# Validated LC‐MS/MS Method for Quantifying the Antiparasitic Nitroimidazole DNDI‐0690 in Preclinical Target Site PK/PD Studies

## TL;DR

This paper describes a validated method to measure the antiparasitic drug DNDI-0690 in mouse tissues, important for understanding its effectiveness against leishmaniasis.

## Contribution

A new, accurate UHPLC-MS/MS method was developed and validated for quantifying DNDI-0690 in multiple murine biomatrices.

## Key findings

- The method showed high and reproducible recovery rates (75.9% to 94.2%) across different biomatrices.
- DNDI-0690 was stable in all tested biomatrices under various conditions.
- The method was successfully applied in a murine infection model for target site PK studies.

## Abstract

Understanding the target site pharmacokinetics (PK) of the nitroimidazole analog DNDI‐0690, a potential drug for the neglected parasitic disease leishmaniasis, is important due to the diversity of infected tissue sites and potential drug penetration variability. An ultrahigh‐performance liquid chromatography–tandem mass spectrometry (UHPLC‐MS/MS) method was developed and validated for quantifying DNDI‐0690 in murine biomatrices (plasma, liver, spleen, skin, and skin microdialysate). The method used three protein precipitation sample preparation procedures, tailored for different biomatrices, utilizing a surrogate biomatrix approach. Murine tissues were enzymatically homogenized with a Collagenase A mixture. Chromatographic detection was performed on a C18 column using gradient elution, coupled to a QTRAP6500 quadrupole MS, operating in positive ionization mode. The method demonstrated accurate and precise quantification of all murine biomatrices on the surrogate biomatrix calibration standards, with a high and reproducible total recovery ranging from 75.9% to 94.2% (CV% ≤ 2.5%). Matrix interferences were mitigated with a deuterated internal standard. Stability experiments demonstrated that DNDI‐0690 remained stable in all biomatrices under various conditions. This validated UHPLC‐MS/MS method was successfully used to quantify DNDI‐0690 in a target site murine infection model, demonstrating its suitability for future target site PK studies involving DNDI‐0690.