Updated in vivo methods for evaluating topical antimicrobial agents on human skin

Area of Science:

• Microbiology
• Dermatology
• Pharmacology

Background:

• Topical antimicrobial agents require robust efficacy testing.
• Standardized in vivo quantitative methods are crucial for evaluating these agents.
• Assessing antimicrobial performance under various conditions is essential.

Purpose of the Study:

• To present updated and expanded in vivo quantitative testing procedures.
• To determine the efficacy of topical antimicrobial agents.
• To provide reliable methods for evaluating antimicrobial performance on skin.

Main Methods:

• Occlusion test: Measures prevention of microflora expansion under occlusive dressings (24-48 hr).
• Expanded flora test: Assesses suppression of dense microbial populations (6-48 hr or 10 min).
• Persistence test: Evaluates sustained antimicrobial effect and skin reservoir establishment (up to 3 days).
• Ecological shift test: Determines alterations in cutaneous microbial ecology.
• Serum inactivation test: Assesses antimicrobial activity in the presence of serum proteins.

Main Results:

• The described methods provide quantitative data on antimicrobial efficacy.
• Testing procedures are adaptable for agents with different intended uses (e.g., immediate degerming vs. sustained effect).
• The methods allow for assessment of antimicrobial activity under various relevant conditions, including serum presence.

Conclusions:

• The presented in vivo quantitative testing procedures offer a comprehensive framework for evaluating topical antimicrobial agents.
• These updated methods enhance the reliability and scope of efficacy assessments.
• The procedures are valuable for research and development of new antimicrobial products.