13C-methacetin

13C-methacetin (LiMAxetin) is an intravenous diagnostic small molecule developed by Humedics GmbH for the quantitative assessment of liver function capacity. It serves as a substrate for the liver-specific enzyme cytochrome P450 1A2 (CYP1A2), which metabolizes the 13C-labeled methacetin into acetaminophen and 13CO2. The resulting 13CO2 is exhaled and measured using a specialized breath analysis device (LiMAx FLIP) to calculate the LiMAx (maximum liver function capacity) value. This test is primarily utilized in patients undergoing partial liver resection or transplantation to predict the risk of post-hepatectomy liver failure and to guide surgical planning and post-operative management. It is currently being evaluated in Phase 3 clinical trials, such as the Fast-track LiveR study, to optimize recovery protocols and identify low-risk patients for early discharge.

Brand names

LiMAxetin

Other names

13-C-Methacetin13C-labeled methacetin[13C]-methacetin