The use of vitamin-drug formulations to (a) enable oral absorption of pharmaceutically active ingredients which are not normally absorbed in the GI tract and (b) enhance delivery of drugs to diseases such as cancer and rheumatoid arthritis.

Vitamin-mediated drug delivery.

Oral delivery is the preferred method of administration of drugs where either long-term or daily use is required. However, many therapeutics, including peptide and protein drugs, are poorly absorbed or unstable when given orally. With more and more peptide and protein based biopharmaceuticals entering the market, there is an increasing need to develop an effective oral delivery system for them, as well as for long-standing injected drugs such as insulin.

Our oral delivery technology utilizes the body's natural vitamin B12 (VB12) transport system in the gut. Our scientists discovered that VB12 will still be transported by this process even when drugs, macromolecules, or nanoparticles are coupled to VB12. Thus VB12 serves as a carrier to transfer these materials from the intestinal lumen to the bloodstream. For drugs and macromolecules which are stable in the gastro- instestinal tract, the drug or macromolecule can be coupled directly or via a linker to VB12.

A further option, especially for drugs and macromolecules which are unstable in the intestine, is to formulate the drug in a nanoparticle which is then coated with VB12. Once in the bloodstream, the active is released by diffusion and/or erosion of the nanoparticle. Utilization of nanoparticles also serves to "amplify" delivery by transporting many molecules at one time due to the relatively large volume of a nanoparticle.

A further application of the use of vitamin-drug conjugates utilizes the fact that in many diseases where there is rapid growth and/or cell division, the demand for certain vitamins increases. By coupling the drug to an appropriate vitamin, the vitamin serves as a carrier to increase the amount of drug at the disease site relative to its normal distribution.

The drawbacks of current chemotherapeutic treatments, which include tumor resistance, cancer relapse and toxicity from severe damage to healthy tissues, has fueled a scientific quest for novel treatments that are specifically targeted to malignant cells, thus reducing damage to collateral tissues. Access' vitamin-mediated drug delivery provides for 'amplification' of the targeting effect by attaching the vitamin and drug to a polymer, or encapsulating the drug in a nanoparticle which is coated with the vitamin.

Preclinical

Several patents issued and several applications submitted.

Co-development.