Pharmacist Involvement in Managing Drug-drug Interactions (DDIs) for Hepatitis C Virus (HCV)-infected Patients on Direct-acting Antiviral Agent (DAA): A Multicentre Cohort Study (P-DAA Study)

Introduction: HCV infection has led to high mortality and morbidity rates, highlighting the need for immediate measures to contain and eradicate infection while providing optimal care to infected patients who may present with various comorbidities. Pharmacists play a crucial role in managing drug-drug interactions that exist with medications to treat comorbidities and DAAs. Method: A prospective cohort study was conducted among patients who received DAAs at 17 Ministry of Health (MOH) facilities. Following the screening, the obtainment of consent, and recruitment, details on demographic background, comorbidities, type of HCV infection, and treatment, along with medication reconciliation, were performed. A simple and multiple logistic regression was performed to determine factors associated with DDI occurrence. Results: A total of 404 patients were recruited. Out of 291 patients (72%) who received at least one co-medication, drug-drug interactions (DDIs) were reported in 174 patients (59.8%). DDI with Amlodipine was the most common (n=77, 36.2%). Out of 213 DDI detected, 208 (97.7%) were categorized as moderate interaction. The number of comorbidities and the number of comedications were significantly associated with the occurrence of DDIs Conclusion: Pharmacists play a key role in managing drug-drug interactions in HCV patients. With the high incidence of interaction observed in this study, it is crucial to manage individually since comorbidities vary with patients. As such, eradication of HCV infection can be undertaken with less opportunity of treatment failure.