Adapalene gel, 0.1%, as maintenance therapy for acne vulgaris: a randomized, controlled, investigator-blind follow-up of a recent combination study

OBJECTIVE: To assess the maintenance effect of adapalene gel, 0.1%, relative to gel vehicle in subjects successfully treated in a previous 12-week study of adapalene-doxycycline, 100 mg, combination therapy. DESIGN: Multicenter, investigator-blind, randomized, controlled study. SETTING: Thirty-four US centers. SUBJECTS: A total of 253 subjects with severe acne vulgaris who showed at least moderate improvement from baseline (50% improvement from baseline) when treated with either adapalene plus doxycycline or doxycycline plus gel vehicle in a previous 12-week study. INTERVENTIONS: Subjects were randomized to receive adapalene gel, 0.1%, or gel vehicle once daily for 16 weeks. MAIN OUTCOME MEASURES: Efficacy and safety criteria included maintenance rate (subjects maintaining at least 50% improvement in lesion counts from previous therapy), lesion counts (total, inflammatory, and noninflammatory), global severity assessment, cutaneous tolerability, and adverse events. RESULTS: Adapalene maintenance therapy resulted in significantly larger maintenance rates (75% vs 54%; P<.001) and significantly lower lesion counts (total [P = .005], inflammatory [P = .01], and noninflammatory [P = .02]) compared with gel vehicle. Adapalene was safe and well tolerated in this study.Conclusion This study demonstrates a clinical benefit of continued treatment with adapalene gel, 0.1%, as a maintenance therapy for acne.     

Adapalene 0.1%/Benzoyl Peroxide 2.5% Gel

Adapalene 0.1%/benzoyl peroxide 2.5% gel (Epiduo?, Tactuo?) is the only fixed-dose combination product available that combines a topical retinoid with benzoyl peroxide; it targets three of the four main pathophysiologic factors in acne. This article reviews the therapeutic efficacy and tolerability of topical adapalene 0.1%/benzoyl peroxide 2.5% gel in the treatment of patients aged ≥ 12 years with acne vulgaris, as well as summarizing its pharmacologic properties. In three 12-week trials in patients aged ≥12 years with moderate acne, success rates were significantly higher with adapalene 0.1%/benzoyl peroxide 2.5% gel than with adapalene 0.1% gel or benzoyl peroxide 2.5% gel alone, and combination therapy had an earlier onset of action. In addition, significantly greater reductions in total, inflammatory, and noninflammatory lesion counts were seen in patients receiving adapalene 0.1%/benzoyl peroxide 2.5% gel than in those receiving adapalene 0.1% gel or benzoyl peroxide 2.5% gel alone. Adapalene 0.1%/benzoyl peroxide 2.5% gel did not significantly differ from clindamycin 1%/benzoyl peroxide 5% gel in terms of the reduction in the inflammatory, noninflammatory, or total lesion counts in patients with mild to moderate acne, according to the results of a 12-week trial. Twelve-week studies showed that topical adapalene 0.1%/benzoyl peroxide 2.5% gel in combination with oral lymecycline was more effective than oral lymecycline alone in patients with moderate to severe acne, and topical adapalene 0.1%/benzoyl peroxide 2.5% gel in combination with oral doxycycline hyclate was more effective than oral doxycycline hyclate alone in patients with severe acne. In patients with severe acne who responded to 12 weeks’ therapy with topical adapalene 0.1%/benzoyl peroxide 2.5% gel plus oral doxycycline hyclate or oral doxycycline hyclate alone, an additional 6 months’ therapy with adapalene 0.1%/benzoyl peroxide 2.5% gel was more effective than vehicle gel at maintaining response, with further improvement seen in adapalene 0.1%/benzoyl peroxide 2.5% gel recipients. A noncomparative study also demonstrated the efficacy of 12 months’ therapy with adapalene 0.1%/benzoyl peroxide 2.5% gel in patients with acne vulgaris. Topical adapalene 0.1%/benzoyl peroxide 2.5% gel was generally well tolerated in patients with acne. In 12-week trials, the most commonly occurring treatment-related adverse events included erythema, scaling, dryness, and stinging/burning; these dermatologic treatment-related adverse events were usually of mild to moderate severity, occurred early in the course of treatment, and resolved without residual effects. Topical adapalene 0.1%/benzoyl peroxide 2.5% gel was generally well tolerated in the longer term, with dry skin being the most commonly occurring treatment-related adverse event over 12 months of treatment. In conclusion, adapalene 0.1%/benzoyl peroxide 2.5% gel is a valuable agent for the first-line treatment of acne vulgaris.     

