The US Food and Drug Administration (FDA) has issued a warning regarding pulmonary embolism risk and increased overall mortality in Pfizer’s postmarketing trial assessing Xeljanz (tofacitinib) in rheumatoid arthritis patients.
The trial is intended to investigate the safety of 5mg and 10mg twice-daily Xeljanz, particularly the risk of cardiovascular events, cancer, and opportunistic infections.
A review of study data by the Data Safety Monitoring Board revealed the safety risks in patients administered with 10mg of the drug.
Pfizer transitioned patients from 10mg to 5mg of Xeljanz to address the risks.
FDA Center for Drug Evaluation and Research director Janet Woodcock said: “The FDA is actively examining the data from the trial and working directly with Pfizer to better understand the safety signal, its impact on patients, and how tofacitinib should be used.
“We are communicating now, given the serious nature of the safety issue, to ensure that patients taking tofacitinib are aware that the FDA still believes the benefits of taking tofacitinib for its approved uses continue to outweigh the risks.”
Xeljanz is a Janus kinase (JAK) inhibitor approved by the FDA to treat adults with moderately to severely active rheumatoid arthritis, active psoriatic arthritis and moderately to severely active ulcerative colitis.
Patients treated with the drug are said to be at a higher risk of developing serious infections that could lead to hospitalisation or death.
The FDA approved the drug in 2012 and asked Pfizer to conduct the postmarketing trial in order to ensure safety.
The open-label, endpoint-driven study compares tofacitinib to a tumour necrosis factor inhibitor (TNFi) control group. The trial is ongoing and will be continued through to completion.