New drug 'spectacular' at preventing strokes: study

From the Montreal Gazette:
For the first time since the blood thinner warfarin was introduced more than half a century ago, Canadian researchers are reporting that a new drug is safer and more effective at reducing the risk of stroke in high-risk patients.

An estimated 250,000 Canadians suffer from atrial fibrillation, or AF, a potentially life-threatening heart rhythm disorder that causes the heart to quiver and beat chaotically. Blood can pool in the upper chambers of the heart, allowing clots to form and travel up to the arteries that feed the brain, creating a stroke. AF patients are at five times greater risk of developing stroke, and twice as likely to die from one, than patients without the condition.

The disorder affects about three per cent of the population over age 45, and about six per cent over age 65, according to the Heart and Stroke Foundation.

Warfarin has been the drug of choice for reducing stroke risk in atrial fibrillation for more than 20 years. But it increases the risk of major bleeding, sometimes into the brain. About half the patients who might benefit can't take it, "and when they do try and take it, they often end up having to stop it for a variety of reasons," says Dr. Stuart Connolly, a professor of medicine at McMaster University in Hamilton. ...more

Automated calls help patients taking blood thinners

From CBC News:
Hearing a human say blood-thinner doses are correct may be reassuring, but an automated system can be equally effective for some, a new study suggests.

In Monday's online issue of the Canadian Medical Association Journal, researchers concluded that an automated voice response system reduced the workload by 33 per cent and was almost as effective as a phone call from a human.

About five per cent of seniors take oral anticoagulants such as warfarin for blood clotting disorders. Patients need to take regular blood tests to make sure they're taking the right dose — too little doesn't work, and too much can cause serious bleeding problems including a deadly form of stroke.

The dose has to be individualized and monitored closely, said study author Dr. Alan Forster, a patient safety expert with the Ottawa Hospital Research Institute and the University of Ottawa.

The study was designed to test whether computer algorithms can predict the right dose better than a human.

"The interactive voice response system was effective in communicating complex information as 77.8 per cent of messages were successfully delivered and did not require input from staff," Forster and his coauthors wrote. ...more

it's in the blood: the story of vitamin k

From the Montreal Gazette:
The chickens were hemorrhaging but Henrik Dam, a young biochemist at the University of Copenhagen couldn't figure out why.

The year was 1929 and Dam was investigating the metabolism of cholesterol in chickens. Eggs contained cholesterol but where was it coming from? The birds' diet?

To check this out, Dam extracted the cholesterol from the chicken feed and saw they still produced eggs with cholesterol. Obviously the birds were synthesizing the substance from other dietary components. But they were also bleeding in an unusual fashion. Adding cholesterol back to the chicks' diet didn't solve the problem. It therefore seemed that the cholesterol extraction removed some other substance of importance from the feed.

Dam eventually found that a second fat-soluble compound had indeed been extracted and it was its absence from the birds' diet that prevented blood from clotting. He called it the coagulation vitamin, or in German, Koagulationsvitamin. We now know it as vitamin K. ...more

Optimal Warfarin Dosing Improves Anticoagulation Control

From the Washington Post:
While the anticoagulant warfarin can be highly effective in preventing strokes and treating venous thromboembolism, doctors have long struggled with finding the best way manage the drug therapy.

Boston University School of Medicine (BUSM) researchers now claim to have figured out the optimal dosing levels to help patients, according to a study published in December online issue of the Journal of Thrombosis and Haemostasis.

The research team analyzed warfarin use in almost 4,000 patients to determine what are the most effective levels of the drug in a patient's system under different circumstances.

"The study suggests that anticoagulation control could be improved considerably by changing the warfarin dose only when the ratio is 1.7 or lower/3.3 or higher," lead author Dr. Adam Rose, an assistant professor of medicine at BUSM, said in a university news release. "In addition to offering warfarin to as many optimal candidates as possible, we also need to optimize warfarin dose management to fully realize the benefits of anticoagulation." ..more

New Remedies to Treat Blood Clots Are Near

From the Wall Street Journal:
Several big drug makers are in a neck-and-neck race to introduce new drugs for treating blood clots, which can lead to heart attacks and strokes, killing as many as a million people a year.

The prize is a chance at a piece of the blood-clot treatment market, which analysts estimate could be worth as much as €15 billion, or about $20 billion, by 2016.
[Treat Blood Clots]

Drugs currently used to prevent blood clots, also known as thrombosis, are effective and sell well but have problems. One popular treatment is difficult to dose and introduces risks when taken with other medicines and some foods. Another is an injectable, making long-term therapy difficult.

