Emergent BioSolutions of Rockville and PharmAthene of Annapolis received separate federal development contracts to develop an improved form of the anthrax vaccine.

PharmAthene of Annapolis was awarded with a multi-year contract by the National Institute of Allergy and Infectious Diseases, a part of the National Institutes of Health.

“PharmAthene is strategically building a leading franchise in anthrax countermeasures — a potentially billion dollar market,” said David Wright, CEO of PharmAthene, in a statement. The company would receive an initial $13.2 million for clinical trials and testing of the vaccine.

Emergent BioSolutions of Rockville, PharmAthene’s rival, said it has also received a federal development contract to build new anthrax vaccine. The company is the government’s single supplier of anthrax vaccine under a $448 million contract to stockpile 18.75 million doses of BioThrax.

Both Emergent and PharmAthene compete to give the Strategic National Stockpile the 25 million doses of anthrax vaccine.

An improved version of the vaccine is supposed to stimulate immunity faster, with fewer side effects. Human and animal vaccines are based on live-attenuated strains, anthrax spores, or cell-free vaccines prepared from bacterial supernatants or protein subunits, usually adsorbed onto aluminum salts, such as aluminium hydroxide.

Anthrax occurs to humans when they are exposed to infected animals, hides, or tissue from infected animals.

Anthrax Vaccine Adsorbed (AVA, trade name BioThrax), which is produced by BioPort Corporation Lansing, Michigan, is the only type of anthrax vaccine licensed by the FDA in the United States.