Science Applications International Corp. will perform initial upgrades on 10 prototype Marine Corps Assault Amphibious Vehicles, known as AAVs, with the work to be done primarily in Charleston, the company said Thursday.

The Marine Corps’ Program Executive Officer for Land Systems exercised options under SAIC’s prime contract for the work, according to the company. The options add $53 million, bringing the contract’s value to $69 million. If the Marines exercise all of the options, the contract would be worth about $194 million over five years, SAIC said.

Later options, if exercised, would lead to developmental testing and low-rate initial production of 52 vehicles for operational testing and for Marine units, the company said.

SAIC said it would upgrade the vehicles to improve protection while restoring the land and water mobility the vehicle needs. The work includes new armor, an engine rebuild for more horsepower and torque, a replacement for the aging transmission, suspension upgrades, new water jets, blast-resistant seats and upgraded controls, instruments and driver interface systems.

The program started as a competition. In June 2014, SAIC reported that the Marines had awarded it one of two prime contracts for the engineering phase, with an initial value of $16 million, and that options for prototypes and production would go to only one of the two companies. SAIC said Thursday’s award is a single-award, firm-fixed-price contract.

“This significant win demonstrates SAIC’s ingenuity to meet the demands of our customers and to serve the mission interests of the USMC,” said Tom Watson, senior vice president and general manager of SAIC’s Navy and Marine Corps Customer Group.

SAIC, based in McLean, Virginia, has about 13,000 employees and annual revenue of about $4 billion, according to the company.

SAIC also holds a major lease in the Charleston area. On Feb. 1, SAIC began a lease of a 302,400-square-foot building in Hanahan that it had previously subleased, according to a filing by the building’s owner, Monmouth Real Estate Investment Corp. The lease runs through April 2019 at an initial annual rent of about $1.4 million.