INTRODUCTION
In acne vulgaris, the cornerstone of topical treatment is retinoid therapy, including tretinoin (the first topical retinoid used in acne and the gold standard for several years).1 Retinoids, and in particular tretinoin, are well-known to be highly irritating, especially
in the first few weeks of treatment. Therefore, it is necessary to minimize the side effects linked to these treatments, which may also improve patient adherence. Non-compliance in anti-acne therapies is quite frequent, with recent data in both teenagers and adults estimating an adherence rate of only approximately 50%.2-4 Side effects from anti-acne therapies have been reported to impair patient compliance, while clear patient education and a patient's understanding of acne and its treatments may improve adherence.5-6 Patients often seek moisturizers to counteract the drying, irritating effects of retinoids, and the use of such skin care products has been shown to have a positive impact on adherence to anti-acne treatment.3,4
Restoring skin hydration through the use of moisturizers can improve rates of clinical repair in acne and can protect against environmental damage.7 Moisturizers incorporating ceramides have also been found to improve the skin barrier and increase hydration.8-10 Also, protection against the sun is essential, but unfortunately irritation with sunscreens may be a concern to acne patients. Nevertheless, sunscreens are recommended to protect from both acute (sunburn) and chronic (skin cancer, photo-aging) effects of ultraviolet (UV) radiation in all patients,11 Moreover, UV protection is essential in inflammatory diseases of the skin to avoid post-inflammatory hyperpigmentation, in the use of certain drugs (irritating topical retinoids, certain antibiotics,
etc.), or dermatological procedures.
The objective of this study was to assess the benefit of the adjunctive
use of a sun protection factor (SPF) 30 moisturizing lotion containing ceramide precursor in reducing side effects induced by treatment with a topical tretinoin cream.
METHODS
Study Design
This was a randomized, investigator/evaluator-blinded, split-face comparison, single-center study. For 4 weeks, subjects applied a tretinoin cream (Retin A® 0.05% Cream) once daily in the evening (30 minutes after cleansing the face) to the whole face and CDM (Cetaphil® Dermacontrol Oil-Control Facial Moisturizer
SPF 30, Galderma) once daily in the morning to only one side of the face based on the randomization scheme. Study visits were performed at baseline and weeks 1, 2, 3, and 4. This study was conducted in accordance with the ethical principles derived from the Declaration of Helsinki and ICH Good Clinical Practices and in compliance with local regulatory requirements, and was performed with IRB approval. Written informed consent
was obtained from all subjects before entering the study.
Subjects
Subjects were male or female, 18 years of age or older with healthy skin and Fitzpatrick Skin Type I to IV. Exclusion criteria
included skin pigmentation that could have interfered with
