Ann Arbor-based biotech firm NanoBio Corp. is entering the final phase of a three-stage approval and validation process for its topical treatment for cold sores.

NanoBio, a University of Michigan spinoff company with about two dozen employees, said today that it has launched two Phase 3 trials to test its new cold sore therapy, which is called NB-001.

Phase 3 is the final stage of clinical development testing and validation required by the U.S. Food and Drug Administration before a company can file an application to get a therapy approved for the market.

NanoBio is running two separate Phase 3 trials that will involve 1,700 patients at 72 different locations. They are expected to be finished in 2012.

Phase 3 trials are the most expensive and most difficult to successfully navigate, but if NanoBio can get its treatment onto the market, that would lead to a windfall of profits and financing the company could use to hire workers and develop its other technologies.

It would also be a win for United Kingdom-based pharmaceutical giant GlaxoSmithKline, which signed a licensing deal in 2009 for the rights to market the treatment in the U.S. and Canada. As part of the deal, GSK paid $14.5 million upfront to NanoBio and agreed to pay royalties and payments of up to $40 million if the treatment hits specific milestones.

“We are very optimistic about these trials and the path to FDA approval,” said Mary Flack, NanoBio's vice president of clinical research, in a statement. “The initiation of these trials marks a significant step towards the commercialization of a new treatment offering for cold sores, as well as potential other new offerings to come from our nanoemulsion-based platform technology.”

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