The U.S. Food and Drug Administration (FDA) has granted approval to Incyte and Syndax Pharmaceuticals for their monoclonal antibody therapy, Niktimvo (axatilimab-csfr), marking a significant advancement in the treatment of chronic graft-versus-host disease (GvHD). This approval positions Niktimvo as a third-line treatment option for both adults and children weighing at least 40 kilograms, offering new hope to patients who have exhausted other therapeutic avenues.
Niktimvo’s approval adds to Incyte’s expanding portfolio of GvHD treatments, where it joins Jakafi (ruxolitinib), a drug that generated $2.6 billion in sales last year. With the anticipated U.S. launch of Niktimvo in the first quarter of 2025, market analysts, including those from GlobalData, project that the drug could achieve over $305 million in sales by 2030. This financial outlook underscores the significant commercial potential of Niktimvo within the highly specialized field of GvHD treatment.
Niktimvo operates as a colony-stimulating factor 1 receptor (CSF1R)-targeting monoclonal antibody. This mechanism of action differentiates it from other available therapies, potentially offering a more targeted approach to managing chronic GvHD. The drug is co-marketed by Incyte and Syndax within the United States, with Incyte retaining exclusive commercialization rights outside of the U.S. This strategic partnership dates back to 2016 when Syndax acquired the worldwide rights to Niktimvo from UCB.
The FDA’s decision to approve Niktimvo was heavily influenced by the positive results from the Phase II AGAVE-201 trial (NCT04710576). This study met its primary endpoint, achieving a remarkable 75% overall response rate within six months of treatment. The median time to response was reported to be just 1.5 months, highlighting the drug’s rapid efficacy. However, it is essential to note that the trial also identified several side effects, including elevated levels of aspartate aminotransferase, blood creatine phosphokinase, lipase, blood lactate dehydrogenase, and alanine aminotransferase, all indicative of potential tissue damage. Serious adverse events were observed in 42.3% of participants, leading to the discontinuation of treatment in 37 cases.
As the market for GvHD therapies continues to evolve, multiple other treatments are under development. Pfizer’s sirolimus, a macrolide lactams derivative, and Eli Lilly’s Olumiant (baricitinib) are both undergoing Phase II trials, reflecting the ongoing interest in expanding therapeutic options for this challenging condition. Meanwhile, Equillium’s IgG1 monoclonal antibody, itolizumab, is in a Phase III trial (NCT05263999), potentially setting the stage for even more treatment options in the near future.
Mesoblast is also pursuing advancements in GvHD treatment, though its journey has been more challenging. The company is developing a cell therapy for steroid-refractory acute GvHD but has faced setbacks, with the FDA twice rejecting its therapy remestemcel-L, citing the need for additional data.
Incyte and Syndax are not resting on their laurels following Niktimvo’s approval. Incyte is currently evaluating Niktimvo as a first-line combination therapy with Jakafi in chronic GvHD through a Phase II trial (NCT06388564), which is anticipated to commence recruitment by the end of this year. Additionally, a Phase III trial investigating Niktimvo in combination with steroids for the same indication is expected to begin by the close of 2024. Syndax is also exploring the potential of Niktimvo beyond GvHD, with a Phase II trial (NCT06132256) underway to assess its efficacy in treating idiopathic pulmonary fibrosis. This trial is expected to enroll approximately 135 participants, with results anticipated by the second quarter of 2025.
Key Takeaways:
- The FDA has approved Niktimvo (axatilimab-csfr) as a third-line treatment for chronic GvHD in adults and children over 40 kg.
- Niktimvo is part of Incyte’s GvHD treatment portfolio, which includes Jakafi, a drug that generated $2.6 billion in sales in the previous year.
- The Phase II AGAVE-201 trial, which led to the FDA approval, reported a 75% overall response rate with a median time to response of 1.5 months.
- The global market for GvHD treatments remains competitive, with multiple therapies from Pfizer, Eli Lilly, and others currently in development.
- Incyte and Syndax are further investigating Niktimvo for other indications, including as a first-line combination treatment for chronic GvHD and idiopathic pulmonary fibrosis.
Conclusion:
The FDA’s approval of Niktimvo marks a critical milestone for Incyte and Syndax in the competitive GvHD treatment landscape. With strong clinical trial results and a promising commercial outlook, Niktimvo is poised to become a significant player in the market. As the companies continue to explore additional applications for the drug, including its potential in other serious conditions, Niktimvo’s success may herald further innovations in the treatment of chronic GvHD and beyond.
