A microphysiological system with a synthetic hemoglobin, Blood Substitute, for mechanistic assessment of drug-induced liver injury

Drug induced liver injury (DILI) is a concern for patients, clinicians, the FDA, and the pharmaceutical industry as the leading cause of clinical drug attrition and post-marketing drug withdrawals. According to the FDA, DILI has been the most frequent cause of safety-related drug withdrawals for the past 50 years. As a potential solution to the problem, the IQ-MPS Affiliate to the International Consortium for Innovation and Quality in Pharmaceutical Development highlighted the need to qualify human liver microphysiological systems (MPS) for DILI context of use (CoU) with a set of pragmatic engineering and quality requirements for the MPS implementation into standard operating procedures. During an ongoing NCATS SBIR, Lena Biosciences (LB) developed and commercialized an SLAS-standardized, Perfused Organ Panel MPS that meets these prerequisites. The ultimate goal of this SBIR is to qualify the MPS with a revolutionary synthetic hemoglobin, Blood Substitute, for DILI CoU using the guidance of the FDA CDER and the IQ-MPS Affiliate. Our recent publication (Front. Mol. Biosci. 2020) shows that the MPS restores cellular oxidative metabolism in diverse, perfused, 3D liver models, significantly increasing cell respiration by mitochondrial electron transport chain, CYP450 oxidation required for metabolism of drugs, and OXPHOS ATP production required for holistic cell function, and all cell processes from active transport of molecules across the cell membrane to organelle function. An OXPHOS-competent model of cellular redox homeostasis will provide in vivo-like cell sensitivity to drugs and their reactive metabolites and free radicals, and drug-induced oxidative and nitrosative stress that leads to the loss of cellular antioxidant defense for comprehensive characterization of DILI threats, positioning the MPS to adequately meet biological qualification prerequisites for DILI CoU. While numerous factors contributing to DILI have been reported, to date there is no consensus on the rank of these factors for in vitro testing using primary human cells, and on the types of in vitro assays that are the most relevant for DILI prevention. Therefore, in this SBIR we will focus on testing those compounds that the drug industry found the most difficult to de-risk, examine the role of oxidative cell stress in the sequence of cellular events that lead to DILI, provide mechanism-informative insight into the DILI sequelae using a battery of assays to isolate the trigger(s) and identify causalities, and resolve temporal and log-fold change in biomarkers, including the FDA-designated biomarkers for clinical exploration, relative to vehicle controls and in relation with the coinciding rise of ALT and ALP, clinical DILI biomarkers, in order to isolate those with the highest log-fold change and specificity at low or moderate ALT. To successfully carry out the studies and ensure the project’s success, we have assembled a team of experts in advanced, OXPHOS-competent cell cultures (LB), and predictive screening of drug-induced livery injury (Dr. Salman Khetani, UIC).