Doxorubicin dramatically enhanced with lysolipid thermally sensitive liposomes (LTSL)

Using its LTSL technology, Celsion has encapsulated doxorubicin, a proven and frequently used cancer drug, to create ThermoDox®. The heat-sensitive liposome rapidly changes structure when heated to a specific temperature, creating openings in the liposome which release doxorubicin directly into the targeted tumor.

ThermoDox®, delivered by IV infusion, is designed to be used in combination with hyperthermic (heat-based) treatments, such as radiofrequency thermal ablation (RFA), microwave hyperthermia and high intensity focused ultrasound (HIFU). The goal of the ThermoDox® approach is to expand the effective treatment zone of these technologies to capture micro-metastases which are most commonly responsible for post-treatment disease recurrence. For example, in primary liver cancer patients, there is a very high one-year recurrence rate to the immediate area of the original ablated region; addressing this expanded area as part of the treatment regimen may potentially reduce recurrence rates and improve patient outcomes.

ThermoDox® leverages two mechanisms of tumor biology to deliver higher concentrations of drug directly to the targeted tumor site. First, tumors have leaky vasculature, which is permeable to liposomes and enables their accumulation within tumors. Second, when heated, blood vessels in tumors become even more permeable, further increasing the accumulation of liposomes in tumors before releasing the drug payload. The potential of this approach has been demonstrated in vivo; in animal models, ThermoDox® has been shown to deliver 25 times more doxorubicin than IV doxorubicin into tumors, and five times more doxorubicin than standard liposomal formulations of the drug.

Celsion is currently conducting a pivotal Phase III trial of ThermoDox® in hepatocellular carcinoma (HCC or primary liver cancer), known as the HEAT Study. We are also evaluating its potential in recurrent chest wall breast cancer, colorectal liver metastases and painful bone metastases. ThermoDox® also holds promise in additional solid tumor indications for which doxorubicin is indicated.