STANFORD, Calif., March 31 (UPI) -- A new drug reduced the number of affected joints in patients with refractory rheumatoid arthritis that has lessening or no response to other treatments, according to an international clinical trial.
The drug, baricitinib, reduced the number of affected joints in about half the study's participants, offering a potential treatment for people with few options to ease the progressive condition.
Rheumatoid arthritis affects 1.5 percent of people in developed countries, causing pain stiffness, swelling and the destruction of small joints, such as in the hands and feet.
Although drugs have been effective in blocking immune mechanisms to reduce inflammation, many patients find the drugs lose their efficacy, carry significant side effects or both.
Regardless of participants' previous medical history or drug treatments, researchers said baricitinib helped their conditions.
"The drug worked well across all patient subgroups, independently of what they'd been taking before or how long they'd had the disease," Dr. Mark Genovese, a professor of immunology and rheumatology at Stanford University, said in a press release.
For the study, published in the New England Journal of Medicine, researchers recruited 527 patients in 24 countries who had rheumatoid arthritis for an average of 14 years, treating them with a 4-milligram dose of baricitinib, 2-milligram dose of baricitinib or placebo.
After 12 weeks of treatment, 55 percent of patients receiving a 4-milligram dose had at least a 20 percent drop in the number of joints affected by the condition, 49 percent of those given the 2-milligram dose saw a reduction, but just 27 percent of placebo patients saw a reduction.
Improvements in the first 12 weeks continued after 24 weeks, the researchers report. Adverse health events were more common 24 weeks into the trial among baracitinib patients, with 77 percent of 4-milligram patients and 71 percent of 2-milligram patients, as compared to 64 percent of those given a placebo.
Results of the phase 3 trial were similar to three previous trials, all of which showed the drug reduced symptoms and prevented structural damage in joints.
"This is the first drug to demonstrate meaningful clinical benefit in patients who've failed virtually every other commercial drug for rheumatoid arthritis," Genovese said.