Biopharmaceutical company Syndax Pharmaceuticals and Royalty Pharma have announced a $350m synthetic royalty agreement based on US net sales of Niktimvo (axatilimab-csfr).

Under the agreement, Syndax Pharmaceuticals received a $350m upfront payment in exchange for a royalty of 13.8% on the net sales of Niktimvo in the US.

Royalty payments to Royalty Pharma will end once a 2.35x multiple is reached.

Syndax Pharmaceuticals CEO Michael Metzger said: “With this significant infusion of capital, we are well positioned to successfully launch two first-in-class medicines and expand their opportunity with additional indications.

“Royalty Pharma shares our belief that Niktimvo can create significant value as a new treatment option for patients with chronic graft-versus-host disease (GVHD) and recognizes its multi-billion-dollar franchise potential.”

Niktimvo is a first-in-class anti-CSF-1R antibody approved in the US for treating chronic graft-versus-host disease (GVHD) in adults and paediatric patients who have failed at least two prior lines of systemic therapy.

In the US, Niktimvo will be co-commercialised by Syndax Pharmaceuticals and Incyte. Outside the US, Incyte holds exclusive commercialisation rights.

Syndax Pharmaceuticals plans to launch axatilimab-csfr in the US by early Q1 2025.

The biopharmaceutical company licensed the exclusive worldwide rights to develop and commercialise axatilimab from UCB in 2016.

In September 2021, Syndax Pharmaceuticals and Incyte formed a co-development and co-commercialisation agreement for axatilimab in chronic GVHD (cGVHD) and future indications.

In August, the US Food and Drug Administration (FDA) approved axatilimab-csfr for the treatment of cGVHD.

Axatilimab is also being tested in additional clinical trials for chronic GVHD. A Phase 2 trial combining axatilimab with ruxolitinib is ongoing, and a Phase 3 trial with steroids is in preparation.

The drug is also being studied in an ongoing Phase 2 trial for idiopathic pulmonary fibrosis.

Royalty Pharma founder and CEO Pablo Legorreta said: “Niktimvo is a first-in-class product that has the potential to address the serious and devastating complications associated with chronic GVHD, where there is clear unmet need for additional treatment options.

“We look forward to Syndax and their partner Incyte launching Niktimvo soon and bringing this important medicine to GVHD patients.”

Goldman Sachs & Co. served as the exclusive financial adviser, while Cooley acted as legal adviser to Syndax Pharmaceuticals. Gibson, Dunn & Crutcher and Dechert provided legal counsel to Royalty Pharma.