Iomai being acquired by vaccine maker Intercell

The $6.60-per-share deal marks a 126 percent premium from Iomai's closing price of $2.92 Monday. The buyout will involve a stock-for-stock exchange for about 41 percent of Iomai's outstanding shares held by major shareholders for about 1.7 million Intercell shares. That represents about 4 percent of Vienna-based Intercell.

The remaining Iomai shares will be bought in a cash deal.

In a statement, Iomai said the deal will bring together Intercell's Japanese Encephalitis vaccine with Iomai's needle-free travelers' Diarrhea vaccine, expected to enter late-stage studies in the first half of 2009. Combined, both vaccines represent a market opportunity of about $1 billion annually, Iomai said.

Both companies boards of directors have approved the deal, which is expected to close before the end of the third quarter.

Merrill Lynch International acted as exclusive financial adviser to Intercell and Cowen and Co. provided a financial fairness opinion to Iomai's Board of Directors.

Intercell's stock is traded on the Vienna Stock Exchange.