Humana Inc. (NYSE:HUM) announced it is cobranding a Medicare Part D prescription drug plan with Wal-Mart Stores Inc. (NYSE:WMT), Bentonville, Ark.

The agreement offers Medicare beneficiaries savings on monthly plan premiums and on prescription copayments and cost-shares, according to a joint statement by the companies.

The Humana Walmart-Preferred Rx Plan (PDP) offers one national monthly plan premium of $14.80. A typical Medicare Part D beneficiary who enrolls in the plan can save more than $450 in 2011 over an average Part D prescription, according to an estimate by Humana, Louisville, Ky.

The plan will be available to Humana Part D members using Walmart, Neighborhood Market or Sam’s Club pharmacies:

In-store copayments on generic prescriptions start as low as $2 when plan members use preferred pharmacies, according to the announcement.

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