The safety and efficacy of pimecrolimus, 1%, cream for the treatment of Netherton syndrome: results from an exploratory study.

BACKGROUND Impaired skin integrity in patients with Netherton syndrome (NS) results in significant systemic absorption of topically applied medications. Some have advocated the administration of pimecrolimus, 1%, topical cream for the treatment of patients with NS. Insufficient data exist with regard to its safety, systemic absorption, and efficacy. OBSERVATIONS An exploratory study was conducted involving 3 children with NS who received twice-daily application of pimecrolimus, 1%, cream over 18 months. There were no notable abnormalities in hematologic or chemistry profiles. Blood levels of pimecrolimus ranged from 0.625 to 7.08 ng/mL, with peak levels reached during the first month in all 3 patients. Dramatic reductions were observed in the Netherton Area and Severity Assessment, Eczema Area and Severity Index, Investigator Global Evaluation of Disease, and pruritus scores compared with baseline levels. CONCLUSIONS Use of pimecrolimus, 1%, cream was well tolerated and demonstrated marked improvements in nearly all of the parameters evaluated. Patients treated with pimecrolimus responded rapidly, within the first month of treatment, and improvement persisted throughout the study period. In adult patients receiving oral pimecrolimus, blood levels as high as 54 ng/mL for 3 months have not shown clinically significant immunosuppression. Absorption of pimecrolimus, 1%, cream was detectable, but levels were much lower than expected even when applied to 50% of total body surface area. Larger studies are warranted to determine the safety and efficacy of pimecrolimus, 1%, cream in the treatment of NS. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00208026.