Dr Kuykendall on the FDA Approval of Momelotinib in Myelofibrosis

Andrew Kuykendall, MD, assistant member, Department of Malignant Hematology, Moffitt Cancer Center, discusses the significance of the FDA approval of momelotinib (Ojjaara) in patients with myelofibrosis with anemia.

On September 15, 2023, the FDA approved momelotinib for adult patients with intermediate- or high-risk myelofibrosis, including primary or secondary myelofibrosis, with anemia, based on findings from the phase 3 MOMENTUM (NCT04173494) and SIMPLIFY-I (NCT01969838) trials. In this study, momelotinib elicited a tumor symptom score reduction of at least 50% at week 24 in 25% of patients with symptomatic and anemic myelofibrosis with prior JAK inhibitor exposure vs 9% of patients who received danazol in the control arm (P = .0095). Momelotinib also improved spleen size and anemia in this population.

This FDA approval represents further advancement in the myelofibrosis treatment landscape, which has been expanding over the past decade, Kuykendall says. Ruxolitinib (Jakafi), which was approved by the FDA in 2011 for patients with intermediate/high-risk myelofibrosis, is associated with improvements in splenomegaly and disease-related symptoms, Kuykendall states. The agent produced a modest overall survival benefit vs placebo or best available therapy in the pivotal phase 3 COMFORT-I (NCT00952289) and COMFORT-II (NCT00934544) trials, respectively, Kuykendall explains. However, Kuykendall notes that most patients with myelofibrosis experience anemia and low platelet counts, and ruxolitinib does not offer these patients the full benefits of JAK inhibition.

In 2022, the FDA granted accelerated approval to pacritinib (Vonjo) for patients with intermediate- or high-risk myelofibrosis with severe thrombocytopenia. Now, the approval of momelotinib means that patients with myelofibrosis and anemia can receive a full dose of a JAK inhibitor that may improve anemia, Kuykendall emphasizes. This agent may also be effective in patients with low platelet counts, since MOMENTUM enrolled patients with platelet counts as low as 25 x 10⁹/L, according to Kuykendall.

The approval of momelotinib extends the benefits of JAK inhibitors to more patients with myelofibrosis and adds an agent that may help alleviate anemia to the armamentarium for these patients, Kuykendall concludes.