A method of antitumor therapy is described in which administration of a chemotherapeutic drug, encapsulated in liposomes, is supplemented by administration of an immunostimulating cytokine. The cytokine is preferably also encapsulated in liposomes. In tumor models for lung and colon carcinomas, this method produced a significantly greater therapeutic effect, as evidenced by survival rate and tumor size, than a combination of the effects produced by the free or liposome-encapsulated components administered individually. keywords: liposomes, immunotherapy

 Unique approach using Stealth liposomes offers enhanced treatment efficacy with reduced side effects

Highlights

• Apoptosis through highly controlled delivery of liposome encapsulated drugs to tumor
• Enhancement of Doxil activity with IL-2 or liposomal IL-2 for cancer therapy with direct and immediate clinical applications
• Special lipid is included in these liposomes to protect and stabilize them in the blood so they are not scavenged by white blood cells
• Half life  in the bloodstream extended 10-30 times longer than regular liposomes
• Dramatically improves patients quality of life by decreasing toxicity and side effects such as vomiting, hair loss and heart toxicity; no treatments were ceased due to side effects
• Superior encapsulation efficiency and pharmacokinetics
• Biodistribution pattern can be modified and controlled by using liposomes of various lipid composition and size, allowing the cytokine dose reduction, extended intervals between administrations, and improved therapeutic index

Our Innovation

• Provides unique delivery systems for the treatment of several cancers based on doxorubicin delivery via liposomes
• Developed techniques to to make drug-loaded nano-liposomes with high and stable drug loading that selectively reach the tumor site
• Enhances extravasation, selective, slow absorption into tumor tissue
• Sterically stabilized liposomes (SSLs) functions as Stealth liposomes: Contains a lipopolymer coating providing a “fuzzy” surface to which water molecules in the blood can cling to “camouflage” the liposomes so that they evade the immune system
• design of an allogeneic human melanoma vaccine consisting of cell membranes from several melanoma tumor cell lines expressing both MHC class I and II antigens and a 'mosaic' of various known MAAs 27-34, combined in liposomal carrier to stimulate T-cell anti-melanoma responses
• Proof of concept established in mouse, dog, and human trials

The Opportunity

• In human trials related to melanoma, nine of the 24 patients (37.5%) showed an objective response to therapy, including 3 complete (12 .5%) and 6 partial responses (25%)
• Addresses need for “patient friendly,” less toxic treatments to enhance compliance with protocols

Development Milestones

• Further research on drug carrier technologies, including SSL formulations , to develop  pharmaceutical dosage forms of cytokines for clinical application
• A large randomized clinical trial to compare the therapeutic efficacy of allogeneic melanoma vaccine with liposomal regional low-dose IL·2 vs. liposomal low-dose IL-2 only

project-id 12-2006-514

Patents pending