Rheumatoid arthritis patients on anti–tumor necrosis factor medications had approximately twice the rate of serious adverse events as did psoriasis patients on the same medications, based on data from a pair of prospective studies of about 4,000 adults.
The findings were published online in the British Journal of Dermatology.
“Current trends are to extrapolate the abundant literature existing on the safety of TNF antagonists in RA to define safety management for psoriasis,” wrote Dr. Ignacio García-Doval of the Fundación Academia Española de Dermatología y Venereología, Madrid, and colleagues. However, data on the similarity of risk associated with anti-TNF medications in RA and psoriasis are limited, the investigators said (BJD. 2016. doi: 10.1111/bjd.14776).
The researchers compared data from two similarly designed, overlapping prospective safety registry studies of anti-TNF medications in RA patients (the BIOBADASER study) and psoriasis patients (the BIOBADADERM study).
In the cohort of 3,171 RA patients, the researchers identified 1,248 serious or fatal adverse events during 16,230 person-years of follow-up; in the cohort of 946 psoriasis patients, they identified 124 serious or fatal adverse events during 2,760 person-years of follow-up. The resulting incidence rate ratio of psoriasis to RA was 0.6. The increased risk of serious adverse events for RA patients compared with psoriasis patients remained after the investigators controlled for confounding factors including age, sex, treatments, and comorbid conditions including hypertension, diabetes, hypercholesterolemia, and methotrexate therapy, for a hazard ratio of 0.54.
Moreover, the types of serious adverse events were different between the RA and psoriasis groups. Among those with RA, the rates of serious infections, cardiac disorders, respiratory disorders, and infusion reactions were significantly greater among those with RA, while psoriatic patients “had more skin and subcutaneous tissue disorders and hepatobiliary disorders,” the researchers noted.
By contrast, “rates of nonserious adverse events cannot be compared between the two cohorts,” because of differences in definitions, they pointed out. These differences resulted in a nonserious adverse event rate that was more than twice as high in the psoriasis group as in the RA group (582.2 events per 1,000 patient-years vs. 242.8 events per 1,000 patient-years).
Based on the findings, “published safety results of TNF-antagonists in RA cannot be fully extrapolated to psoriasis, as patients with RA have a higher risk and a different pattern of serious adverse events,” they concluded.
The BIOBADADERM project is promoted by the Fundación Academia Española de Dermatología y Venereología, which is supported by the Spanish Medicines and Health Products Agency and by multiple pharmaceutical companies. BIOBADASER received funding from Fundacion Española de Reumatología and the Spanish Medicines and Health Products Agency and grants from numerous pharmaceutical companies. Lead author Dr. Garcia-Doval disclosed travel grants for congresses from Merck/Schering-Plough Pharmaceuticals, Pfizer, and Janssen; the remaining two authors disclosed being a speaker and/or a consultant for several companies, including AbbVie.