Date of report 30 May 2024
Reported case interaction between
Rilpivirine and CLARITHROMYCIN
Rilpivirine and CLARITHROMYCIN
Drugs suspected to be involved in the DDI
Complete list of drugs taken by the patient
Ceftriaxone
Clinical case description
A 57-year-old male with HIV has been on dolutegravir/rilpivirine treatment for 2 years, maintaining virological suppression and immunological control. He presented to the emergency department with a 4-day history of fatigue, weakness, and persistent fever. At the emergency department, he was diagnosed with pneumonia and admitted for treatment with ceftriaxone 2 g every 24 hours intravenously and clarithromycin 500 mg every 12 hours orally. On the fourth day of treatment with clarithromycin, he was evaluated by the HIV Unit, presenting a normal electrocardiogram and no clinical consequences. A decision was made to discontinue clarithromycin.
Clarithromycin is a strong inhibitor of CYP3A4, known to inhibit the metabolism of certain medications, including rilpivirine. This can potentially lead to increased levels of rilpivirine in the bloodstream, which may increase the risk of adverse effects, including prolongation of the QTc interval. Therefore, caution should be exercised when combining clarithromycin with rilpivirine, and close monitoring for any signs of QTc prolongation or other adverse effects is recommended. Alternative antibiotics, such as azithromycin, that do not interact with rilpivirine should be considered.
The use of macrolides along with rilpivirine should be given high consideration due to the potential adverse events related to QTc prolongation.
Clinical Outcome
Editorial Comment
Clarithromycin is a potent inhibitor of CYP3A4. Concomitant administration with rilpivirine may elevate RPV plasma concentrations, potentially increasing the risk of QTc interval prolongation. However, QTc interval prolongation has been associated with supratherapeutic doses of RPV. Achieving equivalent rilpivirine concentrations through interaction with clarithromycin is improbable. Nonetheless, it is advisable to perform an ECG when coadministering clarithromycin and RPV to monitor for potential QTc interval prolongation.
Consider alternatives such as azithromycin.
University of Liverpool Recommendation
Potential interaction - may require close monitoring, alteration of drug dosage or timing of administration