Etretinate has a much longer elimination half-life compared to that of acitretin. In one study the apparent mean terminal half-life after 6 months of therapy was approximately 120 days (range 84 to 168 days). In another study of 47 patients treated chronically with etretinate, 5 had detectable serum drug levels (in the range of 0.5 to 12 ng/mL) 2.1 to 2.9 years after therapy was discontinued. The long half-life appears to be due to storage of etretinate in adipose tissue.

Progestin-only Contraceptives: It has not been established if there is a pharmacokinetic interaction between acitretin and combined oral contraceptives. However, it has been established that acitretin interferes with the contraceptive effect of microdosed progestin preparations.¹ Microdosed “minipill” progestin preparations are not recommended for use with Soriatane. It is not known whether other progestational contraceptives, such as implants and injectables, are adequate methods of contraception during acitretin therapy.

Clinical Studies

In two double-blind placebo controlled studies, Soriatane was administered once daily to patients with severe psoriasis (ie, covering at least 10% to 20% of the body surface area). At 8 weeks (see Table 1) patients treated in Study A with 50 mg Soriatane per day showed significant improvements (p ≤ 0.05) relative to baseline and to placebo in the physician's global evaluation and in the mean ratings of severity of psoriasis (scaling, thickness, and erythema). In study B, differences from baseline and from placebo were statistically significant (p ≤ 0.05) for all variables at both the 25 mg and 50 mg doses; it should be noted for Study B that no statistical adjustment for multiplicity was carried out.

Table 1. Summary of the Soriatane Efficacy Results of the 8-Week Double-Blind Phase of Studies A and B

Bookmark this page: