At least 8 randomized controlled clinical trials have examined the effects of
chloroquine or
hydroxychloroquine on radiographic progression in
rheumatoid arthritis (RA). At least 12 randomized controlled trials have examined the effects of either intramuscular or oral
gold on radiographic progression. A review of these studies shows that
hydroxychloroquine and
chloroquine have minimal, if any, inhibitory effects on radiographically documented progression of bone erosions and joint destruction when used to treat RA. Intramuscular
gold (with most of the data from studies of
sodium aurothiomalate) appears to be better than placebo, about equal to intramuscular
methotrexate (MTX), but probably not as effective as
cyclophosphamide or
azathioprine in its effects on radiographic progression.
Auranofin appears to be better than placebo, comparable to or perhaps moderately less effective than intramuscular
gold, comparable to lower dose oral MTX (7.5 mg/week), and not as effective as higher dose oral MTX (7.5-15 mg/wk) in inhibiting radiographic progression in RA. The inhibitory effects of
gold compounds on proinflammatory
cytokine synthesis (especially
interleukin 1) offer a plausible mechanism for their inhibitory effects on bone erosion and joint destruction in RA.