The patent expands the coverage for the company's TCI technology, a unique method of vaccine delivery which offers needle-free administration and the ability to deliver types of vaccines that are not viable by an intramuscular route.
TCI technology uses a patch placed on the surface of the skin to deliver vaccines and adjuvants to a group of antigen-presenting cells called Langerhans, located on the skin's outermost layer, which in turn deliver the vaccines and adjuvants to the nearby lymph nodes to produce a sustained immune response.
"This patent confirms our position as the first company to design a patch-based system that administers vaccine to the skin, a major competitive advantage," said Stanley Erck, Iomai's CEO.
"This allows us to continue our efforts to develop the first-ever vaccine for traveler's diarrhea in the United States and a needle-free influenza vaccine patch that would be simpler to administer than injectable vaccines."
Indeed, the needle-free technology can be applied to a wide range of vaccines, so Iomai has submitted to the US Department of Health and Human Services (DHHS) a proposal to receive government funding for further development of its adjuvant skin patch for pandemic influenza.
Iomai will develop a plan to produce 150m doses of its patch in a six-month period if awarded the contract.
What makes Iomai's immunostimulant patch particularly interesting for the US government is that it can be used with any avian flu vaccine to boost supplies by up to 100-fold, allowing much smaller doses of vaccine to be administered - a 'dose-sparing' approach to vaccination.
Travelers' diarrhea also has no approved vaccine at present, so Iomai's patch-based vaccine delivery promises convenience while avoiding systemic exposure to antigens or adjuvant.
Most cases of travelers' diarrhea are caused by enterotoxigenic E. coli bacteria (ETEC), and the US Centers for Disease Control and Prevention (CDC) estimates that 20 to 50 per cent of travelers to areas where the bacteria are endemic are sickened over a one- to two-week period, harbouring a potential market for a vaccine estimated at $450m (€350m) annually.
With the new patent, Iomai now holds the exclusive license to four U.S. patents and 20 foreign patents, and has filed more than a dozen non-provisional patent applications in the United States and more than 30 foreign applications.