Clinical safety of tazarotene in the treatment of plaque psoriasis

Prodrugs: design and clinical applications

Prodrugs are bioreversible derivatives of drug molecules that undergo an enzymatic and/or chemical transformation in vivo to release the active parent drug, which can then exert the desired pharmacological effect. In both drug discovery and development, prodrugs have become an established tool for improving physicochemical, biopharmaceutical or pharmacokinetic properties of pharmacologically active agents. About 5-7% of drugs approved worldwide can be classified as prodrugs, and the implementation of a prodrug approach in the early stages of drug discovery is a growing trend. To illustrate the applicability of the prodrug strategy, this article describes the most common functional groups that are amenable to prodrug design, and highlights examples of prodrugs that are either launched or are undergoing human trials.

International Union of Pharmacology. LX. Retinoic acid receptors

Retinoid is a term for compounds that bind to and activate retinoic acid receptors (RARalpha, RARbeta, and RARgamma), members of the nuclear hormone receptor superfamily. The most important endogenous retinoid is all-trans-retinoic acid. Retinoids regulate a wide variety of essential biological processes, such as vertebrate embryonic morphogenesis and organogenesis, cell growth arrest, differentiation and apoptosis, and homeostasis, as well as their disorders. This review summarizes the considerable amount of knowledge generated on these receptors.

Oral lichen planus: a preliminary clinical study on treatment with tazarotene

OBJECTIVE

The rationale for using tazarotene in oral lichen planus (OLP) is its regulatory action on the growth and differentiation of keratinocytes and on inflammation. This randomized, placebo-controlled study addresses evaluation of the effects of topic tazarotene in the treatment of OLP.

DESIGN

The degree of lesions before and after treatment scored by a 6-score scale in six cases treated with tazarotene was statistically compared with those of six controls treated with placebo.

SUBJECTS

Twelve patients with hyperkeratosic OLP were randomly allocated to treatment with tazarotene gel 0.1% b.i.d. or with placebo for eight consecutive weeks.

METHODS

The statistical comparison was executed by means of Wilcoxon analysis for paired data.

RESULTS

Patients treated with tazarotene presented a significant reduction of their lesions as compared with the control group. Among transitory side-effects, burning sensation and taste abnormalities were observed.

CONCLUSION

Topical tazarotene may be a valuable therapeutic tool in the treatment of hyperkeratotic OLP.

Psoriasis: current perspectives with an emphasis on treatment

An individualized treatment regimen is necessary for each patient with psoriasis because of the diverse nature of the disease. The manifestation of psoriasis, the severity and extent of the lesions, and the medical history and lifestyle of the patient are important factors that determine the selection of treatment, but in general therapies with the fewest side effects are preferred. First-line topical treatments are corticosteroids, calcipotriene, and tazarotene. If topical treatments are unsuccessful, phototherapy with ultraviolet B or photochemotherapy with psoralens plus ultraviolet A (PUVA) are the next choices. If psoriasis fails to respond to an adequate trial of topical therapy or phototherapy, systemic therapies including methotrexate, acitretin, or cyclosporin should be initiated. Because the regimens involved in systemic and phototherapy are complex and require frequent dose adjustments and specialized equipment, the patient should be referred to a dermatologist when topical therapy is not effective.

Effect of topical tazarotene in the treatment of congenital ichthyoses

The clinical efficacy and tolerability of the topical receptor-selective retinoid tazarotene in the treatment of congenital ichthyoses was investigated. Twelve consecutive patients with different forms of congenital ichthyosis were enrolled in an open, non-randomized, intraindividually controlled, half-side pilot study. Diagnoses were X-linked recessive ichthyosis, non-erythrodermic autosomal recessive lamellar ichthyosis, autosomal dominant ichthyosis vulgaris and ichthyosis bullosa of Siemens (IBS). Tazarotene 0.05% gel was applied unilaterally daily on a defined body area measuring 10% of the body surface area. The contralateral side was treated with an ointment containing 10% urea. After 14 days, application frequency was reduced to three times a week, and stopped after another 2 weeks. The follow-up period was 3 months. Reduction in scaling and roughness was used to assess the clinical response in the tazarotene-treated area compared with the control area. Clinical and laboratory assessments were performed every 14 days during the trial. Unilateral improvement in favour of the tazarotene-treated side was observed in nine of 12 patients (75%). Four patients (33%) achieved an excellent response and four (33%) achieved a good response. No therapeutic effect was seen in patients with IBS. The remission persisted during the reduction phase and after discontinuation for up to 2 months. Local irritation in three patients was the only side-effect detectable. Short-term topical application of tazarotene 0.05% gel is a very effective and well-tolerated treatment modality in different forms of congenital ichthyoses and may be an alternative to systemic retinoid therapy.