By Pat Anson, Editor

Hydroxychloroquine (Plaquenil) is a medication commonly used to treat rheumatoid arthritis, lupus and other autoimmune diseases. It’s also being prescribed off-label to treat inflammation and pain caused by hand osteoarthritis, a joint condition that affects nearly a third of patients over the age of 70.

But in a new study published in the Annals of Internal Medicine, British researchers reported that hydroxychloroquine is no more effective than a placebo in relieving moderate to severe pain caused by hand osteoarthritis.

Researchers at the Leeds Institute of Rheumatic and Musculoskeletal Medicine and the Leeds Biomedical Research Centre randomly assigned 248 patients with radiographic hand osteoarthritis to either hydroxychloroquine (200 to 400 mg) or placebo for a year.

Most of the patients had symptoms of hand osteoarthritis for about 5 years, and their average pain level was 7 out of 10.

After 3, 6 and 12 months, there were no significant differences in treatment outcomes between the hydroxychloroquine and placebo groups.

“We found that HCQ (hydroxychloroquine) was not a more effective analgesic than placebo when added to usual care in persons with moderate to severe hand osteoarthritis,” researchers reported. “Background analgesic use did not differ between groups, and baseline inflammation and structural damage did not affect response to HCQ. The study therefore presents no evidence that HCQ should be considered within the management plan of patients with hand osteoarthritis.”

Two doctors who reviewed the study say more research is needed to find drugs that can treat the inflammation caused by hand osteoarthritis, a condition for which there are no effective therapies.

“The negative findings in this carefully done trial beg the question of what went awry. Did HCQ fail to reduce inflammation, or did reduced inflammation not translate to pain relief?” wrote Elena Losina, PhD, and Jefferey Katz, MD in an editorial.

“Although HCQ is safe, it is also a weak anti-inflammatory agent seldom used in contemporary practice as a solo disease-modifying therapy for rheumatoid arthritis and other inflammatory conditions. Further therapeutic studies of the effects of anti-inflammatory therapy on nodal hand osteoarthritis will need to use more potent agents or compounds developed to more specifically target the inflammatory pathways documented in this condition.”