Five pharmaceutical companies are working on new treatments for blood clots. Three drugs -- developed by Bayer AG in partnerships with Johnson & Johnson, Boehringer Ingelheim GmbH, and Pfizer Inc. in partnership with Bristol Myers-Squibb Co. -- are now in the late phases of clinical testing.

The new drugs are taken by mouth, which makes them easier to use, their dosing is less troublesome, and they need no laboratory monitoring. They are also potentially more effective than existing treatments. The drug developed by Bayer and J&J has shown superior efficacy compared with standard therapy in a recent study. ...more

Warfarin underused by patients at risk for stroke

This study comes as no surprise to anyone who has worked in an anticoagulation clinic. There are far too many people in the community not being properly managed on their warfarin, or aren't taking it when they should be.

From Reuters:
New research indicates that most patients with atrial fibrillation -- the most common type of heart arrhythmia -- who suffered a stroke and were eligible for anticoagulation treatment, were not taking any warfarin or were not taking enough.

"These are missed opportunities for stroke prevention," lead author Dr. David J. Gladstone, from the University of Toronto, said in a statement. "Sadly, we frequently see patients admitted to a hospital with a devastating stroke who are known to have atrial fibrillation, yet were either not taking warfarin or were taking a dose that is not therapeutic."

Warfarin, also known by the trade name Coumadin, can reduce the risk of stroke by preventing the formation of blood clots, which often occur in patients with atrial fibrillation. The clot may detach from the wall of the blood vessel and become lodged in the brain, blocking the flow of blood and causing a stroke. Atrial fibrillation doesn't always cause symptoms, but the condition can be quite dangerous.

As they reported in the current online issue of Stroke, the researchers analyzed data for 597 patients with known atrial fibrillation and potentially preventable strokes who were entered in the Registry of the Canadian Stroke Network from 2003 to 2007....more

Doctors hopeful easier blood thinners are nearing

From the Associated Press:
A trio of experimental drugs has doctors hopeful that for the first time in decades, millions of people at risk of lethal blood clots may soon get easier treatment.

The first goal is a pill option for people who now need daily blood-thinning shots for weeks after knee or hip replacement surgery.

But the ultimate goal is an alternative to that old standby warfarin, also called Coumadin, the nation's most troublesome lifesaver because of side effects and restrictions its 2 million users face.

Now in late-stage testing in thousands of Americans are three pills that work to prevent blood clots in ways that promise to be less burdensome. One of the trio, Boehringer Ingelheim's Pradaxa, just began selling in Europe.

The drug research comes as Medicare is considering withholding payment from hospitals when at-risk patients develop clots in their veins, usually the legs — a common preventable cause of hospital deaths. The National Quality Forum has estimated that only about a third of patients who need protective blood thinners while hospitalized get them.

Known medically as a "deep vein thrombosis" or DVT, such a clot can kill quickly if it moves up to the lungs. There aren't good counts, but recent estimates suggest that about 900,000 people a year suffer a vein clot, and nearly 300,000 die. Being immobile for long periods, such as during hospitalizations or even long airplane flights, can trigger a clot. Vice President Cheney suffered one after a long trip last year. NBC correspondent David Bloom died of one in 2003 after spending days in a cramped military vehicle while covering the invasion of Iraq. ...more

New Thromboembolic Guidelines May Spark Controversy

From Medpage Today:
Most of the recommendations in the eighth edition of antithrombotic guidelines from the American College of Chest Physicians are only incrementally changed, but several are likely to be controversial, according to the authors.

The 2008 guidelines contain 179 new recommendations, as well as new chapters, to deal with areas of care that have seen significant development since the 2004 guidelines were issued, according to Jack Ansell, M.D., chief of medicine at Lennox Hill Hospital in New York and a member of the panel that developed the guidelines.

They are published as a 22-chapter supplement to the June issue of CHEST and are available online.

Dr. Ansell outlined several areas that are likely to be contentious. For instance, he said, "There has been a lot of buzz about the use of pharmacogenetics for drug dosing and warfarin (Coumadin) is one of the major candidates." ...more

Bayer plans largest-ever study for blood-clot drug

From Reuters:
Bayer is planning a late-stage study for its promising blood-clot drug rivaroxaban for hospitalised patients with internal diseases, the German drugs and chemicals group said on Tuesday.

