Evaluation of the effect of tofacitinib on measured glomerular filtration rate in patients with active rheumatoid arthritis: results from a randomised controlled trial
Mean increases from baseline in patient serum creatinine (SCr) levels have been observed in the clinical development programme for the JAK inhibitor tofacitinib. These increases predominantly occurred within the first three months, and reversed with tofacitinib withdrawal.
This phase 1, randomised, placebo-controlled, parallel-group, 2-period study assessed changes in measured glomerular filtration rate (mGFR) with tofacitinib, relative to placebo, in 148 patients with active RA. Results showed that mean increases in SCr and mean decreases in estimated glomerular filtration rate (eGFR) in patients treated with tofacitinib 10 mg BID occur in parallel with decreases in mGFR. These changes were reversible following withdrawal of tofacitinib.
When applying these results to clinical practice, the changes in SCr and mGFR in tofacitinib-treated patients with RA should be considered in the context of concomitant medications received and the doses of such medications.
Future clinical studies and routine pharmacovigilance will further assess the long-term and real world renal safety profile of tofacitinib.