GSK announced that the European Medicines Agency (EMA) validated the marketing authorisation application (MAA) for momelotinib, a potential new oral treatment for myelofibrosis. Momelotinib has a differentiated mechanism of action, with inhibitory ability along three key signalling pathways: Janus kinase (JAK) 1, and JAK2 and activin A receptor type I (ACVR1), which could address the significant medical needs of myelofibrosis patients with anaemia.

The MAA is based on results from key phase III trials, including the pivotal MOMENTUM trial, which met all primary and key secondary endpoints, including Total Symptom Score (TSS), Transfusion Independence (TI) rate and Splenic Response Rate (SRR). The primary analysis data from the MOMENTUM phase III trial were presented at the 2022 American Society of Clinical Oncology Annual Meeting and the European Hematology Association 2022 Hybrid Congress. Updated 48-week data will be presented at the upcoming American Society of Hematology (ASH) Annual Meeting and Exposition on 10-13 December 2022.

A Committee for Medicinal Products for Human Use (CHMP) regulatory action is anticipated by year-end 2023, and a New Drug Application for momelotinib is currently under regulatory review with the US Food and Drug Administration (FDA) with a Prescription Drug User Fee Act action date of 16 June 2023. Momelotinib is not currently approved in any market, but if approved by regulators, momelotinib would be the only medicine that addresses key manifestations of myelofibrosis, including anaemia, symptoms, and splenomegaly.

MOMENTUM is a global, randomised, double-blind phase III clinical trial of momelotinib versus danazol in patients with myelofibrosis who were symptomatic and anaemic and had been previously treated with a US FDA-approved JAK inhibitor.

The trial was designed to evaluate the safety and efficacy of momelotinib for treating and reducing key hallmarks of the disease: symptoms, blood transfusions (due to anaemia) and splenomegaly (enlarged spleen).