CARDIOVASCULAR

Thinning out the options

New FDA-approved anticoagulants being evaluated by U-M physicians

issue 23 | spring 2015

For more than 60 years, warfarin was the sole prescription anticoagulant approved for use in the United States. Finally, there are more options: In the past five years, the U.S. Food and Drug Administration has approved four new oral anticoagulants as alternatives to warfarin:

  • Dabigatran (brand name Pradaxa)
  • Rivaroxaban (brand name Xarelto)
  • Apixiban (brand name Eliquis)
  • Edoxaban (brand name Savaysa)

The U-M Anticoagulation Management System is participating in the Michigan Anticoagulation Quality Improvement Initiative (MAQI2) — a multicenter, regional collaborative registry investigating the safety, quality and outcomes of anticoagulation treatment.

"As part of this collaboration, we now manage patients on warfarin and the new agents," says James Froehlich, M.D., M.P.H., medical director of the University of Michigan Anticoagulation Service and professor of Internal Medicine. "There's no doubt that the new anticoagulants are less problematic than warfarin in some ways, but they also introduce new issues. We're looking at the data to determine each drug's pros and cons."

Warfarin has a long history as an effective, safe and inexpensive medication, although the drug does come with "tricky challenges that the new anticoagulants don't have," stresses Geoff Barnes, M.D., clinical lecturer in Cardiovascular Medicine at U-M. "Warfarin's biggest challenges involve frequent blood tests, monitoring and dosage adjustments to avoid bleeding problems. The new anticoagulants require no blood draws and minimal management."

There are also dangerous food and drug interactions associated with warfarin, of which there are far fewer with the new anticoagulants. In addition, warfarin requires several days to take effect or completely leave the body, while the new anticoagulants need only hours at both ends. "It's not safe to be on a blood thinner during certain procedures," Barnes stresses. "So for those on warfarin, that means a lot of extra monitoring and management before and after procedures. It's just not an issue with the newer anticoagulants."

The dominant known disadvantage to the new anticoagulant agents is cost. U-M research suggests that the overall health care cost of anticoagulation therapy using the expensive new drugs could potentially be mitigated by fewer doctor visits, blood draws and complications. However, insurers currently consider these drugs second-line therapy and impose higher coinsurance or copay burdens on patients. Froehlich is hopeful that once insurers realize the savings these drugs will bring them down the line, they will re-evaluate coverage decisions.

"I see the cost issue disappearing soon — for at least some of these new agents," Froehlich concludes. "These medications offer too many advantages to be relegated to second class status."