Syndax Pharmaceuticals (SNDX) FDA Announcement summary

Introduction and purpose

• FDA approved Niktimvo (axatilimab/axatilimab-csfr), the first-in-class and only anti-CSF1R therapy, for chronic GVHD after failure of at least two prior systemic therapies in adults and pediatric patients weighing at least 40kg.

• Niktimvo addresses inflammation and fibrosis in refractory cGVHD, representing a significant breakthrough for patients with high unmet medical need.

• Chronic GVHD affects about 17,000 U.S. patients, with nearly half requiring at least three lines of treatment.

• The approval marks a milestone for patients and the company’s transition to a commercial-stage entity.

Details of approval or decision

• Niktimvo is indicated for adult and pediatric patients (≥40 kg) with cGVHD after failure of at least two prior systemic therapies; the approved dose is 0.3mg/kg (max 35mg) every two weeks via IV infusion over 30 minutes.

• FDA approval was based on the pivotal AGAVE-201 trial, a multicenter, open-label study enrolling heavily pretreated patients with active cGVHD.

• Niktimvo received priority review and orphan drug designation.

• Initial commercial vial size is 50mg, with 9mg and 22mg vials expected to launch in late 2024 or early 2025.

Impact on industry and stakeholders

• Niktimvo provides a novel treatment option for advanced, refractory cGVHD, targeting an addressable U.S. third-line market estimated at $1.5–2 billion.

• Incyte and Syndax will co-commercialize Niktimvo in the U.S., with Incyte leading 70% of sales effort and both companies sharing profits equally.

• Launch strategy targets the 6,500 U.S. cGVHD patients progressing to later lines, with plans for label and geographic expansion.

• Broad payer coverage and patient support programs, including financial assistance, are planned.