The efficacy and safety of adapalene gel 0.3% in the treatment of acne vulgaris: A randomized, multicenter, investigator-blinded, controlled comparison study versus adapalene gel 0.1% and vehicle

A randomized, multicenter, investigator-blinded, active- and vehicle-controlled study was conducted to evaluate the efficacy and safety of adapalene gel 0.3% versus adapalene gel 0.1% and the corresponding gel vehicle. Subjects were assigned randomly to receive either adapalene gel 0.3%, adapalene gel 0.1%, or vehicle once daily for 12 weeks. A total of 214 subjects with moderate to moderately severe acne vulgaris were enrolled, and 85% of subjects completed the study. Adapalene gel 0.3% was significantly superior to adapalene gel 0.1% in total and noninflammatory lesion counts and in global severity score (P < .05 for all). A concentration-dependent increase in clinical benefit for all efficacy assessments was observed. As expected, there were also statistically significant differences in all efficacy parameters in the adapalene gel 0.3% group relative to the vehicle group (P < .001 for all). Treatment-related adverse events were mostly mild-to-moderate and similar between active groups. The results of this study show that adapalene gel 0.3% was superior to adapalene gel 0.1% and vehicle in the treatment of moderate to moderately severe acne while retaining a similar safety and tolerability profile to adapalene 0.1% gel.     

Adapalene gel 0.1% is effective and safe for Japanese patients with acne vulgaris: a randomized, multicenter, investigator-blinded, controlled study

BACKGROUND: Topical retinoids, such as adapalene, are an integral part of acne therapy in most regions and are considered appropriate first-line therapy by international guidelines for all cases of acne with the exception of the most severe. However, there are currently no topical retinoids available for the treatment of acne vulgaris in Japan. OBJECTIVE: To confirm efficacy and safety of adapalene gel 0.1% versus the corresponding gel vehicle in the treatment of Japanese patients with acne vulgaris for up to 12 weeks. METHODS: A total of 200 patients were randomized to receive adapalene gel 0.1%, or vehicle once-daily for 12 weeks. Percent reduction in lesion counts (total, inflammatory, and non-inflammatory) and subject satisfaction were evaluated. Safety was monitored through adverse events and laboratory tests. RESULTS: Adapalene gel 0.1% produced significantly better reductions in total (P<0.0001), inflammatory (P=0.0010), and non-inflammatory lesions (P<0.0001) at endpoint (week 12, last observation carried forward) than gel vehicle, with a higher overall subject satisfaction. The primary efficacy variable, the median percent reduction of total lesion counts at endpoint, was significantly greater with adapalene gel 0.1% (63.2%) compared to that with the vehicle (36.9%) in the ITT population (P<0.0001). Significantly greater results were observed as early as week 1. Adapalene was well tolerated, with adverse events that were mostly mild-to-moderate and transient in nature. CONCLUSIONS: Adapalene gel 0.1% was effective in the treatment of acne vulgaris in Japanese patients. Adapalene was safe and well tolerated, consistent with the good tolerability profile demonstrated in other patient populations.     

0.1%阿达帕林凝胶预防和减轻寻常痤疮复发的多中心随机对照临床试验

目的评价0.1%阿达帕林凝胶维持治疗对于预防和减轻寻常痤疮复发的作用.方法采用多中心、区组随机、开放、对照的方法,共入选患者246例,均为经过阿达帕林和克林霉素(特丽仙)联合治疗或特丽仙单独治疗获得有效(改善≥25%)的寻常痤疮患者,随机分为两组,一组外用0.1%阿达帕林凝胶,另一组不用药,均观察12周.结果239例患者完成治疗和观察,阿达帕林组121例,对照组118例.治疗4周后阿达帕林组炎性皮损数的减少显著优于对照组(P＜0.05),并维持至12周;治疗8周后阿达帕林组皮损总数和非炎性皮损数的减少也显著优于对照组(P＜0.01),并维持至12周.治疗结束后,阿达帕林组总体改善率为66.9%,对照组为4.2%(P＜0.01);阿达帕林组总复发率为4.1%,对照组为83.9%;两组间差异有显著性(P＜0.01).阿达帕林组有个别病例有轻度局部刺激反应,两组间不良反应差异无显著性(P＜0.05).结论阿达帕林凝胶可有效地治疗寻常痤疮,并维持治疗效果,且不增加局部刺激反应,对于减少病情复发具有显著效果.     

