Impact of clinical pharmacist-led interventions on early intravenous-to-oral antibiotic switching in patients with community-acquired pneumonia at a Vietnamese hospital

Abstract

Aim/Background: The inappropriate or prolonged use of intravenous (IV) antibiotics increases healthcare costs and hospitalization time. Early switching from IV to oral (PO) antibiotics has been proven to be clinically effective and cost-saving in many settings. This study aimed to evaluate the cost-effectiveness of switching from IV-to-PO antibiotics in the treatment of community-acquired pneumonia (CAP). Materials and Methods: A randomized controlled clinical trial was conducted from June 2024 to August 2025 on patients aged over 18 years who were diagnosed with community-acquired pneumonia (CAP) and received intravenous antibiotic therapy for at least two consecutive days in the Internal Medicine Department of Hoan My Dong Nai Hospital. Information on patient characteristics, antibiotic use, length of hospital stay, and treatment outcomes was obtained from electronic medical records (EMR). Participants were randomly assigned to either a control group or an intervention group. Patients in the control group received standard care without clinical pharmacist involvement. In the intervention group, IV-to-PO antibiotic switch guidelines were introduced to physicians, and clinical pharmacists provided feedback on cases eligible for early switching. The impact of the pharmacist-led interventions was assessed by comparing primary outcomes (rate of appropriate early switching and cost-effectiveness) and secondary outcomes (clinical and laboratory treatment outcomes) between the two study periods. Results: A total of 111 patients were included (55 in control group and 56 in intervention group). The appropriate early switch rate from IV-to-PO therapy was significantly higher in intervention group compared with control group (71.4% vs 3.6%, p < 0.001). The duration of IV antibiotic use and hospital stay were significantly shorter in intervention group (p < 0.001). There were no statistically significant differences between the two groups with respect to clinical and laboratory treatment outcomes. The mean total treatment cost was significantly lower in the intervention group (5.98 ± 6.10 vs 9.71 ± 7.55 million VND, p < 0.001). Logistic regression analysis showed that the clinical pharmacist-led interventions were associated with a higher rate of IV-to-PO switching, whereas increasing age was negatively associated with the likelihood of switching. Conclusion: Implementation of clinical pharmacist-led IV-to-PO antibiotic switch improved the rate of appropriate early conversion and demonstrated superior cost-effectiveness without compromising clinical outcomes. This strategy could serve as an effective antimicrobial stewardship intervention to optimize antibiotic use in hospitalized patients.