OBJECTIVES: In April 2022, nirmatrelvir/ritonavir (Paxlovid^®) became available for use in Ireland for the acute treatment of coronavirus disease 2019 (COVID-19) in specific circumstances. Paxlovid® is associated with complex drug-drug interactions; this study outlines the steps required to promote its safe utilisation.

METHODS: We analysed the steps undertaken by several organisations to support the safe and effective use of Paxlovid^® in the primary care setting in Ireland. We also evaluated the number of Paxlovid^® enquiries to the National Medicines Information Centre (NMIC).

RESULTS: Under the governance of the Health Services Executive (HSE):

• the HSE COVID-19 Therapeutics Advisory Group provided clinical advice and recommendations on the use of existing and emerging COVID-19 therapeutics, including Paxlovid^® and made recommendations on patient eligibility for treatment.
• HSE stakeholders in collaboration with the Irish College of General Practitioners published a Paxlovid^® summary document to support prescribing in the primary care (and wider community) setting.
• the HSE-Medicines Management Programme (MMP) were requested to undertake a stewardship role for Paxlovid^® and lead communications with practitioners.
• the NMIC established a new service to assist general practitioners (GPs) with drug interaction enquiries specific to the prescribing of Paxlovid^® (including a weekend support service for the first 22 weeks of Paxlovid^® availability). The NMIC and MMP developed a template to enable GPs to submit medication lists for a drug-drug interaction review. Between 15/04/2022 and 11/06/2024, the NMIC received 510 Paxlovid^® enquiries, 439 (86%) of which related to drug-drug interactions, involving a total of 4,547 co-existing medicines.

CONCLUSIONS: Paxlovid^® is known to present a high-risk for drug interactions with commonly dispensed medicines, and a significant amount of work was required to ensure continued optimal prescriber knowledge as this treatment became available for use in Ireland. Collaborations within the HSE and external agencies allowed for timely dissemination of information supporting safe and effective use of Paxlovid^®.