Gilead and Galapagos' JAK Inhibitor Stumbles in Mid-Stage Lupus Trial

Despite the success Gilead Sciences has seen with its JAK inhibitor filgotinib in rheumatoid arthritis, the medication failed to hit the mark in mid-stage trials aimed at lupus and Sjogren's syndrome.

During its third quarter conference call, Gilead’s clinical research head John Sundy said filgotinib did not hit its primary endpoints in the trials. But, the company did see “evidence of activity” with filgotinib, particularly in patients who had evidence of more active disease, Sundy said, according to a transcript of the call posted on Seeking Alpha.

While no data was shared, Sundy said the company will provide the information at an upcoming meeting. The two studies were initiated in 2017 with Gilead’s development partner Galapagos. Lupus is an autoimmune disease affecting multiple organs and systems in the body, resulting in a wide variety of signs and symptoms. Cutaneous lupus erythematosus, which is what filgotinib was being developed for, is a form of lupus in the skin which can be triggered or exacerbated by exposure to sunlight.

Walid Abi-Saab, chief medical officer of Galapagos, confirmed the activity generated by filgotinib on his company’s third quarter call. While the trials failed to hint the endpoints, Abi-Saab indicated that some form of trial could continue with sub-populations of patients, Pharmaphorum reported.

Sjogren's syndrome is an autoimmune disease where the body’s immune system attacks the glands that make saliva and tears, which results in dry mouth and dry eyes. It can also impact other moisture-producing parts of the body, including the nose, throat and skin. The disease can also affect the lungs, joints, liver, kidneys and other internal parts.

In addition to filgotinib, both the lupus and Sjogren's studies included lanraplenib (GS-9876), a Syk kinase inhibitor. In the brief moment Sundy spoke of the trials on the call, he noted that the two companies had “set a high bar for ourselves to proceed.”

Gilead and Galapagos are planning to file a New Drug Application for filgotinib as a treatment for rheumatoid arthritis. The filing will be based on positive results from the Phase III FINCH 1 and Finch 3 trials. Both trials showed efficacy and a consistent safety profile for the drug. That NDA will be bolstered by long-term safety data released earlier this month. If approved, filgotinib would become the fourth JAK inhibitor approved for RA. Other JAK inhibitors on the market are Pfizer’s Xeljanz, Eli Lilly’s Olumiant and AbbVie’s Rinvoq, which was approved by the U.S. Food and Drug Administration in August.