A prominent Republican senator took aim at the federal agency that oversees Medicare and Medicaid programs, demanding officials address a former employee’s allegations that it gave special treatment to information requests from hedge funds and consultants “who seek to profit from government information.”

Sen. Chuck Grassley sent a letter on Monday to the Centers for Medicare and Medicaid Services asking for details on agency officials’ dealings with outsiders, and how they safeguard against the passing of insider information.

The former employee has alleged that “high level CMS employees attended lengthy information gathering briefings at the request of hedge funds and political intelligence brokers with no discernible benefit to CMS or the federal government,” Mr. Grassley wrote in his letter to Marilyn Tavenner, the agency’s acting administrator.

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