Development and validation of a liquid chromatographic-tandem mass spectrometric assay for the quantification of cabotegravir and rilpivirine from dried blood spots

Ethel D Weld; Teresa L Parsons; Ryann Gollings; Marybeth McCauley; Beatriz Grinsztejn; Raphael J Landovitz; Mark A Marzinke

doi:10.1016/j.jpba.2023.115307

Development and validation of a liquid chromatographic-tandem mass spectrometric assay for the quantification of cabotegravir and rilpivirine from dried blood spots

J Pharm Biomed Anal. 2023 May 10:228:115307. doi: 10.1016/j.jpba.2023.115307. Epub 2023 Feb 17.

Authors

Ethel D Weld¹, Teresa L Parsons¹, Ryann Gollings¹, Marybeth McCauley², Beatriz Grinsztejn³, Raphael J Landovitz⁴, Mark A Marzinke⁵

Affiliations

¹ Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
² FHI 360, Washington DC, USA.
³ Instituto Nacional de Infectologia Evandro Chagas-Fiocruz, Rio de Janeiro, Rio de Janeiro, Brazil.
⁴ Center for Clinical AIDS Research and Education, David Geffen School of Medicine, University of California, Los Angeles, USA.
⁵ Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA. Electronic address: Mmarzin1@jhmi.edu.

PMID: 36842333
PMCID: PMC10065945 (available on 2024-05-10)
DOI: 10.1016/j.jpba.2023.115307

Abstract

Background: Dried blood spots (DBS) have been utilized as a blood plasma alternative for therapeutic drug monitoring and pharmacologic analysis. There are analytical and physiochemical considerations in bridging drug concentrations from plasma to DBS. Recently, the long-acting antiretroviral cabotegravir (CAB) has been approved for HIV prevention, and a co-packaged regimen of long-acting CAB and rilpivirine (RPV) has been approved for HIV treatment. Measurement of these drugs in blood collected as DBS may offer increased capacity and flexibility in translational applications.

Methods: Whole blood was spiked with CAB and RPV and spotted on DBS cards. Following extraction and addition of isotopically labeled internal standards, samples were subjected to liquid chromatographic-tandem mass spectrometric (LC-MS/MS) analysis. The method was validated according to regulatory recommendations, and the assay was evaluated in remnant samples from an HIV prevention trial in which paired DBS and plasma samples were collected.

Results: DBS CAB and RPV concentrations were linear from 25 to 20,000 ng/mL and 2-2500 ng/mL, respectively. Precision, accuracy, and matrix effect results were acceptable. DBS RPV demonstrated stability under all tested conditions; DBS CAB showed mean biases of - 23.5% when stored at room temperature for 36 days, and - 18.0% at 40 °C and 100% humidity for two days. DBS measurements for CAB and RPV were an average 54.0% and 14.1% lower, respectively, as compared to paired plasma samples. Derived conversion factors of 1.79 and 1.16 were applied to DBS CAB and RPV measurements, respectively, to estimate plasma concentrations. Estimated plasma CAB and RPV concentrations showed mean biases of 2.2% and 0.6%, respectively. In a CAB clinical trial, application of the conversion factor resulted in agreement between estimated plasma CAB concentrations from DBS and plasma CAB concentrations (y = 1.08x - 79.2, r = 0.932; mean bias of -3.2%; 95% CI: -48.2% to 41.9%).

Conclusions: We developed and validated a novel LC-MS/MS assay for the quantification of CAB and RPV from DBS, and identified conversion factors to estimate plasma concentrations from spotted blood.

Keywords: Cabotegravir; DBS; HIV; LC-MS; Mass spectrometry; Rilpivirine.

MeSH terms

Chromatography, Liquid / methods
Dried Blood Spot Testing / methods
HIV Infections* / drug therapy
HIV Infections* / prevention & control
Humans
Reproducibility of Results
Rilpivirine*
Tandem Mass Spectrometry / methods

Substances

Rilpivirine
cabotegravir

Abstract

MeSH terms

Substances

Grants and funding