Topical imiquimod 5% cream for pediatric plaque morphea: a prospective, multiple-baseline, open-label pilot study.

BACKGROUND/AIMS: Therapeutic options for the treatment of plaque morphea are limited. We explored the efficacy and safety of imiquimod cream in children with plaque morphea.

METHODS: Prospective, open-label, double-baseline study, using imiquimod 5% cream topically for 9 months. The primary outcome measure was improvement in the thickening of morphea plaques using a visual analog scale (VAS) and the DIET score (dyspigmentation/induration/erythema/telangiectasia). Secondary outcome measures were clinicoradiographic correlations and frequency of adverse events.

RESULTS: Nine patients, 89% females, with a mean age of 11.33 years (SD = 3.52) were enrolled. At 36 weeks, the mean VAS had decreased from 48.08 (SD = 18.85) to 22.7 (SD = 12.9) (p < 0.0001), and the mean DIET score from 4.38 (SD = 1.2) to 3.06 (SD = 1.39) (p = 0.23). There was very good interrater reliability between DIET score assessments (intraclass correlation coefficient, ICC = 0.75) and VAS (ICC = 0.59) and moderate agreement between parent and investigator VAS (ICC = 0.5). Ultrasonographically measured dermis thickness changed from 1.05 (SD = 0.34) to 0.95 (SD = 0.19) (p = 0.001). One patient experienced ulceration that required temporary discontinuation of intervention.

CONCLUSIONS: This proof of concept study revealed that imiquimod 5% cream is effective in decreasing the thickening of plaque morphea and safe for pediatric use. Further prospective studies are warranted.