Novartis and Incyte Corp's ruxolitinib has impressed in a second late-stage trial for myelofibrosis and will be filed for approval in the coming months.

A 219-patient Phase III trial of ruxolitinib, a Janus kinase (JAK) inhibitor, has met its primary endpoint of significantly reducing spleen size in patients with MF when compared to best available therapy. The results from the European study confirmed positive data from US trials of the drug and will form the basis of worldwide regulatory filings, planned to begin in the second quarter, first across the Atlantic and then in the European Union.

MF is an uncommon, life-threatening blood cancer characterised by bone marrow failure and enlarged spleen (splenomegaly). Symptoms including fatigue, night sweats and pruritus, poor quality of life, weight loss and shortened survival.

Novartis noted that MF has "a poor prognosis and limited treatment options", adding that although allogeneic stem cell transplantation may cure the disease, "the procedure is associated with significant morbidity and mortality and is usually appropriate only in younger patients". The five-year survival rate after transplantation is around 50%.

Both the European Commission and the US Food and Drug Administration have granted ruxolitinib orphan drug status for MF. Complete data from the new trial will be submitted to an upcoming medical meeting.