FDA Approves Axatilimab 9 mg and 22 mg Vial Sizes for Chronic GVHD

Credit: US Food and Drug Administration

The US Food and Drug Administration (FDA) has approved axatilimab-csfr (Niktimvo) in 9 mg and 22 mg vial sizes, following its initial approval in August 2024 for the treatment of graft-versus-host disease (GVHD) after failure of ≥2 prior lines of systemic therapy in adult and pediatric patients weighing ≥40 kg.¹

Announced by Incyte and Syndax Pharmaceuticals on January 15, 2025, axatilimab is the first and only FDA-approved therapy for chronic GVHD that targets CSF-1R to determine drivers of inflammation and fibrosis in GVHD. According to both companies, these vial sizes are expected to be available for order in the US in early February.¹

“We are thrilled to build on our strong commitment to the GVHD community with the US launch of [axatilimab], a first-in-class therapeutic agent that has demonstrated remarkable responses in patients with chronic GVHD whose response was suboptimal after ≥2 prior lines of systemic therapy,” Hervé Hoppenot, chief executive officer of Incyte, said in a statement.¹ “Our deep understanding of chronic GVHD and our connections in the clinical community will support a successful launch, in partnership with Syndax, of this important medicine for patients.”

Chronic GVHD can follow an allogeneic stem cell transplant wherein the donated cells trigger an immune response and target the transplant recipient’s organs. Estimates suggest nearly 42% of transplant recipients will develop chronic GVHD, representing approximately 17,000 people in the US. Almost half of individuals with the condition require ≥3 lines of treatment.²

FDA approval for axatilimab in a 50mg vial was awarded in August 2024, based on positive data from the global dose-ranging AGAVE-201 trial. AGAVE-201 measured the efficacy, safety, and tolerability of axatilimab in 241 adults and children with recurrent or refractory active chronic GVHD, who experienced disease progression after ≥2 prior therapies. The population was randomized to 1 of 3 treatment cohorts, with axatilimab dosed at 0.3 mg/kg every 2 weeks, 1.0 mg/kg every 2 weeks, or 3.0 mg/kg every 4 weeks.³

Analyses showed the trial met its primary endpoint across all cohorts in the proportion of patients who achieved an objective response by cycle 7 day 1, as established by the 2014 NIH Consensus Criteria for chronic GVHD. Approximately 75% of patients receiving the 0.3 mg/kg dose every 2 weeks achieved an overall response at 6 months of axatilimab treatment (n = 79).¹

Among those who received treatment response, trial results showed no death or initiation of new systemic therapy in approximately 60% of patients for ≥12 months since response. Safety data revealed serious adverse events (SAEs) occurred in 44% of patients who received axatilimab, with permanent discontinuation in 10% and dose reduction due to adverse events in 8% of patients.³

The most common (≥15%) adverse reactions linked to axatilimab included increases in aspartate aminotransferase (AST), infection, alanine aminotransferase (ALT), gamma-glutamyl transferase (GGT), calcium, creatine phosphokinase (CPK), lipase, alkaline phosphatase (ALP), and amylase, with decreases in phosphate and hemoglobin.¹

The approved dose of axatilimab for adults and children weighing ≥40 kg is 0.3 mg/kg, up to a maximum dose of 35 mg, given as an intravenous infusion over 30 minutes every 2 weeks. Incyte and Syndax announced axatilimab will be available for healthcare providers to order thorough specialty distribution in both 9 mg and 22 mg vial sizes to enable patient dosing.¹

“As the first and only FDA-approved anti-CSF-1R antibody targeting the drivers of inflammation and fibrosis in chronic GVHD, [axatilimab] represents as major breakthrough for patient care,” Michael Metzger, chief executive officer of Syndax, said in a statement.¹ “Together with Incyte, we look forward to executing a robust commercial launch and advancing the treatment paradigm for patients with chronic GVHD who have progressed after ≥2 lines of systemic therapy.”

References

1. _{Incyte and Syndax announce U.S. Food and Drug Administration (FDA) approval of NiktimvoTM (Axatilimab-CSFR) 9 mg and 22 mg vial sizes. Syndax Pharmaceuticals, Inc. January 15, 2025. Accessed January 16, 2025. https://ir.syndax.com/news-releases/news-release-details/incyte-and-syndax-announce-us-food-and-drug-administration-fda.}
2. _{Justiz Vaillant AA, Modi P, Mohammadi O. Graft-Versus-Host Disease. [Updated 2024 Jun 7]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK538235/}
3. _{Iapoce C. FDA approves Axatilimab for chronic graft-versus-host disease. HCP Live. August 15, 2024. Accessed January 16, 2025. https://www.hcplive.com/view/fda-approves-axatilimab-for-chronic-graft-versus-host-disease.}