UNITED STATES
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SCHEDULE 14A

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CAREMARK RX, INC.

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EXHIBIT INDEX

Exhibit No
99.1		Express Scripts Press Release, dated February 23, 2007

Exhibit 99.1

FOR IMMEDIATE RELEASE

Investor Contacts:		Media Contacts:
Edward Stiften, Chief Financial Officer		Steve Littlejohn, Vice President, Public Affairs
David Myers, Vice President, Investor Relations		(314) 702-7556
(314) 702-7173
Steve Balet / Laurie Connell		Joele Frank / Steve Frankel
MacKenzie Partners, Inc.		Joele Frank, Wilkinson Brimmer Katcher
(212) 929-5500		(212) 355-4449

EXPRESS SCRIPTS COMMENTS ON DELAWARE COURT OF CHANCERY RULING

Court Again Enjoins Caremark Vote On Acquisition by CVS, This Time For At Least 20 Days

Recognizes Caremark Stockholders Have Appraisal Rights

St. Louis, February 23, 2007 — Express Scripts, Inc. (Nasdaq: ESRX) today commented on the ruling by the Court of Chancery of the State of Delaware that it has again enjoined Caremark Rx, Inc. (NYSE: CMX) from holding a stockholder vote regarding the CVS acquisition, this time until at least 20 days after Caremark discloses to stockholders their right to seek appraisal and the structure of fees paid to Caremark’s bankers.

The Court ruled that the $6.00 “special dividend” to be paid to Caremark stockholders following an acquisition by CVS constitutes cash merger consideration and entitles stockholders to appraisal rights. In reaching this conclusion, the Court made several observations regarding the conduct of Caremark’s directors:

“[It] is not without some irony: it is plaintiffs, not Caremark’s directors, who have convincingly asserted an entitlement to appraisal.”

“So long as payment of the special dividend remains conditioned upon shareholder approval of the merger, Caremark shareholders should not be denied their appraisal rights simply because their directors are willing to collude with a favored bidder to “launder” a cash payment.”

“The current disclosures already suggest a certain indifference on behalf of the Caremark board and supine acceptance of any additional consideration that might descend like manna from heaven from CVS.”

“It is an unfortunate and disappointing spectacle, however, to watch a board of directors insist that it simultaneously deserves the protection of the business judgment rule because the company is not changing hands, while a massive personal windfall is bestowed because it is.”

Express Scripts commented: “We agree with the Court’s observations concerning inadequacies in the Board’s process in the sale of Caremark. Given today’s ruling, we are hopeful that the best interests of Caremark stockholders can finally be served.

“We remain ready to sit down and start discussions with the Caremark Board. The Express Scripts offer provides superior value and we look forward to commencing confirmatory due diligence as soon as possible. The advantages of an Express Scripts-Caremark combination are strategically and financially compelling. Express Scripts is offering Caremark stockholders a superior currency and greater certainty of value than CVS and has taken a number of tangible and important steps to consummate a transaction. The Company is confident that an Express Scripts-Caremark combination will deliver superior value to our respective stockholders, plan sponsors and patients.”

Caremark stockholders are reminded that their vote is important. Stockholders may be able to vote their shares by telephone or by the Internet, and are advised that if they have any questions or need any assistance in voting their shares, they should contact Express Scripts’ proxy advisor, MacKenzie Partners, Inc. Toll-Free at 800-322-2885.

Skadden, Arps, Slate, Meagher & Flom LLP, Arnold & Porter LLP, and Young Conaway Stargatt & Taylor, LLP are acting as legal counsel to Express Scripts, and Citigroup Corporate and Investment Banking and Credit Suisse are acting as financial advisors. MacKenzie Partners, Inc. is acting as proxy advisor to Express Scripts.

Safe Harbor Statement

This press release contains forward-looking statements, including, but not limited to, statements related to the Company’s plans, objectives, expectations (financial and otherwise) or intentions. Actual results may differ significantly from those projected or suggested in any forward-looking statements. Factors that may impact these forward-looking statements include but are not limited to:

	•		uncertainties associated with our acquisitions, which include integration risks and costs, uncertainties associated with client retention and repricing of client contracts, and uncertainties associated with the operations of acquired businesses
	•		costs and uncertainties of adverse results in litigation, including a number of pending class action cases that challenge certain of our business practices
	•		investigations of certain PBM practices and pharmaceutical pricing, marketing and distribution practices currently being conducted by the U.S. Attorney offices in Philadelphia and Boston, and by other regulatory agencies including the Department of Labor, and various state attorneys general
	•		changes in average wholesale prices (“AWP”), which could reduce prices and margins, including the impact of a proposed settlement in a class action case involving First DataBank, an AWP reporting service
	•		uncertainties regarding the implementation of the Medicare Part D prescription drug benefit, including the financial impact to us to the extent that we participate in the program on a risk-bearing basis, uncertainties of client or member losses to other providers under Medicare Part D, and increased regulatory risk
	•		uncertainties associated with U.S. Centers for Medicare & Medicaid’s (“CMS”) implementation of the Medicare Part B Competitive Acquisition Program (“CAP”), including the potential loss of clients/revenues to providers choosing to participate in the CAP
	•		our ability to maintain growth rates, or to control operating or capital costs
	•		continued pressure on margins resulting from client demands for lower prices, enhanced service offerings and/or higher service levels, and the possible termination of, or unfavorable modification to, contracts with key clients or providers

