CORRECTED: Cheap blood drug "could save 100,000 lives a year"

(Corrects figure in paragraph 12 to 20,000)

By Kate Kelland, Health and Science Correspondent

LONDON (Reuters) - A cheap and easily administered medicine that helps to stem excessive bleeding could save the lives of many thousands of accident victims across the world, British scientists said on Tuesday.

Researchers studied 20,000 patients across 40 countries and found that the drug -- tranexamic acid, or TXA -- significantly cut death rates, suggesting it could prevent up to 100,000 untimely deaths a year worldwide if it were used routinely.

The drug, which is an off-patent generic medicine made by several companies and costing around $4.50 per gram, should also now be listed as "essential" by the World Health Organization (WHO), the researchers said.

"The option to use tranexamic acid should be available to doctors treating trauma patients in all countries," said Ian Roberts and Haleema Shakur of the London School of Hygiene and Tropical Medicine, whose study was published in The Lancet.

Based on their findings, TXA could save about 13,000 lives each year in India and about 12,000 in China, they said. It would also save around 2,000 in the U.S. and more in Europe.

Injuries are a major cause of death worldwide. Every year, more than a million people die from road injuries and traffic accidents are the ninth leading cause of death worldwide.

On top of that, stabbings, shootings, land mines and other injuries kill thousands more, many of them young men.

Hemorrhage, or excessive bleeding, is responsible for about a third of trauma deaths in hospitals and can also contribute to deaths from multi-organ failure.

"Each year about 600,000 injured patients bleed to death worldwide," said Roberts. "It's important to remember that deaths from injuries are increasing around the world and that they usually involve young adults, often the main breadwinner in the family. The impact on the family is devastating."

More than 90 percent of trauma deaths occur in low-income and middle-income countries, where access to medicines is often restricted by poorer infrastructure and fewer resources.

Since TXA helps to stem bleeding by reducing clot breakdown, Roberts's team thought it might work well for patients with severe bleeding. However, they were worried it might increase the risk of blood clotting complications such as heart attacks, strokes and clots in the lungs.

Their large trial involved 20,000 severely injured adults who had significant bleeding, or were at risk of significant bleeding, and were within a few hours of having been injured.

Patients received either one gram of TXA by injection, followed by another one gram in a drip over the following eight hours, or a matching placebo or "dummy" medicine.

The researchers then studied the numbers of deaths in hospital within four weeks of injury and found that TXA cut the risk of death due to excessive bleeding by about one sixth, and there was no increased risk of clotting complications.

Etienne Krug, the WHO's director for violence, injury prevention and disability, said the findings were important and could help to lessen the impact of accidents and injuries.

"Across the world, injuries kill more than five million people each year and leave millions more permanently disabled. The economic and social cost of injury is enormous, with most of the burden in low- and middle-income countries," he said.

"It is essential that doctors are aware of these results and take them into account in the emergency management of seriously injured patients."

(Editing by David Stamp)