Dabigatran, New Blood Thinner Linked To Higher Heart Attack Risk

In continuation of my update on Dabigatran...

Researchers lead by Dr.Ken Uchino from the Cleveland Clinic in Ohio looked at seven trials involving Pradaxa (Dabigatran) that included more than 30,000 patients. This process, called a meta-analysis, uses data from published clinical trials to tease out a pattern that might not show up in a single study. Researchers found Pradaxa was associated with an increased risk of heart attack or acute coronary syndrome (heart attack or angina), compared with two other commonly used blood thinners, warfarin (Coumadin, Jantoven) and enoxaparin (Lovenox).

As per the claim by the researchers,  those taking Pradaxa, 1.19 percent had a heart attack or suffered from acute coronary syndrome compared with 0.79 percent of those taking either of the other drugs, they noted. Although there was a 33 percent increase in relative risk for a heart attack among those taking Pradaxa, the absolute increased risk -- that is, the added risk for any one individual of having a heart attack if on Pradaxa -- was 0.27 percent, researchers said.

Pradaxa was approved by the U.S. Food and Drug Administration in October 2010 for people with a common heart rhythm problem called atrial fibrillation. People with atrial fibrillation are at a higher risk for stroke and are often prescribed medication to prevent clotting....

Ref : http://my.clevelandclinic.org/cerebrovascular_center/medical_professionals/clinical_trials.aspx

New oral blood thinners can decrease stroke risk in atrial fibrillation patients without frequent monitoring

In continuation of my update on dabigatran (Pradaxa), rivaroxaban (Xarelto), apixaban (Eliquis) and edoxaban (Savaysa).

A new generation of blood thinners can reduce the risk of stroke in patients with atrial fibrillation, without requiring frequent monitoring and dietary restrictions.

But special attention must be given to the patient's age, kidney function and other factors before prescribing the new medications, according to a review article by neurologists at Loyola Medicine and Loyola University Chicago Stritch School of Medicine.

The report by Rochelle Sweis, DO and José Biller, MD, is published in the journal Current Treatment Options in Cardiovascular Medicine.

Atrial fibrillation (AFib) is the most common type of irregular heartbeat, and the prevalence is increasing as the population ages. In AFib, electrical signals that regulate the heartbeat become erratic. Instead of beating regularly, the upper chambers of the heart quiver and blood doesn't flow well. Blood clots can form, migrate to the brain and cause strokes. AFib is associated with a fivefold increase in the risk of stroke.

Blood thinning medications decrease the stroke risk by approximately 70 percent. For 60 years physicians have prescribed warfarin (Coumadin) and other blood thinners known as vitamin K antagonists. These medications have been proven to be effective in reducing the risk of blood clots and strokes. But they require continual monitoring and dose adjustments to ensure the drugs thin the blood enough to prevent clots, but not enough to increase the risk of major bleeding. Patients also must restrict their consumption of foods rich in vitamin K, such as spinach, Brussels sprouts, kale, parsley and green tea.

 

Warfarin

The new blood thinners include dabigatran (Pradaxa), rivaroxaban (Xarelto), apixaban (Eliquis) and edoxaban (Savaysa). In the right patient population, the new drugs are a safe and effective option for treating atrial fibrillation, Drs. Sweis and Biller write.

Dabigatran         Rivaroxaban (BAY 59-7939)

Apixaban Edoxaban

New oral blood thinners can decrease stroke risk in atrial fibrillation patients without frequent monitoring: A new generation of blood thinners can reduce the risk of stroke in patients with atrial fibrillation, without requiring frequent monitoring and dietary restrictions.

FDA approves Pradaxa to prevent stroke in people with atrial fibrillation....

We knew that, Dabigatran (see structure, Pradaxa in Europe and USA, Pradax in Canada) is an anticoagulant from the class of the direct thrombin inhibitors. It is being studied for various clinical indications and in many cases it offers an alternative to warfarin as the preferred orally administered blood thinner since it does not require prothrombin time monitoring while offering similar results in terms of efficacy. It was developed by the pharmaceutical company Boehringer Ingelheim. Though it was approved in Europe in 2008, now FDA has approved the drug in October 2010 for the prevention of stroke and blood clots in patients with abnormal heart rhythm (atrial fibrillation).

Pradaxa is an anticoagulant that acts by inhibiting thrombin, an enzyme in the blood that is involved in blood clotting. The safety and efficacy of Pradaxa were studied in a clinical trial comparing Pradaxa with the anticoagulant warfarin. In the trial, patients taking Pradaxa had fewer strokes than those who took warfarin.

 "Unlike warfarin, which requires patients to undergo periodic monitoring with blood tests, such monitoring is not necessary for Pradaxa," Dr. Norman Stockbridge(director of the Division of Cardiovascular and Renal Products in the FDA's ) says.

Pradaxa, manufactured by Boehringer Ingelheim Pharmaceuticals Inc. of Ridgefield, Conn., will be available in 75 milligram and 150 milligram capsules....

Ref : http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm230241.htm

Dabigatran etexilate a better drug than warfarin for VTE?.

We know that Dabigatran is an anticoagulant from the class of the direct thrombin inhibitors. It is being studied for various clinical indications and may replace warfarin as the preferred anticoagulant in many cases. It is orally administered as the prodrug dabigatran etexilate (marketed as Pradaxa since April 2008 in European countries and Pradax in Canada). It was developed by the pharmaceutical company Boehringer Ingelheim.

Now researchers lead by  Dr. Sam Schulman, a professor of medicine of the Michael G. DeGroote School of Medicine (McMaster University), who conducted a randomized, double-blind trial of 2,539 patients with acute VTE (venous thromboembolism) have found that dabigatran (see structure) is a safe and effective anticoagulant that does not require the routine monitoring or dose adjustments that are necessary with warfarin. In other words, patients can receive the same results in a more convenient manner. 

As per the claim by the researchers, the improvement seen in both groups from the treatments was similar. After six months of treatment, only 2.4 percent of the dabigatran etexilate group (30 patients) and 2.1 percent of the warfarin group (27 patients) experienced recurrent VTE. The safety of the two drugs was also comparable. In the dabigatran etexilate arm, 205 patients experienced bleeding (including 20 patients with major bleeding) versus 277 patients in the warfarin arm (including 24 with major bleeding). Other possible side effects, including death, acute coronary syndromes, and abnormalities in liver function tests, were infrequent in the two groups. Hope patients suffering from VTE will now breathe a sigh of relief....

Ref : http://dailynews.mcmaster.ca/story.cfm?id=6511

Aspirin as Good a Clot Buster as Pricey Drugs After Joint Replacement

Good old aspirin is just as effective as newer, expensive drugs at preventing blood clots after hip or knee replacement, a new clinical trial suggests.

Researchers said the findings could change some doctors' prescribing habits.

After knee or hip replacement surgery, there's a risk of blood clots in the legs or lungs. So it's routine for patients to take clot-preventing drugs for some time afterward.

Right now, some doctors choose powerful anti-clotting drugs like dabigatran (Pradaxa) and rivaroxaban(Xarelto), said Dr. David Anderson, the lead researcher on the new trial.

But it hasn't been clear whether those expensive prescription drugs are any better than cheap, readily available aspirin, explained Anderson, of Dalhousie University, in Halifax, Canada.

Based on the new findings, they're not.

Few patients in the study developed a blood clot after surgery, and those on aspirin fared just as well as those on rivaroxaban.

The caveat, Anderson said, was that all study patients received rivaroxaban for the first five days after surgery. After that, they either continued on the drug or switched to aspirin for another nine to 30 days.

"From this study, we have no evidence to support starting aspirin on day one," Anderson said.

But after day five, he added, "it's very reasonable to consider switching to aspirin."

Over the past decade, surgeons have already been turning away from powerful anticoagulants toward aspirin and non-drug options for thwarting clots, said Dr. Alejandro Gonzalez Della Valle.

Gonzalez Della Valle specializes in hip and knee surgery at the Hospital for Special Surgery in New York City.

These days, he said, patients have a generally low risk of blood clots after hip or knee replacement for a number of reasons. Those include shorter surgical times, and the use of regional anesthesia instead of general.

Clots can also be prevented by improving blood flow in patients' legs right after surgery. So getting patients on their feet and moving early on is key, Gonzalez Della Valle explained. Similarly, pneumatic compression devices can be used to encourage blood flow in the lower limbs while patients are in their hospital beds.

Dr. Kevin Bozic, a spokesperson for the American Academy of Orthopaedic Surgeons (AAOS), said that the AAOS guidelines already state that no one drug is better than another for preventing clots.

"This study reinforces that," Bozic said.

He agreed that most surgeons have been turning to aspirin in the past 10 years because recovery times are shorter and people leave the hospital much sooner. Most people can have just aspirin, but some at high risk of blood clots -- those with a history of clots, people who are very obese -- might need an anticoagulant, Bozic added.

"The strategy for preventing clots should include medication and early mobilization," he stressed.

Ref:http://www.nejm.org/doi/full/10.1056/NEJMoa1712746

Aspirin as Good a Clot Buster as Pricey Drugs After Joint Replacement - Drugs.com MedNews