Managers of the Tricare military health benefits program haveawarded the administration contract for the program's East regionto a unit of Humana, and the contract for theprogram's West region to a unit of Centene.

Tricare is a federal program that provides health and dentalbenefits for military personnel, reservists, the dependents ofmilitary personnel, and military retirees.

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Each regional contract starts with a nine-month coverage baseperiod and includes up to five one-year contract extensionoptions.

The East region contract that Humana won has a potential valueof $40.5 billion, according to the Defense Health Agency, an arm of the U.S.Department of Defense.

The West Region contract could be worth $17.7 billion.

Centene, the winner of the West region contract, would handlethe contract through its Health Net Federal Services unit. Centeneacquired Health Net, the federal services unit's parent, inMarch.

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The two regional programs could provide health coverage for atotal of about 9.2 million people, according to a program bid solicitation package.

The base periods for the two contracts are supposed to start onthe date of award and last until the start of health care delivery.The first of the five option periods is supposed to start April 1,2017.

Tricare replaced the old Champus military civilian healthbenefits program in 1997. Tricare had 12 regions in 1997. It nowhas three regions. The current bidding process is on track toreduce the number of regions to two.

Insurers that fail to win Tricare contracts during the firstround of bidding can, and often do, file appeals, and the appealssometimes succeed. Tricare managers say they received fourbids for the East region and three for the West region.