Patients on the Janus kinase inhibitor tofacitinib should be monitored, and warned about signs and symptoms of pulmonary embolism, the TGA says.

The product information has been updated to include details from an ongoing safety study that linked high doses (10mg twice daily) to increased risk of blood clots and death.

The sponsor of tafacitinib (Xeljanz), Pfizer Australia, wrote to doctors in March, saying that a clinical trial had found an increased risk of clots in the lung and overall mortality when a 10mg twice-daily dose was prescribed compared with 5mg twice-daily in patients with rheumatoid arthritis (RA). 

All participants in the trial had RA and at least one other cardiac risk factor. They had all previously been treated with methotrexate.