Antimicrobial · Investigational
Pexiganan (MSI-78)
No lawful US pathway
01 · Overview
Pexiganan is a 22-amino acid synthetic analog of magainin 2. It is a cationic membrane-active peptide with broad-spectrum antibacterial activity, and it was developed as pexiganan acetate cream, a topical agent for mildly infected diabetic foot ulcers (PMID 18990064).
Its design was intended to improve potency and stability relative to the parent magainin sequence. It is not approved by the FDA, and no pexiganan product appears in FDA drug approval records.
02 · Research summary & key findings
Two consecutive double-blind controlled trials randomized 835 patients with mildly infected diabetic foot ulcers to topical pexiganan cream or oral ofloxacin; one study failed to demonstrate equivalence, while the second study and the pooled data showed equivalent clinical improvement, microbiological eradication and wound healing rates (PMID 18990064). Rates of worsening cellulitis and amputation did not differ between arms, and no significant resistance to pexiganan emerged, whereas ofloxacin resistance did emerge in some patients (PMID 18990064). Despite these results, pexiganan has not been approved by the FDA and no currently active development program was identified.
03 · Regulatory status
Pexiganan (MSI-78) is in the investigational stage. While preclinical and early-phase data exist, it has not received regulatory approval for clinical use in the United States.
No lawful pathway today
Pexiganan (MSI-78) is not FDA-approved and does not currently have a lawful prescription or compounding pathway in the United States, so we do not sell it and will not book a consultation for it. That can change: in 2026 FDA began reviewing several peptides for compounding.
See the 3 FDA-approved compounds in Antimicrobial
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04 · Administration routes
- Topical
References
- [1]Topical versus systemic antimicrobial therapy for treating mildly infected diabetic foot ulcers: a randomized, controlled, double-blinded, multicenter trial of pexiganan cream Clin Infect Dis, 2008. PMID 18990064
Primary literature
- PubMed: "Pexiganan"
Peer-reviewed literature indexed by the National Library of Medicine.
- ClinicalTrials.gov: "Pexiganan"
Registered interventional and observational studies, including status and phase.
- PubChem: "Pexiganan"
Chemical structure, molecular properties, and bioactivity data.
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