Are laboratory parameter (biomarker) values similar to the healthy volunteer reference range in all patient populations?

David A Brott,1 Michael J Goodman,1 Richard P Hermann,1 Michael Merz,2 Roser Calvo,1 Nadereh Poorkhalkali,3 Alexandre Kiazand1 1Patient Safety, Safety Science, AstraZeneca Pharmaceuticals, Gaithersburg, MD, USA; 2Patient Safety, Safety Science, AstraZeneca Pharmaceuticals, Webel, Germany; 3Patient Safety, Safety Science, AstraZeneca Pharmaceuticals, Gothenburg, Sweden Background: Liver biomarkers alanine aminotransferase (ALT) and bilirubin in patients with hepatitis are above the healthy volunteer reference range (HVRR) at baseline (prior to receiving the clinical trial medication). Discussions continue as how to best distinguish drug-induced liver injury in patients with abnormal baseline values participating in clinical trials. This study investigated if other baseline routine clinical safety biomarkers (lab parameters) are different from the HVRR. Materials and methods: Clinical trial data (TransCelerate dataset) from placebo and standard of care treated patients were compared to the HVRR using a 10% threshold above or below the HVRR to classify a lab parameter in a patient population as potentially different from the HVRR at baseline. The TransCelerate dataset, batch 4, contained data from patients with Alzheimer’s, asthma, COPD, cardiovascular disease, diabetes, hidradenitis, hypercholesterolemia, rheumatoid arthritis, schizophrenia, stroke, and ulcerative colitis. A subset of the 200 biomarkers in TransCelerate were evaluated in this pilot: glucose, platelet count, neutrophil count, ALT, aspartate aminotransferase (AST), and bilirubin. Results: Glucose was potentially higher than the HVRR in patients with diabetes, COPD, cardiovascular disease, hypercholesterolemia, and schizophrenia. At least one or more of the hematology and hepatic biomarkers were different from the HVRR in at least one patient population, except bilirubin. All the patient populations, except Alzheimer’s and asthma, had at least one biomarker that was higher than the HVRR. Summary: The routine biomarkers evaluated in this pilot study demonstrated that not all lab parameters in patient populations are similar to the HVRR. Further efforts are needed to determine which biomarkers are different from the HVRR and how to evaluate the biomarkers in patient populations for detecting drug-induced altered lab values in clinical trials. Keywords: patient populations, reference range, healthy volunteer, biomarkers