Nineteen RCTs were included in the review (n=7,378): 10 of pimecrolimus (n=2,959) and nine of tacrolimus (n=4,419). Seven studies were rated as highly generalisable and five were noted to have high internal validity. [A: Eleven RCTs reported adequate methods of randomisation, three reported adequate allocation concealment, all used adequate or double blinding, 16 used intention-to-treat analysis and 10 reported power calculations.]
Pimecrolimus 1% was significantly more effective than placebo at three weeks (RR 2.41, 95% CI 1.31 to 4.43; four RCTs) and six weeks (RR 2.05, 95% CI 1.52 to 2.76; two RCTs). There was significant statistical heterogeneity (p=0.02) for the three-week outcome. No statistically significant difference between the groups in effectiveness was found at six or 12 months (one RCT). Findings for secondary outcomes were also significantly superior in the pimecrolimus group.
One RCT found that for moderate to severe atopic dermatitis, pimecrolimus was significantly less effective than a potent topical corticosteroid at three weeks (RR 0.22, 95% CI: 0.09 to 0.54). A second RCT reported that combined potent/mild topical corticosteroid was significantly more effective than pimecrolimus for up to six months (RR 0.89, 95% CI 0.83 to 0.9).
One of three relevant studies reported that in children tacrolimus 0.03% was significantly more effective than placebo at three weeks (RR 2.13, 95% CI: 1.24 to 3.68; one RCT), but tacrolimus 0.1% was not (one RCT). The remaining two RCTs (one in children and one in adults) reported that both 0.03% and 0.1% tacrolimus were significantly more effective than placebo at 12 weeks (RR 4.53, 95% CI 2.93 to 7.00 for 0.03% tacrolimus; RR 5.69, 95% CI 3.72 to 8.72 for 0.1% tacrolimus).
Tacrolimus 0.03% (RR 2.56, 95% CI 1.95 to 3.36; two RCTs) and 0.1% (RR 3.09, 95% CI 2.14 to 4.45; one RCT) were both significantly more effective than a mild topical corticosteroid at three weeks. Single RCTs conducted among adults with moderate to severe atopic dermatitis found that at three weeks tacrolimus 0.03% was significantly less effective than a moderate topical corticosteroid (RR 0.74, 95% CI 0.59 to 0.93), but tacrolimus 0.1% was not significantly different from the moderate topical corticosteroid. At six months tacrolimus 0.1% was significantly more effective than a combined potent/mild topical corticosteroid (p=0.00001).