	•		competition in the PBM and specialty pharmacy industries, and our ability to consummate contract negotiations with prospective clients, as well as competition from new competitors offering services that may in whole or in part replace services that we now provide to our customers
	•		results in regulatory matters, the adoption of new legislation or regulations (including increased costs associated with compliance with new laws and regulations), more aggressive enforcement of existing legislation or regulations, or a change in the interpretation of existing legislation or regulations
	•		increased compliance relating to our contracts with the DoD TRICARE Management Activity and various state governments and agencies
	•		the possible loss, or adverse modification of the terms, of relationships with pharmaceutical manufacturers, or changes in pricing, discount or other practices of pharmaceutical manufacturers or interruption of the supply of any pharmaceutical products
	•		the possible loss, or adverse modification of the terms, of contracts with pharmacies in our retail pharmacy network
	•		the use and protection of the intellectual property we use in our business
	•		our leverage and debt service obligations, including the effect of certain covenants in our borrowing agreements
	•		our ability to continue to develop new products, services and delivery channels
	•		general developments in the health care industry, including the impact of increases in health care costs, changes in drug utilization and cost patterns and introductions of new drugs
	•		increase in credit risk relative to our clients due to adverse economic trends
	•		our ability to attract and retain qualified personnel
	•		other risks described from time to time in our filings with the SEC

Risks and uncertainties relating to the proposed transaction that may impact forward-looking statements include but are not limited to:

	•		Express Scripts and Caremark may not enter into any definitive agreement with respect to the proposed transaction
	•		required regulatory approvals may not be obtained in a timely manner, if at all
	•		the proposed transaction may not be consummated
	•		the anticipated benefits of the proposed transaction may not be realized
	•		the integration of Caremark’s operations with Express Scripts may be materially delayed or may be more costly or difficult than expected
	•		the proposed transaction would materially increase leverage and debt service obligations, including the effect of certain covenants in any new borrowing agreements.

We do not undertake any obligation to release publicly any revisions to such forward-looking statements to reflect events or circumstances after the date hereof or to reflect the occurrence of unanticipated events.

Important Information

Express Scripts has filed a proxy statement in connection with Caremark’s special meeting of stockholders at which the Caremark stockholders will consider the CVS Merger Agreement and matters in connection therewith. Express Scripts stockholders are strongly advised to read that proxy statement and the accompanying form of GOLD proxy card, as they contain important information. Express Scripts also intends to file a proxy statement in connection with Caremark’s annual meeting of stockholders at which the Caremark stockholders will vote on the election of directors to the board of directors of Caremark. Express Scripts stockholders are strongly advised to read this proxy statement and the

accompanying proxy card when they become available, as each will contain important information. Stockholders may obtain each proxy statement, proxy card and any amendments or supplements thereto which are or will be filed with the Securities and Exchange Commission (“SEC”) free of charge at the SEC’s website (www.sec.gov) or by directing a request to MacKenzie Partners, Inc., at 800-322-2885 or by email at expressscripts@mackenziepartners.com.

In addition, this material is not a substitute for the prospectus/offer to exchange and registration statement that Express Scripts has filed with the SEC regarding its exchange offer for all of the outstanding shares of common stock of Caremark. Investors and security holders are urged to read these documents, all other applicable documents, and any amendments or supplements thereto when they become available, because each contains or will contain important information. Such documents are or will be available free of charge at the SEC’s website (www.sec.gov) or by directing a request to MacKenzie Partners, Inc., at 800-322-2885 or by email at expressscripts@mackenziepartners.com.

Express Scripts and its directors, executive officers and other employees may be deemed to be participants in any solicitation of Express Scripts or Caremark shareholders in connection with the proposed transaction. Information about Express Scripts’ directors and executive officers is available in Express Scripts’ proxy statement, dated April 18, 2006, filed in connection with its 2006 annual meeting of stockholders. Additional information about the interests of potential participants is included in the proxy statement filed in connection with Caremark’s special meeting to approve the proposed merger with CVS and will be included in any proxy statement regarding the proposed transaction. We have also filed additional information regarding our solicitation of stockholders with respect to Caremark’s annual meeting on a Schedule 14A pursuant to Rule 14a-12 on January 9, 2007.

About Express Scripts

Express Scripts, Inc. is one of the largest PBM companies in North America, providing PBM services to over 50 million members. Express Scripts serves thousands of client groups, including managed-care organizations, insurance carriers, employers, third-party administrators, public sector, and union-sponsored benefit plans.

Express Scripts provides integrated PBM services, including network-pharmacy claims processing, home delivery services, benefit-design consultation, drug-utilization review, formulary management, disease management, and medical- and drug-data analysis services. The Company also distributes a full range of injectable and infusion biopharmaceutical products directly to patients or their physicians, and provides extensive cost-management and patient-care services.

Express Scripts is headquartered in St. Louis, Missouri. More information can be found at www.express-scripts.com, which includes expanded investor information and resources.

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