2026 Eastern States Conference

Authors: Charlotte Spry, PharmD; Liz Remizowski, PharmD; Caroline Liang, PharmD, BCPS, BCPPS; Bethany Chalk, PharmD, BCPPS; Kelsey Foster, PharmD, BCPPS; Erica Prochaska, MD, MHS; Kartikeya Makker, MBBS; Alice Hsu, PharmD, BCIDP 
 
Objective: Describe the adequacy of NeoFax empiric vancomycin dosing regimens in achieving goal troughs in neonatal patients. 
 
Self-Assessment Question: Based on the results of this study, which of these statements is true regarding NeoFax empiric vancomycin dosing regimens in neonates? 
a. NeoFax empiric dosing fails to achieve therapeutic trough levels 
b. NeoFax empiric dosing achieves therapeutic trough levels 
c. NeoFax empiric dosing achieves supratherapeutic trough levels 
d. Vancomycin is not indicated in neonates 
 
Background: Vancomycin is often used in the neonatal intensive care unit (NICU) for late onset sepsis, occurring after day 7 of life. The objective of this study is to determine if empiric NeoFax vancomycin dosing achieves goal trough levels in NICU patients.  
 
Methods: We conducted a retrospective cohort study of patients admitted to two NICUs who received ≥ 24 hours of IV vancomycin with a steady state trough. Patients initiated on non-NeoFax empiric dosing or requiring extracorporeal membrane oxygenation or renal replacement therapy were excluded. Demographic data, vancomycin dosing, and steady state trough levels were collected manually from the electronic medical record. Incidence of acute kidney injury (AKI) while on vancomycin was also evaluated. Descriptive statistics were performed, including medians with interquartile range (IQR) and percentages. Chi Square and Kruskal-Wallis tests were used for comparisons, as appropriate. All analyses were performed in Stata version 18. 
 
Results: Of the 437 patients screened, 200 met inclusion criteria. Median post-menstrual age and post-natal age were 36.6 weeks (IQR 32.2-39.8 weeks) and 3.5 weeks (IQR 1.9-7 weeks), respectively. Overall, 161 (80.5%) patients were subtherapeutic with a median trough level of 7.9 mcg/mL (IQR 5.9-10.2 mcg/mL). Of patients targeting a trough of 10-14 mcg/mL, 29 (18.8%) were therapeutic and 121 (79%) were subtherapeutic, with a median trough level of 7.4 mcg/mL (IQR 5.8-9.6 mcg/mL). Of patients targeting troughs 14-17 mcg/mL, 6 (13%) were therapeutic and 40 (87%) were subtherapeutic, with a median trough of 9.7 mcg/mL (IQR 7.7-11.6 mcg/mL). AKI occurred in 13 (6.7%) patients. 
 
Conclusion: Empiric NeoFax dosing is inadequate in achieving target troughs in most NICU patients. More aggressive empiric dosing should be further investigated.