Iomai Corp., said the the 160-subject study, part of an extensive Phase 2 program for the vaccine, measured the immune response to the vaccine patch, which is about the size and shape of an adhesive bandage.

Two groups received both doses of the vaccine from a medical professional and two other groups of volunteers administered the second vaccine patch themselves. All groups had robust responses to the vaccine, and a statistical analysis of immune parameters following vaccination showed no significant differences between treatment groups.

"These results confirm our belief that the Iomai patch can be effectively used by patients without a healthcare provider present, removing the need for a second trip to a travel clinic," Stanley C. Erck, Iomai's president, said in a statement. "Our research has shown that self-application of the second dose further enhances the market potential of this product."

No serious vaccine-related adverse events were reported, Erck said.