Genetically Modified Corn Could Lead to Oral Hepatitis B Vaccine

Medication would require no refrigeration and cost less than $1 per dose to manufacture.

A radical new method of producing vaccines may lead to significant new treatments that require less special handling and storage.

In a study presented at the American Society for Biochemistry and Molecular Biology annual meeting, researchers evaluated the use of genetically modified corn to produce vaccines that could lead to the creation of an oral hepatitis B vaccine requiring no refrigeration at a cost of less than $1 per dose to manufacture.

"Even though an effective injectable hepatitis B vaccine was developed more than 30 years ago, high infection rates still persist in areas of the world where people cannot afford the vaccine or do not have reliable refrigeration," John Howard, PhD, president of vaccine developer Applied Biotechnology Institute. "This research brings us a step closer to vaccines that can be distributed throughout the world without refrigeration requirements as well as administered quickly and inexpensively."

Currently, vaccines are typically manufactured by growing weakened or inactivated pathogens in eggs.

For the current study, researchers developed a non-infectious particle similar to hepatitis B virus produced via a process in which corn is genetically modified. Flour produced by corn grain can be added to sugar and water to become an edible wafer, according to the study.

Following the evaluation of several methods for processing corn, the researchers found a separation technique called supercritical fluid extraction was able to produce virus-like particles resembling those found in injected vaccines. The wafer that was produced through this method caused an immune response in mice that is up to 4 times greater than normal.

"Our work provides the first insight on how various methods of processing of plant material can affect the structure of the virus-like particles," staff scientist Shweta Shah, PhD, said in a press release. "Processing affects the structure of the virus-like particles that are formed, as well as the efficacy of the vaccine."

Proteins and enzymes from corn keep the vaccine stable during storage and shipment prior to being ingested, at which point it reaches the gut to activate an immune response. The study noted that the vaccine be stored at room temperature for years without losing efficacy.

Additionally, the materials used for each wafer cost less than 1 cent, and it can be administered without medical staff. Beyond the savings from refrigeration and medical staff, the researchers estimate the corn-based vaccine will still cost less than 10% of the cost for current injectable vaccines.