Control of microcomedone formation throughout a maintenance treatment with adapalene gel, 0.1%

BACKGROUND: Microcomedones representing the clinically non-visible central precursor lesions of acne are induced by sebaceous hyperplasia as well as altered follicular growth and differentiation, and evolve into both comedones and inflammatory lesions. Thus, targeting microcomedone formation is essential in the prevention and therapeutic control of acne. OBJECTIVE: The aim of this study was to assess the capacity of adapalene gel, 0.1%, to control the number of microcomedones after a combination treatment followed by a maintenance treatment. METHODS: This was a single-site exploratory study in subjects with a diagnosis of mild to moderate acne vulgaris and the presence of at least 250 microcomedones per cm(2) at screening visit, counted via cyanoacrylate strips (CyASt). During the first 8 weeks, a combination of adapalene gel (0.1%) and benzoyl peroxide gel (2.5%) was applied. During the randomized, investigator-blinded, and vehicle-controlled 12-week maintenance phase, adapalene once daily (QD), or adapalene alternately with its vehicle once daily every other day (QoD), or vehicle QD were applied to the face. CyASt sampling on the forehead was done at baseline, week 8, and week 20. Lesion counting allowing calculating a defined success rate was done at all visits. RESULTS: A total of 54 subjects entered the combination phase, and 49 subjects were randomized into the maintenance phase: 16 in both the adapalene QD and the QoD group and 17 subjects receiving the vehicle. The microcomedone median count decreased for all groups until week 8 (end of combination phase) from 319 to 157. Microcomedone counts at the end of the maintenance phase (week 20) showed a significant percent difference (P = 0.04) between adapalene QoD (-53.5) and the vehicle (-42.1) and between adapalene QD (-50.6) and the vehicle (P = 0.037) compared with baseline. CONCLUSION: The application of adapalene gel, 0.1% monotherapy daily, or alternately every other day, significantly helps to control the microcomedone count during a 12-week maintenance treatment after a previous combination therapy with benzoyl peroxide in patients with mild to moderate acne.     

A 6-month maintenance therapy with adapalene-benzoyl peroxide gel prevents relapse and continuously improves efficacy among patients with severe acne vulgaris: results of a randomized controlled trial

Background Acne vulgaris is a chronic and frequently recurring disease. A fixed‐dose adapalene‐benzoyl peroxide (adapalene‐BPO) gel is an efficacious and safe acne treatment. Objectives To assess the long‐term effect of adapalene‐BPO on relapse prevention among patients with severe acne after successful initial treatments. Methods This is a multicentre, double‐blind, randomized and controlled study. In total, 243 subjects who had severe acne vulgaris and at least 50% global improvement after a previous 12‐week treatment were randomized into the present study to receive adapalene‐BPO gel or its vehicle once daily for 24 weeks. Results At week 24, compared with vehicle, adapalene‐BPO resulted in significantly higher lesion maintenance success rate (defined as having at least 50% improvement in lesion counts achieved in initial treatment) for all types of lesions (total lesions: 78·9% vs. 45·8%; inflammatory lesions: 78·0% vs. 48·3%; noninflammatory lesions: 78·0% vs. 43·3%; all P < 0·001). Significantly more subjects with adapalene‐BPO than with vehicle had the same or better Investigator’s Global Assessment score at week 24 than at baseline (70·7% vs. 34·2%; P < 0·001). The time when 25% of subjects relapsed was 175 days with adapalene‐BPO and 56 days with vehicle (17 weeks earlier; P < 0·0001). Adapalene‐BPO led to further decrease of lesion counts during the study and 45·7% of subjects were ‘clear’ or ‘almost clear’ at week 24. It was also safe and well tolerated in the study. Conclusions Adapalene‐BPO not only prevents the occurrence of relapse among patients with severe acne, but also continues to reduce disease symptoms during 6 months.     

