Date of report: 06 May 2019
Reported case interaction between
Dolutegravir and Oxcarbazepine

FLS Science

Drugs suspected to be involved in the DDI

Drug A
Dolutegravir (Victim)
Daily Dose
50 (mg)
Dose adjustment performed
No
Administration Route
Oral
Start date
May 8, 2018
End date
Ongoing
Drug B
Oxcarbazepine (Perpetrator)
Daily Dose
600 (mg)
Dose adjustment performed
No
Administration Route
Oral
Start date
Jan. 1, 2017
End date
Ongoing

Complete list of drugs taken by the patient

Antiretroviral treatment
Dolutegravir/Abacavir/Lamivudine
Complete list of all comedications taken by the patient, included that involved in the DDI
Quetiapine, Risperidone, Olanzapine, Mirtazapine

Clinical case description

Gender
Male
Age
41
eGFR (mL/min)
>60
Liver function impairment
No
Description
HIV-infected patint diagnosed with depressive psychosis. On stable cARt with DTG/ABC/3TC since May 2018. Since 2017 on psychiatric treatment including oxcarbazepine 600 mg qd. Desptite the possibility of decreased dolutegravir exposure due to induction of UGT1A1 and CYP3A by oxcarbazepine HIV viral load in plasma persistently undetectable (<40 copies/mL). No blips.

Outcome

No unwanted outcome

Editorial Comment

Coadministration has not been studied but is expected to decreased dolutegravir exposure due to induction of UGT1A1 and CYP3A by oxcarbazepine. The US Prescribing Information advises to avoid coadministration due to insufficient data to make dosing recommendations. However, the European SPC suggests that dolutegravir be dosed at 50 mg twice daily, but recommends that alternative combinations should be used where possible in INSTI-resistant patients.