National Editor

VaxInnate Corp.'s immunotherapy approach netted the company $23.1 million in a Series B financing, proceeds that will fund an expansion of the scientific team and trials.

The cash gives New Haven, Conn.-based VaxInnate a little less than three years' worth of capital, said Carlo Russo, newly appointed president and CEO.

"We have enough to get an [investigational new drug application] filed and start a clinical trial," he said. "We'll probably need to raise cash when we are close to the filing."

The company's VaxIne platform is designed to exploit innate and adaptive immune responses by combining a disease-specific antigen with compounds called Pathogen-Associated Molecular Patterns to trigger activity.

Founded in 2001, VaxInnate has 12 employees with more to come and two infectious disease programs, plus one cancer program, all due to launch this year, based on findings that involve activating Toll-like receptors (TLRs) on the surface of antigen-presenting cells.

TLRs recognize structures that are common to infectious agents and, when they bind, trigger innate immune responses.

"We know our priorities, but we have others we are also considering," Russo told BioWorld Today. High on the list of indications for the infectious disease program are influenza and West Nile virus. In cancer, leukemia is the top choice.

Papers have been published in journals such as Science and Nature on TLRs, and other companies are investigating the TLR approach. Anadys Pharmaceuticals Inc., of San Diego, has ANA245, a nucleoside analogue believed to interact with TLR7, in early stage trials. Coley Pharmaceutical Group Inc., of Wellesley, Mass., has the cancer compound ProMune, which targets TLR9, in Phase II studies for melanoma and non-small-cell lung cancer. (See BioWorld Today, June 30, 2003; Aug. 26, 2003; and Nov. 18, 2003.)

Some companies have gained government funds for their TLR work. NovaScreen Biosciences Corp., of Hanover, Md., recently nailed down a biodefense contract worth about $13 million based on TLR work, and Seattle-based Corixa Corp. is investigating TLRs in respiratory-tract infections with a Bethesda, Md.-based National Institutes of Health grant of $11.6 million. (See BioWorld Today, Jan. 6, 2004, and Jan. 16, 2004.)

Russo joined VaxInnate after leaving Merck Research Laboratories, the division of Whitehouse Station, N.J.-based Merck & Co. Inc. He was executive director and head of global regulatory development, overseeing vaccines.

"What I think is interesting, and this is why I decided it was time to leave Merck, is that other people were working in [the TLR area], but they didn't really know what they were doing," he said. "There was a lot of phenomenology, people observing without understanding how the immune system works."

Russo noted there is plenty "known in terms of the TLRs and the ligands. I'm not saying we're the only one. But most of what's been done has been by serendipity. What [other researchers] found turned out to be a ligand for the TLRs, but you need to have the fusion between the ligand and antigen. And they didn't know what the ligand was for. They knew it was providing an adjuvant, but they didn't know for what."

Even knowing that an adjuvant brings toxicity issues with it - something VaxInnate avoids, he noted.

"In our case, we don't have an adjuvant," Russo said. "We're going to be able to really target the antigen, and focus immune response at the site."

The bottom line, he said, is that VaxInnate has "developed our intellectual property into the concept of bridging the innate and adaptive immune mechanisms, so we'll be able to do what others were not able to do."

VaxInnate's scientific founders are "at the forefront of the field," he said. "Lots more needs to be discovered, and that's exactly what our founders are doing." Included on the advisory roster is Ruslan Medzhitov, professor of immunobiology at the Yale University School of Medicine. It was the expertise of the likes of Medzhitov that persuaded Russo to climb aboard.

"When I was first approached, I was not particularly interested in a start-up, but I was very interested in the science," he said. The company quietly went about raising money, which turned out not to be difficult.

"There really wasn't the need to generate lots of noise in order to attract interest from venture capitalists," Russo said. Now that the company is trying to recruit research and development personnel in its push for drugs, company officials are speaking more publicly, he added.

Taking part in the VaxInnate financing were new investors HealthCare Ventures, of San Francisco; Oxford Bioscience Partners LLC, of Boston; and MedImmune Ventures Inc., of Gaithersburg, Md. Existing investor CHL Medical Partners, of Stamford, Conn., also participated.