Discomfort from sore, inflamed joints may someday cease to plague the 2.1 million Americans who suffer from rheumatoid arthritis, if an oral treatment for the condition developed by scientists at the Medical School and Beth Israel Hospital pans out.

According to a study published last week in Science, a solution extracted in part from chicken bones appears to halt the progression of the disease by "teaching" the body's immune system to stop the inflammatory responses which characterize rheumatoid arthritis.

But Dr. David E. Trentham, associate professor of medicine at the Medical School and one of the physicians who developed the treatment, said the drug must be tested more vigorously before it can be approved and distributed to patients.

Dr. Arthur I. Grayzel '53, senior vice president for medical affairs at the Atlanta-based Arthritis Foundation, estimated that under the best circumstances, the drug will not be on the market for three years.

Both Trentham and Grayzel warned arthritis patients against over-the-counter drugs based on collagen, the major constituent of the treatment. Although such drugs are available at pharmacies, they do not have the proper amount of collagen, a protein found in joint cartilage, and have not been tested clinically.

Autoimmune diseases, such as arthritis and AIDS, are caused by the body's mistaken attacks on its own systems. In rheumatoid arthritis sufferers, the body's immune system causes swelling of joint linings. This inflammation damages bone and cartilage and can result in pain, loss of movement and eventual destruction of the joint.

Trentham, a physician in Beth Israel Hospital's rheumatology department, said the solution reduces inflammation through a process called "oral toleration."

According to Grayzel, this approach to combating arthritis is particularly exciting. Feeding patients with a drug as opposed to injecting them, he said, is a novel approach which elicits a "profound immune response." The method, according to Grayzel, produced favorable results in laboratory studies on multiple sclerosis-afflicted patients conducted during the past year.

An oral technique is also beneficial in that it arrests immune response before the onset of arthritis, effectively nipping the disease in the bud. A third advantage of the collagen solution is that it has shown low levels of toxicity in studies to date.

In the hopes of "reinstructing" the immune system to cease attacking joints, researchers administered Type II collagen to 60 rheumatoid arthritic patients who had not responded favorably to treatment.

After about three months, both subjective and objective tests yielded data which suggested that the patients who received the collagen had benefited from the drug.

"We found within the collagen-treated group there was significant improvement," Trentham said.

Data showed that patients treated with the collagen improved, and most of those on the "control" drug deteriorated.

"It looks as if something safe which is taken by mouth and gets to the heart of the disease seems to be effective," Grayzel said. "People are very interested in seeing what the next phase of the study shows."