Portola Pharmaceuticals Inc. reported that it has developed an experimental drug to reverse the effects of Xarelto, a blood-thinning drug co-developed by Bayer and Johnson & Johnson. One shot of the drug, known as andexanet alfa, immediately reversed Xarelto’s anticoagulation activity in patients aged 50 to 75.
Xarelto, which was designed to help prevent blood clots in stroke patients and treat deep vein thrombosis, has been found to increase the risk of severe side effects, including pulmonary embolism and uncontrollable bleeding. The drug also did not contain a natural antidote, which could potentially increase the risk of severe complications associated with Xarelto.
The U.S. Food and Drug Administration ordered Bayer and Johnson & Johnson to conduct more research regarding the efficacy and risks of Xarelto after the companies attempted to have it approved for more uses in 2014. Nearly 2,000 cases of severe Xarelto side effects have been documented, including 183 deaths associated with Xarelto.