▴ Pexiganan acetate (MSI 78) is a synthetic cationic peptide (22 amino acids) with antibacterial activity. It is an analogue of magainin 2, which is a host defence peptide isolated from frog skin.
▴ The drug is thought to act by disturbing the permeability of the cell membrane or cell wall.
▴ Pexiganan acetate has good in vitro activity against Gram-positive and Gram-negative aerobes; 99% of strains were susceptible to the agent using a break-point of 64 mg/L. 89 to 97% of anaerobes were susceptible to pexiganan acetate using the same break-point.
▴ After 7 passages in vitro, there was no evidence of resistance to pexiganan acetate among 2 strains of Staphylococcus aureus.
▴ In 2 phase III multicentre randomised double-blind trials in diabetic patients with infected foot ulcers, both topical pexiganan acetate 1% and oral ofloxacin 800 mg/day achieved clinical cure or improvement in about 90% of patients.
▴ Eradication of pathogens in the 2 studies was achieved in 82% of ofloxacin recipients and 66% of pexiganan acetate recipients at the end of therapy.
▴ Limited data indicate that pexiganan acetate is well tolerated.
KeywordsAdis International Limited Ofloxacin Minimum Inhibitory Concentration Mupirocin Frog Skin
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