Hormonal modulation in systemic lupus erythematosus. Preliminary clinical and hormonal results with cyproterone acetate.

We prospectively studied the effects of hormonal modulation using the antigonadotropic drug, cyproterone acetate (CA), in 7 female patients who had moderately active systemic lupus erythematosus. CA was taken orally at a mean daily dose of 50 mg for 21-33 months by 6 patients (9 months by the seventh patient) without any side effects. The number of clinical lupus exacerbations during CA treatment was lower than that during the corresponding pretreatment period (15 of 170 patient-months versus 27 of 156 patient-months; P less than 0.05), despite a reduction in the daily maintenance dose of corticosteroids or antimalarial drugs. Mean plasma testosterone levels were low initially and remained unchanged (0.66 +/- 0.31 to 0.59 +/- 0.23 nmoles/liter), whereas plasma estradiol decreased markedly (from 0.6 +/- 0 38 to 0.11 +/- 0.03 nmoles/liter), resulting in a significant reduction in the estradiol:testosterone ratio (from 1.19 +/- 0.68 to 0.23 +/- 0.12) and in the plasma concentration of the sex hormone-binding protein. Thus, cyproterone acetate induced improvement in clinical lupus activity in parallel with the expected lower estradiol:testosterone balance.