Novavax, a Gaithersburg vaccine-development company working to stop the spread of the Ebola virus and other infectious diseases, plans to add 850 new jobs in Montgomery County, aided by $7.5 million in state and local assistance, officials announced Wednesday.

The company recently signed a lease for approximately 150,000 square feet of new space for lab work and manufacturing on Clopper Road, about a mile from its current headquarters. The expansion will enable the firm to triple the size of its staff to 1,250 from from 400.

The company is receiving $5 million in loans from Maryland’s economic development fund, $2.5 million in grants from Montgomery County and a $50,000 grant from the city of Gaithersburg — funding that officials said is contingent on the company’s progress in meeting the commitment to 850 new jobs. Novavax may also qualify for state tax credits and other programs.

“The primary focus of our administration is to help foster greater economic opportunity for our citizens and create jobs,” Gov. Larry Hogan (R) said in a statement. He called the expansion “a win for hardworking Marylanders and our state as a whole.”

Novavax, which is also located in Rockville and Sweden, is developing an Ebola vaccine that is in clinical trials. It recently announced that it is in the early stages of work on a possible vaccine for the Zika virus.