Randomised,controlled trial of the efficacy and safety of adapalene gel 0.1% and tretinoin cream 0.05% in patients with acne vulgaris

BACKGROUND: Previous clinical trials have shown that adapalene gel produces less irritation than tretinoin gels and tretinoin 0.025% cream. Short term results have shown that adapalene is less irritating than tretinoin gels and creams. This study is the first to compare the 0.1% formulation of adapalene gel with the 0.05% strength of tretinoin cream in a formal clinical trial. OBJECTIVE: To investigate the efficacy and tolerability of adapalene gel 0.1% compared with tretinoin cream 0.05% in patients with mild-to-moderate acne vulgaris. METHODS: Ten-week, multicentre, randomised, investigator-masked, active-controlled, parallel group study in 409 patients with acne vulgaris. RESULTS: Adapalene gel 0.1% demonstrated equivalent efficacy in reduction of acne lesion counts and global improvement of acne severity over 10 weeks' treatment and was significantly better tolerated than tretinoin cream 0.05% in terms of erythema, dryness, desquamation and stinging/burning. CONCLUSION: Adapalene gel 0.1% showed equivalent efficacy and was significantly better tolerated than tretinoin cream 0.05% in patients with mild-to-moderate acne vulgaris.     

阿达帕林凝胶治疗寻常痤疮10年回顾

目的 总结阿达帕林凝胶治疗寻常痤疮的临床文献,为临床合理用药提供参考。方法 对阿达帕林凝胶上市10年来国内有关治疗寻常痤疮的疗效及安全性观察的中文文献进行整理和分析。结果 联合用药组疗效高于单用药物组,阿达帕林凝胶组疗效与其他维A酸类药物疗效相当,但高于其他痤疮药物组,不良反应低于其他药物。结论 阿达帕林凝胶治疗轻中度痤疮安全、有效,可单独或联合用药,还可作为维持治疗。     

Combination therapy with adapalene-benzoyl peroxide and oral lymecycline in the treatment of moderate to severe acne vulgaris: a multicentre, randomized, double-blind controlled study

Background Oral antibiotics in association with a topical retinoid with or without benzoyl peroxide (BPO) are the recommended first‐line option in the treatment of moderate to severe acne vulgaris. Objectives To evaluate the efficacy and safety of oral lymecycline 300 mg with adapalene 0·1%–BPO 2·5% (A/BPO) fixed‐dose gel in comparison with oral lymecycline 300 mg with a vehicle gel in subjects with moderate to severe acne vulgaris. Methods A total of 378 subjects were randomized in a double‐blind, controlled trial to receive once‐daily lymecycline with either A/BPO or vehicle for 12 weeks. Evaluations included percentage changes from baseline in lesion counts, success rate (subjects ‘clear’ or ‘almost clear’), skin tolerability, adverse events and patients’ satisfaction. Results The median percentage reduction from baseline in total lesion counts at week 12 was significantly higher (P < 0·001) in the lymecycline with A/BPO group (?74·1%) than in the lymecycline with vehicle group (?56·8%). The success rate was significantly higher (47·6% vs. 33·7%, P = 0·002) in subjects treated with lymecycline and A/BPO. Both inflammatory and noninflammatory lesions were significantly reduced at week 12 (both P < 0·001) with a rapid onset of action from week 2 for noninflammatory lesions (P < 0·001) and week 4 for inflammatory lesions (P = 0·005). The A/BPO and lymecycline combination was well tolerated. The proportion of satisfied and very satisfied subjects was similar in both groups, but the number in the A/BPO group who were ‘very satisfied’ was significantly greater (P = 0·031). Conclusion These results demonstrate the clinical benefit of combining A/BPO with lymecycline in the treatment of moderate to severe acne vulgaris.     

Topical adapalene gel 0.1% vs. isotretinoin gel 0.05% in the treatment of acne vulgaris: a randomized open-label clinical trial

BACKGROUND: Topical application of isotretinoin and adapalene has proved effective in treating acne vulgaris. Both drugs demonstrate therapeutic advantages and less irritancy over tretinoin, the most widely used treatment for acne. They both act as retinoid agonists, but differ in their affinity profile for nuclear and cytosolic retinoic acid receptors. OBJECTIVE: To compare the efficacy and tolerability of adapalene gel 0.1% and isotretinoin gel 0.05% in the treatment of acne vulgaris of the face, in a randomized open-label clinical trial. METHODS: Eighty patients were enrolled and were instructed to apply adapalene gel 0.1% or isotretinoin gel 0.05% once daily over a 12-week treatment period. Efficacy determination included noninflammatory and inflammatory lesion counts by the investigator and global evaluation of improvement. Cutaneous tolerance was assessed by determining erythema, scaling and burning with pruritus. RESULTS: Adapalene and isotretinoin gels were highly effective in treating facial acne. Adapalene gel produced greater reductions in noninflammatory and inflammatory lesion counts than did isotretinoin gel, but differences between treatments were not statistically significant. Adapalene gel was significantly better tolerated than isotretinoin gel during the whole treatment period. CONCLUSIONS: The two gels studied demonstrated comparable efficacy. When adapalene and isotretinoin were compared, significantly lower skin irritation was noted with adapalene, indicating that adapalene may begin a new era of treatment with low-irritant retinoids.     

