May 24, 2017
Recommended Topic Related To:


"The U.S. Food and Drug Administration today approved Differin Gel 0.1% (adapalene), a once-daily topical gel for the over-the-counter (OTC) treatment of acne. Differin Gel 0.1% is approved for use in people 12 years of age and older.



Acanya Gel


Mechanisms Of Action

Clindamycin: Clindamycin is a lincosamide antibacterial [See Microbiology].

Benzoyl Peroxide: Benzoyl peroxide is an oxidizing agent with bacteriocidal and keratolytic effects but the precise mechanism of action is unknown.


The systemic absorption of clindamycin was investigated in an open-label, multiple-dose trial in 16 adult subjects with moderate to severe acne vulgaris treated with 1 gram of ACANYA Gel applied to the face once daily for 30 days. Twelve subjects (75%) had at least one quantifiable clindamycin plasma concentration above the lower limit of quantification (LOQ = 0.5 ng/mL) on Day 1 or Day 30. On Day 1, the mean (± standard deviation) peak plasma concentration (Cmax) was 0.78 ± 0.22 ng/mL (n=9 with measurable concentrations), and the mean AUC0-t was 5.29 ± 0.81 (n=4). On Day 30, the mean Cmax was 1.22 ± 0.88 ng/mL (n=10), and the mean AUC0-t was 8.42 ± 6.01 (n=6). Clindamycin plasma concentrations were below LOQ in all subjects at 24 hours post-dose on the three tested days (Day 1, 15, and 30).

Benzoyl peroxide has been shown to be absorbed by the skin where it is converted to benzoic acid.


Clindamycin binds to the 50S ribosomal subunits of susceptible bacteria and prevents elongation of peptide chains by interfering with peptidyl transfer, thereby suppressing bacterial protein synthesis.

Clindamycin and benzoyl peroxide individually have been shown to have in vitro activity against Propionibacterium acnes, an organism which has been associated with acne vulgaris; however, the clinical significance of this activity against P. acnes is not known.

P. acnes resistance to clindamycin has been documented. Resistance to clindamycin is often associated with resistance to erythromycin.

Clinical Studies

The safety and efficacy of once daily use of ACANYA Gel were assessed in two 12-week multi-center, randomized, blinded trials in subjects 12 years and older with moderate to severe acne vulgaris. The two trials were identical in design and compared ACANYA Gel to clindamycin in the vehicle gel, benzoyl peroxide in the vehicle gel, and the vehicle gel alone.

The co-primary efficacy variables were:

  1. Mean absolute change from baseline at week 12 in
    • Inflammatory lesion counts
    • Non-inflammatory lesion counts
  2. Percent of subjects who had a two grade improvement from baseline on an Evaluator's Global Severity (EGS) score.

The EGS scoring scale used in all of the clinical trials for ACANYA Gel is as follows:

Grade Description
Clear Normal, clear skin with no evidence of acne vulgaris
Almost Clear Rare non-inflammatory lesions present, with rare non-inflamed papules (papules must be resolving and may be hyperpigmented, though not pink-red)
Mild Some non-inflammatory lesions are present, with few inflammatory lesions (papules/pustules only; no nodulocystic lesions)
Moderate Non-inflammatory lesions predominate, with multiple inflammatory lesions evident: several to many comedones and papules/pustules, and there may or may not be one small nodulo-cystic lesion
Severe Inflammatory lesions are more apparent, many comedones and papules/pustules, there may or may not be a few nodulocystic lesions
Very Severe Highly inflammatory lesions predominate, variable number of comedones, many papules/pustules and many nodulocystic lesions

The results of Trial 1 at week 12 are presented in Table 2:

Table 2: Trial 1 Results

Trial 1 ACANYA Gel
N = 399
Clindamycin Gel
N = 408
Benzoyl Peroxide Gel
N = 406
Vehicle Gel
N = 201
EGSS Clear or Almost Clear 115 (29%) 84 (21%) 76 (19%) 29 (14%)
2 grade reduction from baseline 131 (33%) 100 (25%) 96 (24%) 38 (19%)
Inflammatory Lesions:
  Mean absolute change 14.8 12.2 13 9
  Mean percent (%) reduction 55.00% 47.10% 49.30% 34.50%
Non-Inflammatory Lesions:
  Mean absolute change 22.1 17.9 20.6 13.2
  Mean percent (%) reduction 45.30% 38.00% 40.20% 28.60%

The results of Trial 2 at week 12 are presented in Table 3:

Table 3: Trial 2 Results

Trial 2 ACANYA Gel
N = 398
Clindamycin Gel
N = 404
Benzoyl Peroxide Gel
N = 403
Vehicle Gel
N = 194
EGSS Clear or Almost Clear 113 (28%) 94 (23%) 94 (23%) 21 (11%)
2 grade reduction from baseline 147 (37%) 114 (28%) 114 (28%) 27 (14%)
Inflammatory Lesions:
  Mean absolute change 13.7 11.3 11.2 5.7
  Mean percent (%) reduction 54.20% 45.30% 45.70% 23.30%
Non-Inflammatory Lesions:
  Mean absolute change 19 14.9 15.2 8.3
  Mean percent (%) reduction 41.20% 34.30% 34.50% 19.20%

Last reviewed on RxList: 3/3/2017
This monograph has been modified to include the generic and brand name in many instances.

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