GSK's Omjjara Receives Green Light In Japan To Combat Myelofibrosis

GSK plc (LSE/NYSE: GSK) announced today that Japan's Ministry of Health, Labour and Welfare (MHLW) has granted approval for Omjjara (momelotinib) to treat myelofibrosis. Omjjara, an oral inhibitor targeting JAK1/JAK2 and activin A receptor type 1 (ACVR1), is taken once daily. The approval is supported by data from the pivotal phase III MOMENTUM and SIMPLIFY-1 trials.This marks the fourth significant regulatory approval for GSK's momelotinib in myelofibrosis treatment. Previously, it received approval as Ojjaara from the US Food and Drug Administration, and as Omjjara from the European Commission and the UK's Medicines and Healthcare products Regulatory Agency.

 “Myelofibrosis has a heavy disease burden, with symptomatic patients experiencing spleen enlargement, fatigue, night sweats and bone pain, along with anaemia which can lead to treatment discontinuation and dependence on regular blood transfusions. With the approval of Omjjara, myelofibrosis patients in Japan will have a new treatment option for this complex blood cancer,” said Nina Mojas, Senior Vice President, Oncology Global Product Strategy, GSK. Myelofibrosis is a rare form of blood cancer affecting approximately 1 in 500,000 people globally, with an estimated 5,000 patients impacted in Japan. In Japan, around 70% of patients diagnosed with primary myelofibrosis and about half of those with secondary myelofibrosis experience moderate to severe anaemia at diagnosis.

 Almost all patients are expected to develop anaemia as the disease progresses. Those with myelofibrosis-related anaemia require additional supportive treatments such as transfusions. More than 30% of patients discontinue existing therapies due to anaemia. Individuals who are anaemic and dependent on transfusions face a challenging prognosis with reduced survival rates.

 The approval was granted based on findings from the pivotal phase III trials MOMENTUM and SIMPLIFY-1. MOMENTUM assessed momelotinib's safety and effectiveness compared to danazol in treating and reducing significant symptoms of myelofibrosis in a population experienced with JAK inhibitors and experiencing anaemia. SIMPLIFY-1 evaluated how effective and safe momelotinib is compared to ruxolitinib in myelofibrosis patients who had not previously received JAK inhibitor therapy.