Spotlight on Adapalene in Acne Vulgaris

Adapalene (Differin) is a retinoid agent indicated for the topical treatment of acne vulgaris. In clinical trials, 0.1% adapalene gel has proved to be effective in this indication and was as effective as 0.025% tretinoin gel, 0.1% tretinoin microsphere gel, 0.05% tretinoin cream and 0.1% tazarotene gel once every two days; however, the drug was less effective than once-daily 0.1% tazarotene gel. It can be used alone in mild acne or in combination with antimicrobials in inflammatory acne and has proved efficacious as maintenance treatment. Adapalene has a rapid onset of action and a particularly favorable tolerability profile compared with other retinoids. These attributes can potentially promote patient compliance, an important factor in treatment success. Adapalene is, therefore, assured of a role in the first-line treatment of acne vulgaris.     

Topical retinoids in acne – an evidence‐based overview

Topical retinoids are important tools in the management of acne because they act against comedones and microcomedones and have direct anti‐inflammatory effects. The substances approved for acne treatment comprise tretinoin (all‐trans‐retinoic acid),isotretinoin (13‐cis retinoic acid) as well as the synthetic third‐generation polyaromatic retinoids adapalene and tazarotene,the latter being approved for acne treatment in the US only.Retinaldehyde is used in cosmetic preparations against acne. All topical retinoids are effective as single agents in mild to moderate acne but differ in efficacy and tolerability. Tazarotene 0.1% is more effective than tretinoin 0.025% or 0.1% microsphere gel or adapalene 0.1% gel or cream (EBM‐level 2c). Adapalene 0.1% is equally effective to tretinoin 0.025% or tretinoin microsphere 0.1% gel or tretinoin 0.05% cream or isotretinoin 0.05% gel (EBM‐level 2c). Adapalene 0.1% gel is significantly better tolerated than tazarotene 0.1% gel, tretinoin 0.025% and tretinoin 0.05% gel, tretinoin 0.05% cream,tretinoin microsphere 0.1% gel or isotretinoin 0.05% gel (EBM‐level 2c).The safety profile of topical retinoids differs from their systemic counterparts and is related mainly to local adverse effects, such as erythema, dry‐ness,itching and stinging.The currently available evidence justifies the use of topical retinoids in most types of acne and during maintenance treatment.     

Adapalene gel 0.1% in the treatment of infantile acne: an open clinical study

Abstract:  Infantile acne is an uncommon condition in pediatric age. We determined the efficacy and safety of adapalene gel 0.1% in the treatment of infantile acne. Twelve patients were enrolled for adapalene gel 0.1% application once daily over a 16-week treatment period. Efficacy evaluation included counting the inflammatory and noninflammatory lesions by the physician and global evaluation of the improvement. After 16 weeks all patients were followed up for a 1-year period. The time of clearance of the infantile acne lesions was 3 months in four (33%) patients and 4 months in eight (67%) patients (median 3.4 months). Adapalene gel produced reductions in noninflammatory and inflammatory lesions counts. Limited side effects were observed and none of them required stopping the therapy. No patient was left with scarring. Three patients were showed mild lesions in the 1-year follow-up period. Adapalene gel 0.1% was found to be a highly effective and safe drug in the treatment of mild-to-moderate infantile acne.     

