Mary Bowerman

USA TODAY

Change follows federal decision to %27retire%27 chimpanzees from involvement in lab studies

Study requested by Congress found that using chimps in research was unnecessary

Food and Drug Administration requires that experimental medications be tested on two animal species before being tried in humans

Merck & Co., the third biggest drug maker in the world, is the latest in a string of pharmaceutical companies to halt studies using chimpanzees.

Many pharmaceutical companies are adopting policies against chimp studies, partly because a 2011 study requested by Congress concluded that nearly all chimpanzee use in research was unnecessary. Last June, Congress and the National Institutes of Health began retiring 90% of government-owned chimps to sanctuaries.

Many companies are discontinuing chimp research after facing pressure from consumers and advocacy groups, combined with advances in technologies and alternatives to using animals, said Kathleen Conlee of the Humane Society of the United States..

"We want to protect the chimpanzees from further use and get them to sanctuaries," Conlee said.

But she said Merck's decision does not affect 442 chimps owned by private companies for research. "The work isn't done."

Merck & Co., based in Whitehouse Station, N.J., is best known as the maker of household products such as Claritin, Coppertone and Dr. Scholl's as well as vaccines and other prescriptions.

Merck decided to discontinue testing on chimps late last year, the company said in a statement. "As the science evolved, it became clear testing was no longer necessary," the company said.

Dr. John Pippins, of the Physicians Committee for Responsible Medicine, said the turn away from chimpanzees foreshadows the end of other research involving animals.

"It is going to be hard for a researcher to say it is necessary to use animals, when our closest relative, sharing 98% of our DNA, was deemed unnecessary in studies," Pippins said. "How do you say, 'Well we can use another animal that shares only 50% of our DNA'? It doesn't work."

Five chimp laboratories operate in the USA; three are associated with universities. The largest is the New Iberia Research Center at the University of Louisiana in Lafayette, Conlee said.

She said the Humane Society hopes that less demand from the private sector for chimps used in research will encourage the remaining labs to release their chimps to sanctuaries.

Josh Bloom of the American Council on Science and Health, a non-profit consumer health and advocacy organization, said the decline in chimp studies is also based on cost.

"The cost has become prohibitive," said Bloom who has a doctorate in chemistry and experience on drug research studies. Bloom said that chimpanzees can live longer than humans so the care of the animal goes on long after the study is over.

Animals have been used in testing of consumer products for years. The Food and Drug Administration requires experimental medications be tested on two species of animals before they can be used in humans. Typically, animals such as mice, rabbits, cats, dogs, and non-human primates are used.

With technological advances such as computer simulations and the possible expanded use of stem cells Pippins said there increasingly are research methods that relate directly to humans.

According to Conlee the government will reassess the need for the remaining chimps in the next five years, but for now the Humane Society sees this as a win.

"Merck [& Co.] was one of the biggest players in chimp studies," Conlee said. "It sends a message that it's time to work on retiring these animals."