"It is planned for a total of about 50,000 patients to take part in these studies, making it the largest clinical study programme Bayer has ever undertaken," Chief Executive Werner Wenning told reporters. Wenning said rivaroxaban, which the company wants to market under the trade name Xarelto, is the most promising product in its pipeline.

Rivaroxaban's current indications are prevention of venous thromboembolism, treatment of deep-vein thrombosis, stroke prevention in atrial fibrillation and acute coronary syndrome. ...more

Dutch stroke study urges greater anticoagulant use

From Reuters:
Dutch doctors called on Sunday for greater use of oral anticoagulants to prevent strokes in people with a common heart arrhythmia.

Atrial fibrillation (AF), a heart flutter, is dangerous because blood pools in the heart, forming clots that can lead to deadly strokes.

Current guidelines recommend that AF patients be treated with drugs to stop this happening, but many doctors are wary of using the anticoagulant pills because they are difficult to monitor and can lead to uncontrolled bleeding.

That physician caution may be costing lives, Ron Pisters and colleagues at the University Hospital Maastricht told the annual European Society of Cardiology congress. ...more

U.S. orders genetic data on blood-thinner risks

From Reuters:
Widely used blood thinner warfarin will come with new instructions explaining that people with certain genes may need a lower dose to take the drug safely, U.S. health officials said on Thursday.

The change is part of a move toward personalized medicine in which doctors tailor treatment based on genetic makeup, the Food and Drug Administration said.

Warfarin is sold by several generic makers and by Bristol-Myers Squibb under the brand name Coumadin. An estimated 2 million U.S. patients start taking the drug each year to prevent blood clots that may cause heart attacks and strokes.

Some patients, however, experience dangerous bleeding. Experts say about two in 100 patients taking warfarin will have a serious hemorrhage. Excessive bleeding from the drug is one of the most common prescription-related causes of emergency room visits, studies have shown. ...more

Genetic testing cited for blood thinner

From the Williston (NDak) Herald News Daily:
Federal health officials are stopping short of recommending genetic tests for patients on the blood-thinner warfarin, even though they have said such screenings could prevent thousands of complications each year.

"This means personalized medicine is no longer an abstract concept but has moved into the mainstream," the Food and Drug Administration‘s clinical pharmacology chief, Larry Lesko, said in announcing the label change.

The FDA has not changed its dosing recommendations for the drug, and tailoring the proper dosage remains largely a matter of trial and error.

Genetic testing can reveal which patients may require less of the drug and lead doctors to recommend doses closer to the lower end of the scale, FDA officials said. ...more

Cancer patients at risk for dangerous drug interactions: study

This article has a few good points, including some good advice for patients:

Ms. Kwong advises patients to:

—Always carry an up-to-date list of medications and their dosages, including over-the-counter and alternative therapies.

—Try to have prescriptions filled by the same pharmacy: electronic software will alert the druggist of potential drug interactions.

—Make sure to keep different doctors or pharmacists apprised of any changes in prescriptions.

Because of drug interactions, cancer patients can be challenging from a pharmacist perspective. However, solving these types of clinical puzzles can really show that the pharmacist is a drug information specialist.

From the Globe and Mail:
Many cancer patients are at risk for potentially dangerous drug interactions because of the number of different medications they take for multiple conditions, say Canadian researchers, who caution that steps must be taken to avoid these dicey combinations.

In a study appearing Wednesday in the Journal of the National Cancer Institute, researchers at Princess Margaret Hospital in Toronto found that almost 30 per cent of 405 cancer patients studied were taking drugs that put them at risk for at least one adverse drug interaction.

At least 9 per cent of the interactions could have had severe effects — including being potentially fatal — and 77 per cent were of moderate severity and could have resulted in serious health problems, the study showed. About 8 per cent of patients received duplicate medications. ...more

New clot drugs beckon as replacements for warfarin

From Reuters:
A new crop of medicines to prevent stroke and blood clots could emerge within several years, easing dangers and hardships for patients and creating blockbuster sales for drugmakers.

The oral drugs could prove better and safer than injectable medicines such as heparin now widely used to cut the risk of dangerous blood clots in the legs and lungs after major surgery.

But makers of the new drugs say their biggest use would be as an alternative to warfarin, a pill used for decades by people with atrial fibrillation -- or irregular heartbeat -- to prevent strokes. An estimated two million Americans have been diagnosed with the heartbeat problem and the number is expected to double in the next 20 years. ...more