Mixed results for Gilead slow momentum
- Gilead Sciences has presented some rather mixed topline results from two Phase 3 studies of momelotinib in patients with myelofibrosis. The company plans to discuss the results with the regulatory authorities to determine the next steps.
- In SIMPLIFY 1, momelotinib reached its primary endpoint of non-inferiority to Incyte's Jakafi (ruxolitinib), as measured by the number of patients with a 35% reduction in spleen volume at week 24 (SRR24; momelotinib 26.5%, Jakafi 29.0%). The study failed to show non-inferiority in total symptom score, the secondary endpoint, and 10% of the momelotinib patients reported peripheral neuropathy, compared with 5% in Jakafi-treated patients.
- In the SIMPLIFY 2 study, momelotinib didn't reach the primary endpoint of superiority compared with best available therapy in patients previously treated with Jakafi measured by SRR24 (6.7% vs 5.8%), though the results were similar; this is perhaps not surprising as 88% of the patients remained on Jakafi.
Gilead managed both hits and misses for its JAK inhibitor momelotinib in the SIMPLIFY 1 and 2 studies in myelofibrosis. "The results from both the SIMPLIFY-1 and SIMPLIFY-2 studies indicate that momelotinib provides some treatment benefit, including benefit on anemia-related endpoints," said CSO Norbert Bischofberger, somewhat optimistically.
Gilead has been struggling a bit this year. It ditched a Phase 2/3 study for GS-5745 in ulcerative colitis based on lack of benefit, though other indications are ongoing. Selonsertib missed the primary endpoint in Phase 2 trials for pulmonary arterial hypertension and diabetic kidney disease, pushing the company to nix these indications, though development is ongoing for non-alcoholic steatohepatitis after positive results in a small group of patients.
It's also been facing criticism over the pricing of its blockbuster HCV drug Sovaldi (sofosbuvir), and its hepatitis C franchise revenues are falling. Right now, Gilead really needs a near-term drug that will fill the gaps in its pipeline, and in its income stream.
While momelotinib will meet an important need in a niche market, it will be up against Incyte's Jakafi (ruxolitinib), the first and only drug to be approved specifically for myelofibrosis, and these results, though only from a single set of studies, won't give the company the competitive advantage it needs. Analysts from Jefferies said that even if there was some possibility of approval for momelotinib, the niche role in myelofibrosis would be unlikely to move the company's "revenue needle."
Myelofibrosis is a rare form of chronic leukemia. It is leads to scar tissue formation in the bone marrow, anemia and often an enlarged spleen. ETHealthworld expects the market to be worth $1 billion in 2025, almost doubling from its 2015 value of $545.2 million, driven at least partly by increasing incidence.
- Gilead Sciences Statement
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