SELF NEUTRALIZING OLIGONUCLEOTIDES WITH ENHANCED CELLULAR UPTAKE

DESCRIPTION provided by applicant There is enormous potential for oligonucleotides ON as therapeutics but the challenge remains how to effectively deliver ON into cells Cell membranes resist the cellular uptake of currently used charged ON The application of various delivery systems has only partially solved the problem and is often associated with therapeutically unacceptable side effects Low level cellular uptake has been the main reason of the failure of large number of ON targeting cancer genetic and microorganism mediated diseases Specific aims for the Phase I were development and validation of two new types of phosphoramidite monomers their use for the synthesis of ZATA ON with enhanced cellular uptake and demonstration that ZATA ON possess an optimal combination of properties necessary for high in vivo therapeutic activity such as enhanced cell penetration high efficacy toward silencing of target genes low or lack of toxicity at therapeutic concentrations maintenance of natural hybridization properties stability in plasma biological fluids solubility n aqueous media and robust method of synthesis allowing scale up As demonstrated in the Progress Report section we fully completed all Phase I specific tasks and for the first time have developed ON with new composition of matter that practically satisfies the complex criteria outlined herein Particularly novelties implemented in ZATA ON enabled a times higher cellular uptake vs similar oligonucleotides without ZATA modifications b over inhibition of cancer cell growth in culture with single treatment at a concentration as low as M c high stability in serum and d lack of cytotoxicity at a concentration as high as M Our achievements can briefly be defined as a novel class of ON synthesized via standard phosphoramidite chemistry which permits facile attachment of Charge Neutralizing Groups CNG bearing positive charges at their termini capable of reaching the adjacent negative charges and neutralizing them Charge neutralization in combination with added partial hydrophobicity across the backbone of ON dramatically enhance cellular uptake and gene silencing efficacy Our major goal for the Phase II of this technology development is further validation of ZATA ON by demonstrating their high therapeutic efficacy in vitro and in vivo mouse models The main tasks for Phase II study are Optimization and scale up of the synthesis of all four modified RNA phosphoramidites enabling the incorporation of optimal CNG i e Bis dimethylamino ethoxy propan ol into the backbones of our ON Synthesis and screening of over two dozen ON targeting oncogenic miR b and miR in human glioblastoma and breast cancer cell lines Scale up of the best ON drug candidate s and testing in vivo in mouse model using human glioblastoma xenografts as a target Novelties developed in the Phase I study are subject to ZATAandapos s new PCT patent application PUBLIC HEALTH RELEVANCE Development of a novel class of oligonucleotides ON is reported ZATA ON exhibited four times higher cellular penetration compared to currently used ON analogs and close to quantitative inhibition of cancer cell growth in culture Proof of principle in in vivo experiments is intended