By Allan Maurer

RALEIGH, NC—North Carolina State University professor Stefan Franzen first learned about a distinctive plant virus when he met his colleague Steven Lommel over a beer in Poland several years ago. He did not immediately realize that the meeting would lead to a new approach to nanoparticle drug delivery.

“We got a little bit lucky there,” says Franzen, who holds a PhD in biophysical and biological chemistry. “Serendipity is part of science too.”

“I had known Steve for a long time,” he says. “When I first learned of the properties of the plant virus he was studying, I didn’t get it. I was staring at it for a year without seeing why it is so advantageous. Then, it began to sink in.”

Franzen and his company, NanoVector, had been “playing with nanoparticles for a while,” in particular gold nanoparticles, for use as a targeted drug delivery mechanism. They presented difficult problems that did not show signs of being solved.

Problems with metal nanoparticles
At first Franzen thought Lommel’s plant virus might work with his gold nanoparticles, and even published some work related to the possibility. But eventually, he decided the gold nanoparticles just had too many disadvantages that “All these people who want to promote metal nanoparticles have to solve,” he says.

Lommel, a Ph.D., is a professor of plant pathology, professor of genetics, and Associate Vice-Chancellor for Research at NCSU. His primary research program is in the areas of plant virology, plant viral pathogenesis and plant genomics. He has been working with plant viruses since 1978.

The Eureka! Moment
Recalling that initial meeting in Poland six or seven years ago, Lommel says, “Stefan and I knew each other from NCSU, but didn’t know each other’s research. We shared a hotel and talked a lot. I told him we had just learned to open and close my virus and that it has a hollow cavity in it.”

That is what eventually led to the “Eureka!” moment, he says. Together, Franzen, Lommel, and Bruce Oberhardt, who had been with the company from its inception, revived the inert NanoVector.

“Since then, we have been developing it,” says Lommel of the "plant nanoparticle."

“Its natural properties give it a real advantage," he says. "It can open and close without falling apart. It has a lot of flexibility and potential.”

He points out that NanoVector is not making a drug, but rather a “drug formulation.” It will allow the company to package many current cancer drugs that are not targeted to cancer cells. Targeting drugs is the whole basic idea behind nanoparticle delivery.

Untargeted drugs that affect your healthy cells as well as cancer cells are why your hair falls out during chemotherapy.

To target, “You want to sequester the drug,” says Franzen. “You want it to go into something. You can do some clever things with polymers, but this is more elegant. It’s easier to control and has the advantage of thousands of years of evolution.”

Franzen and Lommel have had several “epiphanies” over the years since sharing beers in Poland. Recently, they realized the plant virus has a natural loading and unloading mechanism built into it. “It’s an exquisite calcium sensor,” Franzen says.

It has a lot of “up potential
Although it may take additional months of research, that finding means they can control the loading and unloading of the medicine in the virus via calcium.

NanoVector is initially targeting cancer therapies, but Franzen says that once the company overcomes regulatory issues, the system could be used to administer pain drugs or any other targeted medicines. “It has a lot of up potential,” he says.

Lommel notes that the company has received grant money and funding from private sources. “We’re doing a dance with some angel investors now,” he says.

The company brought in serial entrepreneur Albert Bender, also a PhD, who was founder and CEO of four venture-backed startups, as CEO.

“We have a division of labor here,” says Lommel. “I’m not doing the business side after spending the last 30 years studying plant viruses.”

MONDAY: Part Two: The business side of NanoVector.