As the third lawsuit against Janssen Pharmaceuticals and Bayer AG gets underway, the Institute for Safe Medication Practices (ISMP) has released a disturbing report: the number of injuries and fatalities attributed to the anticoagulant medication Xarelto in 2016 was up by more than 40 percent over the previous year.

According to the organization’s annual Quarter Watch, released last month, the U.S. Food and Drug Administration received a total of 15,043 adverse event reports related to Xarelto. Such medications, which include Xarelto (rivaroxaban), Eliquis (apixaban) and Pradaxa (dabigatran), were the cause of more visits to emergency rooms in 2016 than any other class of prescription medications. Of the five drugs of this class known to cause serious and fatal hemorrhaging, Xarelto has been leading the way, accounting for over 68 percent of those injuries and deaths.

The news could not have come at a worse time for the corporate defendants. Currently, drugmakers Janssen (a subsidiary of Johnson & Johnson) and German-based Bayer AG are facing over 18,000 lawsuits from plaintiffs alleging that their injuries were caused by Xarelto and that the manufacturers failed to warn patients and doctors of the dangers. At the same time, Bayer has reduced its expectations for the coming fiscal year, cutting its profit forecast in the wake of falling sales and reduction in stock value.

Despite litigation over the “blood thinning” prescription drug, Xarelto continues to be Bayer’s top-selling product. Last year, Xarelto accounted for nearly one-third of Bayer revenue, with approximately $975 million in sales. That revenue has come at a high cost to health care consumers, and may represent ill-gotten gains. Last year, the New York Times published an article about a shocking allegation: a letter to the New England Journal of Medicine, written by researchers at Duke University, omitted key data about Xarelto – and the manufacturers said nothing about it.

Xarelto is one of a number of “next-generation” anticoagulant medications, sometimes erroneously described as “blood thinners.” It’s what as known as a “Factor Xa (10-A) inhibitor,” which prevents the formation of thrombin, an enzyme that enables the formation of clots in the blood.

These next generation anticoagulants were developed to replace warfarin, a type of rodenticide used for the past seven decades to treat patients at risk for deep-vein thrombosis and embolism. Although comparable to warfarin in efficacy with far fewer interactions and less need for monitoring, there is no antidote to stop severe bleeding. A San Francisco biotech firm has been developing such an antidote, known as AndexXa, but this drug has yet to gain FDA approval.

Meanwhile, in the wake of allegations by plaintiffs that the recommended dosage of Xarelto (15 – 20 mg) was too high, Janssen and Bayer have submitted a New Drug Application to the FDA for a lower dose version of Xarelto. The federal regulatory agency currently has the application under “priority review.”