Pilot Randomized-Control Trial to Assess the Effect Product Sampling has on Adherence Using Adapalene/Benzoyl Peroxide Gel in Acne Patients

February 2014 | Volume 13 | Issue 2 | Original Article | 135 | Copyright © February 2014

Laura F. Sandoval DO,a Ashley Semble MS,a Cheryl J. Gustafson MD,a Karen E. Huang MS,a Michelle M. Levender MD,a and Steven R. Feldman MD PhDa,b,c

aDepartment of Dermatology, Center for Dermatology Research, 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: The treatment of acne can be difficult, with suboptimal adherence resulting in poor treatment outcomes.
PURPOSE: To determine whether demonstrating to patients how to properly apply a topical acne medication through the use of a sample product will improve adherence.
METHODS: Subjects with mild to moderate acne were instructed to use adapalene/benzoyl peroxide gel once daily for six weeks. Subjects were randomized into sample or no sample group. Sample group received a demonstration on how to apply the medication using a product sample. The primary outcome was median adherence, recorded using electronic monitoring, and secondary outcomes were efficacy measures including the Acne Global Assessment (AGA) and lesion counts and the Perceived Medical Condition Self-Management Scale (PMCSMS).
RESULTS: Data from 17 patients was collected and analyzed. Median adherence rates were 50% in the sample group and 35% in the no sample group (p=0.67). The median percent improvement in non-inflammatory lesions were 46% for the sample group and 33% for the no-sample group (p=0.10).
LIMITATIONS: The small size of this pilot study limited the extent of subgroup analyses.
CONCLUSIONS: Objective electronic monitoring expanded our previous observations of poor adherence in the treatment of acne. There is a considerable potential effect size on adherence for the use of samples, supporting the need for future, well powered studies to assess the value of using samples in the treatment of acne and other dermatologic skin diseases.

J Drugs Dermatol. 2014;13(2):135-140.


Acne is a common condition, which affects most people at some point in their lifetime, including approximately 85% of adolescents.1 In addition to physical effects of acne, such as potential for permanent scarring, acne can also have a significant negative impact on psychological, social and emotional well-being, at times resulting in social phobias, withdrawal from society, and clinical depression.2;3 Dermatologists have a wide range of acne treatments available, which are efficacious in clinical trials, however, these treatments tend to be significantly less effective in clinical practice.4
The gap between efficacy in clinical trials compared to clinical practice may be caused by differences in treatment adherence. 5 Factors affecting adherence behavior are multifactorial and include patients’ motivation to get well, the strength of the doctor-patient relationship, the complexity of the medication regimen, and medication side effects.6;7 For a patient to be adherent to treatment, it is critical that they understand how to properly use their medication. This is particularly true in treatment of dermatologic conditions, in which patients are often using topical medications. Proper use of topical medications is more challenging to communicate than in the case of oral medications, in which a patient simply needs to understand when to take their pill. With topical medications, applying the proper amount of medication is critical: too much medicine can result in wasted medication and side effects effecting tolerability, while too little medicine may reduce efficacy.
Patients who are well educated about their disease and how to appropriately treat it are more likely to adhere to a treatment regime.7;8 The aim of this study is to determine whether providing acne patients with a sample of adapalene/benzoyl peroxide gel and then using that sample to demonstrate how to properly apply topical acne medication, will improve adherence and consequently, improve treatment outcomes.


This was a single-centered, investigator-blinded, parallel armed randomized control trial to primarily assess if instructing subjects with acne how to use adapalene/benzoyl peroxide by using