ACCESS PHARMACEUTICALS, INC. (OTC Bulletin Board: ACCP) announced today that it initiated an internal pre-licensing program to confirm the utility of its proprietary Cobalamin (vitamin B12) platform technology for targeted delivery of siRNA therapies. The program is considered important because, despite the widely publicized potential of RNA therapy, researchers up to now have been stymied in their efforts to design a pharmaceutical product that efficiently transports siRNA therapeutics into the cells they are designed to inhibit or kill.
Access has multiple programs ongoing around use of its Cobalamin technology to facilitate oral absorption of pharmaceuticals, including previously announced collaborations with potential pharma and biotech partners. To date, its successful Cobalamin product development program has focused on the oral delivery of insulin and human growth hormone, two peptides that currently can only be given by injection. Because these two molecules share some of the same physical characteristics as RNA's active components, Access believes its Cobalamin technology could effectively deliver RNA therapy in an oral tablet instead of by injection.
But a more compelling feature of the Cobalamin technology may be its ability to overcome the cellular transport obstacles that have held back fuller development of RNA therapy. The large size and high negative charge of RNA molecules prevents their absorption by target cells. Using the 'Trojan Horse' principle, the Cobalamin nanoparticle technology can encapsulate small fragments of RNA (siRNA) and utilize the Colalamin's vitamin B12 uptake mechanism to transport them into target cells, allowing release of the active drug to initiate the therapeutic effect. Cobalamin's vitamin B12 uptake mechanism offers the potential for targeted delivery of siRNA because most human cells have a requirement for vitamin B12. This is served by cell surface receptors, which facilitate absorption of this vitamin. In many diseases, the demand for vitamin B12 is increased, with a corresponding upregulation of the receptor.