Adsorption and Clearance of the Novel Fluorescent Tracer Agent MB-102 During Continuous Renal Replacement Therapy: In Vitro Results

MB-102 is a novel fluorescent tracer agent that is exclusively removed from the body by glomerular filtration. This agent can be detected transdermally to provide a real-time measurement of glomerular filtration rate at the point-of-care and is currently in clinical studies for such. MB-102 clearance during continuous renal replacement therapy (CRRT) is unknown. Its plasma protein binding (~0%), molecular weight (~372 Da) and volume of distribution (15–20 L) suggest that it may be removed by renal replacement therapies. To determine the disposition of MB-102 during CRRT, an in vitro study assessing the transmembrane clearance (CL(TM)) and adsorptive clearance of MB-102 was conducted. A validated in vitro bovine blood continuous hemofiltration (HF) and continuous hemodialysis (HD) models were performed using two types of hemodiafilters to evaluate CL(TM) of MB-102. For HF, three different ultrafiltration rates were evaluated. For HD, four different dialysate flow rates were evaluated. Urea was used as a control. No MB-102 adsorption to the CRRT apparatus or either of hemodiafilters was observed. MB-102 is readily removed by HF and HD. Dialysate and ultrafiltrate flow rates directly influence MB-102 CLTM. Hence MB-102 CLTM should be measurable for critically ill patients receiving CRRT.