Study: Doxycycline Plus Methotrexate Better for Treating Rheumatoid Arthritis

Doxycycline plus methotrexate as an initial treatment of rheumatoid arthritis is better than the drug methotrexate alone, according to a study presented this week at the American College of Rheumatology Annual Scientific Meeting in Orlando.

Methotrexate is a disease-modifying antirheumatic drug that is currently accepted as conventional initial therapy in treating rheumatoid arthritis. Belonging to the tetracycline family, the antibiotic doxycycline is used to treat bacterial infections such as pneumonia, lyme disease, acne, sexually transmitted diseases and anthrax. At lower doses, the drug is also used to treat gingivitis.

The researchers chose doxycycline over its tetracycline cousin minocycline as a potential treatment for rheumatoid arthritis because doxycycline cost about half as much.

The two-year trial involved 66 patients who had rheumatoid arthritis for less than one year and who had not previously been treated with disease-modifying antirheumatic drugs. The researchers compared the effectiveness of doxycycline at two different strengths plus methotrexate versus methotrexate alone.

Eighteen patients received a low dose of doxycycline plus methotrexate. Two other groups of 24 patients each received either a higher dose of doxycycline plus methotrexate or a placebo plus methotrexate.

The researchers found that 62.5 percent of patients receiving the higher dose of doxycycline plus methotrexate had significant improvement in their arthritis, compared to 38.8 percent of patients receiving low dose doxycycline and methotrexate and 33 percent of patients receiving methotrexate alone. Six patients taking doxycycline and two taking the placebo withdrew from the study due to adverse reactions.

"We showed that compared to conventional therapy, adding a fairly cheap drug gives patients a substantial benefit," said lead researcher Dr. James O'Dell, chief of Rheumatology at the University of Nebraska Medical Center, at an October 26 news conference.

"It gives us another option for the treatment of rheumatoid arthritis," O'Dell added, noting that doxycycline was "quite well tolerated" by the participants who took it.

O'Dell said the findings are particularly exciting for people with limited resources given the low cost of doxycycline. Compared to existing biological drugs, he observed that doxycycline is about 40 times cheaper.

Other source: American College of Rheumatology