Quirem Medical is a spin-off company from the University Medical Center Utrecht that specializes in the research & development, manufacturing and commercialisation of QuiremSpheres® for radioembolization.




Radioembolization is a relatively new approach for the treatment of patients with Hepatocellular Carcinoma (HCC) or liver metastases from any other primary cancer. In its current form, the treatment is available as a third line treatment for patients who underwent standard of care options like chemo or surgical options. During treatment, small radioactive microspheres are injected via a catheter into the femoral artery (groin) and moved upwards into the hepatic artery. The QuiremSpheres® have an average diameter of 30 micrometer. These radioactive microspheres log into the microvasculature around a tumor and thus deliver their radiation locally, destroying the tumor tissue. The radio nuclide used has such a short half life (26 hours) that the majority of radiation will disappear in a few days. The inactive microspheres are made of biocompatible poly-lactate acid and stay in place without any complications.



The radioactive holmium loaded particles (‘microspheres’), which have been developed by our research team, have been successfully tested for the first time in patients with liver malignancies in a clinical trial: the “HEPAR” (Holmium Embolization Particles for Arterial Radiotherapy) study. The high tumor targeting of these particles is based on the difference in blood flow between normal liver tissue and liver tumors. The liver receives 30% of its blood from an artery, the hepatic artery, and 70% of the liver’s blood supply is derived from the portal vein. Tumors in the liver receive their blood predominantly from the hepatic artery, the blood of which is oxygen and nutrient-rich. Based on this difference in blood supply, it is understandable that particles of a specific size, if administered in the hepatic artery will lodge principally in the smaller blood vessels around the tumors. This kind of therapy is also referred to as intra-arterial microbrachytherapy or radioembolization.