Biotech company Emergent BioSolutions Inc. announced Friday that it has signed a two-year, $100 million contract with a government agency to produce an anthrax vaccine. according to a filing with the Securities and Exchange Commission.

The Biomedical Advanced Research and Development Authority, a division within the Office of the Assistant Secretary of Preparedness and Response, is the government agency that has asked for delivery of BioThrax to be added to the strategic national stockpile .

This contract is separate from the Gaithersburg, Maryland-based company’s $911 million BioThrax procurement contract with the Centers for Disease Control and Prevention.

“Emergent is pleased to support BARDA in its efforts to enhance the nation’s preparedness against the threat of anthrax,” said Adam Havey, executive vice president and president biodefense division at Emergent BioSolutions, in a statement. “Emergent is committed to developing and manufacturing preparedness solutions that address our customers’ needs to protect against a broad spectrum of public health threats.”

The company also signed a modification to its Sept. 30, 2016, contract with the authority for NuThrax, the company’s next generation anthrax vaccine. The modification increases the number of doses of NuThrax to be delivered from 2 million to 3 million.

Emergent Biosolutions shares were trading at $30.48, down 41 cents, or 1.3 percent, in Friday morning trading.