Date of report: 13 May 2019
Reported case interaction between
Atazanavir and Omeprazol

FLS Science

Drugs suspected to be involved in the DDI

Drug A
Atazanavir (Victim)
Daily Dose
300 (mg)
Dose adjustment performed
No
Administration Route
Oral
Start date
April 30, 2013
End date
Ongoing
Drug B
Omeprazol (Perpetrator)
Daily Dose
20 (mg)
Dose adjustment performed
No
Administration Route
Oral
Start date
Unknown
End date
Ongoing

Complete list of drugs taken by the patient

Antiretroviral treatment
Ritonavir
Raltegravir
Atazanavir (with Ritonavir or Cobicistat)
Complete list of all comedications taken by the patient, included that involved in the DDI
Omeprazol, lormetazepam

Clinical case description

Gender
Male
Age
58
eGFR (mL/min)
>60
Liver function impairment
Yes
Child-Pugh
Child-Pugh A
Description
Patient with VHC coinfection and liver cirrhoses. Diagnosed with gastric ulcer and diverticulitis requiring treatment with omeprazol with doses between 20 and 40 mg/day. No loss of efficacy of ATV/R observed. He presented episodes of hyperbilirubinemia but currently the levels are normal. Current viral load: undetectable

Outcome

No unwanted outcome

Editorial Comment

Coadministration of atazanavir with proton pump inhibitors is not recommended. Administration of omeprazole (40 mg once daily) decreased atazanavir Cmax, AUC and Cmin by 96%, 94% and 95%, respectively when given 2 h before atazanavir (400 mg, once daily). If coadministration is judged unavoidable, close clinical monitoring is recommended and doses of omeprazole should not exceed 20 mg and must be taken approximately 12 hours prior to the atazanavir.