Clinical and bacteriological evaluation of adapalene 0.1% gel plus nadifloxacin 1% cream versus adapalene 0.1% gel in patients with acne vulgaris

This multicenter, randomized parallel group study investigated the efficacy and tolerability of adapalene 0.1% gel plus nadifloxacin 1% cream (combination therapy) compared with adapalene gel (monotherapy) during 12‐week treatment of acne vulgaris. A total of 184 Japanese patients aged above 12 years with moderate to severe acne as indicated by the Japanese severity grading criteria were randomized to combination therapy (n = 84) and monotherapy (n = 100) groups, both having comparable demographic and baseline characteristics. Adapalene was applied only to inflammatory acne lesions in order to minimize skin irritation and ensure the treatment results. Efficacy and safety evaluations, treatment compliance and satisfaction with drug application were periodically monitored. The combination therapy provided a significantly greater efficacy than adapalene in decrement of inflammatory papulopustular lesions at 4 weeks and thereafter (P = 0.0056). The overall judgment of the therapeutic efficacy by the physician at the end of study revealed a significant difference (P = 0.02496) between the groups in favor of combination therapy. Dryness was reported in a greater proportion of patients undergoing monotherapy than combination therapy at weeks 2 and 4 (P = 0.04652). The patient self‐assessment in satisfaction with the drug application at the end of study revealed a significant difference (P = 0.00268) between the groups in favor of combination therapy. Among 76 strains of Propionibacterium acnes isolated from 87 patients, no strain was resistant to nadifloxacin. Thus, the simultaneous use of adapalene and nadifloxacin may provide an additive and complementary effect, resulting in clinical superiority and greater patient adherence compared to adapalene monotherapy.     

Pivotal clinical trials of adapalene in the treatment of acne

Adapalene, a naphthoic-acid derivative, possesses some of the biological activities of tretinoin but has distinct physicochemical properties and binding properties for selective affinity for retinoic acid receptors. As such, adapalene is less likely to be associated with certain local tolerability problems (e.g. burning, erythema, pruritus).
Over the past 5 years, numerous clinical trials have been conducted to compare the efficacy and tolerability of adapalene and tretinoin in the treatment of acne vulgaris. Three pivotal, large, well-controlled studies involving almost 900 patients showed that adapalene gel 0.1% and adapalene solution 0.1% are at least as effective as tretinoin gel 0.025%, with superior local tolerability. Adapalene cream 0.1% has proven to be significantly more effective than vehicle, with response rates comparable to those observed with the gel and solution. A meta-analysis of trials with the gel formulation confirmed these findings, showing equivalent efficacy and improved tolerability vs. tretinoin gel 0.025%. Moreover, the onset of clinical effect was shown to be significantly more rapid than that of tretinoin gel. Taken together, these studies demonstrated that adapalene has overall efficacy similar to that of topical tretinoin, but with a superior therapeutic ratio that may result in superior outcomes in clinical practice through improved compliance. This may be expected because of its lesser potential for skin irritation, especially early in treatment, and because of greater convenience in that no waiting period is required between face washing and application of the product. Therefore, 5 years of clinical experience have established that adapalene in its various formulations is a valuable addition to current treatments for acne vulgaris.     

A comparison of the efficacy and tolerability of adapalene 0·1% gel versus tretinoin 0·025% gel in patients with acne vulgaris: a meta-analysis of five randomized trials

The purpose of this meta-analysis was to determine if adapalene 0·1% gel (Differin®) provided superior efficacy and better tolerability than tretinoin 0·025% gel in the treatment of acne vulgaris. All comparative studies, both published and unpublished, from the United States and Europe, that fulfilled rigorous protocol criteria (multicentre, randomized, investigator-blind) were used. Five comparative studies met these criteria. In total, the meta-analysis evaluated 900 patients (450 treated with adapalene 0·1% gel, 450 treated with tretinoin 0·025% gel) with mild-to-moderate acne from the combined clinical trials. To avoid study bias, the meta-analysis used an intention-to-treat analysis. Statistical methodology for the meta-analysis included analysis of covariance, analysis of variance and Cochran–Mantel–Haenszel test. All statistical tests were two-sided, with the 0·05 probability level used to establish statistical significance, and 95% confidence intervals used to assess equivalence. Adapalene demonstrated equivalent efficacy to tretinoin in terms of reducing total lesion count. Adapalene demonstrated more rapid efficacy, as evidenced by a significant difference in the reduction of inflammatory and total lesions at week 1. Adapalene also demonstrated considerably greater local tolerability at all evaluation periods. The findings from this meta-analysis suggest that adapalene 0·1% gel constitutes a pharmacologic advance over such classic retinoids as tretinoin for the treatment of acne vulgaris.     

