MabVax Therapeutics has received a contract from the National Cancer Institute under the Small Business Innovation Research Technology Program (SBIR). The award is in the amount of $1,750,000 over the next three years and will support development of a novel positron emission tomography (PET) imaging product for the diagnosis, staging, and treatment assessment of pancreatic cancer.
The product, an antibody fragment linked to a radioactive tracer, is based on the company’s discovery of a human antibody designated 5B1 that binds to a cancer antigen expressed on pancreatic cancer. MabVax discovered the 5B1 anti-sialyl-Lewisa (sLea) antibody from a patient who was vaccinated with a sLea anticancer vaccine. According to MabVax, the carbohydrate antigen sLea is expressed on pancreatic colon and stomach cancers cells at high levels where it is used as a tumor marker and presents an attractive molecular target. MabVax has generated fully human monoclonal antibodies against sLea that it says have an unusual high affinity for this carbohydrate ligand.
While the intact 5B1 antibody shows promise as a PET imaging agent in an animal model, MabVax expects the use of antibody fragments (5B1 diabodies) to provide additional benefits over intact 5B1. It also expects the 5B1 diabody to show increased clearance from negative tissues and increased tumor retention.
This latest grant is one of many MabVax has received from NCI over the years, including one of $150,000 in December of 2012 to support the manufacture and testing of the company’s neuroblastoma vaccine, and a $1.8 million Phase 2 SBIR grant back in April of 2011 to support a Phase II trial evaluating its trivalent sarcoma vaccine.