CHICAGO – Patients with atrial fibrillation who start treatment with a new oral anticoagulant may spend more on their medication than if they were prescribed generic warfarin, but their overall health care costs may wind up being about the same, based on an analysis of health care expense records for more than 4,500 U.S. patients.
“Despite higher anticoagulant costs, total all-cause and atrial fibrillation–related costs remain comparable” between patients prescribed warfarin and those who received the new oral anticoagulant rivaroxaban (Xarelto), said Concetta Crivera, Pharm.D., at the American Heart Association Scientific Sessions. Higher drug costs for daily treatment with rivaroxaban were offset by reduced hospital lengths of stays and hence reduced hospitalization costs, said Dr. Crivera, director of cardiovascular health economics and outcomes research at Janssen in Raritan, N.J., the company that markets rivaroxaban along with Bayer.
“I can believe that hospitalized days would be reduced because patients treated with rivaroxaban or any of the other new oral anticoagulants don’t need to remain in the hospital while you wait for their international normalized ratio to enter the therapeutic range,” which is what happens with patients treated with warfarin, commented Dr. Jeffrey Weitz, professor of medicine and director of the Juravinski Hospital and Cancer Centre of McMaster University in Hamilton, Ont.
The new findings by Dr. Crivera “are not definitive on their own, but they add to a growing body of data that indicate that all the new oral anticoagulants are cost effective,” said Dr. Weitz, who specializes in thrombosis and anticoagulants. “The worst time for a patient on warfarin is when they start treatment. You do a disservice to patients with new-onset atrial fibrillation by using warfarin, because some patients will get into the therapeutic range but others never will. That’s why the new oral anticoagulants are better, because everybody gets into therapeutic range,” he said in an interview.
Dr. Crivera and her associates conducted a retrospective study of health records for 2,253 patients with nonvalvular atrial fibrillation (AF) who started anticoagulation treatment with rivaroxaban during the period of November 2011 (when the drug received U.S. marketing approval) through December 2012. The data came from the patient records of Humana, a U.S. HMO and insurer that covers both commercially insured patients and those covered by Medicare. The researchers matched each of the patients initiating rivaroxaban treatment with a similar patient from the Humana database with nonvalvular AF who started on warfarin during the same period. The average age of patients in the study was about 74 years, and patients in the two groups were closely matched for their demographic and clinical characteristics, including comorbidities. Data on health care use were available for patients for an average of about 4 months following their start of anticoagulant treatment.
The analysis showed that during the first months on treatment, patients prescribed rivaroxaban averaged 2.11 days of hospitalization for an AF-related episode, compared with 3.02 days for those prescribed warfarin, a statistically significant difference. Hospitalizations for any cause averaged a total of 2.71 days in the rivaroxaban group and 3.87 days in the patients on warfarin, also a significant difference, Dr. Crivera reported.
This difference in days hospitalized translated into reduced hospitalization costs, a roughly $2,000 average difference per patient in actual hospitalization costs in favor of the rivaroxaban patients for all-cause hospitalizations, and an average $1,300 difference per patient for hospitalization costs directly related to AF.
Although the rivaroxaban patients spent an average of $2,700 more per patient on pharmaceuticals for all causes, and an average $2,200 more for AF-related drugs, the total average all-cause and AF-related costs for drugs, hospitalizations, outpatient visits, and emergency department visits were similar in the two subgroups: an average total of $17,590 per patient for the rivaroxaban patients and $18,676 for warfarin patients for all causes, and an average of $7,394 for the rivaroxaban patients and $7,319 for those on warfarin for AF-related care. The between-group differences for both sets of total costs were not statistically significant.
The study was sponsored by Janssen, which along with Bayer markets rivaroxaban (Xarelto). Dr. Crivera is a Janssen employee. Dr. Weitz has been an adviser or a consultant to Janssen and Bayer and to Boehringer Ingelheim, Bristol-Myers Squibb, Daiichi Sankyo, Johnson & Johnson, Merck, Pfizer, and Portola.
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