Future Approaches to Arthritis Treatment

The Arthritis Sourcebook Research on treatment of various types of arthritis is underway, focusing on gene therapy, vaccines, and biologic response modifiers.Gene therapy is a treatment for diseases that have a genetic link -- a defective gene exists that makes some persons susceptible to a disease. A healthy gene is injected into those persons known to have the predisposing gene marker. This may work in some persons with early signs of certain types of arthritis. Much research remains to be done. It is thought that diseases which may respond best to gene therapy are rare ones like osteogenesis imperfecta.

Vaccines are being investigated because some forms of arthritis, particularly RA, are thought to be triggered by a virus or bacterium in persons with a predisposition for the disease. If researchers can identify what the triggering mechanism is, they may be able to develop a vaccine for treatment.

A clinical trial on minocycline in rheumatoid arthritis (MIRA) was conducted in six research centers in the United States. Minocycline is an antibiotic drug in the tetracycline family that reduces joint swelling and tenderness in persons with mild to moderate RA. Study participants showed a 50 percent or greater improvement in the number of swollen and tender joints. Researchers are not certain why or how minocycline works. It is an antibiotic, but it may also work to inhibit enzymes that contribute to the destruction of bone and cartilage. It may also work by reducing inflammation. Additional research needs to be conducted to determine exactly how minocycline acts.

Biologic response modifiers are also being studied. These are proteins, which can be isolated and synthetically produced in the laboratory, that regulate parts of the chemical reactions in the body resulting in inflammation. Researchers want to determine how this process takes place and how to stop it at various locations in the body.

Tumor necrosis factor (TNF) is currently the most frequently studied protein. It is a key messenger in the body's chemical reaction that leads to inflammation. TNF is a cytokine, which is a family of inflammation-causing substances. TNF antagonists, also proteins, counteract the effects of TNF, thus reducing RA symptoms. A TNF antagonist (TNF receptor TNFR:Fc) now being studied has produced significant improvement in physical disease symptoms, laboratory tests, physician and patients' own assessments of their condition, and overall quality of life in patients participating in clinical trials.

Collagen, an important protein in the manufacture of skin, bone, and joints, taken orally has also been shown to reduce inflammation in persons with severe RA. Researchers used Type II collagen, a major component in joint cartilage, in a clinical trial of persons with severe RA. Participants showed a decrease in swollen and tender joints and had no side effects. Researchers think that Type II collagen taken orally may work by turning off cells involved in causing inflammation and may fool the immune system into not responding with inflammation.