Xarelto vs Pradaxa

Xarelto, Bayer’s latest blood thinning medication, has brought in billion of dollars in profit and continues to be prescribed by physicians to prevent blood clots and to protect from strokes. However, the drug can cause irreversible internal bleeding that can quickly lead to death. Lawsuits have been filed against Bayer claiming that the company knew about the dangers with Xarelto and failed to properly warn the public. Those that have been affected by Xarelto want the drug taken off the market immediately.

 

What is Xarelto?

Xarelto (rivaroxaban) is one of the latest anti-coagulation, or blood thinning, medications approved for use by the FDA. The drug is an oral medication developed by Bayer and Johnson & Johnson. Blood thinning medication works by preventing dangerous blood clots that can move throughout the body and cause an obstruction of blood flow to the vital organs. The older anti-coagulation medications require a physician to prescribe a precise dose for each patient leading to extensive monitoring. Xarelto is a new type of anti-coagulant that is prescribed in one uniform dose making it an attractive alternative for both patients and doctors.

The Food and Drug Administration (FDA) approved Xarelto to reduce the risk of strokes in patient’s suffering from AF and to reduce the risk of blood clots in patients that have recently had hip or knee surgery. The FDA continued to approve Xarelto for treatment of deep vein thrombosis (DVT) and pulmonary embolisms (PE).

One of the most deadly side effects when using Xarelto is uncontrolled bleeding. When internal bleeding occurs near a major organ, the blood flow to that organ becomes blocked and can cause severe damage to the organs ability to function. Internal bleeding can also cause pools of blood to form throughout the body causing a multitude serious health risks. Xarelto is an anticoagulant meaning it prevents blood from clotting. Bleeding will continue to occur and cannot be stopped until the drug has been entirely eliminated out of the body.

 

Pradaxa vs. Xarelto

Another blood thinner drug is dabigatran, manufactured by Boehringer-Ingelheim with the commercial name Pradaxa. This medication is used for the therapy of the same conditions that Xarelto treats, but its mechanism of action is slightly different. Xarelto stops the enzyme Factor Xa from helping the formation of thrombin, another protein involved in the formation of blood clots. Pradaxa, on the other hand, directly stops the production of thrombin without affecting Factor Xa.

The actual market of the blood thinners has and an estimated value of roughly $10 billion, although just a few drugmakers he with only a few companies manufacturing these drugs. In the last few decades, Warfarin completely dominated this scenario, although this old anticoagulant required patients to follow strict dietary restrictions as well as frequent blood tests in appropriate clinics. Since that drug was deemed “complicated” to use, the Big Pharma invested a lot of money in the development of simpler, more convenient medications such as Pradaxa and Xarelto. In order to recover from the substantial investments, pharmaceutical companies are asking a steep price to be paid to buy the newer drugs, though. Xarelto’s price is about $3,000 for a yearly treatment, compared to just $200 for one year of therapy with Warfarin.

 

The Clinical Trials and Xarelto’s approval

Xarelto was originally approved by the FDA for use as a blood thinner in patients recovering from hip replacement or knee surgery. The FDA continued to approve the drug for blood clots in patients with atrial fibrillation although their own panel disapproved of the use.

In 2011, the drugmakers funded a study that was later published in the New England Journal of Medicine. The ROCKET-AF clinical triad made a direct comparison between Warfarin and Xarelto in patients suffering from atrial fibrillation. According to the FDA, however, the trial did not demonstrate that new drug was safer or more effective than its counterpart that was marketed for more than five decades. Rivaroxaban was also associated with many more gastrointestinal bleeding accidents. Among the most threatening side effects of Xarelto, uncontrolled bleeding can be impossible to treat, and neither Bayer nor Janssen Pharmaceutical ever released adequate information on how to stop this kind of problem once it occurs. The numbers of patients who lose their lives in the emergency room keeps rising every day.

Other adverse reactions linked to rivaroxaban reported by the FDA include even a heightened risk for blood clotting. Some international agencies indicated that this risk may be even higher in patients who underwent joint replacement surgeries. The thrombi can migrate to the brain or heart causing a stroke or an infarction. Xarelto is also dangerous for patients who receive spinal anesthesia because the formation of an hematoma can lead to paralysis. The risk of spine hemorrhages is even higher than in patients under treatment with non-steroidal anti-inflammatory drugs (NSAIDs).

 

The risk of surgical complications and wound infections

Patients who underwent orthopedic surgery interventions such as the removal of a knee or hip prosthetic implant, suffered from additional side effects when treated with rivaroxaban. A research published in the Journal of Bone and Joint Surgery showed that among 13,000 patients treated the NOAC, many of them had to take many antibiotics to fight off serious wound infections. Leakage was also four times more frequent than in subjects treated with heparins, and the chance of reoperation within 30 days was significantly higher. Many physicians preferred to prescribe Tinzaparin, an older blood thinner, to avoid these complications. NOACs such as Pradaxa and Xarelto are contraindicated during breastfeeding and pregnancy, and in patients affected by renal conditions.

Article written by Dr. Claudio Butticè, Pharm.D.

 

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