AbbVie, the North Chicago company behind the longtime blockbuster biologic Humira (adalimumab) and a new biologic Skyrizi (risankizumab-rzaa), moved closer this week to having its new rheumatoid arthritis (RA) pill, Rinvoq (upadacitinib), approved for psoriatic arthritis. Rinvoq is a JAK inhibitor being studied for psoriatic arthritis as a once-daily pill.
The company reported preliminary results of a Phase Three clinical trial of Rinvoq in adults with active psoriatic arthritis who had been unsuccessfully treated with at least one biologic, indicating that the drug significantly beat placebo (a pill with no active ingredient) in the percentage of patients who achieved at least a 20% improvement in joint arthritis, and in the percentage who achieved at least a 75% improvement in skin psoriasis. While there are potential side effects with JAK inhibitors, in this trial they were apparently in line with what has previously been seen in RA. The company says full results will be published at a future date.
JAK inhibitors fight psoriatic disease differently than the biologics, offering patients a new treatment option. They are also taken as a pill rather than by injection or infusion, an option seen as attractive to many. It is not yet clear, though, if any JAK inhibitors will be able to clear psoriasis as effectively as biologics. Xeljanz, a JAK inhibitor from Pfizer that is US Food and Drug Administration (FDA) approved for psoriatic arthritis, has shown effectiveness in skin psoriasis but is not currently FDA-approved for that.
AbbVie’s Skyrizi, meanwhile, is FDA-approved for psoriasis, and in Phase Three trials for psoriatic arthritis, where it is performing well. Interestingly, AbbVie put Skyrizi in a psoriasis clinical trial head-to-head against its own blockbuster, Humira, where Skyrizi came out on top. That’s good news for psoriasis patients, but also for AbbVie shareholders, since Humira’s patents are starting to wind down, and biosimilars for Humira will appear in the United States in the fall of 2023. Skyrizi, with its impressive results in psoriasis – including complete clearing of the skin in many cases – is self-injected under the skin just once every 12 weeks after initial “loading” doses.
[Last updated 11-1-2019]