INTRODUCTION
Combination therapy for acne, simultaneously targeting
multiple pathogenic factors is now commonplace,1
and many studies have shown that the combination of
clindamycin 1% with benzoyl peroxide (BP) 5% is superior to
each individual active ingredient. As a result, fixed combination
products of clindamycin 1% and BP 5% have seen extensive use
for the treatment of acne vulgaris.2-4 Although these products
are very effective, dryness and irritation from the BP component
are still limiting side effects in some patients.5
Consequently, a fixed-dose, once-daily combination product
containing clindamycin phosphate 1.2% (equivalent to 1%
clindamycin) and a low concentration (2.5%) of BP (clindamycin-
BP 2.5%) was developed to effectively treat both the
inflammatory and non-inflammatory lesions of acne vulgaris,
while minimizing the potential for skin irritation.6
Clindamycin-BP 2.5% is an alcohol-free aqueous gel with a
humectant and solubilizing properties that may enhance both
delivery and bioavailability of the micronized BP and clindamycin
phosphate into the pilosebaceous unit. A combination of
lower BP concentration and this formulation provided a fixed
combination product shown to be effective and well tolerated
in moderate to severe acne.6
A post-hoc analysis showed greater efficacy in moderate acne
patients compared to severe patients.7 It was postulated that BP
concentrations might be increased using the same formulation
to provide greater effectiveness in those moderately severe
acne patients, without significantly impacting safety and tolerability.
This article reports the findings of a well-controlled trial
of this higher BP strength formulation.
METHODS
Study Design
The study received approval before patient enrollment from the
appropriate institutional review board for each center. It was
conducted in accordance with the Declaration of Helsinki and
Good Clinical Practices (GCP) and in compliance with local regulatory
requirements. All patients provided written informed
consent before entering the study.
This was a multicenter, randomized, double-blind, vehicle-controlled,
parallel group study in 498 patients with moderate to
