Janus kinase inhibitors: efficacy and safety

Janus kinase inhibitors (JAKi) have been available for the treatment of rheumatoid arthritis (RA) since 2012 and are indicated for patients with active disease despite csDMARD therapy. Efficacy and safety, as demonstrated in the clinical trials, was similar to biologics. A recent post marketing trial suggested safety concerns with the JAKi, which will be reviewed.

A post marketing Food and Drug Administration (FDA) mandated open-label randomized clinical trial of tofacitinib 5 and 10 mg twice daily (b.i.d.) compared with adalimumab and etanercept was conducted in RA patients on background methotrexate who were at a high risk for cardiovascular disease. This was a noninferiority study evaluating the incidence of major adverse cardiovascular events (MACE) and malignancy with the therapies. Noninferiority for both doses of tofacitinib was not achieved with a numerical increase in MACEs and malignancy with tofacitinib compared to the TNF inhibitors. A dose-dependent increase in venous thromboembolism (VTE) risk with tofacitinib was observed. The findings from this study resulted in the FDA and European Medicines Agency (EMA) restriction of use for all Jaki to RA patients who had failed TNF inhibitors.

JAK inhibitors are effective treatments for RA. Issues have been raised regarding safety in patients with an increase in cardiovascular risk and VTE risk resulting in the need for risk stratification.