golden retriever
Anti-ageing drug to be trialled on larger dogs over next few years (Calyponte/Creative Commons)

An anti-ageing drug is to be given to pet dogs to see if it will extend their lives, researchers have announced.

A team from the University of Washington in Seattle is planning to test rapamycin on dogs in order to gain a better understanding of how it would work on humans, and what side-effects might be expected.

According to Nature magazine, various drugs have been used to extend the lives of yeast, worms and mice. However, the results have never been replicated in human trials.

Rapamycin is used in humans as an anti-rejection drug following kidney transplants. It has been found to extend the life of mice by about 11% and is involved in cell growth. Some researchers believe it could slow the ageing process, while others say it might prevent age-related diseases.

However, the drug is no longer patentable so few companies would be willing to invest in it as an anti-ageing compound. Human trials are also extremely expensive and to test if it extends a person's lifespan would take a very long time.

To test its anti-ageing properties, the University of Washington researchers plan to give low doses of rapamycin to large dogs that normally live between eight and 10 years. Of the 30 animals involved, half would be given the drug.

Researchers say the trial could take as little as three years and they would be able to establish the effects on heart function, side effects and other aspects of health.

Molecular biologists Matthew Kaeberlein and Daniel Promislow, who will be running the study, have so far collected $200,000 (£124,000) in funding for the study, but they say they will need more for a larger trial involving several hundred dogs following the initial tests.

The scientists invited canine experts and biologists to a meeting in Seattle to discuss how to structure the pilot.

Physiological geneticist David Harrison of the Jackson Laboratory in Maine, who has previously studied rapamycin, said the study looks promising: "We're talking about whether aged pets will benefit, and that's a good model for a human population."