A multicentre, randomized, single‐blind comparison of topical clindamycin 1%/benzoyl peroxide 5% once‐daily gel versus clindamycin 1% twice‐daily gel in the treatment of mild to moderate acne vulgaris in Chinese patients

Efficacy of topical treatments for mild-to-moderate acne: A systematic review and meta-analysis of randomized control trials

Acne is a common skin condition, but little data exist on the comparative efficacy of topical acne therapies. We conducted a systematic review and network meta-analysis to evaluate the efficacy of topical therapies for mild-to-moderate acne. Searches in PubMed/MEDLINE, Cochrane CENTRAL via Ovid, Embase via Ovid and Web of Science were conducted on 29 November 2021. Randomized controlled trials examining ≥12 weeks of topical treatments for acne vulgaris in subjects aged 12 and older were included. Main outcomes were absolute or percent change in acne lesion count and treatment success on the Investigator's Global Assessment scale. Thirty-five randomized clinical trials with 33,472 participants comparing nine different topical agents were included. Adapalene-benzoyl peroxide (BPO), clindamycin-BPO and clindamycin-tretinoin demonstrated the greatest reduction in non-inflammatory (ratio of means [RoM] 1.76; 95% CI [1.46; 2.12], RoM 1.70; 95% CI [1.44; 2.02] and RoM 1.87; 95% CI [1.53; 2.30], respectively), inflammatory (RoM 1.56; 95% CI [1.44; 1.70], RoM 1.49; 95% CI [1.39; 1.60] and RoM 1.48; 95% CI [1.36; 1.61], respectively) and total lesion count (ROM 1.67; 95% CI [1.47; 1.90], RoM 1.59; 95% CI [1.42; 1.79] and RoM 1.64; 95% CI [1.42; 1.89], respectively) compared to placebo. All single agents outperformed placebo except tazarotene, which did not significantly outperform placebo for inflammatory and non-inflammatory lesion count reduction. Most combination agents significantly outperformed their individual components in lesion count reduction and global assessment scores, except for clindamycin-tretinoin and clindamycin-BPO, which did not significantly outperform tretinoin (RoM 1.13; 95% CI [0.94; 1.36]) and BPO (RoM = 1.15, 95% CI [0.98; 1.36]), respectively, for non-inflammatory lesion reduction. There was no significant difference amongst most single agents when evaluating lesion count reduction. Combination agents are generally most effective for mild-to-moderate acne; however for non-inflammatory acne, the addition of clindamycin in topical regimens is unnecessary and should be avoided.

Acne Vulgaris-Novel Treatment Options and Factors Affecting Therapy Adherence: A Narrative Review

Acne vulgaris is an extremely common skin condition, affecting a large population of adolescents, but at the same time, remaining a quite common issue in the group of adult patients. Its complex pathogenesis includes increased sebum secretion, impaired follicular keratinization, colonization of sebaceous glands with Cutibacterium acne bacteria, and the development of inflammation in pilosebaceous units. Although there are many methods of treatment available targeting the mechanisms mentioned above, a large percentage of patients remain undertreated or non-compliant with treatment. Ineffective treatment results in the formation of acne scars, which has a major impact on the well-being and quality of life of the patients. The aim of this publication was a review of available evidence on widely used and novel methods of topical and systemic treatment of acne, additionally including current literature-based analysis of factors affecting patients' compliance. The strengths and limitations of novel substances for treating acne were discussed. We conclude that an effective acne treatment remains a challenge. A better understanding of current treatment options and factors affecting patients' compliance could be a helpful tool in choosing a proper treatment option.

Topical preparations for the treatment of mild-to-moderate acne vulgaris: systematic review and network meta-analysis

BACKGROUND

Acne is very common and can have a substantial impact on wellbeing. Guidelines suggest first-line management with topical treatments, but there is little evidence regarding which treatments are most effective.

OBJECTIVES

To identify the most effective and best tolerated topical treatments for acne using network meta-analysis.

