Galapagos, Gilead start phase 3 trial of filgotinib in Crohn’s

Galapagos and Gilead have dosed the first patient in a phase 3 Crohn’s disease trial of JAK1 inhibitor filgotinib. The initiation of the study sends the partners barreling toward pivotal data in an indication Gilead sees as a key component of its $2 billion (€1.9 billion) deal with Galapagos.

Gilead and Galapagos will enroll 1,320 subjects with moderately to severely active Crohn's disease, including patients who have tried drugs such as Johnson & Johnson’s Remicade and Takeda’s Entyvio without success. The dosing of the first patient triggered a $50 million milestone payment to Galapagos.

Over the first 10 weeks, participants will receive one of two doses of filgotinib—including the 200-mg dose linked to testicular toxicity—or a placebo. Subjects who achieve clinical remission or endoscopic response will advance into a maintenance study, in which they will take daily doses of filgotinib or a placebo for 58 weeks. The maintenance trial is also primarily looking at rates of clinical remission and endoscopic response.

Gilead and Galapagos expect to complete the trial late in 2019. The partners hope that timeline will give them a shot at carving out a slice of the Crohn’s disease market before competition intensifies. AbbVie, which dropped filgotinib to advance its own JAK1 inhibitor, is yet to post data from a phase 2 trial of its rival drug in Crohn’s disease. The last data against the primary outcome measures—clinical and endoscopic remissions—are due to be collected this month.

That head start contributed to Gilead CEO John Milligan talking up the prospect of filgotinib making the company a leader in Crohn’s disease in September. At the same event, Milligan called rheumatoid arthritis—the other indication being pursued by the JAK1 inhibitors—a “very competitive area.”

Notably, rheumatoid arthritis is a competitive area in which filgotinib trails AbbVie’s ABT-494, which entered phase 3 months ahead of Gilead and Galapagos’ drug. In recent months, the partners have rolled out a clutch of trials to ensure ABT-494 stays in their sights. All three filgotinib phase 3 studies are now enrolling. A phase 2b/3 trial in ulcerative colitis is also due to start imminently.