Table 2.

RCTs comparing topical clindamycin versus placebo or vehicle.

Ref	Number of people	Treatment, dose, duration	Results	Comment
	393 people with mild to moderate acne	Clindamycin 1% v benzoyl peroxide 5% v benzoyl peroxide plus clindamycin v vehicle 4 times daily, for 11 weeks	Total lesion count: No data reportedNon-inflammatory lesions: Clindamycin significantly reduced number of non-inflammatory lesions from baseline at 11 weeks compared with vehicle (mean % change: –9% with clindamycin v +11% with vehicle; P = 0.04) Inflammatory lesions: Clindamycin significantly reduced number of inflammatory lesions from baseline at 11 weeks compared with vehicle (mean % reduction: –35% with clindamycin v –5% with vehicle; P less than 0.001)Patient perception of improvement: No data reported Adverse effects: No significant difference in adverse effects (erythema, dryness, peeling, burning, or pruritus) between clindamycin and vehicle (reported as NS, CI not reported)	Pooled data from 1 single-centre and 1 multicentre trial
	108 people with mild to moderate acne	Clindamycin phosphate 1% twice daily v oral tetracycline 500 mg twice daily v placebo, for 8 weeks	Total lesion count: No data reportedNon-inflammatory lesions: No data reported Inflammatory lesions: Mean reduction in inflammatory lesion count from baseline with clindamycin 2.38; P = 0.0001. Mean inflammatory lesion count with placebo 6.24; P = NS, CI not reportedPatient perception of improvement: Proportion of people whose acne had “markedly improved” or “improved” from baseline: 72% with clindamycin; P value not reported. Proportion of people whose acne had “markedly improved” or “improved” from baseline: 3% with placebo; P value not reportedAdverse effects: 1 person using clindamycin, and 1 using placebo had diarrhoea	No direct comparison of topical clindamycin v placebo, as trial designed to compare topical clindamycin v oral tetracycline. Completer analysis in 87 people, no intention-to-treat analysis performed
	135 people with moderate acne	Clindamycin phosphate 1% twice daily v placebo, for 12 weeks	Total lesion count: No data reportedNon-inflammatory lesions: No data reported. Inflammatory lesions: Clindamycin significantly reduced papules at 12 weeks compared with placebo (% reduction: 49% with clindamycin v 24% with placebo; P = 0.05). Clindamycin significantly reduced pustules at 12 weeks compared with placebo (% reduction: 59% with clindamycin v 31% with placebo; P = 0.05) Patient perception of improvement: No data reportedAdverse effects: Clindamycin was associated with burning. 1 person taking clindamycin and 1 taking placebo had diarrhoea	Unblinded
	40 people with mild to moderate acne	Clindamycin phosphate 1% twice daily v vehicle, for 12 weeks	Total lesion count: No data reported Non-inflammatory lesions: No significant difference between clindamycin and vehicle in non-inflammatory lesions at 12 weeks (% reduction in open comedones: 38% with clindamycin v 32% with vehicle; P = NS)Inflammatory lesions: No significant difference between clindamycin and placebo in inflammatory lesions at 12 weeks (% reduction in papules: 22% with clindamycin v 19% with placebo; P = NS; % reduction in pustules: 12% with clindamycin v 22% with placebo; P = NS)Patient perception of improvement: No data reportedAdverse effects: No data reported	Only 76% of people completed the trial, but intention-to-treat analysis performed
	367 people with moderate to severe acne	Clindamycin phosphate 1% v oral tetracycline v placebo, for 8 weeks	Total lesion count: No data reportedNon-inflammatory lesions: No data reportedInflammatory lesions: Clindamycin significantly reduced number of inflammatory lesions at 8 weeks compared with placebo (mean number of papules per person: 8.3 with clindamycin v 11.7 with placebo; P less than 0.05; mean number of pustules: 1.1 v 2.7; P less than 0.05)Patient perception of improvement: Clindamycin significantly increased the proportion of people who thought their acne was “markedly improved” or “improved”: 88% with clindamycin v 57% with placebo; P less than 0.05 Adverse effects: 9 people taking clindamycin and 6 people taking placebo had diarrhoea	Completer analysis in 305/367 [83%] people who completed the trial
	413 people with moderate acne, multicentre	Clindamycin phosphate 1% twice daily v clindamycin hydrochloride 1% twice daily v vehicle, for 8 weeks	Total lesion count: No data reportedNon-inflammatory lesions: No data reportedInflammatory lesions: Clindamycin phosphate or clindamycin hydrochloride significantly reduced number of inflammatory lesions at 8 weeks compared with vehicle (clindamycin phosphate, % reduction in papules: 56% with clindamycin v 42% with vehicle; P = 0.002; % reduction in pustules: 72% with clindamycin v 43% with vehicle; P = 0.029) Patient perception of improvement: Clindamycin significantly increased the proportion of people who rated acne “markedly improved” or “improved” compared with vehicle (77% with clindamycin phosphate v 77% with clindamycin hydrochloride v 56% with vehicle; reported as significant, P value not reported) Adverse effects: 12 people taking clindamycin and 2 people taking placebo had diarrhoea	Completer analysis in 358/413 [87%] people who completed the trial
	46 people with moderate to severe acne	Clindamycin phosphate 1% twice daily v placebo, for 12 weeks	Total lesion count: No significant difference in mean lesion count: between clindamycin and placebo (0.2 with clindamycin v 0.6 with placebo; P = 0.34) Non-inflammatory lesions: No significant difference in the number of non-inflammatory lesions at 12 weeks between clindamycin and placebo (mean number of open comedones per person: 3.3 with clindamycin v 5.2 with placebo; P = 0.49; mean number of closed comedones per person: 3.4 v 5.1; P = 0.47) Inflammatory lesions: Clindamycin significantly reduced number of pustules at 12 weeks compared with placebo, but did not reduce papules (mean number of pustules per person: 1.5 with clindamycin v 3.1 with placebo; P = 0.02; mean number of papules per person at 12 weeks: 6.8 v 10.6; P = 0.16) Patient perception of improvement: No data reported Adverse effects: 3 people taking clindamycin and 5 taking placebo had diarrhoea. 1 person taking clindamycin had burning and 1 had eczema

NS, not significant; Ref, reference