TNF inhibitor failed to improve severe hand osteoarthritis

WASHINGTON, DC - Adalimumab, a tumor necrosis factor (TNF) inhibitor commonly used to treat rheumatoid arthritis (RA), failed to improve severe hand osteoarthritis (OA) in a randomized, double-blind, placebo-controlled trial, researchers reported at here ACR.

"New drugs are sorely needed to treat hand osteoarthritis, a painful condition that doesnt respond to analgesics or NSAIDs [nonsteroidal antiinflammatory drugs," said lead author Xavier Chevalier, MD, from Hopital Henri Mondor in Paris.

The mechanism of cartilage degradation and pain transmission in OA are similar to those of RA, so it was logical to study a TNF inhibitor in this setting, Dr. Chevalier explained.

The Digital Arthritis in Refractory Hand OA (DORA) trial enrolled patients with painful hand OA that did not respond to other medications, including NSAIDs. Patients were enrolled from 16 different sites in France. All patients fulfilled ACR criteria for hand OA, with significant pain, at least 3 painful interphalangeal hand joints, and a minimum of 3 involved joints on radiography.

Researchers randomly assigned patients (n = 85) to receive adalimumab (subcutaneous injection at the start of the trial and again 2 weeks later) or matching placebo. The primary endpoint was the difference between the groups in mean change from baseline to 6 weeks.

At baseline, all patients had pain scores greater than 40 mm on a 100-mm visual analogue pain scale, with a mean pain score of 65.4 mm. At 6 weeks, the mean difference in the change from baseline between the 2 groups was just –2.5 in favor of the adalimumab group, which was not a statistically significant difference.

"The study was negative for the main outcome and all secondary outcomes, including number of swollen and painful joints. There was no effect on biomarkers of cartilage turnover as well," Dr. Chevalier said.

"Two injections of anti-TNF do not alleviate pain, but we need something new in OA," he continued.

He said that it was possible that the negative findings in the trial were due to the limited number of TNF injections. TNF may not be a good target, he said, but would require more treatment. Also, it is possible that patients with an inflammatory component would respond.

"Although we studied pain, the important goal is to slow down disease progression," he said.

Kathryn Dao, MD, associate director of clinical rheumatology at Baylor Research Institute in Dallas, Texas, and moderator of the press conference in which these findings were discussed, noted that tanezumab, a drug targeted to nerve growth factor, showed positive results in alleviating pain of hip and knee OA in previous studies and may have an eventual role in treating hand OA.

"That is an interesting drug. It may have applications in hand OA. We will need to balance the risk versus benefit of this drug and use it in the right patient population, that is patients with no other alternatives in severe pain with poor quality of life," she said.

 

Cindy