A major study of the blood-thinner Xarelto (rivaroxaban) has handed Johnson & Johnson ($JNJ) and Bayer just the kind of data they believe regulators can pin an approval on for the elusive acute coronary syndrome market. Two low doses in the study reduced deaths in the ACS group, possibly opening the door to a billion-dollar market. But a number of experts are still fretting over the increased threat of bleeding and whether regulators would green-light a treatment without a closer consideration of real-world safety issues.
The low-dose groups in the study, which recruited 15,526 patients, demonstrated a 16% reduction in heart attacks, strokes and cardiovascular deaths. Those two doses are one-half or one-quarter--a 2.5 milligram dose--of the strength used for the atrial fibrillation population, helping reduce the chances of bleeding.
"Xarelto appears to have hit the 'sweet spot' for efficacy with an acceptable safety profile," noted Leerink Swann analyst Seamus Fernandez, as reported by Bloomberg. The data sets up an FDA approval for a treatment that "can be a meaningful competitor in an increasingly crowded space that has been relatively slow to develop commercially."
Not so fast, say some experts in the field. "I worry that if you are going to release a drug like this into the real world, you are going to deal with bleeding incidents and the payoff may not be there," specialist Jack Ansell told Bloomberg. And Reuters' story carries a number of cautionary remarks.
"The initial commercial potential looks limited, given the increased bleeding risks seen with Xarelto in the trial," Deutsche Bank analysts stated. "We expect use in ACS to be limited, given the availability of newer, more potent anti-platelet regimes such as AstraZeneca's Brilinta that improve outcomes with less increased bleeding."
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