PharmAthene and Altimmune, a privately-held immunotherapeutics company targeting infectious diseases, announced the signing of a definitive agreement for the merger of PharmAthene and Altimmune in an all-stock transaction. Altimmune's current investors include Novartis Venture Fund, HealthCap, Truffle Capital and Redmont Capital. The combined company will be a fully-integrated and diversified immunotherapeutics company with four clinical stage and one preclinical stage programs. The proposed transaction does not affect PharmAthene's previously announced special one-time cash dividend of $2.91 per share of common stock.

"A merger with Altimmune is an ideal strategic match. It fulfills our stated goal of continuing to build value for PharmAthene shareholders after we distribute the SIGA litigation proceeds on February 3," commented John M. Gill, president and chief executive officer of PharmAthene. "By combining forces, we will diversify our portfolio into attractive commercial product opportunities and leverage our capabilities for developing next generation anthrax vaccines."

Bill Enright, president and chief executive officer of Altimmune, added, "The merger allows Altimmune to leverage PharmAthene's existing U.S. public company infrastructure, providing access to the capital markets, which is essential to the continued development of immunotherapeutics clinical programs including NasoVAX, NasoShield and HepTCell that leverage Altimmune's proprietary platform technologies."

The merger has been unanimously approved by both boards of directors and is subject to the approval of PharmAthene and Altimmune shareholders, and other customary closing conditions. Under the terms of the merger, Altimmune will become a wholly-owned subsidiary of PharmAthene in an all-stock transaction. PharmAthene will issue shares of common stock to Altimmune shareholders such that Altimmune equity holders will own 58.2% of the fully-diluted equity of the combined company. The combined company, which will operate as a public company under the name Altimmune, is expected to trade on the NYSE MKT under the ticker symbol ALT.

Bill Enright, chief executive officer of Altimmune, and Elizabeth Czerepak, chief financial officer and executive vice president of Corporate Development of Altimmune, will serve in their respective positions for the combined company. The new Board of Directors will be initially comprised of three PharmAthene directors and four Altimmune directors. The combined company's headquarters will be located in Gaithersburg, M.D. At closing the combined company is expected to have approximately $20 million in cash and cash commitments.