By Michael S. Rosenwald
Washington Post Staff Writer
Friday, April 4, 2008

Iomai, a small Gaithersburg drug company, said yesterday that pharmaceutical firm Merck would test a patch Iomai is developing that is designed to stimulate a stronger immune system response to vaccines.

The testing will be conducted on animals, a very early step in the long march toward developing a commercial product. The companies declined to say which vaccine Merck would use with Iomai's patch.

"Merck has a portfolio of vaccines, and some work not as well as they want them to," Iomai chief executive Stanley C. Erck said.

That's where Iomai comes in. The company's business strategy is to use stimulants in patches to make vaccines more effective and also to potentially lessen the amount of substance needed to produce immunity to diseases such as pandemic flu.

The deal with Merck, though preliminary, is a boost to Iomai's efforts to win validation for its technology.

Iomai is developing the patches on several fronts. One front looks at the patch in conjunction with a vaccine for traveler's diarrhea, for which the company has reported positive results from mid-stage human testing. For that, the vaccine and the stimulants are combined into a single patch, which is worn for hours.

Iomai has also reported positive early-stage studies using the patch with the pandemic flu vaccine as part of a $128 million contract with the Department of Health and Human Services. In that instance, the patch is worn in combination with a separate inoculation.

The company has been less successful in using the patch alone to prevent seasonal flu. It failed early-stage testing last year, though Iomai executives say they have isolated the problem and are working on a fix.

As part of the Merck deal, the drug giant is paying for the testing and has the first option to negotiate an exclusive license.

Shares of Iomai closed yesterday at $1.76, up 20 cents.