Zolav^®: a new antibiotic for the treatment of acne

Abstract

Background

Acne is a prominent skin condition affecting >80% of teenagers and young adults and ~650 million people globally. Isotretinoin, a vitamin A derivative, is currently the standard of care for treatment. However, it has a well-established teratogenic activity, a reason for the development of novel and low-risk treatment options for acne.

Objective

To investigate the effectiveness of Zolav^®, a novel antibiotic as a treatment for acne vulgaris.

Materials and methods

Minimum inhibitory concentration of Zolav^® against Propionibacterium acnes was determined by following a standard protocol using Mueller-Hinton broth and serial dilutions in a 96-well plate. Cytotoxicity effects on human umbilical vein endothelial cells and lung cells in the presence of Zolav^® were investigated by determining the growth inhibition (GI₅₀) concentration, total growth inhibition concentration, and the lethal concentration of 50% (LC₅₀). The tryptophan auxotrophic mutant of Escherichia coli strain, WP2 uvrA (ATCC 49979), was used for the AMES assay with the addition of Zolav^® tested for its ability to reverse the mutation and induce bacterial growth. The in vivo effectiveness of Zolav^® was tested in a P. acnes mouse intradermal model where the skin at the infection site was removed, homogenized, and subjected to colony-forming unit (CFU) counts.

Results

Susceptibility testing of Zolav^® against P. acnes showed a minimum inhibitory concentration of 2 µg/mL against three strains with no cytotoxicity and no mutagenicity observed at the highest concentrations tested, 30 µM and 1,500 µg/plate, respectively. The use of Zolav^® at a concentration of 50 µg/mL (q8h) elicited a two-log difference in CFU/g between the treatment group and the control.

Conclusion

This study demonstrates the potential of Zolav^® as a novel treatment for acne vulgaris.

Keywords:

• acne
• MscL
• Zolav^®
• benzoyl peroxide
• isotretinoin
• antibiotic resistance

View correction statement:

Zolav®: a new antibiotic for the treatment of acne [Corrigendum]

Supplementary materials

Figure S1 Comparison of infection area between treated and untreated mice.

Notes: Pictures of mice from the untreated group (A and B) and Zolav^® at 50 µg/mL q8h (C and D) treated group at 26 hours (A and C) and at 50 hours (B and D) after challenge.

Table S1 Activity of Zolav^® on revertant colonies of Escherichia coli in the absence of S9

Table S2 Summary of Propionibacterium acnes intradermal infection model in mice in CFU/g (log10)

Acknowledgments

The authors gratefully acknowledge funding from Boulos & Cooper Pharmaceuticals Pty Ltd for supporting the project. Zolav^® is a trademark fully registered in Australia.

Disclosure

RAB is the Chief Executive Officer of Boulos & Cooper Pharmaceuticals Pty Ltd, which owns the intellectual property, and AD is consulting for Boulos & Cooper Pharmaceuticals Pty Ltd. The authors report no other conflicts of interest in this work.