Two companies have joined UnitedHealthcare in protesting military contract awards worth up to $58 billion to manage the Tricare health program, including one of the winning bidders, Government Accountability Office officials said Monday.

Health Net Federal Services, which now manages the Tricare North Region and was awarded the contract to manage Tricare's West region, filed a protest late Friday over the Defense Department's decision to give the East region contract to Humana Government Business.

The West region contract has a maximum value of $18 billion over six years, while the six-year East region contract is potentially worth $41 billion.

Joining the protest over the the Tricare East contract decision is WellPoint Military Care, a division of Anthem Blue Cross and Blue Shield created to vie for the lucrative contract. WellPoint filed its protest on Aug. 2.

The Defense Department announced the winners of the next generation of Tricare contracts, called T-2017, on July 21. The Tricare health program oversees private health services for nearly 9.4 million military family members, retirees and active duty personnel.

UnitedHealth Military & Veterans, which manages the Tricare West contract, was the first to file protests over the awards. It was not selected to manage either of the new consolidated regions and on Aug. 2 submitted its challenges to both the East and West region contract decisions.

All of the companies received briefings regarding the government's decisions the week after the award announcement. Under the government contracting process, the Defense Health Agency now has 30 days to respond to the protests, and the GAO then has until mid-November to accept or deny the protests.

The last round of Tricare contract awards stretched nearly four years, with companies protesting the initial decisions and filing lawsuits over later decisions. In the end, none of the companies originally chosen to manage the three regions ended up overseeing those for which they originally were selected.

Defense Health Agency officials told reporters July 25 that the contract disputes will not affect beneficiaries, adding that the contracts will not transfer until the Pentagon has made sure the new companies are ready.

DHA director Navy Vice Adm. Raquel Bono said the agency has confidence its selection process was thorough and fair.

"We have a very good way of describing and defending why our selections were made," she said.

According to DHA, the companies were measured for their ability to perform, provide integrated case management and maintain interoperability with military hospitals and clinics.

The new contracts also require an upgraded electronic referral process to reduce wait times for beneficiaries for specialty care.

Patricia Kime covers military health care and medicine for Military Times. She can be reached at pkime@militarytimes.com.