Editor's Note: Onselex Pharmaceuticals Inc. is a U.S. company incorporated in Delaware. The original article identified Onselex as a Korean company. Two technical descriptions in the reproduced article have been updated to clarify that paclitaxel is chemically bound to a water-soluble polymer rather than encapsulated, and that endocytosis refers to cellular uptake.

Current chemotherapy regimens are often limited in the amount of drugs they can safely deliver to patients without becoming toxic or causing too many adverse side effects.

A Korean company is hoping to expand the efficacy of existing cancer drugs like paclitaxel by packaging them in nanoparticles programmed to deliver the medication directly into pancreatic tumor cells.

Onselex has developed what it calls an "intelligent cancer drug" able to home in on tumors and deeply penetrate tissues for extremely precise drug delivery. The company's lead candidate, ONX-1006 , uses paclitaxel chemically bound to a water-soluble polymer to form stable nanoparticles.

How it Works

The biocompatible polymer blocks paclitaxel from acting on normal cells while it makes its way to cancer cells via the enhanced permeability and retention (EPR) effect, which relies on abnormal molecular and fluid transport within a tumor. To meet urgent demands for nutrient and oxygen supplies, the blood vessels feeding tumors are highly permeable, allowing macromolecules to enter and become trapped inside the tumor tissue for a prolonged period of time. After cancer cells take up the nanoparticles through endocytosis, paclitaxel is released inside the cells, killing the cancer cells.

The hope is that this drug delivery method will maximize the effectiveness of anti-cancer medicines while minimizing collateral damage to healthy cells and reducing treatment-related side effects, allowing patients to carry out normal daily activities during cancer treatment.

Starting Clinical Trials

Tests in animals with implanted patient tumor tissues showed anticancer effects (reduced tumor size and suppressed growth) that were significantly higher than with existing chemotherapy regimens. ONX-1006 was very well tolerated in preclinical trials and was able to be administered by IV once a week for 13 weeks with no observable adverse effects.

The next step will be to test ONX-1006 in a clinical trial. The company has announced it will soon begin a phase I/II trial, administering weekly doses of ONX-1006 to stage IV pancreatic cancer patients for three to 12 months. It has already produced 15kg of ONX-1006, enough for 30,000 IV injections.