RIVAROXABAN

Structure/Class
  1. Novel oral anti-coagulant (NOAC)
Pharmacodynamics
  1. Direct inhibitor of Factor Xa (therefore inhibiting the common pathway of coagulation)
    • 10000x higher affinity for factor Xa than Factor Xia, IXa, VIIa and IIa.
Absorption/administration
  1. PO – rapidly absorbed with bioavailability of 80%
Distribution
  1. Strongly protein bound (92-95%)

 
Metabolism
  1. Hepatic, via CYP systems.
  2. T ½ of 8 hours, increased to 12 hours in the elderly.
Excretion
  1. 1/3 of the drug is excreted unchanged in the urine
  2. The metabolites are inactive and cleared by faecal and renal routes.
Indications
  1. Treatment of DVT and PE
  2. Prevention of venous thromboembolism in adults after major orthopaedic surgery (THR and TKR)
  3. Prevention of stroke in non-valvular AF
Contraindications
  1. Active bleeding
  2. Any potential for serious life-threatening bleeding
Interactions
  1. With inhibitors and inducers of CYP systems
Special precautions
  1. Renal impairment
    • Drug accumulates in renal impairment leading to increased risk of bleeding.
    • Requires dose adjustment
  2. Hepatic impairment
    • Contraindicated in severe hepatic disease (Childs-Pugh class B and C) due to impaired clearance and underlying coagulopathy.
Adverse effects
  1. Haemorrhage
Dosing/administration
  1. 15-20mg if GFR >30, 10mg if GFR between 15-30 and CI if GFR <15.
  2. Regular monitoring not necessary due to predictable PK. However, does increase both aPTT and PT.
Toxicology
  1. Bleeding
    • Cease drug
    • Requires reversal with PCC (Prothrombinex) or Recombinant factor VII (NovoSeven).
    • FFP also may be useful.
    • Will require specialist input from haematology service.
Withdrawal states
Special notes .