Page data last changed: . Chemistry registry snapshot: . Registry refreshes and identity assessments are separate from scientific content review.
A tryptophan-rich 12-residue analog of indolicidin studied as a topical antiseptic gel.
Also known as: MBI 226 · MX-226 · CLS001
Part of the Foundational & therapeutic peptides cluster
Overview
Omiganan is a synthetic 12-amino-acid cationic peptide analog of indolicidin, a host-defense peptide from bovine neutrophils. It depolarizes bacterial membranes and has broad activity against bacteria and yeasts, and it has been investigated as a topical gel for catheter-site antisepsis and inflammatory skin conditions such as rosacea and atopic dermatitis. This page is educational and not medical advice.
Source & context
Biological / chemical source: Synthetic analog of indolicidin (bovine neutrophil host-defense peptide)
Primary research or clinical context: Investigational topical agent studied for skin infections and inflammatory skin conditions
Sequence and action
Omiganan (ILRWPWWPWRRK, formulated as the pentahydrochloride) is rich in tryptophan and arginine, favoring insertion at the membrane interface. Against Staphylococcus aureus it depolarizes the cytoplasmic membrane, causing rapid, concentration-dependent killing of Gram-positive and Gram-negative bacteria and Candida species.
Clinical investigation
Topical omiganan progressed through trials for prevention of catheter-associated infections and was later explored for rosacea, acne and atopic dermatitis, where it can shift the skin microbiome. It has not received marketing approval and is discussed here for educational context only.
Sequence
One-letter sequence commonly cited for Omiganan (educational; isoforms and modifications may differ):
ILRWPWWPWRRK
Residues plotted ~100° apart around an α-helix — clustering of one color reveals an amphipathic face.
Structure & chemistry
Molecular identity & reference confidence
Source-supported reference
Reference values are taken from the cited molecular record or curated profile. A database match is not independent laboratory verification; modifications, counter-ions, and formulations can change the measured mass.
- Molecular form
- Omiganan (source record; form not independently established)
- Species
- Not established by this molecular identity audit
- Termini (N / C)
- Not specified / Not specified
Average reference mass
Reference policy updated: 2026-10-05
- IUPHAR/BPS source snapshot · 2026-10-01
- PubChem molecular record · 2026-10-01
- Molecular formula
- C90H127N27O12
- Average reference mass
- ≈ 1,779.1
- PubChem CID: 16131445
- IUPHAR ligand: 14110
- ChEMBL: CHEMBL1615933
- DrugBank: DB06610
- CAS RN: 204248-78-2
- UNII: 618SLL9VBS
Chemistry values: PubChem, IUPHAR/BPS Guide to Pharmacology · fetched 2026-10-01.
Clinical development snapshot
ClinicalTrials.gov lists 14 registered studies with “Omiganan” as an intervention (snapshot 2026-10-01). A registry footprint is not evidence of efficacy or approval.
| NCT | Title | Phase | Status | Updated |
|---|---|---|---|---|
| NCT02547441 | Study to Evaluate the Safety and Efficacy of a Once-Daily CLS001 Topical Gel Versus Vehicle | Phase 3 | completed | 2022-08-02 |
| NCT02576860 | Study to Evaluate the Safety and Efficacy of a Once-Daily CLS001 Topical Gel Versus Vehicle | Phase 3 | completed | 2022-08-02 |
| NCT02576847 | Study to Evaluate the Long-term Safety of a Once-Daily Omiganan Topical Gel | Phase 3 | completed | 2022-07-19 |
| NCT03688971 | Omiganan Twice a Day (BID) in Patients With Facial Seborrheic Dermatitis | Phase 2 | unknown | 2019-05-01 |
| NCT03091426 | Pharmacodynamics of Omiganan BID in Patients With Atopic Dermatitis | Phase 2 | completed | 2017-12-27 |
| NCT02596074 | Pharmacodynamics, Safety/Tolerability and Efficacy of Topical Omiganan in Patients With uVIN | Phase 2 | completed | 2017-08-03 |
Omiganan — reconstitution calculator
Enter how much peptide is in the vial and how much diluent (e.g. bacteriostatic water) is added. The tool returns the resulting solution concentration — and, for any amount you type, the volume it corresponds to. This is educational arithmetic, not a dosing recommendation.
Reference form: Omiganan (source record; form not independently established)Average reference mass: 1,779.1 Da
Enter an amount to see the volume it corresponds to.
Educational concentration mathematics only. This tool does not recommend a dose, amount, or protocol, and nothing here is medical advice. Many peptides are not authorized by Health Canada for human use — see our reconstitution and bacteriostatic-water guides for context.
FAQ about Omiganan
What is Omiganan?+
Omiganan is a synthetic 12-amino-acid cationic peptide analog of indolicidin, a host-defense peptide from bovine neutrophils. It depolarizes bacterial membranes and has broad activity against bacteria and yeasts, and it has been investigated as a topical gel for catheter-site antisepsis and inflammatory skin conditions such as rosacea and atopic dermatitis. This page is educational and not medical advice.
What Canadian product status is recorded for Omiganan?+
Canadian product status for Omiganan has not been verified in this profile. No verified record here does not mean no authorization exists. Status depends on the product, formulation and use; consult Health Canada's product records.
What is the typical length of Omiganan?+
Omiganan is commonly described as approximately 12 amino acids (Synthetic antimicrobial peptide (indolicidin analog)).
Related peptides
References & further reading
- 1.Rousel et al. (2023). Treatment with the Topical Antimicrobial Peptide Omiganan in Mild-to-Moderate Facial Seborrheic Dermatitis versus Ketoconazole and Placebo: Results of a Randomized Controlled Proof-of-Concept Trial. Int J Mol Sci
- 2.Niemeyer-van der Kolk et al. (2020). Omiganan Enhances Imiquimod-Induced Inflammatory Responses in Skin of Healthy Volunteers. Clin Transl Sci
- 3.Anderegg et al. (2004). Quality control guidelines for MIC susceptibility testing of omiganan pentahydrochloride (MBI 226), a novel antimicrobial peptide. J Clin Microbiol
- 4.Żyrek et al. (2021). The Antimicrobial Activity of Omiganan Alone and In Combination against Candida Isolated from Vulvovaginal Candidiasis and Bloodstream Infections. Antibiotics (Basel)
- 5.Ng et al. (2017). Preliminary investigations into developing all-D Omiganan for treating Mupirocin-resistant MRSA skin infections. Chem Biol Drug Des
- 6.Sader et al. (2004). Omiganan pentahydrochloride (MBI 226), a topical 12-amino-acid cationic peptide: spectrum of antimicrobial activity and measurements of bactericidal activity. Antimicrob Agents Chemother
- 7.Fritsche et al. (2008). Antimicrobial activity of omiganan pentahydrochloride against contemporary fungal pathogens responsible for catheter-associated infections. Antimicrob Agents Chemother
- 8.Melo et al. (2007). Omiganan interaction with bacterial membranes and cell wall models. Assigning a biological role to saturation. Biochim Biophys Acta
- 9.PubChem — compound summary for Omiganan (CID 16131445)
- 10.PMC — Omiganan pentahydrochloride (MBI 226): spectrum of antimicrobial activity