Safety and Effectiveness of Tofacitinib in Treating Polyarticular Course Juvenile Idiopathic Arthritis

Polyarticular course juvenile idiopathic arthritis (pcJIA) is a form of arthritis that affects at least five joints at a time and presents before the age of 16. Its most common symptoms are pain, swelling, redness, and a limited range of motion, making it incredibly difficult for patients diagnosed to function in daily life. Historically, the leading treatment options have consisted of non-steroidal anti-inflammatory drugs (NSAIDs) and disease-modifying antirheumatic drugs (DMARDs) such as methotrexate. However, these drugs have serious toxic side effects associated with long-term use in addition to being ineffective in refractory cases. Recently, small molecule biologics have emerged as an alternate treatment to pcJIA. Tofacitinib is a small molecule JAK inhibitor that blocks the JAK/STAT cascade and decreases the transcription of genes responsible for immune function. We conducted a risk-benefit analysis to determine the viability of tofacitinib as a treatment for pcJIA. In our review, we found the side effect profile of tofacitinib to be relatively mild, with many of the serious adverse side effects occurring in those immunocompromised and those with impaired renal and hepatic metabolism. Overall, we have determined that tofacitinib has the potential to be effective in reducing flare-ups and lowering erythrocyte sedimentation rate (ESR) in immunocompetent patients with pcJIA. Additionally, our review has found that tofacitinib has the potential to be effective in patients who are refractory to traditional treatment. However, large-scale clinical trials are needed to determine if this effect holds true in younger pediatric populations, as limited data surrounds this demographic.