Sofosbuvir + Velpatasvir

Generic Details

Generic Name

Sofosbuvir-Velpatasvir

Other Names

  • Epclusa

Drug Class

  • Direct-acting antiviral (DAA)

Chemical Formula

C49H54N8O8

Molecular Weight

883.01 g/mol

Mechanism of Action

  • Sofosbuvir inhibits the HCV NS5B RNA-dependent RNA polymerase essential for viral replication, while Velpatasvir is an NS5A inhibitor preventing viral replication and assembly.

Indications

  • Treatment of chronic hepatitis C virus (HCV) infection in adults

Common Dosage Forms

  • Tablet

Typical Dosage

  • 400mg sofosbuvir/100mg velpatasvir once daily with or without food for 12 weeks

Pediatric Dosage

  • Safety and efficacy not established in pediatric patients

Geriatric Dosage

  • Dose adjustment not usually necessary in the elderly

Side Effects

  • Headache
  • Fatigue
  • Nausea
  • Insomnia
  • Anemia
  • Rash

Contraindications

  • Concomitant use with rifampin
  • Severe renal impairment
  • Pregnancy

Pregnancy Category

  • Category B - Animal reproduction studies have failed to demonstrate a risk to the fetus and there are no adequate and well-controlled studies in pregnant women.

Lactation Safety

  • Limited data available; caution advised

Drug Interactions

  • Avoid concomitant use with strong P-gp inducers or moderate to strong inducers of CYP2B6 or CYP3A4

Overdose Symptoms

  • No specific overdose symptoms reported

Antidote for Overdose

  • No specific antidote; manage overdose symptomatically

Storage Conditions

  • Store at 25°C (77°F); excursions permitted to 15-30°C (59-86°F)

Pharmacokinetics

  • Absorption: Rapid and high bioavailability
  • Distribution: Protein binding: 61-65% for sofosbuvir, >99.5% for velpatasvir
  • Metabolism: Sofosbuvir is metabolized to its active metabolite GS-461203; Velpatasvir undergoes extensive hepatic metabolism
  • Excretion: Mainly through urine (sofosbuvir) and feces (velpatasvir)

Precautions

  • Monitor for hepatotoxicity
  • Monitor renal function
  • Isolated cases of decompensation of liver disease reported

Warnings

  • Risk of Hepatitis B virus reactivation in co-infected patients
  • Risk of symptomatic bradycardia when co-administered with amiodarone

Others

  • Treatment duration and dosage may vary based on HCV genotype and patient characteristics