(HealthDay News) – Primary venous thromboembolism prophylaxis with apixaban, an oral direct Factor Xa inhibitor, in ambulatory cancer patients undergoing first- or second-line chemotherapy for advanced or metastatic cancer, is safe and well tolerated, according to a phase II study published online March 12 in the Journal of Thrombosis and Haemostasis.
Mark N. Levine, MD, of McMaster University in Hamilton, Canada, and colleagues conducted a randomized phase II trial of oral apixaban in patients with advanced or metastatic lung, breast, gastrointestinal, bladder, ovarian, myeloma, or prostate cancers. Subjects receiving either first- or second-line chemotherapy were randomized to 5mg (32 patients), 10mg (30 patients), or 20mg (33 patients) once a day of apixaban or placebo (30 patients) for 12 weeks. Administration of the study drug began within four weeks of chemotherapy initiation.
The researchers found that there were no major bleeds for those taking 5mg or 10mg apixaban, two major bleeds among patients taking 20mg, and one major bleed in the placebo group. The corresponding numbers of clinically relevant non-major bleeds were one, one, two, and zero. There was a 2.2% rate of major bleeding in the apixaban patients, with no fatal bleeds. Three patients in the placebo group had symptomatic venous thromboembolism (VTE).
“These results support further study of apixaban in Phase III trials to prevent VTE in cancer patients on chemotherapy,” the authors write.
The study was funded by Bristol-Myers Squibb and Pfizer Inc., which manufacture apixaban; two authors are employed by Bristol-Myers Squibb.