PASADENA, Calif., Sept. 10, 2003 (PRIMEZONE) -- Insert Therapeutics, Inc. Senior Scientist Jianjun Cheng, PhD, presented data this week at the American Chemical Society Meeting in New York City demonstrating the flexibility and distinct advantages of the company's proprietary Cyclosert(TM) drug delivery technology.
As Dr. Cheng discussed, Insert Therapeutics has developed linear, water-soluble, cyclodextrin-containing polymers capable of delivering a wide range of therapeutic agents directly into cells. These polymers can be neutral, positively charged, or negatively charged, and can deliver therapeutics ranging from small molecules (less than 1nm in size) to oligonucleotides (1 to 10 nm) to full plasmids (30-200 nm when condensed). With the attachment of ligands to cell surface receptors, delivery has been targeted to specific cells and tissue types.
Dr. Cheng further described the synthesis of Insert's polymer delivery system and shared preclinical data demonstrating the improvement in stability, solubility, pharmacokinetics, safety and efficacy that has been achieved using Insert's Cyclosert polymers for delivery of small molecule anticancer agents. He also presented results of recent preclinical efficacy studies in tumor-bearing mice that showed protracted tumor growth suppression following the administration of Cyclosert formulated with the small molecule anti-cancer drug camptothecin, a topoisomerase 1 inhibitor, when compared to irinotecan, the current market-leading compound with the same mechanism of action.
"Our polymers provide a systemic delivery solution for small-molecule drugs -- like camptothecin -- whose chemical structures or undesired interactions with blood components currently limit their clinical effectiveness or cause unacceptable toxicity," Dr. Cheng said. "Early pharmacokinetic data gained from our Cyclosert-camptothecin efficacy study shows the presence of Cyclosert-camptothecin in tumor cells for extremely long periods of time following the last administered dose. This protracted tumor bioavailability helps explain the extended anti-tumor activity we have witnessed."
"We believe that Cyclosert provides unparalleled flexibility to customize the basic Cyclosert polymer to address specific drug delivery challenges and therapy requirements of small molecules and nucleic acids," said Insert Therapeutics President and Chief Executive Officer, Leonard R. Borrmann, Pharm.D. "We intend to leverage this technology by building a pipeline of delivery-enhanced products and through pursuing strategic collaborations with pharmaceutical and biotechnology companies whose marketed products or proprietary development compounds could benefit from Cyclosert."
Cyclosert Technology
Insert has designed a novel class of "intelligent" materials that incorporates optimal properties for intracellular systemic delivery of a broad range of therapeutics. Insert's proprietary drug delivery technology platform, Cyclosert, uses modified cyclodextrins as building blocks. Cyclosert's linear cyclodextrin-containing polymers can be designed to be neutral, positively charged or negatively charged. This feature is unique to Cyclosert technology and provides great flexibility for formulation and delivery. Cyclosert polymers can be made biodegragable, and animal studies have confirmed that they are non-toxic and non-immunogenic at therapeutic doses , even when administered repeatedly or continuously. Cyclosert polymers have been synthesized at molecular weights ranging up to 100 kD, allowing for systemic drug delivery with the potential to slow renal clearance, enhance circulation time and improve passive accumulation of active drug at the target tissue.
Combining small-molecule drugs with Insert's cyclodextrin polymers has been shown to significantly improve the solubility, stability, in vitro toxicity, efficacy and pharmacokinetic characteristics of anticancer agents. Further, Insert's delivery system can be modified by the attachment of cell surface receptor ligands to achieve active tissue targeting and intracellular delivery of therapeutics. Unlike passive drug carriers, Cyclosert polymers respond to biological mechanisms and micro-environmental conditions enabling the controlled release of their drug payload into tumor cells or other selected tissues.
INSERT THERAPEUTICS, INC.
Insert Therapeutics, Inc., a privately held biopharmaceutical delivery company, is using its proprietary and entirely new polymeric delivery system, Cyclosert(tm), to design, develop and commercialize drug-delivery-enhanced small-molecule therapeutics and nucleic acids. Cyclosert uses cyclodextrins as building blocks to create an entirely new class of drug delivery materials - linear cyclodextrin-containing polymers that are nontoxic and nonimmunogenic at therapeutic doses. The company is pursuing this goal through its internal research and development and also through collaborations and partnerships with pharmaceutical and biotechnology companies. For more information, visit www.insertt.com.