# Research on the Clinical Practical Use of Pivoxil-Conjugated Antibodies and the Risk of Carnitine Deficiency Using Real-World Data

## TL;DR

This study examines the use of pivoxil-conjugated antibodies in children and finds no significant increase in carnitine deficiency risk compared to amoxicillin.

## Contribution

The study provides real-world evidence on the safety of pivoxil-conjugated antibodies in terms of carnitine deficiency risk.

## Key findings

- PV prescriptions decreased yearly from 2016 to 2021, with over 80% dispensed in clinics.
- Propensity score matching found no significant difference in carnitine deficiency risk between PV and amoxicillin groups.
- The risk of carnitine deficiency with PV is not significantly higher than with other antibiotics.

## Abstract

In Japan, pivoxil-conjugated antibodies (PVs) are commonly used to treat infections. However, carnitine deficiency is a known adverse drug reaction associated with PV treatment. This study aimed to research the practical use of PV and assess the risk of carnitine deficiency in patients receiving PV compared to their amoxicillin (AM)-treated counterparts. The Pediatric Medical Information Collection System (P-MICS) served as the data source for this study. The study cohort comprised patients aged 0–15 years prescribed PV between April 2016 and March 2021. Data on the actual PV prescriptions were extracted for each patient. To evaluate the risk of carnitine deficiency, adverse events (AEs) were defined as carnitine deficiency and its associated symptoms. Propensity score matching was employed to compare the AE incidence between the PV and AM groups. The number of cases of PV prescriptions decreased year-on-year between 2016 and 2021, and >80% of prescriptions were dispensed in the clinic. The propensity score matching analysis demonstrated no statistically significant difference in the incidence of carnitine deficiency and its associated symptoms between the PV and AM groups. Our findings suggest that the risk of carnitine deficiency in children treated with PV is not significantly higher than that associated with other antibiotics.