Objective: To determine if minocycline therapy improved skin thickness in early, diffuse systemic sclerosis (SSc) by > or =30%, a level of improvement unlikely to occur in the natural history of the disease as determined by recent controlled trials.
Methods: Subjects with diffuse SSc of < or =5 years' duration were treated with oral minocycline for 1 year. The primary outcome measure was the modified Rodnan skin thickness score (MRSS).
Results: Of 36 subjects initially enrolled, 31 returned for at least 1 followup visit and were included in the analysis (modified intent-to-treat analysis). The group consisted of 23 women and 8 men, with a mean age of 51.7 years (range 26-82 years) and a mean disease duration of 23.5 months (range 6-60 months). The mean MRSS at entry was 22.7 (range 12-43), and at the final visit it was 18.6 (range 2-48). There was no statistically significant difference in the change in skin scores between the minocycline-treated subjects and subjects previously reported in the D-penicillamine (D-Pen) trial. In addition, when adjusted for disease duration, a comparison of MRSS in the minocycline trial subjects (including all subjects active at each time point) and the previously reported D-Pen trial subjects showed no difference and no treatment effect. Fourteen subjects did not complete all 12 months of treatment; 10 of them withdrew due to disease progression. Disease duration was significantly shorter for the noncompleters than for the completers (P < 0.03).
Conclusion: The degree of change in the MRSS was similar to that expected in the natural course of this disease. Based on these data, minocycline is not an effective therapy for SSc.