A Phase III trial for blood thinner Rivaroxaban (Xarelto) for individuals with acute coronary syndrome met its primary endpoint for efficacy. Rivaroxaban compared to placebo, significantly reduced the rate of myocardial infarction, cardiovascular death and stroke in patients with acute coronary syndrome, German pharmaceutical company Bayer informed.
Risk of major bleeding events not linked to coronary artery bypass graft surgery was higher among those on Rivaroxaban compared to participants on placebo.
Bayer is co-developing Xarelto with Johnson & Johnson.
Last year, Pfizer and Bristol-Myers Squibb failed in their attempt to get apixaban (Eliquis) onto the market.
The two pharmaceutical companies say they are gearing up to apply for approval to regulatory authorities by the end of 2011.
Although both Bayer and J&J are optimistic, experts say the increased bleeding from therapy still leaves the issue of optimal dosage unsolved. When submitting the drug for approval for acute coronary syndrome patients, they will have to make sure the dosages are appropriate for maximum effectiveness and safety.
Xarelto’s key market will continue to be AT (atrial fibrillation). Recently an FDA Advisory Committee recommended approving Xarelto for preventing strokes in patients with atrial fibrillation. Bayer expects Xarelto’s approval for atrial fibrillation patients towards the end of this year, probably in November.
Rivaroxaban, chemical formula C19H18ClN3O5S, is a clot busting (blood thinning, antigoagulant) oral medication manufactured by Bayer and marketed in the USA by Janssen Pharmaceutica (part of Johnson & Johnson). It is the first orally active direct factor Xa inhibitor. Although its effects last from eight to twelve hours, its factor Xa activity does not return to normal for about 24 hours – so it is possible to have it once a day in some cases.
Regulatory approval history
- September 2008 – Health Canada approves once daily, 10 mg tablet rivaroxaban for VTE (venous thromboembolism) prevention in patients who had elective total knee or hip replacement surgery.
- September 2008 – EMA (European Medicines Agency) approves rivaroxaban for same indications as Health Canada (above).
- July 2011 – FDA (Food and Drug Administration), USA, approves rivaroxaban for same indications as Health Canada (above).
- September 2011 – FDA Advisory Committee recommends rivaroxaban for prevention of stroke in patients with atrial fibrillation – members voted 9 to 2 abstaining. The abstainers felt more studies were needed to determine the safety of the direct Xa inhibitor.
Rivaroxaban is surprisingly similar in structure to antibiotic linezolid. Both medications share the same oxazolidinone-derived core structure.
Linezolid (top) and rivaroxaban (bottom). The shared structure is in blue
Written by Christian Nrodqvist