METHODS

CENTRAL, MEDLINE, Embase and World Health Organization Trials Registry were searched from inception to June 2020 for randomized trials that included participants with mild/moderate acne. Primary outcomes were self-reported improvement in acne, and trial withdrawal. Secondary outcomes included change in lesion counts, Investigator's Global Assessment, change in quality of life and total number of adverse events. Network meta-analysis was undertaken using a frequentist approach. Risk of bias was assessed using the Cochrane Risk of Bias Tool and confidence in evidence was assessed using CINeMA.

RESULTS

A total of 81 papers were included, reporting 40 trials with a total of 18 089 participants. Patient Global Assessment of Improvement was reported in 11 trials. Based on the pooled network estimates, compared with vehicle, benzoyl peroxide (BPO) was effective (35% vs. 26%) for improving self-reported acne. The combinations of BPO with adapalene (54% vs. 35%) or with clindamycin (49% vs. 35%) were ranked more effective than BPO alone. The withdrawal of participants from the trial was reported in 35 trials. The number of patients withdrawing owing to adverse events was low for all treatments. Rates of withdrawal were slightly higher for BPO with adapalene (2·5%) or clindamycin (2·7%) than BPO (1·6%) or adapalene alone (1·0%). Overall confidence in the evidence was low.

CONCLUSIONS

Adapalene in combination with BPO may be the most effective treatment for acne but with a slightly higher incidence of withdrawal than monotherapy. Inconsistent reporting of trial results precluded firmer conclusions.

Topical benzoyl peroxide for acne

BACKGROUND

Acne is a common, economically burdensome condition that can cause psychological harm and, potentially, scarring. Topical benzoyl peroxide (BPO) is a widely used acne treatment; however, its efficacy and safety have not been clearly evaluated.

OBJECTIVES

To assess the effects of BPO for acne.

SEARCH METHODS

We searched the following databases up to February 2019: the Cochrane Skin Specialised Register, CENTRAL, MEDLINE, Embase, and LILACS. We also searched five trials registers and checked the reference lists of relevant randomised controlled trials (RCTs) and systematic reviews.

SELECTION CRITERIA

We included RCTs that compared topical BPO used alone (including different formulations and concentrations of BPO) or as part of combination treatment against placebo, no treatment, or other active topical medications for clinically diagnosed acne (used alone or in combination with other topical drugs not containing BPO) on the face or trunk.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures as expected by Cochrane. Primary outcome measures were 'participant global self-assessment of acne improvement' and 'withdrawal due to adverse events in the whole course of a trial'. 'Percentage of participants experiencing any adverse event in the whole course of a trial' was a key secondary outcome.