Comparison of adapalene 0·1% solution and tretinoin 0·025% gel in the topical treatment of acne vulgaris

A multicentre study was conducted to compare clinical safety and efficacy of adapalene 0·1% solution and tretinoin 0·025% gel, both topical treatments for acne, in a once-daily dosage regimen for 12 weeks. A total of 297 patients were enrolled by eight investigators in this randomized, investigator-masked study in a parallel group design. An open label period using adapalene followed this study to assess the long-term safety of adapalene solution.
  Adapalene and tretinoin proved to be clinically and statistically effective in treating acne by reducing inflammatory (47% and 50%, respectively) and non-inflammatory lesions (57% and 54%) as compared to baseline. When comparing patients who had 75% or greater improvement in open comedones, adapalene was shown to be significantly more effective than tretinoin. No serious adverse event was reported during this study, including during the long-term period. The reactions that occurred were similar between treatments, i.e. burning, pruritus, scaling, dryness and erythema.     

Assessment of adapalene gel for the treatment of actinic keratoses and lentigines: a randomized trial

BACKGROUND: Adapalene is a synthetic retinoid with an established clinical efficacy against acne and good local tolerability. Its effectiveness in the treatment of photodamaged skin has not been studied. OBJECTIVE: We sought to determine the safety and efficacy of adapalene gel in the treatment of actinic keratoses and solar lentigines. METHODS: In a prospective, 2-center, randomized, controlled, investigator-masked, parallel-group study, 90 patients with actinic keratoses and solar lentigines were treated daily with either adapalene gel (0.1% or 0.3%) or its vehicle gel for 4 weeks, followed by twice-daily applications, if tolerated, for up to 9 months. RESULTS: Of the 90 Caucasian patients (69 male, 21 female; mean age 63.1 years) who were enrolled into the study, 83 patients completed 9 months of treatment. With adapalene gel 0.1% and 0.3%, the mean number of actinic keratoses was reduced by 0.5 +/- 0.9 (mean +/- SE) and 2.5 +/- 0.9, respectively. Whereas, with the vehicle gel, there was an increase of 1.5 +/- 1.3 (P <.05). After 1 month of treatment, the patients who received adapalene had significant lightening of solar lentigines as compared with the patients who were treated with vehicle gel (P <.05). After 9 months, 57% and 59% of the patients had lighter lesions in the adapalene 0.1% and 0.3% groups, respectively, in comparison with only 36% in the vehicle group (P <.05). Histologic evaluations revealed improved cellular atypia and reduced epidermal melanin in adapalene-, as compared with vehicle-treated group. The differences, however, were not statistically significant. A retrospective evaluation of paired clinical photographs (before and after 9-month treatment) by 2 dermatologists who were treatment-blinded revealed significant improvement in wrinkles and other clinical features of photoaged skin with adapalene as compared with its vehicle. CONCLUSION: Adapalene gel 0.1% and 0.3% were well tolerated and improved actinic keratoses, solar lentigines, and other features of photodamaged skin.     

Evaluation of clinical efficacy and safety of adapalene 0·1% gel versus tretinoin 0·025% gel in the treatment of acne vulgaris, with particular reference to the onset of action and impact on quality of life

A randomized, multicentre, investigator-masked study was conducted in 105 patients with mild to moderate acne vulgaris to compare the efficacy and safety of adapalene 0·1% gel with tretinoin 0·025% gel after three months of treatment, with particular emphasis on reduction in inflammatory lesion counts after one week of treatment and impact on quality of life.
  In terms of efficacy, adapalene gel was found to be superior to tretinoin gel after one week of treatment, with respect to reduction in inflammatory lesion counts (32% vs. 17%, respectively; P  = 0·001), total lesion counts (28% vs. 22%, respectively; P  = 0·042) and global severity grade (28% vs. 16%, respectively; P  = 0·001). No significant difference between the two treatments was found after 12 weeks of treatment for any of these variables. Evaluation of facial skin tolerance parameters showed significant differences between the two treatments in favour of adapalene for dryness, erythema, immediate and persistent burning and pruritus for at least one time point. One patient in the adapalene group and three patients in the tretinoin group experienced medical events which lead to discontinuation of treatment (skin irritation; NS). Quality of life scores improved more rapidly in the adapalene group than in the tretinoin group, with significant differences ( P < 0·05) appearing at week 1 for questions related to problems with partners, close friends or relatives and to skin symptoms. There was also a significantly greater improvement in social and leisure activity in the adapalene group at week 12.
  Adapalene 0·1% gel reduced inflammatory and total lesion counts more rapidly than tretinoin 0·025% gel, and was also better tolerated. These differences appear to result in an earlier and greater quality of life improvement for the patients receiving adapalene.