Tolerability of Topical Antimicrobials in Treatment of Acne Vulgaris
June 2014 | Volume 13 | Issue 6 | Original Article | 658 | Copyright © June 2014
Kyle B. Bartlett MD,a Scott A. Davis MA,a and Steven R. Feldman MD PhDa,b,c
aCenter for Dermatology Research, Department of Dermatology, Wake Forest School of Medicine, Winston-Salem, NC
bDepartment of Pathology, Wake Forest School of Medicine, Winston-Salem, NC
cDepartment of Public Health Sciences, Wake Forest School of Medicine, Winston-Salem, NC
BACKGROUND: Thirty to 40% of patients using topical treatments do not comply with their treatment regimen.
OBJECTIVE: To examine how tolerability is assessed, tolerability ratings, and clinical significance of tolerability ratings of topical antimicrobials for acne.
METHODS: A literature search was performed using the terms “tolerability AND acne AND (benzoyl peroxide OR antimicrobial OR clindamycin OR erythromycin OR dapsone OR sulfur OR sulfacetamide).” Inclusion criteria were: 1) evaluation of tolerability, 2) use of an identified topical antimicrobial for acne treatment without combination retinoid use, 3) an original study, in English.
RESULTS: Thirty-four of 132 articles met the inclusion criteria. Tolerability was measured through subject and investigator assessment of specific tolerability parameters and by reporting of adverse events. Nearly all of the acne treatments were well tolerated. Treatment related study discontinuation rates were low and had little to no relation to the degree of tolerability measures.
LIMITATIONS: Patients may be more adherent in clinical trials than in clinical practice. Differences in the measure used to assess tolerability make comparisons difficult.
CONCLUSIONS: Topical antimicrobial acne therapy is generally well tolerated. Discontinuation rates are low under study conditions. Tolerability of topical antimicrobial therapy for acne may not have great clinical significance. J Drugs Dermatol.
Topical therapy is the most common way to administer acne medication1 and in cases of mild to moderate acne, it is the standard route of treatment.2 There is an increasing number of topical acne treatments available to patients,
but maximum potential efficacy is hindered by a number of factors including bacterial resistance,
and poor compliance.3 At least 30-40% of patients using topical treatments may not comply
with their treatment regimens.4 Tolerability is a potential barrier, but the clinical
significance of tolerability of topical antibiotics for acne is not well characterized.
To assess this we examined how tolerability was measured in different topical antimicrobial
treatments, how tolerable the topical treatments were by these measures, and how this
tolerability affected use of the treatment.5-7
A literature search was performed on pubmed.org on June 8, 2013.
The terms “tolerability AND acne AND (benzoyl peroxide OR antimicrobial
OR clindamycin OR erythromycin OR dapsone OR sulfur OR sulfacetamide)”
were used with “MeSH” terms automatically included in the search. Studies
that evaluated tolerability of an identified topical antimicrobial,
had results separable from any concurrent retinoid use, were original
studies, and were in English were selected. Studies were assessed for
design, what tolerability parameters were evaluated, how
parameters were measured, how often subjects were evaluated, who
the evaluator was, and how many discontinuations occurred due to
treatment related cutaneous tolerability. After recording this
information we then analyzed how tolerable the separate antimicrobials
were according to the published tolerability findings. We determined
clinical significance of tolerability by comparing the measured tolerability
to the percent number of discontinuations in each study.
Data were arranged into groups based on the scoring method used to report the data.
These groups were analyzed separately because conversions between groups could not be made.
Scatter plots were constructed with “x” values derived from the treatment related discontinuations (or more specifically,
cutaneous treatment related discontinuations were specified) for each of the treatment arms; “y”
values were an average across all tolerability parameters for each treatment arm used. Separate
scatter plots were then made for each of the groups by specific tolerability parameter,
again using discontinuations for “x” values, and each group’s average scores in each of
the specific tolerability parameters (eg, erythema) as the “y” values. An equation
for a trendline was then calculated using Microsoft Excel 2007, and R squared (R2)
values were included to ascribe significance to the line.