Cost-Effective Rationale for Antimicrobial Therapy
Title: Randomised controlled multiple treatment
comparison to provide a cost-effective rationale for the selection
of antimicrobial therapy in acne
Authors: Ozolins M, et al.
Publication: Health Technol Assess. 2005 Jan;9(1):iii-212.
The authors tested 649 people between the ages of 12 and 39 years
with mild to moderate facial acne. They randomly assigned these
people into five groups treated with:
- 500 mg oral oxytetracycline antibiotics twice a day
- 100 mg oral Minocin MR (minocycline) antibiotics once daily
- Topical benzamycin (3% erythromycin + 5% benzoyl peroxide)
- Topical Stiemycin (2% erythromycin), topical Panoxyl Aquagel
(5% benzoyl peroxide)
- Topical Panoxyl Aquagel (5% benzoyl peroxide)
Since this was a blind study, the groups that received oral medications
were also given blank creams, whereas those that receive just
the topical medications were also given blank or placebo pills.
The treatments were given for 18 weeks and the results were checked
at 0, 6, 12, and 18 weeks.
The authors found that the best improvement was seen with the
two combination topical medications (erythromycin plus benzoyl
peroxide), followed by benzoyl peroxide alone, oxytetracycline,
and minocycline. For all regimens, the largest reduction in acne
severity was seen in the first 6 weeks. Nevertheless, the authors
noted that the use of these antimicrobial treatments to treat
acne is not optimal, as only half to two-third of patients showed
improvements. At the end of the study, 95% of the patients have
residual acne. After extending the treatment to 12 weeks, the
benefits only increased slightly. 55% of the patients require
further treatment after 18 weeks.
The authors found that because of the cost of medications, benzoyl
peroxide was the most cost effective, whereas minocycline was
the least cost-effective treatment. If oral antibiotics were to
be given, doctors can choose oxytetracycline since it has similar
efficacy but just one-seventh the cost.
The two topical erythromycin regiments that produce the best
results seem to be equally effective in patients with erythromycin-resistant
acne causing propionibacteria, as compared to patients without
the drug-resistant bacteria. This was not true for tetracycline-resistant
bacteria, as the efficacy of tetracycline was far lower for patients
with these types of bacteria.
Side effects were more common in patients that took oral antibiotics,
whereas local irritation was more common for those treated topically,
especially with benzoyl peroxide.