By Don Tracy, Associate Editor

Approval of Niktimvo was based on positive data from the AGAVE-201 study, which demonstrated a 75% response rate in patients with chronic graft-versus-host disease.The FDA has approved Incyte Sundax Pharmaceuticals’ Niktimvo (axatilimab-csfr), an anti-CSF-1R antibody, for treating chronic graft-versus-host disease (GVHD) in patients who have not responded to at least two previous lines of systemic therapy. According to both companies, Niktimvo is the first approved anti-CSF-1R antibody targeting the drivers of inflammation and fibrosis seen in chronic GVHD. The approval was based on promising results from the AGAVE-201 study.1
“With the approval of Niktimvo, patients with chronic GVHD whose disease has progressed after prior therapies, now have a new treatment option with a novel mechanism of action to help address the serious and devastating complications associated with this disease,” said Hervé Hoppenot, CEO, Incyte, in a press release. “Niktimvo is Incyte’s second approved treatment for chronic GVHD, underscoring our continued commitment to advancing the development of new medicines on behalf of patients with this disease and the medical community.”
AGAVE-201 is a global, dose-ranging trial that evaluated the efficacy, safety, and tolerability of Niktimvo in 241 adult and pediatric patients with recurrent or refractory active chronic GVHD whose disease had progressed after two prior therapies. Study participants were randomly assigned to receive a distinct dose of Niktimvo administered at 0.3 mg/kg every two weeks, 1.0 mg/kg every two weeks, or 3.0 mg/kg every four weeks.
The primary endpoint of the study was the proportion of patients in each dose group who achieved an objective response as defined by 2014 NIH Consensus Criteria for chronic GVHD by cycle seven day one, with secondary endpoints including duration of response, percent reduction in daily steroids dose, organ specific response rates, and validated quality-of-life assessments using the modified Lee Symptom Scale.
Niktimvo demonstrated a 75% overall response rate within the first six months of treatment, with durable responses observed across multiple organs. Additionally, 60% of patients maintained a response at the one-year mark. The trial also demonstrated that 56% of all patients achieved a ≥7-point improvement in the modified Lee Symptom Scale score.1
“The approval of Niktimvo represents a significant treatment advancement for patients with chronic GVHD who have failed at least two lines of previous therapy,” said Michael A. Metzger, CEO, Syndax, in the press release. “We look forward to bringing this first-in-class anti-CSF-1R antibody to patients in need of new treatment options, while also continuing to explore axatilimab’s potential in combination with other standard of care therapies for chronic GVHD and in other indications.”
In terms of safety, serious adverse events (AEs) were reported in 44% of patients treated with Niktimvo, such as infection, viral infection, and respiratory failure. Ten percent of patients discontinued treatment as a result of serious AEs and dose reductions were required in 8% of patients. Common AEs included increased aspartate aminotransferase, infection, increased alanine aminotransferase, decreased phosphate, decreased hemoglobin, viral infection, increased gamma glutamyl transferase, musculoskeletal pain, increased lipase, fatigue, increased amylase, increased calcium, increased creatine phosphokinase, increased alkaline phosphatase, nausea, headache, diarrhea, cough, bacterial infection, pyrexia, and dyspnea.1
“Advanced chronic GVHD is characterized by the development of fibrotic tissue across multiple organ systems, including most commonly the skin and mucosa, and can be extremely difficult to treat, leading to high rates of morbidity and mortality,” said Daniel Wolff, MD, PhD., head, GVHD Center at the University Hospital Regensburg, in the press release. “I am excited that Niktimvo is designed to specifically target key drivers of inflammation and fibrosis in chronic GVHD, and I am highly encouraged by the robust responses observed across all organs and patient subgroups within the heavily pre-treated population enrolled in the AGAVE-201 trial. I look forward to having a new and differentiated treatment option for my patients who need additional therapies to address this very difficult to manage, debilitating, disease.”