Oritavancin (Orbactiv) is a new-generation synthetic lipoglycopeptide that is used as a single injection for the treatment of acute bacterial skin and soft-tissue infections.

Oritavancin Uses:

• Acute bacterial skin and skin structure infections:

  • It is used for treating adult patients having acute bacterial skin and skin structure infections (ABSSSI) caused by susceptible isolates of the following gram-positive microorganisms:
    • Staphylococcus aureus (including methicillin-susceptible and methicillin-resistant isolates)
    • Streptococcus pyogenes
    • Streptococcus agalactiae
    • Streptococcus dysgalactiae, Streptococcus anginosus group (including S. anginosus, S. intermedius, S. constellatus)
    • Enterococcus faecalis (vancomycin-susceptible isolates only)

Oritavancin (Orbactiv) Dose in Adults

Oritavancin (Orbactiv) Dose in the treatment of Acute bacterial skin and skin structure infections (ABSSI):

• IV: 1,200 mg as a stat dose.

Use in Children:

Not studied in children.

Pregnancy Risk Factor C

• In animal reproduction studies, no adverse events were observed.

Use during breastfeeding:

• It is unknown if the drug is excreted from breast milk.
• It is recommended that nursing women be cautious when administering the medication.

Dose in Kidney Disease:

• CrCl ≥30 mL/minute:

  • Dosage adjustment not necessary.

• CrCl <30 mL/minute:

  • No dosage adjustments have been provided in the manufacturer’s labeling (has not been studied).

• ESRD requiring hemodialysis:

  • No dosage adjustments have been provided in the manufacturer’s labeling (has not been studied)
  • It is not removed by hemodialysis.

Dose in Liver Disease:

• Mild to moderate hepatic impairment (Child-Pugh class A or B):

  • Dosage adjustment not necessary.

• Severe hepatic impairment (Child-Pugh class C):

  • No dosage adjustments have been provided in the manufacturer’s labeling (has not been studied).

Side Effects of Oritavancin (Orbactiv):

• Cardiovascular:

  • Tachycardia
  • Hypersensitivity Angiitis
  • Peripheral Edema

• Central Nervous System:

  • Headache
  • Dizziness

• Dermatologic:

  • Erythema Multiforme
  • Pruritus
  • Skin Rash
  • Urticaria

• Endocrine & Metabolic:

  • Hyperuricemia
  • Hypoglycemia

• Gastrointestinal:

  • Nausea
  • Vomiting
  • Diarrhea

• Hematologic & Oncologic:

  • Anemia
  • Eosinophilia

• Hepatic:

  • Increased Serum ALT
  • Increased Serum AST
  • Increased Total Serum Bilirubin

• Hypersensitivity:

  • Angioedema
  • Hypersensitivity Reaction

• Infection:

  • Abscess

• Local:

  • Injection Site Phlebitis
  • Injection Site Reaction
  • Erythema At Injection Site
  • Extravasation
  • Induration At Injection Site

• Neuromuscular & Skeletal:

  • Myalgia
  • Osteomyelitis
  • Tenosynovitis

• Respiratory:

  • Bronchospasm
  • Wheezing

Contraindications to Oritavancin (Orbactiv):

• Hypersensitivity to oritavancin, or any other component of this formulation
• Use of IV UFH (unfractionated heparin) for 5 days after administration of the drug (it causes false elevation of aPTT for up to 5 days after administration)

Warnings and precautions

• Hypersensitivity

  • There have been reports of severe hypersensitivity reactions (median onset in studies was 1.2 days).
  • If there is an acute reaction, it is important to stop the infusion immediately and provide supportive care (median resolution: 2.4 days).
  • Patients with a history glycopeptide allergy should be asked about any hypersensitivity reactions they have had in the past.

• Infusion reactions

  • Reports of infusion-related reactions including urticaria, pruritus, and flushing have been made.
  • If there is a reaction, you can interrupt or slow down infusion.

• Osteomyelitis

  • Patients treated with oritavancin had more osteomyelitis cases in clinical trials.
  • Patients should be monitored for osteomyelitis signs and symptoms and, if necessary, provide alternate antibacterial treatment.

• Superinfection

  • Oritavancin may cause fungal or bacterial superinfection. This includes C. difficile associated diarrhea(CDAD) and pseudomembranous collitis (CDAD).
  • These cases have been reported more than 2 months after treatment.

Oritavancin: Drug Interaction

Note: Drug Interaction Categories:

• Risk Factor C: Monitor When Using Combination
• Risk Factor D: Consider Treatment Modification
• Risk Factor X: Avoid Concomitant Use

Monitoring Parameters:

• Baseline renal functions (serum urea nitrogen, creatinine) & liver function tests (AST, ALT, bilirubin).
• Patients should be monitored for any kind of infusion-related reactions i.e pruritus, urticaria, flushing, signs & symptoms of osteomyelitis & hypersensitivity reactions (especially in patients with known glycopeptide allergy).

How to administer Oritavancin (Orbactiv)?

• Intravenous: Infuse over three hours.
• If a common IV line is being used for the administration of other drugs in addition to oritavancin, flush the IV line before and after each infusion with dextrose water.
• If an infusion-related reaction i.e pruritus, urticaria, flushing occurs, consider interrupting or slowing infusion.

Mechanism of action of Oritavancin (Orbactiv):

• It is a lipoglycopeptide having a concentration-dependent bactericidal activity.
• It inhibits cell wall biosynthesis by binding to stempeptides of peptidoglycan precursors.
• This inhibits cross-linking by binding bridging segments and by disrupting integrity of the bacterial membrane.

Protein binding:

• 85%

Metabolism:

• metabolized

Half-life elimination:

• About 245 hours

Excretion:

• Excreted in feces and urine as unchanged drug (less than 1% in feces & 5% in urine, over 2 weeks  after administration)

International Brand Names of Oritavancin:

• Orbactiv

Oritavancin Brand Names in Pakistan:

No Brands Available in Pakistan.