Galapagos NV (Euronext & Nasdaq: GLPG) and Gilead Sciences (Nasdaq: GILD) today announced the decision to halt the ISABELA Phase 3 clinical studies with the investigational autotaxin inhibitor ziritaxestat in patients with idiopathic pulmonary fibrosis. The decision is based on the recommendations of the Independent Data Monitoring Committee (IDMC) which, following a regular review of unblinded data, concluded that ziritaxestat’s benefit-risk profile no longer supported continuing these studies. Detailed data of the ISABELA studies will be presented at future medical meetings.

Investigators are being informed of the decision and they will be contacting their study participants to discontinue the investigational treatment.

The ISABELA Phase 3 program consists of two identically designed trials, ISABELA 1 & 2, aiming to enroll 1,500 IPF patients combined. Patients continued on their standard of care background treatment and were randomized on to either 200 mg or 600 mg ziritaxestat once daily or placebo. The primary endpoint was the rate of decline of forced vital capacity until week 52.

“We are very disappointed not to be able to bring a novel medication to patients suffering from such a devastating disease with high unmet need. We would like to thank the patients and the medical professionals who participated in the ISABELA studies and contributed to the advancement of IPF research. We intend to learn from this data in our continued commitment to develop therapies in IPF and fibrosis,” said Dr. Walid Abi-Saab, Chief Medical Officer of Galapagos.

“We are extremely disappointed by this news. Despite this setback, we remain committed to leveraging our novel target research engine and strong cash balance to discover potential therapies for IPF and fibrosis,” said Onno van de Stolpe, CEO of Galapagos.

Ziritaxestat (GLPG1690) is an investigational autotaxin inhibitor discovered by Galapagos. Gilead in-licensed ex-European rights to ziritaxestat in July 2019 and commenced sharing the Phase 3 development costs.

All clinical trials with ziritaxestat, including the long-term extension of the Phase 2a NOVESA trial in systemic sclerosis, will be discontinued.