N-[4-hydroxyphenyl] retinamide in rheumatoid arthritis: a pilot study

Abstract

Objective: To evaluate the efficacy and tolerability of N-[4 hydroxyphenyl] retinamide (4-HPR), a synthetic retinoid, in the treatment of rheumatoid arthritis (RA).

Methods: An uncontrolled, open clinical trial with synovial biopsy pre- and postmedication to evaluate the clinical effects of 4-HPR as well as its effects on metalloproteinase gene expression.

Results: Twelve patients with severe, longstanding RA were enrolled in this study. Six patients withdrew before study completion, 2 because of drug toxicity, 2 because of a flare of RA, and 2 because of intercurrent medical problems. No patient met predetermined Paulus criteria treatment response, and there was no improvement in the laboratory parameters, except for a modest decrease in C-reactive protein. No decrease in messenger RNA for the metalloproteinases collagenase and stromelysin was seen in the 2 patients in whom paired synovial biopsies were obtained.

Conclusion: No beneficial clinical effect was observed with the retinoid 4-HPR in the treatment of severe, longstanding RA at the 300 mg/day dosage studied. The use of higher dosages is precluded by the observed toxicities. The effect of this drug in patients with early or mild disease was not studied. Although this particular retinoid was not effective in this pilot study, the use of other retinoids in RA should still be considered.