Date of report: 20 Jul 2021
Reported case interaction between
Ritonavir and Anabolic Steroids

FLS Science

Drugs suspected to be involved in the DDI

Drug A
Ritonavir (Perpetrator)
Daily Dose
100 (mg)
Dose adjustment performed
No
Administration Route
Oral
Start date
Unknown
End date
April 27, 2021
Drug B
Anabolic Steroids
Daily Dose
Unknown
Dose adjustment performed
No
Administration Route
Oral
Start date
April 13, 2021
End date
April 28, 2021

Complete list of drugs taken by the patient

Antiretroviral treatment
Raltegravir
Tenofovir-DF
Darunavir (with Ritonavir or Cobicistat)
Complete list of all comedications taken by the patient, included that involved in the DDI
Osta Max bodybuilding supplement (Ostarine)

Clinical case description

Gender
Male
Age
45
eGFR (mL/min)
>60
Liver function impairment
No
Description
Acute drug-induced liver injury (DILI), with ALT rising to >1500, AST to 181 IU/L. Liver function tests normalized after discontinuing Osta Max. Osta Max contains ostarine- a selective androgen receptor modulator, which is a UGT and CYP 3a substrate.

Outcome

Toxicity

Drug Interaction Probability Scale (DIPS)

Score
8 - Probable

Editorial Comment

Ostarine is a UGT and CYP 3a substrate. Inhibition of CYPs by RTV may increase the risk of drug-induced liver injury, as it happened in this patient.