In vitro compatibility of admixture solutions of 5-fluorouracil and khapzory (disodium levofolinate) in a single infusion bag

First-line chemotherapy for metastatic colorectal cancer typically involves a fluoropyrimidine, like 5-fluorouracil (5-FU), along with a folate agent, levoleucovorin. However, calcium-based levoleucovorin with 5-FU necessitates sequential infusion due to incompatibility, leading to calcium carbonate precipitation and potential IV catheter occlusion. In contrast, sodium-based levoleucovorin (disodium levoleucovorin-Khapzory) exhibits higher solubility in the low pH environment of 5-FU, enabling combination within a single IV bag for simultaneous infusion. This study aims to assess the safety of combining different concentrations of disodium levoleucovorin with 5-FU to create a single IV admixture bag or single pump Y-site, without risk of precipitate formation and catheter occlusion.