European CHMP Issues Positive Opinion for ATRIPLA(R) (Efavirenz 600 mg/ Emtricitabine 200 mg/Tenofovir Disoproxil Fumara

This press release contains "forward-looking statements" as that term is defined in the Private Securities Litigation Reform Act of 1995. These statements are based on management's current expectations and involve risks and uncertainties, which may cause results to differ materially from those set forth in the statements. The forward-looking statements may include statements regarding product development, product potential or financial performance. No forward-looking statement can be guaranteed and actual results may differ materially from those projected. Merck undertakes no obligation to publicly update any forward-looking statement, whether as a result of new information, future events, or otherwise. Forward-looking statements in this press release should be evaluated together with the many uncertainties that affect Merck's business, particularly those mentioned in the risk factors and cautionary statements in Item 1A of Merck's Form 10-K for the year ended Dec. 31, 2006, and in its periodic reports on Form 10-Q and Form 8-K, which the Company incorporates by reference.

Bristol-Myers Squibb: Media: Carmel Hogan, +33-1-58-83-65-55; Media: Sonia Choi, +1-609-252-5132; Investors: John Elicker, +1-212-546-3775; Gilead Sciences: Media: Cara Miller: +1-650-522-1616; Investors: Susan Hubbard, +1-650-522-5715; Merck & Co., Inc.: Media: Lynn Kenney: +1-908-423-4188; Investors: Graeme Bell, +1-908-423-5185