Comparison of Two Different Dosing Regimens with Lymecycline, in Association with Adapalene, in Inflammatory Acne

Combined treatment with oral lymecycline and topical adapalene has been shown to induce greater and faster improvement of acne than monotherapy with lymecycline. We wanted to evaluate the effects of combined therapy with topical adapalene (cream or gel) plus oral lymecycline used at different dosages (group A: 300mg/day for 2 weeks and then 150mg/day for 14 weeks; group B: 300mg/day for 16 weeks) in 242 patients with inflammatory acne. Both dosage regimens were well tolerated in the majority of patients and significantly improved both the acne lesion count and seborrhoea. There was a trend towards a greater reduction of seborrhoea and nodules in patients of group B. After the initial 16-week phase, patients entered an 8-week follow-up phase, consisting of the use of adapalene monotherapy. The results obtained after this phase confirm the therapeutic value and the favourable tolerability of adapalene as maintenance treatment after successful treatment of inflammatory acne. At the same time, a significantly reduced count of comedones was observed in patients of group B as compared with group A, suggesting that prolonged use of high-dose lymecycline may have a more pronounced influence on comedogenesis.

Topical retinoids in acne vulgaris: update on efficacy and safety

Topical retinoids represent a mainstay of acne treatment because they expel mature comedones, reduce microcomedone formation, and exert anti-inflammatory effects. The first-generation retinoid tretinoin (all-trans retinoic acid) and the synthetic third-generation polyaromatics adapalene and tazarotene are approved for acne treatment by the US FDA, whereas topical tretinoin, isotretinoin (13-cis retinoic acid), and adapalene are accredited in Canada and Europe. Topical retinoids have a favorable safety profile distinct from the toxicity of their systemic counterparts. Local adverse effects, including erythema, dryness, itching, and stinging, occur frequently during the early treatment phase. Their impact varies with the vehicle formation, skin type, frequency and mode of application, use of moisturizers, and environmental factors such as sun exposure or temperature. The broad anti-acne activity and safety profile of topical retinoids justifies their use as first-line treatment in most types of non-inflammatory and inflammatory acne. They are also suitable as long-term medications, with no risk of inducing bacterial resistance, for maintenance of remission after cessation of initial combination therapy.

Efficacy of tetracyclines in the treatment of acne vulgaris: a review

BACKGROUND

Oral tetracyclines are routinely used for the management of inflammatory acne. However, there is a lack of evidence-based data on their relative effectiveness and appropriate dosages.

OBJECTIVES

To assess the relative effectiveness and the optimal dosage of tetracyclines for the treatment of inflammatory acne.

METHODS

We designed a systematic review of the clinical trials (1962-2006) investigating oral tetracyclines for the treatment of inflammatory acne. We obtained data from MEDLINE, PubMed, Current Contents, reference lists and specialist textbooks.

RESULTS

There was substantial heterogeneity in the design of the trials. We identified only seven randomized trials which were set up to compare the efficacy of tetracyclines in reducing acne lesion counts. These showed no evidence of superiority of one tetracycline over another. Overall, there was also no significant difference between the available tetracyclines in terms of improvement in inflammatory (32 trials, P=0.898) and noninflammatory (23 trials, P=0.429) lesions. In the range of investigated dosages, the antibiotic dosage had no impact on efficacy in inflammatory (P=0.609) and noninflammatory (P=0.654) lesions. There was no decrease in efficacy during the study period.

CONCLUSIONS

There is insufficient evidence to support one tetracycline rather than another in terms of efficacy. In the range of investigated dosages, the antibiotic dosage seems to have no impact on efficacy. Despite increased resistance to antibiotics, oral tetracycline formulations displayed no change in efficacy during the study period. Further studies are, however, required to determine if the anti-inflammatory properties of tetracyclines are sufficient in managing acne.