ES-285 x HCl is a novel marine-derived anticancer agent isolated from the clam Spisula polynyma. The compound is pharmaceutically formulated as a lyophilised product containing 25 or 50 mg ES-285 x HCl and 500 or 1000 mg 2-hydroxypropyl-beta-cyclodextrin per dosage unit and requires reconstitution with sterile water for injection before intravenous administration. The aim of this study was to determine the stability and compatibility of ES-285 x HCl in infusion devices. ES-285 x HCl was shown to be stable at concentrations of 10-1400 microg/ml after dilution in 5% dextrose in water and compatible with PE infusion containers and PE and silicone tubing. No sorption on- or into the administration set was observed at concentrations equal to or above 20 microg/ml. In conclusion, ES-285 x HCl infusion solutions can be administered without stability or sorption problems using a PE infusion container and PE or silicone tubing in concentrations equal or above 20 microg/ml in 3-hour or 24-hour infusion administration schedules.