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By Nancy Lapid

Jan 24 (Reuters) - Patients with a common heart rhythm

disorder who took an experimental blood-thinning drug had far

fewer bleeding episodes than patients receiving a

standard-of-care blood thinner, a new study has found.

A mid-stage trial testing abelacimab from Anthos

Therapeutics in patients with atrial fibrillation was stopped

early due to an overwhelming reduction in bleeding compared to

the rate seen in patients taking Johnson & Johnson's ( JNJ )

Xarelto, or rivaroxaban, researchers reported on Wednesday in

The New England Journal of Medicine.

Atrial fibrillation significantly raises stroke risks

because it can increase the likelihood that blood clots will

form in the heart that can travel to the brain. Many patients

refuse or discontinue anticoagulants, however, because the drugs

increase the risk of bleeding complications.

In the trial, 1,287 patients received either monthly

injections of 150 milligrams abelacimab, 90 mg abelacimab, or a

standard daily oral dose of rivaroxaban.

Abelacimab belongs to a new class of anticoagulants known as

Factor XI inhibitors that work by blocking a protein in blood

that plays a critical role in development of obstructive blood

clotting but is less involved in hemostasis, which is the body's

ability to prevent or control bleeding.

Over a median follow-up of roughly two years, the higher

dose of abelacimab reduced bleeding requiring hospitalization or

medical attention by 62% compared with rivaroxaban, while the

lower dose reduced those types of bleeding by 69%, the

researchers reported.

Gastrointestinal bleeding - the most common complication

with blood thinners - was reduced by 93% with abelacimab 150mg

compared with the J&J drug. Xarelto is a Factor Xa inhibitor

similar to Eliquis from Bristol Myers Squibb ( BMY ) and Pfizer ( PFE )

.

Earlier data from the same trial showed low rates of

bleeding during surgical procedures in patients fully

anticoagulated with abelacimab.

The trial was not designed to test the drug's effectiveness

at preventing strokes, however.

Abelacimab has received Fast Track designation from the U.S.

Food and Drug Administration for preventing clots associated

with atrial fibrillation and with cancer, the manufacturer has

said.

Other Factor XI drugs in development include MK-2060, being

tested by Merck & Co ( MRK ) for reduction of major thrombotic

cardiovascular events in patients with end-stage renal disease.

Bacteria may help prevent weight gain

Treatment with "good" bacteria may help people keep their

weight in check, experiments in mice suggest.

Animals injected weekly with Mycobacterium vaccae, a

microorganism found in cow's milk and soil, were essentially

immune to weight gain from a high-fat, high-sugar junk-food

diet, researchers reported in Brain, Behavior and Immunity.

"We saw a complete prevention of diet-related weight gain in

these animals," study leader Christopher Lowry of the University

of Colorado Boulder said in a statement.

"This suggests that exposure to beneficial bacteria can

protect us against some of the negative health outcomes of the

typical Western diet."

The researchers had previously found that M. vaccae can

prevent stress-induced inflammation and associated health

problems in mice.

When they subsequently attempted to learn whether the

bacteria could also help counter some of the brain inflammation

and anxiety that can result from a poor diet, they found not

only that it could, but that the organisms also prevented weight

gain.

The mice received either healthy food, junk food, or junk

food with weekly injections of M. vaccae. All groups received

about the same number of calories.

As expected, the untreated junk food group gained

significantly more weight than the healthy eaters. But to the

researchers' surprise, there was no difference in weight gain

between the junk food group that got injections of good bacteria

and the healthy eaters.

More research is needed to determine just how exposure to a

bacteria found in dirt could prevent weight gain, and whether it

can do so in people.

Add "prehab" to rehab for speedier surgery recovery

Recovery from surgery can be improved not just with

rehabilitation programs afterward but also with

"prehabilitation" beforehand, a review of clinical trial results

suggests.

Adults who actively prepared for major surgery by exercising

and improving their diet had fewer complications and shorter

hospital stays, according to researchers who analyzed data from

186 randomized, controlled studies involving a total of 15,684

participants.

After taking into account the type of surgery and patients'

individual risk factors, they found the risk of complications

was reduced by 50% with pre-surgery exercise, 38% with

pre-surgery nutritional support, and 36% with a combination of

exercise, nutritional, and psychosocial support, according to a

report published on Wednesday in The BMJ.

Compared with usual care, combined exercise and psychosocial

support was associated with 2.44 fewer days in hospital.

Individually and in combination, exercise and nutrition were

associated with roughly one less day in the hospital.

The researchers noted that the dependability of their

results is "generally low to very low" because of differences in

the ways the trials were conducted.

Still, they say, the results "were robust after excluding

trials with a high risk of bias, suggesting that prehabilitation

based on exercise, nutrition, or exercise combined with other

components, may benefit adults preparing for surgery."