New Method Combines MRI, HIFU, Temperature-Sensitive Liposomes for Chemo Delivery Directly to Tumor

Scientists from Eindhoven University of Technology (TU/e) and Philips Research successfully tested a method of delivering doxorubicin (Adriamycin) chemotherapy agent encapsulated within temperature-sensitive liposomes (TSLs) to tumor sites. Magnetic resonance imaging was used to adjust a high intensity focused ultrasound (HIFU) machine to heat the target area and activate the release of doxorubicin from the liposomes.

From a statement by TU/e:

In pre-clinical studies using their local drug delivery proof-of-concept system designed for the treatment of certain types of tumors, Philips and TU/e achieved an increased chemotherapy drug dose at the tumor site. Some tumors contain sections poorly supplied with blood, which means that chemotherapy drugs are then not taken up evenly in the tumor. As a result, some regions receive sub-optimal doses and are therefore not effectively treated with chemotherapy. Methods for visualizing and measuring drug uptake in the tumor at time of delivery were demonstrated in the pre-clinical investigations. Such information may give an indication directly after the treatment if drug uptake was sufficient. Based on this additional information, tumors that did not receive a sufficient drug dose due to their morphology may be candidates to receive an alternative therapy.
Philips and TU/e have been working together in this exploratory research, which is also part of the EU-funded (Framework 7) European Research project ‘Sonodrugs’, for two years. The work was performed in a designated joint infrastructure in Eindhoven. Grüll and his team used a combination of MRI and ultrasound technologies together with tiny temperature sensitive drug carrying particles (called liposomes) for local chemotherapy drug delivery. The liposomes, injected into the bloodstream, transport the drug around the body and to the tumor. The latter is mildly heated using a focused ultrasound beam causing the temperature-sensitive liposomes in the tumor to release their drug payload. Simultaneous MR imaging is used to locate the tumor, measure local tissue temperature and guide the ultrasound heating. In order to monitor the amount of drug released, the liposomes also contain a clinically used MRI contrast agent which is co-released on heating. The release of the contrast agent can be monitored with MRI, allowing correlated measurements and visualizations of drug uptake in the tumor and surrounding tissue.