DDT-BMQ-000109, Qualification of biomarkers for in vitro developmental toxicity screening in a human system

项目总结/文摘

Project Summary/Abstract Stemina Biomarker Discovery, Inc. (Stemina) has developed an in vitro human pluripotent stem cell-based assay, devTOX quickPredict (devTOXqP), that uses a biomarker ratio of ornithine to cystine to predict if a compound has the potential to cause developmental toxicity over a wide range of exposures. The goal of this U01 cooperative agreement project is to qualify the devTOXqP assay’s metabolite ratio of ornithine to cystine (o/c ratio) through the Center for Drug Evaluation and Research (CDER) Biomarker Qualification Program (BQP). Stemina has an accepted Letter of Intent (LOI) to qualify the devTOXqP o/c ratio as a safety biomarker for detecting human developmental toxicity potential in vitro using human induced pluripotent stem (iPS) cells at the nonclinical stage of drug development for small molecule drugs as part of a weight-of-evidence assessment as described in the ICH S5(R3) guideline recently issued by the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH). In Aim 1, we plan to conduct a fit-for-purpose analytical method validation study for the ultra-performance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS) method used for measuring the o/c ratio to assess the precision, sensitivity, specificity, dilution linearity, reinjection reproducibility, extraction recovery, and sample carryover of the UPLC-HRMS analytical method. We also plan to measure test article concentrations and characterize test compound stability in the cell culture medium for a subset of the test compounds used in determining the relevance of the biomarker (Aim 5). A prospective qualification study will be conducted to: (1) determine the within-laboratory repeatability and reproducibility of the o/c ratio, (2) evaluate the reliability of the o/c ratio in multiple human iPS cell lines based on prediction concordance and the correlation of response to compound exposure, and (3) assess the relevance of the o/c ratio for predicting developmental toxicity potential across a broad range of pharmaceutical compounds (Aims 2, 3 and 6). Finally, we plan to establish a transfer plan with Stemina’s distribution partner to assess between-laboratory transferability and reliability of the of the devTOXqP standard operating procedures for the inter-laboratory portion of the Qualification Plan (Aim 4). Stemina’s partner will provide financial support for its part of the Qualification Plan. The studies proposed in this grant, and the in-kind support of Stemina’s distribution partner, will provide the necessary data for completing the studies described in the Qualification Plan (once approved) and submitting the Full Qualification Package. While in vitro assays such as devTOXqP will never entirely replace animals when used alone, these assays can reduce the number of compounds tested in animals. The assay may also replace the need for a second species in certain categories of compounds when used as part of a weight of evidence approach as described in the S5 (R3) guideline. Qualification of the devTOXqP assay for developmental toxicity assessment will reduce animal use and provide a human-based assessment of developmental toxicity, ultimately leading to safer drugs and fewer birth defects from chemical exposure in utero.