UPDATED: J&J-Bayer and Pfizer-BMS look for marketing advantages in real-world Xarelto, Eliquis data

LONDON--Johnson & Johnson and Bayer are leading the four-horse race among new-age anticoagulants, and they're hoping some new real-world safety data for Xarelto can help keep the med in the No. 1 spot.

Tuesday, the companies announced low major bleeding rates among atrial fibrillation patients from a pair of studies. An ongoing, 39,052-patient U.S. study, dubbed PMSS, found an incidence of major bleeding measuring 2.89 per 100 person-years, while XANTUS, a 6,784-patient study looking at atrial fibrillation sufferers in Europe, Canada and Israel, registered a rate of 2.1.

Both of those findings are in line with the safety profile Xarelto displayed in ROCKET AF, the Phase III study on which regulatory authorities based their approvals, Dr. Paul Burton, VP of medical affairs for J&J's ($JNJ) Janssen unit, told FiercePharma in an interview at the European Society of Cardiology Congress.

Janssen's Dr. Paul Burton

The real-world studies are "really asking the question, okay, we know how the drug behaves in the clinical trial, but how does it behave in a well-conducted, robust, prospectively designed real-world safety study? And the answer is, it behaves very well," he said. "It's very reassuring."

A rival team of Bristol-Myers Squibb ($BMY) and Pfizer ($PFE), though--whose Eliquis currently sits in the No. 3 spot behind Xarelto and first-to-market Pradaxa—had real-world data of its own to tout at the conference. In one comparative assessment looking at 29,338 atrial fibrillation patients new to Eliquis, Xarelto, Pradaxa or old-guard therapy warfarin, starting on Xarelto or warfarin posed "significantly greater" major bleeding risks compared with Eliquis, according to the study abstract.

"Consistently, we're demonstrating significant reductions in major bleeding" when comparing Eliquis with Xarelto and warfarin," Sonal Bhatia, a senior medical director at Pfizer, told FiercePharma in an interview.

As Burton pointed out in a statement, though, "real-world research is an essential complement to clinical trials and helps inform treatment decisions," but "it does not replace them." A head-to-head clinical trial is "the most accurate way to assess comparative safety profiles" of the two drugs, he said.

After getting off to a slow start, Eliquis has recently been gaining ground, thanks in part to an amped-up DTC push from Pfizer and BMS. And as Bayer's management told Bernstein analyst Ronny Gal in June, "the impression that Eliquis is a better drug exists in the marketplace," and the German pharma and J&J have been doing their best to combat that notion.

Unlike its rivals, though, Xarelto also has an extensive clinical research program aimed, in part, at scoring label expansions for the market leader. Among other potential indications, J&J and Bayer are testing the drug in patients with acute coronary syndrome, a wide patient population that could bring the med a hefty sales boost. It's a tough market, though; FDA has already rejected Xarelto in ACS three times.

For Eliquis, on the other hand, answering "important questions" within the drug's existing indications is "what we're focused on in our clinical development program right now," Bristol's VP and head of cardiovascular medical Christoph Koenen told FiercePharma, though he declined to discuss any further studies the companies were planning.

- read Janssen's release
- view the abstract

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