Quinupristin

Streptogramin B Antibiotic (cyclic Depsipeptide)Rx: PrescriptionCompound: Approved

Also known as: Pristinamycin IA derivative, Quinupristin/dalfopristin, RP 57669, Synercid

Educational Only — Not medical advice. Consult a qualified clinician before using any peptide.

Summary

Quinupristin is a semisynthetic streptogramin B cyclic depsipeptide antibiotic derived from pristinamycin IA. It is used exclusively in a fixed 30:70 combination with dalfopristin (Synercid) for the treatment of serious or life-threatening infections caused by vancomycin-resistant Enterococcus faecium (VREF) and complicated skin and skin structure infections due to Staphylococcus aureus and Streptococcus pyogenes. The combination is bactericidal against staphylococci and streptococci.

Mechanism of Action

Binds irreversibly to the 50S ribosomal subunit (23S rRNA), blocking the exit tunnel for nascent polypeptides and inhibiting the late phase of protein synthesis; used in combination with dalfopristin (streptogramin A), which acts synergistically by altering the ribosome conformation to enhance quinupristin binding.

Routes of Administration

Intravenous

Goals & Uses

  • Complicated skin and skin structure infections (cSSSI)AntibacterialHigh
  • Nosocomial pneumonia due to Gram-positive organismsAntimicrobial / Infectious DiseaseLow
  • Treatment of vancomycin-resistant Enterococcus faecium (VREF) infectionsAntimicrobial / Infectious DiseaseHigh
  • MRSA infections (off-label)Antimicrobial / Infectious DiseaseModerate

Contraindications

  • Concurrent use of drugs metabolized by CYP3A4 with narrow therapeutic indexDrug InteractionHigh
  • Hypersensitivity to quinupristin, dalfopristin, or other streptograminsAllergyHigh

Adverse Effects

  • Infusion site reactions (pain, inflammation, thrombophlebitis)LocalCommon
  • Nausea and vomitingGastrointestinalCommon
  • Arthralgia and myalgiaMusculoskeletalCommon
  • Elevated hepatic transaminases (AST/ALT)HepaticUncommon
  • QT prolongationCardiovascularRareExtended QT interval on ECG
  • HyperbilirubinemiaHepaticCommon

Drug Interactions

  • CyclosporineHigh
  • QT-prolonging agents (e.g., cisapride, terfenadine)High
  • HMG-CoA reductase inhibitors (statins metabolized by CYP3A4)Moderate
  • TacrolimusHigh

Population Constraints

  • Hepatic impairmentOrgan FunctionRelative
  • Pediatric patientsAgeRelative
  • Patients on multiple CYP3A4-metabolized drugsPolypharmacyRelative
  • Pregnancy (Category B)PregnancyRelative

Regulatory Status

  • European UnionApprovedApproved: Infections due to vancomycin-resistant Enterococcus faecium, Nosocomial pneumonia, Skin and soft tissue infections caused by Gram-positive bacteriaApproved by EMA; marketed as Synercid in Europe for serious Gram-positive infections where other antibiotics are unsuitable.
  • United StatesApprovedApproved: Vancomycin-resistant Enterococcus faecium (VREF) bacteremia and associated serious infections, Complicated skin and skin structure infections due to S. aureus (MSSA) or S. pyogenesApproved by FDA in 1999 (accelerated approval for VREF). Marketed as Synercid. Orphan drug designation for VREF.
  • United KingdomApprovedApproved: Vancomycin-resistant Enterococcus faecium infections, Complicated skin and skin structure infectionsPreviously approved under EMA authorization; post-Brexit status follows UK licensing. Niche use in resistant Gram-positive infections.

Approved by the FDA in 1999 under accelerated approval for VREF infections. Marketed as Synercid (quinupristin/dalfopristin 30:70 w/w). Requires central venous catheter administration due to venous irritation with peripheral infusion.

Evidence & Sources

No sources recorded yet.

Browse All PeptidesBuild My Stack