The two drugmakers - among the world's largest vaccine makers - as well as U.S.-based Emergent Biosolutions Inc will work with U.S. universities and smaller biotechnology companies at one of three centers to develop and manufacture the medicines.

The U.S. Department of Health and Human Services announced the partnership to ensure enough critical medicines - such as protection against pandemics like influenza or biological attacks like anthrax - are manufactured within U.S. borders.

"We anticipate that together, the centers will be able to produce a quarter of a nation's pandemic influenza vaccine within four months of the onset of a pandemic," said Dr. Nicole Lurie, the assistant secretary for preparedness and response at HHS.

In 2009, only one H1N1 vaccine maker had facilities that were located only in the United States, she said.

The grants also aim to help smaller biotech companies to turn their ideas into successful products.

The bulk of the government's initial $400 million grant will go towards maintaining or expanding manufacturing facilities to make sure they can make several different medicines, and easily switch from one medicine to another in case of an emergency.

GlaxoSmithKline will be part of a $176 million five-year grant in Texas, Novartis will head a $60 million four-year grant in North Carolina, and Emergent will work on a $163 million eight-year grant in Maryland.

The grants can be renewed for up to 25 years and will be overseen by the Biomedical Advanced Research and Development Authority within HHS.

(Reporting by Anna Yukhananov; editing by Sofina Mirza-Reid)

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