A study of seven dialysis patients found that low doses of apixaban, an oral drug that more directly inhibits coagulation than warfarin, can be maintained in the blood at safe levels for potentially preventing strokes. The findings, which appear in an upcoming issue of the Journal of the American Society of Nephrology, indicate that additional research is warranted on the benefits of apixaban in patients with kidney failure.

A team led by Thomas Mavrakanas, MD, and Mark Lipman, MD, from Jewish General Hospital at McGill University, in Canada, assessed the potential of apixaban in seven patients who received 2.5 mg twice daily.

When the researchers collected blood samples, they found significant accumulation of the drug between day one and eight. When apixaban levels were monitored hourly during dialysis, only 4% of the drug was removed. After a five-day washout period, five patients received the currently recommended dose of 5 mg of apixaban twice daily for eight days. This led to dangerously high blood levels of the drug, according to the researchers.

“This dosage should be avoided in patients on dialysis. On the contrary, drug exposure with the reduced dose of 2.5 mg twice daily may be considered in patients on dialysis with atrial fibrillation,” said Mavrakanas, who is currently a research fellow at Brigham & Women’s Hospital in Boston. “No clinical data are yet available, however, and more evidence is necessary before recommending this drug at the 2.5 mg twice daily dose for stroke prevention in patients on dialysis with atrial fibrillation.”