Safety of Biologics Approved for the Treatment of Rheumatoid Arthritis and Other Autoimmune Diseases: A Disproportionality Analysis from the FDA Adverse Event Reporting System (FAERS).

Introduction: The molecular and pharmacological complexity of biologic disease-modifying antirheumatic drugs used for the management of rheumatoid arthritis (RA) favors the occurrence of adverse drug reactions (ADRs), which should be constantly monitored in post-marketing safety studies.

Objective: The aim of this study was to identify signals of disproportionate reporting (SDR) of clinical relevance related to the use of biologic drugs approved for RA and other autoimmune diseases.

Methods: All suspected ADRs registered in the FDA Adverse Event Reporting System between January 2003 and June 2016 were collected. The reporting odds ratio was used as a measure of disproportionality to identify possible SDRs related to biologics. Those involving important medical events and designated medical events (DME) were prioritized.

Results: In total, 2602 SDRs were prioritized. The most commonly reported were 'Infections and infestations' (32.2%) and 'Neoplasms benign, malignant, and unspecified' (20.4%), and were mainly related to use of infliximab (25.3%, p < 0.001, and 28.8%, p = 0.002, respectively). Sixty-three signals involving DMEs were identified, most of which were related to rituximab (n = 27), and were mainly due to 'blood disorders'. Amongst the DMEs detected for more than one biologic, 'intestinal perforation' and 'pulmonary fibrosis' were related to most of them.

Conclusions: The results of this study highlight possible safety issues associated with biologics, whose relationship should be more thoroughly investigated. Our results contribute to future research on the identification of clinically relevant risks associated with these drugs, and may help contribute to their rational and safe use.