Nov. 14 (Bloomberg) -- Doctors may someday slow or reverse the aging process with drugs that stimulate the body to repair itself as a result of research undertaken by Pfizer Inc.

Pfizer, the world's largest drugmaker, will spend $100 million during the next five years to harness stem cells to treat heart disease, diabetes and vision loss common among the elderly, said Ruth McKernan, the scientist heading the program.

Stem-cell technology has primarily been the province of small biotechnology companies, such as Geron Corp. of Menlo Park, California and closely held Novocell Inc. of San Diego. Now scientists from Pfizer, working in labs in Cambridge, Massachusetts, and Cambridge, England, will research new treatments to spur stem cells already in people's bodies to become active in healing,

``The major pharma companies are moving into the field and taking a very strong position,'' said Alan Trounson, president of the California Institute of Regenerative Medicine, the state agency that funds stem-cell research. ``We feel they're like big ships coming together with us. It's starting to be an armada.''

Pfizer, based in New York, fell 45 cents, or 2.7 percent, to $16.28 at 4:15 p.m. in New York Stock Exchange composite trading. The company has lost 28 percent this year.

The drugmaker today announced details about its U.K. lab, where therapies will be researched for vision and hearing, said Corey Goodman, president of Pfizer's biotherapeutics and bio- innovation center, in a telephone interview yesterday. The U.S. team will focus on heart disease, cancer and diabetes. Pfizer is hiring 70 scientists by the end of next year to staff the laboratories.

Embryonic Cells

Pfizer will work with both embryonic stem cells, derived from days-old embryos, and adult stem cells, found in the mature tissue of living beings. Embryonic cells have the potential to form any of the roughly 210 cell types in the human body while adult cells have a more limited ability to form cells found in or around their organ or origin.

Other drugmakers are also interested in the technology. London-based GlaxoSmithKline Plc, the world's second-biggest pharmaceutical company; Johnson & Johnson, of New Brunswick, New Jersey; and Swiss drugmakers Novartis AG and Roche Holding AG all have begun partnerships or invested in companies developing stem- cell treatments.

On July 24, Glaxo announced a four-year, $25 million deal with Harvard University in Cambridge, Massachusetts, to explore the technology. J&J's venture-capital arm took an equity stake in Tengion Inc. of East Norriton, Pennsylvania, which is making bladders and other organs in the lab, and led a $25 million round of funding last year for Novocell, which is using embryonic cells to develop diabetes therapies.

Last year, the venture funds of Novartis and Roche helped bankroll a 3-year-old Spanish company, Cellerix, now testing stem cells from patients' own fat to treat rare skin conditions.

`Industry Ripening'

``The industry is getting riper,'' said Reinhard Ambros, executive director of the Novartis Venture fund, which invests in life-science companies. ``There will be more companies coming with good technologies that will raise more interest from VC people.''

Pfizer, though, is the first large pharmaceutical company to have a ``dedicated program,'' said John McNeish, the Pfizer scientist who will head the Massachusetts effort. The company's initiative required a change in corporate policy on stem cells and approval by Chief Executive Officer Jeffrey Kindler and the board, Goodman said.

Pfizer's approach is based partly on the work of Sheng Ding, a stem-cell scientist at Scripps Research Institute in La Jolla, California.

``People might not know that stem cells are everywhere in the body and play a role in disease,'' Ding said in an e-mail. ``Awakening stem cells already present in the body might be very attractive for therapeutic intervention to achieve healing and repair.''

Fate Therapeutics

Last year, Ding helped found Fate Therapeutics, based in San Diego. Both Fate and Pfizer will look for drugs that can trigger nascent stem cells in the heart or other organs to help repair damage caused by disease.

With experience, scientists will eventually find ways to infuse cells directly into patients' bodies to repair diseased organs. McNeish said.

``Most people and scientists do believe that cells will be medicines in the near future,'' he said. ``Embryonic stem cells offer the only way you're going to get to some diseases, like diabetes and neurological diseases.''

James Thomson, of the University of Wisconsin in Madison, first isolated stem cells from human embryos in 1998 and showed they had almost unlimited ability to become other cell types.

Time Line

``Originally, pharma stayed away because of the time line, knowing that stem cell-based therapies will be years down the road,'' said Brock Reeve, executive director of the Harvard Stem Cell Institute. ``Where things have changed in the last year is that we can now create cells of interest in particular diseases'' by using new techniques, including a method to reprogram adult cells into the equivalent of embryonic cells.

Using that technique, pioneered by Kyoto University researcher Shinya Yamanaka, scientists can take skin from a person with a disease and genetically manipulate it to create ``induced pluripotent stem cells,'' or IPS cells.

Those can be made into neurons, muscle cells or heart cells and studied for clues to the workings of the disease and to see how they respond to drugs.

To contact the reporter on this story: Rob Waters in San Francisco at rwaters5@bloomberg.net.

Last Updated: November 14, 2008 16:34 EST