Myelofibrosis is an uncommon form of blood cancer that can cause an enlarged spleen; constitutional symptoms such as night sweats, fever and weight loss; and scarring in the bone marrow. The bone marrow scarring also leads to severe anemia, which can cause fatigue and weakness.
Blood transplants and bone marrow transplants are among the few options available for treating this condition. Compounds such as ruxolitinib and danazol can be used to treat myelofibrosis but are unable to tackle anemia.
GSK’s Ojjaara is a blocker of the proteins Janus kinase (JAK) 1 and 2 as well as activin A receptor, type I (ACVR1). Given once a day, the drug is designed to combat anaemia, constitutional symptoms and splenomegaly simultaneously.
The FDA initially delayed its approval decision of Ojjaara by three months in June 2023 as the regulator wanted more time to process recently submitted data from GSK. The eventual approval was based on data from the phase 3 MOMENTUM study, where Ojjaara significantly improved constitutional symptoms, splenic response and transfusion independence in patients with myelofibrosis and anemia compared with danazol.
GSK also submitted data from another phase 3 trial called SIMPLIFY-1 where Ojjaara showed benefits compared with ruxolitinib in a subgroup of myelofibrosis patients with anemia. The most common adverse effects in the two trials included thrombocytopaenia, haemorrhage, bacterial infection, fatigue, dizziness, diarrhoea, and nausea.
“The vast majority of myelofibrosis patients eventually develop anaemia, causing them to discontinue treatments and require transfusions,” said Nina Mojas, GSK’s senior vice president, oncology global product strategy, in a public statement. “Given this high unmet need, we are proud to add Ojjaara to our oncology portfolio and address a significant medical need in the community. We look forward to helping improve outcomes in this difficult-to-treat blood cancer.”