- An analysis of medical and pharmacy claims from the U.S. Medicare database showed Bristol-Myers Squibb and Pfizer's new blood-thinner Eliquis (apixaban) significantly cut the risk of stroke and major bleeding compared to warfarin, giving the drugmaker a new card to play in promoting the anti-coagulant.
- Eliquis also proved more cost-effective in reducing risk than warfarin, saving about $250 in major bleed-related costs on a per patient per month basis, according to data from the real-world study, which was sponsored by Bristol-Myers and Pfizer.
- The drug is part of a class of novel oral anti-coagulants (NOACs) that includes Johnson & Johnson's Xarelto (rivaroxaban) and Boehringer Ingelheim's Pradaxa (dabigatran). Eliquis and Xarelto have quickly become blockbuster products, but many patients are still treated with standard warfarin.
Bristol-Myers and Pfizer's study relied on what's known as real-world evidence, in this case claims data from over 186,000 non-valvular atrial fibrillation patients age 65 and older in Medicare's database. While lacking the comparative rigor of randomized clinical trials, real-world studies look set to become a larger part of the picture in evaluating a drug's benefit — particularly in post-approval settings after a drug's safety and efficacy has been established.
Since real-world studies focus on outcomes in medical practice, they can provide an important complement to the narrow focus of a clinical trial. Results, though, are dependent on accurate records and coding of claims, while other factors can impede the randomization that gives clinical trials their statistical heft.
Researchers for the study divided patients into three cohorts, each comparing groups of patients prescribed either Eliquis, Pradaxa or Xarelto to another matched set prescribed warfarin.
The analysis, which was presented at the annual meeting of the American College of Cardiology, found Eliquis performed better versus warfarin than either of its rival NOACs.
Treatment with Eliquis reduced the risk of stroke by 60% and major bleeding by 49%, compared to warfarin. Xarelto also cut stroke risk, but only by 28% and Pradaxa's risk reduction wasn't statistically significant. More surprisingly, however, was that Xarelto failed to reduce the risk of major bleeds versus warfarin.
On the cost side, Eliquis's performance versus warfarin also compared favorably to Xarelto and Pradaxa. Eliquis led to savings of $251 in major bleed-related costs compared to warfarin, while Pradaxa only saved $85 versus the vitamin K agonist. Costs associated with Xarelto appeared similar to that of warfarin.
The cost associated with the use of each NOAC were not directly compared against each other, however.
"What we found, in particular with apixaban consistently across different databases, is that by reducing the number of strokes and major bleeds we can completely offset the pharmaceutical cost," said Cristina Masseria, a health economics researcher from Bristol-Myers' partner Pfizer.
In the case of anti-coagulation therapy, preventing major bleeds translates to reduced costs as treating bleeding episodes can be expensive and labor-intensive.
While Eliquis appeared more competitive than its peers, Boehringer's Pradaxa has one advantage going for it — an approved reversal agent designed to undo the anti-coagulation effect of Pradaxa in emergencies. A universal antidote to Factor Xa inhibitors like Eliquis and Xarelto is currently in development but not yet approved.
Even so, Bristol-Myers' Christoph Koenen, development lead for Eliquis, indicated the company doesn't see a reversal agent as a crucial factor to support Eliquis' growth. "We still believe it is going to be good to have a reversal agent. But it is not going to be essential to make sure patients as well as healthcare professionals use Eliquis."