Date of report 20 Jul 2020
Reported case interaction between
Etravirine and Apixaban
Etravirine and Apixaban
Drugs suspected to be involved in the DDI
Complete list of drugs taken by the patient
apixaban
Clinical case description
50 year man durably suppressed on Truvada and Etravirine (HIV seroconversion in 2003 with V106I RT mutation, intolerant of EFV (CNS disturbance), borderline eGFR 68mls/min. 2019 presented with pleuritic chest pain and breathlessness, CT confirmed extensive bilateral pulmonary emboli. Since unprovoked pulmonary embolism, for lifelong anticoagulation, apixaban started at standard dosing 5mg bd for 1 week, then 2.5mg daily (prescriber unaware of potential DDI with etravirine). HIV team continued apixaban dosing at 5mg bd- heparin concentrations were therapeutic (1.37U/mL). However, dose subsequently dropped to recommended maintenance of 2.5mg daily- heparin concentrations were subtherapeutic at 0.59 U/mL. DDI considered likely, antiretrovirals changed to an integrase regimen.
Clinical Outcome
Drug Interaction Probability Scale (DIPS)
Editorial Comment
Coadministration has not been studied. Apixaban is metabolized by CYP3A4 and to a lesser extent by CYP1A2, CYP2C8, CYP2C9 and CYP2C19. Etravirine could potentially decrease apixaban exposure resulting in diminished efficacy. In this situation, it may be recommended changing cART to unboosted integrase inhibitors, as in the present clinical case.
University of Liverpool Recommendation
Potential interaction - may require close monitoring, alteration of drug dosage or timing of administration