Evaluation of pharmacist-prescribed nirmatrelvir/ritonavir for patients with COVID-19

Authorization of nirmatrelvir/ritonavir expanded outpatient treatment options for those with coronavirus disease 2019 (COVID-19), but prescribing of the medication is complex. The objective of this study was to evaluate the appropriateness of nirmatrelvir/ritonavir prescribing through a pharmacist-driven service as compared to usual care.

This was a retrospective cohort study. Patients prescribed nirmatrelvir/ritonavir by a pharmacist between May 1 and December 31, 2022, were temporally matched to those who received nirmatrelvir/ritonavir through usual care. The primary outcome was the percentage of patients appropriately prescribed nirmatrelvir/ritonavir by meeting criteria related to authorization-specific requirements, assessment of hepatic and renal function, and management of drug interactions. Descriptive and inferential statistics were performed.

There were 106 patients in each cohort (N = 212). Patients were mainly female (n = 135, 63.7%) and 65 years of age or older (n = 117, 55.2%). All study-defined criteria for appropriate nirmatrelvir/ritonavir prescribing were met in 88.7% of patients (n = 94) who received care through the pharmacist-driven service, as compared to 41.5% of patients (n = 44) managed through usual care (P < 0.0001). In both groups nirmatrelvir/ritonavir was consistently prescribed within 5 days of symptom onset (P > 0.999) and to patients with a qualifying comorbid condition (P = 0.498). However, hepatic (P = 0.030) and renal (P = 0.024) laboratory values were more likely to be current when the prescription arose from a pharmacist as opposed to the usual care process. Drug interactions also were more likely to be identified and mitigated by pharmacists (P < 0.0001).

Nirmatrelvir/ritonavir was appropriately prescribed by pharmacists in most cases, demonstrating that pharmacists can support safe and effective use of nirmatrelvir/ritonavir for patients with complex comorbidities and medication regimens.