Saquinavir, Invirase, SQV

  • Indications
  1. HIV Infection (as part of combination therapy)
  • Contraindications
  1. Age <16 years
  2. QTc Prolongation (or risk)
    1. See below
  • Mechanism
  • Dosing
  1. General
    1. Used in combination with Ritonavir, in addition to other Antiretrovirals
    2. Tablets contain lactose
    3. If taken without food, may have no antiviral activity
      1. Take within 2 hours after a full meal
      2. Meals increase absorption and decrease GI upset
  2. Adult and age >16 years (all regimens should include Ritonavir)
    1. Start: Saquinavir 500 mg orally twice daily AND Ritonavir 100 mg orally twice daily for 7 days, THEN
    2. Next: Saquinavir 1000 mg orally twice daily AND Ritonavir 100 mg orally twice daily
  • Adverse Effects
  1. Rash
  2. Hyperprolactinemia (rare)
  3. Electrocardiogram changes
    1. Obtain EKG at baseline and 3-4 days after starting medication
    2. QTc Prolongation (rare Torsades de Pointes)
      1. Avoid if QTc Prolongation at baseline, congenital Long QT, Hypokalemia, Hypomagnesemia
      2. Stop if QTc increases >20 msec over baseline
    3. PR Prolongation (first degree AV Block)
      1. Second and third degree AV Block is rare
      2. Avoid if risk of complete Heart Block
      3. Caution with agents that prolong PR (e.g. Beta Blockers, Calcium Channel Blockers)
  • Safety
  1. Avoid in Lactation
  2. Avoid in pregnancy (despite pregnancy category B status)
  • Drug Interactions
  1. Multiple Drug Interactions
    1. See Protease Inhibitor
    2. As with other Protease Inhibitors, check a formal Drug Interaction application before prescribing
  2. Rilpivirine
    1. Stop Rilpivirine at least 2 weeks before starting Saquinavir
  3. Medication Causes of QTc Prolongation
    1. See Drug-Induced QTc Prolongation
  4. Garlic supplements (do not use with Saquinavir)
    1. Reduces Saquinavir concentrations by 50%
    2. Levels may remain reduced even after stopiing Garlic
    3. Piscitelli (2002) Clin Infect Dis 34:234-8 [PubMed]
  5. Statins
    1. Atorvastatin dose limited to 20 mg
    2. Rosuvastatin dose limited to lowest effective dose
  6. Opioids
    1. Methadone dose may need to be increased
  7. Clarithromycin
    1. Decrease Clarithromycin dose if Creatinine Clearance <60 ml/min
  8. Digoxin
    1. Monitor levels
  • Efficacy
  1. Weak effect and may worsen resistance for better Protease Inhibitors
    1. Requires high doses that may not be tolerated (lower doses may be ineffective)