Experimental psoriatic arthritis treatment filgotinib shows strong response in clinical trials

Gilead Sciences and Galapagos jointly announced results from Phase Two (mid-stage) clinical trials for their JAK1 inhibitor filgotinib for psoriatic arthritis. The companies are jointly developing the investigational treatment. JAK inhibitors, taken as pills, are receiving much attention for their ability to help people with rheumatoid arthritis (RA), psoriatic arthritis, and other conditions.

Xeljanz (tofacitinib), for example, is a JAK inhibitor marketed by Pfizer and currently approved for adults with psoriatic arthritis when non-biologic DMARDs (drugs like methotrexate) do not work well or cannot be tolerated. It is also approved for RA. Rinvoq (upadacitinib), meanwhile, is another JAK inhibitor – this one from AbbVie – approved for RA and is pending before the US FDA for psoriatic arthritis.

Filgotinib looks promising. Of those who achieved a 50% improvement in a set of psoriatic arthritis symptoms after 16 weeks, about 9 in 10 sustained that improvement at the one year mark. Also, one-third of those who had not responded adequately after 16 weeks achieved a 50% improvement by 52 weeks.

The drug is now in both Phase Two and Phase Three trials. A Phase Three trial in psoriatic arthritis – in case you are interested in learning more or participating – is currently enrolling adult patients in the United States. There is also a Phase Two trial of filgotinib in Europe recruiting men with psoriatic arthritis and other diseases.

JAK inhibitors have raised some safety concerns in a small proportion of patients, and do not have the long track record of some of the biologics, but they clearly have caught the attention of rheumatologists and offer psoriatic arthritis patients an important, additional treatment option.

[Last updated 6-9-2020]