Thiostrepton

Summary

Thiostrepton is a naturally occurring cyclic thiopeptide antibiotic produced by Streptomyces azureus. It is primarily used in veterinary medicine as a topical antibiotic for treatment of skin and ear infections, often formulated in combination with other agents. It has demonstrated activity against Gram-positive bacteria and has been investigated for anti-cancer and anti-protozoal properties.

Mechanism of Action

Inhibits bacterial protein synthesis by binding to the GTPase-associated center of the 23S rRNA of the 50S ribosomal subunit, blocking elongation factor G (EF-G) and elongation factor Tu (EF-Tu) interactions, thereby halting translocation and peptide chain elongation.

Routes of Administration

Goals & Uses

• Anti-protozoal activity (malaria)Antiparasitic / ResearchLow
• Treatment of bacterial skin and ear infections (veterinary)Antimicrobial / VeterinaryHigh
• Anticancer activity via FOXM1 inhibitionOncology / ResearchLow

Contraindications

• Application to perforated tympanic membraneAnatomicalModerate
• Known hypersensitivity to thiostrepton or thiopeptide antibioticsAllergyHigh

Adverse Effects

• Local skin irritationDermatologicalUncommon
• Hypersensitivity reactionImmunologicRare

Drug Interactions

• Other aminoglycoside or ototoxic agents (otic use)Moderate

Population Constraints

• Humans (systemic use)Species/RouteAbsolute
• Pregnant animalsReproductiveRelative

Regulatory Status

• European UnionApprovedApproved: Veterinary topical antibioticAuthorized for veterinary use in several EU member states in combination formulations.
• United StatesApprovedApproved: Veterinary topical treatment of skin and ear infections in dogs and catsApproved by the FDA for veterinary use only; found in combination products such as Panalog.
• United KingdomApprovedApproved: Veterinary topical antibioticAvailable in veterinary combination products post-Brexit under VMMD authorization.

Approved in the US and other jurisdictions for veterinary use (topical). Not approved for systemic human use due to poor oral bioavailability and insolubility. Investigated in research settings for anticancer activity via FOXM1 inhibition.

Evidence & Sources

No sources recorded yet.