Patients with psoriasis treated with interleukin-12/23 inhibitors or IL-23 inhibitors were less likely to develop inflammatory arthritis, compared with those treated with tumor necrosis factor (TNF) inhibitors, according to findings from a large retrospective study.
While previous retrospective cohort studies have found biologic therapies for psoriasis can reduce the risk of developing psoriatic arthritis when compared with other treatments such as phototherapy and oral nonbiologic disease-modifying antirheumatic drugs, this analysis is the first to compare classes of biologics, Shikha Singla, MD, of the Medical College of Wisconsin, Milwaukee, and colleagues wrote in The Lancet Rheumatology.
In the analysis, researchers used the TriNetX database, which contains deidentified data from electronic medical health records from health care organizations across the United States. The study included adults diagnosed with psoriasis who were newly prescribed a biologic approved by the Food and Drug Administration for the treatment of psoriasis. Biologics were defined by drug class: anti-TNF, anti-IL-17, anti-IL-23, and anti–IL-12/23. Any patient with a diagnosis of psoriatic arthritis or other inflammatory arthritis prior to receiving a biologic prescription or within 2 weeks of receiving the prescription were excluded.
The researchers identified 15,501 eligible patients diagnosed with psoriasis during Jan. 1, 2014, to June 1, 2022, with an average follow-up time of 2.4 years. The researchers chose to start the study period in 2014 because the first non–anti-TNF drug for psoriatic arthritis was approved by the FDA in 2013 – the anti–IL-12/23 drug ustekinumab. During the study period, 976 patients developed inflammatory arthritis and were diagnosed on average 528 days after their biologic prescription.
In a multivariable analysis, the researchers found that patients prescribed IL-23 inhibitors (guselkumab [Tremfya], risankizumab [Skyrizi], tildrakizumab [Ilumya]) were nearly 60% less likely (adjusted hazard ratio, 0.41; 95% confidence interval, 0.17–0.95) to develop inflammatory arthritis than were patients taking TNF inhibitors (infliximab [Remicade], adalimumab [Humira], etanercept [Enbrel], golimumab [Simponi], certolizumab pegol [Cimzia]). The risk of developing arthritis was 42% lower (aHR, 0.58; 95% CI, 0.43-0.76) with the IL-12/23 inhibitor ustekinumab (Stelara), but there was no difference in outcomes among patients taking with IL-17 inhibitors (secukinumab [Cosentyx], ixekizumab [Taltz], or brodalumab [Siliq]), compared with TNF inhibitors. For the IL-12/23 inhibitor ustekinumab, all sensitivity analyses did not change this association. For IL-23 inhibitors, the results persisted when excluding patients who developed arthritis within 3 or 6 months after first biologic prescription and when using a higher diagnostic threshold for incident arthritis.
“There is a lot of interest in understanding if treatment of psoriasis will prevent onset of psoriatic arthritis,” said Joel M. Gelfand, MD, MSCE, director of the Psoriasis and Phototherapy Treatment Center at the University of Pennsylvania, Philadelphia, who was asked to comment on the results.
“To date, the literature is inconclusive with some studies suggesting biologics reduce risk of PsA, whereas others suggest biologic use is associated with an increased risk of PsA,” he said. “The current study is unique in that it compares biologic classes to one another and suggests that IL-12/23 and IL-23 biologics are associated with a reduced risk of PsA compared to psoriasis patients treated with TNF inhibitors and no difference was found between TNF inhibitors and IL-17 inhibitors.”
While the study posed an interesting research question, “I wouldn’t use these results to actually change treatment patterns,” Alexis R. Ogdie-Beatty, MD, an associate professor of medicine at the University of Pennsylvania, Philadelphia, said in an interview. She coauthored a commentary on the analysis. Dr. Gelfand also emphasized that this bias may have influenced the results and that these findings “should not impact clinical practice at this time.”
Although the analyses were strong, Dr. Ogdie-Beatty noted, there are inherent biases in this type of observational data that cannot be overcome. For example, if a patient comes into a dermatologist’s office with psoriasis and also has joint pain, the dermatologist may suspect that a patient could also have psoriatic arthritis and would be more likely to choose a drug that will work well for both of these conditions.
“The drugs that are known to work best for psoriatic arthritis are the TNF inhibitors and the IL-17 inhibitors,” she said. So, while the analysis found these medications were associated with higher incidence of PsA, the dermatologist was possibly treating presumptive arthritis and the patient had yet to be referred to a rheumatologist to confirm the diagnosis.
The researchers noted that they attempted to mitigate these issues by requiring that patients have at least 1 year of follow-up before receiving biologic prescription “to capture only the patients with no previous codes for any type of arthritis,” as well as conducting six sensitivity analyses.
The authors, and Dr. Ogdie-Beatty and Dr. Gelfand agreed that more research is necessary to confirm these findings. A large randomized trial may be “prohibitively expensive,” the authors noted, but pooled analyses from previous clinical trials may help with this issue. “We identified 14 published randomized trials that did head-to-head comparisons of different biologic classes with regard to effect on psoriasis, and these trials collectively contained data on more than 13,000 patients. Pooled analyses of these data could confirm the findings of the present study and would be adequately powered.”
But that approach also has limitations, as psoriatic arthritis was not assessed an outcome in these studies, Dr. Ogdie-Beatty noted. Randomizing patients who are already at a higher risk of developing PsA to different biologics could be one approach to address these questions without needing such a large patient population.
The study was conducted without outside funding or industry involvement. Dr. Singla reported no relevant financial relationships with industry, but several coauthors reported financial relationships with pharmaceutical companies that market biologics for psoriasis and psoriatic arthritis. Dr. Ogdie-Beatty reported financial relationships with AbbVie, Amgen, Bristol-Myers Squibb, Celgene, CorEvitas, Gilead, Happify Health, Janssen, Lilly, Novartis, Pfizer, and UCB. Dr. Gelfand reported financial relationships with Abbvie, Amgen, BMS, Boehringer Ingelheim, FIDE, Lilly, Leo, Janssen Biologics, Novartis, Pfizer, and UCB. Dr. Gelfand is a deputy editor for the Journal of Investigative Dermatology.
This article was updated 3/15/23.