Gilead Sciences (GILD) is nearing the completion of two phase III studies of the Jak inhibitor momelotinib in myelofibrosis, a disease affecting bone marrow.
One of these Gilead studies compares momelotinib head-to-head against Jakafi, another Jak inhibitor and the current standard of care in myelofibrosis marketed by Incyte (INCY) and Novartis (NVS) . The second study compares Gilead's momelotinib against best alternative care in patients previously treated with Jakafi.
Results from both of Gilead's momelotinib studies are expected this quarter.
Gilead has struggled mightily to produce a successful drug from its research pipeline that isn't targeted at HIV or hepatitis C, so the outcome of the momelotinib studies are acutely important. Sales of Zydelig, Gilead's only approved blood cancer drug, have been disappointing to date and safety issues forced the company to abandon front-line combination studies earlier this year.
For Incyte, momelotinib represents the last near-term threat to its dominance of the myelofibrosis treatment market. Five years after approval, Jakafi is a blockbuster drug with 2016 sales expected to reach $852 million in the U.S. and $577 million outside the U.S., according to FactSet. [Incyte records U.S. Jakafi sales; Novartis reports ex-U.S. sales and pays a royalty to Incyte.]
By 2018, Jakafi worldwide sales are projected to exceed $2.1 billion, according to FactSet. (Jakafi sales forecasts include use in patients with polycythemia vera, a similar bone marrow disease for which it's also approved.)
Jakafi is an effective myelofibrosis drug but a lack of competition has helped. Drugs that could have potentially competed against Jakafi from Sanofi (SNY) , Celgene (CELG) , AstraZeneca (AZN) , CTI Biopharma (CTIC) and Geron (GERN) have either been discontinued due to failed studies or hit significant developmental roadblocks.
For the near term, Gilead and momelotinib remains the last viable Incyte competitor.
Myelofibrosis is a disorder in which abnormal bone marrow stem cells produce scar tissue that replaces healthy marrow. Patients with myelofibrosis suffer from enlarged spleens and anemia.