Express Scripts says ready to raise Caremark bid

A pedestrian walks past a CVS drugstore in Boston, November 1, 2006. Shareholders of CVS Corp., the No. 2 U.S. drugstore chain, on Thursday approved the company's $23.9 billion plan to buy pharmacy benefits manager Caremark Rx Inc.

NEW YORK (Reuters) - Express Scripts Inc. (ESRX.O) said on Thursday it is "firmly committed" to raising the cash part of its $27.8 billion offer for Caremark Rx Inc. CMX.N if it can find more synergies through a possible deal with the rival pharmacy benefit manager.

Express Scripts said Caremark, which has agreed to be acquired by drug-store chain CVS Corp. (CVS.N), has shut it out from conducting confirmatory due diligence.

"Caremark's closed door has prevented us from learning anything more about the company that would permit Express Scripts to increase its offer," Express said in a statement.

Earlier Thursday, CVS shareholders approved its $23.9 billion plan to buy Caremark. Caremark holders are expected to vote on Friday on the CVS deal.