P94 Reliable acquisition of plasma renin activity in the maturating renin-angiotensin-aldosterone-system by a validated small-volume assay in context of the LENA project

Abstract

BackgroundPhysiological and pathophysiological circumstances of the paediatric renin-angiotensin-aldosterone-system (RAAS) are still inadequately understood. Due to the limited paediatric data available, the LENA (Labeling of Enalapril from Neonates up to Adolescents) project aimed to comprehensively investigate the drug enalapril and its effect on humoral parameters of the RAAS. Examination of four humoral parameters, including plasma renin activity (PRA), was conducted regarding cardiac diseased paediatric population receiving enalapril, of which 60% were below 1 year of age. To fully address the agreed Paediatric Investigation Plan (EMEA-001706-PIP) of the LENA project, reliable small-volume assays for pharmacodynamics determination were mandatory to ensure the reliable data sets.Materials and methodsA commercial PRA enzyme linked immunosorbent assay (ELISA) was tailored for paediatric application and validated according to European Medicine Agency (EMA) and U.S. Food and Drug Administration (FDA) bioanalytical guidelines.1 2 In this context, accuracy, precision, total error, linearity, parallelism, matrix effects and stability were investigated.ResultsThe adopted bioanalytical PRA-assay was successfully validated. Between-run precision (CV) and accuracy (relative error) ranged from 1.6% to 19.6% and -13.0% to +11.2% respectively. Samples of five different human sources showed no substantial matrix effect and facilitated the assay’s application to heterogeneous populations. The obtained precision of parallelism of five dilution steps ranged from 7.7% to 8.3% allowing to dilute high samples within the calibration range. Stability measurements proved four freeze and thaw cycles plus short-term and long-term (37 weeks) stability. Overall, all results were complied with guideline requirements.ConclusionThe FDA/EMA-compliant PRA assay is able to accurately and precisely quantify PRA values in 50 µL plasma and is applicable for GCLP-compliant clinical studies enabling sophisticated investigations in children within the LENA project.ReferencesCommittee for Medicinal Products for Human Use (CHMP): EMEA/CHMP/EWP/192217/2009 Rev. 1 Corr. 2** Guideline on bioanalytical method validation, June, 2015U.S. Department of Health and Human Services Food and Drug Administration Center for Drug Evaluation and Research (CDER) Center for Veterinary Medicine (CVM): Bioanalytical Method Validation Guidance for Industry, May 2018Disclosure(s)Fabian K. Suessenbach, Martin Feickert, Jutta Tins and Bjoern B. Burckhardt declare that there is no conflict of interest. The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007–2013) under grant agreement n°602295 (LENA).