RX : NEW DRUGS OFFER HOPE FOR ARTHRITIS SUFFERERS.

Byline: Denise Mann Medical Tribune News Service

Three up-and-coming genetically engineered drugs may alleviate - or end - the severe joint pain, swelling and stiffness of people who suffer from rheumatoid arthritis, according to a report presented here at the annual meeting of the American College of Rheumatology.

The drugs - the first freshmen in an all-new class of medications called biological response markers - act by attacking various factors that cause rheumatoid arthritis, as well as its often crippling symptoms, according to three new studies presented.

In rheumatoid arthritis, the joints swell, causing pain and inflammation. The new drugs interfere with this process, the researchers reported.

More than 2 million Americans, mostly women, suffer from rheumatoid arthritis, a disease marked by pain, stiffness, swelling and loss of function in the joints.

Given by injection, the new genetically engineered drugs do not appear to have any side effects except for a rash at the injection site, according to three preliminary studies of more than 700 people.

``These studies are still in progress, but we are very excited because it is a new way of addressing the treatment of rheumatoid arthritis,'' said Dr. Arthur Weaver, president of the American College of Rheumatology and a clinical professor of internal medicine at the University of Nebraska Medical Center in Lincoln.

``The new drugs have excellent results in a relatively short period of time and their safety record is outstanding so far,'' he added.

``All the people in the new studies had severe rheumatoid arthritis, but the potential for these drugs is really high, and if they are proven safe, these drugs will be able to be used earlier and earlier in people with this disease, possibly stopping joint destruction before it starts,'' said Dr. Edward Harris Jr., professor of medicine at Stanford University in Palo Alto, Calif. and director of the musculoskeletal disease center at Stanford.

One of the promising new drugs is a genetically engineered copy of a human protein that provides relief from rheumatoid arthritis by blocking cells of the body's immune system - interleukin-1 cells - from causing inflammation. This drug, known as recombinant human interleukin-1 receptor antagonist, is being developed by Amgen Inc., a biotechnology pharmaceutical company in Thousand Oaks, Calif.

In a study of 472 people in 11 countries, in the group given the highest dose, about 43 percent of those who received daily injections of the drug for six months had fewer swollen joints and less pain within two weeks after beginning treatment than those given placebo.

``And people taking this drug were less likely to develop any new joint damage during treatment, and showed a slowing down of destruction in their already damaged joints,'' said lead study author Dr. Barry Bresnihan, a professor of rheumatology at the University College of Dublin in Ireland.

``In subtle ways, people were able to do more things such as dressing themselves and becoming more comfortable in their daily routines,'' Bresnihan said.

Another drug on the horizon, under development by Immunex Corp. in Seattle, is called tumor necrosis factor receptor.

This drug works by halting one of the body's mechanisms that drives joint inflammation - tumor necrosis factor (TNF). TNF helps stimulate the body's interleukin-1 cells to aggravate joints, according to Dr. Scott Baumgartner of the Physicians Clinic of Spokane in Spokane, Wash.

A third new drug targets the immune system's T-cells, which become overactive in people with rheumatoid arthritis. Overactive T-cells help motivate the immune system to attack joints and destroy healthy tissue.

In a clinical trial, the higher the dose of the drug, the greater the reduction in affected joints and pain.