MAIN RESULTS

We included 120 trials (29,592 participants randomised in 116 trials; in four trials the number of randomised participants was unclear). Ninety-one studies included males and females. When reported, 72 trials included participants with mild to moderate acne, 26 included participants with severe acne, and the mean age of participants ranged from 18 to 30 years. Our included trials assessed BPO as monotherapy, as add-on treatment, or combined with other active treatments, as well as BPO of different concentrations and BPO delivered through different vehicles. Comparators included different concentrations or formulations of BPO, placebo, no treatment, or other active treatments given alone or combined. Treatment duration in 80 trials was longer than eight weeks and was only up to 12 weeks in 108 trials. Industry funded 50 trials; 63 trials did not report funding. We commonly found high or unclear risk of performance, detection, or attrition bias. Trial setting was under-reported but included hospitals, medical centres/departments, clinics, general practices, and student health centres. We reported on outcomes assessed at the end of treatment, and we classified treatment periods as short-term (two to four weeks), medium-term (five to eight weeks), or long-term (longer than eight weeks). For 'participant-reported acne improvement', BPO may be more effective than placebo or no treatment (risk ratio (RR) 1.27, 95% confidence interval (CI) 1.12 to 1.45; 3 RCTs; 2234 participants; treatment for 10 to 12 weeks; low-certainty evidence). Based on low-certainty evidence, there may be little to no difference between BPO and adapalene (RR 0.99, 95% CI 0.90 to 1.10; 5 RCTs; 1472 participants; treatment for 11 to 12 weeks) or between BPO and clindamycin (RR 0.95, 95% CI 0.68 to 1.34; 1 RCT; 240 participants; treatment for 10 weeks) (outcome not reported for BPO versus erythromycin or salicylic acid). For 'withdrawal due to adverse effects', risk of treatment discontinuation may be higher with BPO compared with placebo or no treatment (RR 2.13, 95% CI 1.55 to 2.93; 24 RCTs; 13,744 participants; treatment for 10 to 12 weeks; low-certainty evidence); the most common causes of withdrawal were erythema, pruritus, and skin burning. Only very low-certainty evidence was available for the following comparisons: BPO versus adapalene (RR 1.85, 95% CI 0.94 to 3.64; 11 RCTs; 3295 participants; treatment for 11 to 24 weeks; causes of withdrawal not clear), BPO versus clindamycin (RR 1.93, 95% CI 0.90 to 4.11; 8 RCTs; 3330 participants; treatment for 10 to 12 weeks; causes of withdrawal included local hypersensitivity, pruritus, erythema, face oedema, rash, and skin burning), erythromycin (RR 1.00, 95% CI 0.07 to 15.26; 1 RCT; 60 participants; treatment for 8 weeks; withdrawal due to dermatitis), and salicylic acid (no participants had adverse event-related withdrawal; 1 RCT; 59 participants; treatment for 12 weeks). There may be little to no difference between these groups in terms of withdrawal; however, we are unsure of the results because the evidence is of very low certainty. For 'proportion of participants experiencing any adverse event', very low-certainty evidence leaves us uncertain about whether BPO increased adverse events when compared with placebo or no treatment (RR 1.40, 95% CI 1.15 to 1.70; 21 RCTs; 11,028 participants; treatment for 10 to 12 weeks), with adapalene (RR 0.71, 95% CI 0.50 to 1.00; 7 RCTs; 2120 participants; treatment for 11 to 24 weeks), with erythromycin (no participants reported any adverse events; 1 RCT; 89 participants; treatment for 10 weeks), or with salicylic acid (RR 4.77, 95% CI 0.24 to 93.67; 1 RCT; 41 participants; treatment for 6 weeks). Moderate-certainty evidence shows that the risk of adverse events may be increased for BPO versus clindamycin (RR 1.24, 95% CI 0.97 to 1.58; 6 RCTs; 3018 participants; treatment for 10 to 12 weeks); however, the 95% CI indicates that BPO might make little to no difference. Most reported adverse events were mild to moderate, and local dryness, irritation, dermatitis, erythema, application site pain, and pruritus were the most common.

AUTHORS' CONCLUSIONS

Current evidence suggests that BPO as monotherapy or add-on treatment may be more effective than placebo or no treatment for improving acne, and there may be little to no difference between BPO and either adapalene or clindamycin. Our key efficacy evidence is based on participant self-assessment; trials of BPO versus erythromycin or salicylic acid did not report this outcome. For adverse effects, the evidence is very uncertain regarding BPO compared with adapalene, erythromycin, or salicylic acid. However, risk of treatment discontinuation may be higher with BPO compared with placebo or no treatment. Withdrawal may be linked to tolerability rather than to safety. Risk of mild to moderate adverse events may be higher with BPO compared with clindamycin. Further trials should assess the comparative effects of different preparations or concentrations of BPO and combination BPO versus monotherapy. These trials should fully assess and report adverse effects and patient-reported outcomes measured on a standardised scale.

Topical treatments for acne

Topical drugs have been used successfully to treat acne for decades. This review discusses the use, efficacy, and safety of options available via prescription. Topical antibiotics, dapsone, benzyl peroxide, azelaic acid, and topical retinoids are included. Topical antibiotics should not be used as monotherapy but rather be combined with other agents to avoid resistant Propionibacterium acnes strains. Benzoyl peroxide is effective in preventing bacteria resistance. Topical retinoids address primarily the comedonal but also the inflammatory lesions of acne. Azelaic acid is useful in treating acne lesions and for lightening postinflammatory hyperpigmentation that may accompany inflammatory acne lesions. Combinations of agents that address different aspects of acne pathogenesis may offer higher benefit to acne patients.