Standard Venipuncture vs a Capillary Blood Collection Device for the Prospective Determination of Abnormal Liver Chemistry

Abstract Background Abnormal liver function is a common manifestation of human disease and may also occur in approved and investigational medications as drug-induced liver injury (DILI). Capillary blood collection devices may allow for more frequent and convenient measurement outside of the clinic. Validation of such approaches is lacking. Methods This prospective, biospecimens collection study evaluated the Tasso+ in patients with abnormal liver tests (NCT05259618). The primary objective was to define the concordance of alanine aminotransferase (ALT) obtained via Tasso+ compared to standard venipuncture. Secondary objectives included measurement of 14 other analytes and patient surveys. At the time of venipuncture, 2 Tasso+ samples were collected: one was centrifuged and shipped, and the other was refrigerated and shipped as whole blood. Results Thirty-six patients with elevated ALT values were enrolled. In total, 100 venipuncture, 50 Tasso+ centrifuged, and 48 Tasso+ whole blood samples were obtained. Tasso+ centrifuged samples demonstrated concordance correlation coefficients (CCC) of >0.99 for ALT, alkaline phosphatase (ALP), aspartate aminotransferase (AST), and total bilirubin and CCC >0.95 for albumin, chloride, enzymatic creatinine, serum glucose, magnesium, and phosphorus. Tasso+ whole blood showed CCC of >0.99 for AST, bilirubin total, and enzymatic creatinine and CCC >0.95 for ALT, ALP, albumin, magnesium, and phosphorus. Hemolysis was comparable across the 3 sample types, but its impact was reflected in the Tasso+ potassium data. Patient feedback indicated a very favorable patient experience. Conclusions The capillary blood collection device, Tasso+, showed substantial to almost perfect concordance to standard venipuncture for measurement of abnormal liver function. Studies are ongoing to validate longitudinal sampling outside of the clinic. Clinicaltrials.gov Registration Number: NCT05259618