title: Antimicrobial and antifungal activities of a novel cationic antimicrobial peptide, omiganan, in experimental skin colonisation models.
abstract: Omiganan pentahydrochloride is a novel, synthetic, cationic, antimicrobial peptide that is being developed for the prevention of catheter-related infections and the treatment of acne and rosacea. In this study, the efficacy of topical omiganan gel was evaluated in two skin colonisation models (ex vivo pig skin and in vivo guinea pig skin). When tested in the ex vivo pig skin colonisation model, omiganan 0.1-2% gels exhibited potent dose-dependent activity against gram-positive and gram-negative bacteria and yeasts; the maximum effect was observed at 1-2%. No significant difference was noted in activity toward meticillin-resistant and meticillin-sensitive Staphylococcus aureus, and drug activity was not affected by the inoculum size. The antimicrobial activity of omiganan 1% gel was rapid, with a 2.7 log(10)colony-forming unit (CFU)/site reduction in Staphylococcus epidermidis counts at 1 h post application and a 5.2 log(10)CFU/site reduction at 24 h. Additional studies in the guinea pig skin colonisation model confirmed the potent antimicrobial and antifungal activities of omiganan 1% gel. In conclusion, omiganan gels have been demonstrated to be rapidly bactericidal and fungicidal, with significant dose-dependent activity against a broad spectrum of infectious organisms. These results further confirm that the drug has the potential as a topical antimicrobial agent.
authors.affiliation: MIGENIX Inc., 102-2389 Health Sciences Mall, Vancouver, BC V6T 1Z3, Canada. erubinchik@migenix.com
authors.forename: Evelina
authors.initials: E
authors.lastname: Rubinchik
authors.forename: Dominique
authors.initials: D
authors.lastname: Dugourd
authors.forename: Teresa
authors.initials: T
authors.lastname: Algara
authors.forename: Christopher
authors.initials: C
authors.lastname: Pasetka
authors.forename: H David
authors.initials: HD
authors.lastname: Friedland
mesh_terms: D000287:Administration, Topical; D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D000935:Antifungal Agents / Q000627:therapeutic use*; D023181:Antimicrobial Cationic Peptides / Q000008:administration & dosage / Q000627:therapeutic use*; D001419:Bacteria / Q000187:drug effects* / Q000254:growth & development; D002353:Carrier State / Q000382:microbiology*; D015169:Colony Count, Microbial; D004195:Disease Models, Animal; D005260:Female; D005658:Fungi / Q000187:drug effects* / Q000254:growth & development; D006168:Guinea Pigs; D066298:In Vitro Techniques; D050296:Microbial Viability; D012867:Skin / Q000382:microbiology*; D013552:Swine; D016896:Treatment Outcome
chemical_list: D000900:Anti-Bacterial Agents; D000935:Antifungal Agents; D023181:Antimicrobial Cationic Peptides; C478918:omiganan pentahydrochloride