axatilimab 0.3 mg/kg every 2 weeks (Q2W) + ruxolitinib 10 mg twice daily (BID), ruxolitinib 10 mg BID only, or corticosteroids only (starting dose: 1 mg/kg/day prednisone equivalent). The primary endpoint was overall response rate (ORR) at 6 months without new systemic cGvHD therapy; secondary endpoints included safety and tolerability.

Key data: The ORR at 6 months was not reported in this updated safety analysis. At data cutoff, treatment was ongoing in 73.9%, 58.3%, and 31.6% of patients receiving axatilimab + ruxolitinib, ruxolitinib, and corticosteroids, respectively. Any-grade treatment-emergent adverse events (TEAEs) occurred in 75.0%, 84.2%, and 81.3% of patients receiving axatilimab + ruxolitinib, ruxolitinib only, and corticosteroids only, respectively; corresponding rates of Grade ≥3 TEAEs were 25.0%, 15.8%, and 18.8%, while serious TEAEs occurred in 15.0%, 21.1%, and 18.8% of patients, respectively. Anemia was the only Grade ≥3 TEAE that occurred in ≥2 patients overall. Treatment discontinuation was more frequent with corticosteroids (47.4%) than with ruxolitinib (25.0%) or axatilimab + ruxolitinib (17.4%). No arm met the prespecified stopping criterion for unacceptable toxicity.

Key learning: Axatilimab + ruxolitinib demonstrated a manageable safety profile without any new safety signals or evidence of additive toxicity in patients with ND moderate/severe cGvHD.