Clinical and bacteriological evaluation of nadifloxacin 1% cream versus erythromycin 4% gel in the treatment of mild-to-moderate facial acne vulgaris: A randomized study

Antibiotics have been the mainstay of inflammatory acne treatment for years. However, antibiotic and especially the erythromycin-resistant propionibacteria have been isolated with an increased frequency, resulting in treatment failure. Therefore, new antibiotics with a good efficacy and tolerability, and a low potential for the development of resistant bacterial species, are in need for the future success of acne therapy. The aim of this study was to evaluate the clinical and bacteriological efficacy and safety of nadifloxacin 1% cream versus erythromycin 4% gel in the treatment of facial acne vulgaris. A total of 100 patients (age range: 14-30 years) with mild-to-moderate facial acne vulgaris were randomized to receive nadifloxacin 1% cream (Group I) or erythromycin 4% gel (Group II) twice daily for 12 weeks. All the patients were also prescribed tretinoin 0.05% cream twice weekly. Both groups were compared regarding the lesion counts, global acne grading score, the subject self-assessment and the investigator's global assessment of the therapy, and the adverse effects. The growth ratios of Propionibacterium acnes and Staphylococcus epidermidis were evaluated. Also, the bacterial antibiotic resistance was assessed by using the minimum inhibitory concentration values of nadifloxacin and erythromycin. Both treatments caused significant similar reductions in all types of acne lesion counts and the global acne grading scores by week 12. The treatment satisfaction in Group I was better than the one in Group II. However, no difference was observed between the two groups in the respect of the investigator ratings. Microbiological evaluation revealed no significant differences regarding the growth ratios of Propionibacterium acnes and Staphylococcus epidermidis in both groups. The erythromycin resistant Propionibacterium acnes and Staphylococcus epidermidis, and the nadifloxacin resistant Propionibacterium acnes colonizations were similar in both groups. The growth ratios of Staphylococcus epidermidis were significantly decreased, though the nadifloxacin resistant Staphylococcus epidermidis colonization was significantly higher in Group I at week 12. Both treatments were well-tolerated, and all the adverse effects were mild and similar, yet erythromycin associated with increased skin dryness and peeling. We conclude that nadifloxacin 1% cream is as efficacious and safe as erythromycin 4% gel in the treatment of mild-to-moderate facial acne vulgaris. Although nadifloxacin's antibacterial efficacy against Staphylococcus epidermidis is partially better than erythromycin, it may cause the development of resistant species.