[Effect of 13-cis-retinoic acid (Ro 4-3780) in the therapy of severe cystic acne].

Five subjects with serious cystic acne, two of which were also affected by hydrosadenitis, were examined during a treatment with 13-cis-retinoic acid. The drug was given at decreasing doses: 0.9 mg/kg body weight for a period of six weeks, followed by a second six weeks period at 0.6 mg/kg and lastly by another 9 months period at 0.3 mg/kg. The patients had a good response to the treatment with a rapid reduction of the number and of the severity of the acneic lesions, with the only exception of one subject who had a relapse at the 18th week. This study, limited to a small number of patients, suggest that 13-cis-retinoic acid may be used in severe cystic acne with a higher dosage in the presence of complicating hydrosadenitis.