By Angela Maas

For many years, the psoriasis treatment landscape was dominated by tumor necrosis factor (TNF) inhibitors. But with the FDA’s approval of three interleukin-17 (IL-17) inhibitors — as well as other drugs with different mechanisms of action — for the condition, those therapies are becoming more common among treatment regimens.

The first IL-17 inhibitor on the U.S. market was Cosentyx (secukinumab) from Novartis Pharmaceuticals Corp., which launched in 2015. The next therapy was Taltz (ixekizumab) from Eli Lilly and Co., and then on Feb. 15, 2017, the agency approved Siliq (brodalumab) from Ortho Dermatologics.

An AllianceRx Walgreens Prime study sampled 5,215 members who started on an IL-17 from January 2016 through December 2017. The study showed that 2,218, or 42.5%, switched from a prior biologic, while 2,997, or 57.5%, started on an IL-17 as their first psoriasis biologic. Among those who started their biologic regimens on an IL-17 inhibitor, 2,266 started on Cosentyx, followed by 725 who initiated on Taltz and six who started on Siliq.

Researchers also examined 180-day adherence outcomes among members who switched to an IL-17 inhibitor from another biologic, as determined by proportion of days covered (PDC). The mean PDC increase after moving to an IL-17 was 6.4%.

Among those moving to an IL-17, 45.7% said their outcomes were better, 26.5% said they were the same, 5.3% said they were worse, and 22.6% said they were inconsistent.

According to Renee Baiano, Pharm.D., clinical program manager at AllianceRx Walgreens Prime and the lead author of the poster, the main takeaway for payers is that “by [the] last quarter of 2017, IL-17 inhibitors may have gained clinical acceptance in the treatment of psoriasis, given the increase in patients prescribed as their first biologic.” She adds that “it is important for payers to be aware they may see more of their members being prescribed IL-17 inhibitors and will need to determine the appropriate placement of these newer agents within their formulary.”