PRESS RELEASE: Merck Announces FDA Acceptance of NDA for CORDAPTIVE

Merck Announces FDA Acceptance of NDA for CORDAPTIVE (ER niacin/laropiprant), Formerly Known as MK-0524A, an Investigational Lipid-Modifier

WHITEHOUSE STATION, N.J. -- Merck & Co., Inc. announced today that the New Drug Application (NDA) for CORDAPTIVE(TM) (ER niacin/laropiprant), formerly known as MK-0524A, has been accepted for standard review by the U.S. Food and Drug Administration (FDA). Merck anticipates FDA action in the second quarter of 2008. The Company is also moving forward as planned with filings in countries outside the United States.

CORDAPTIVE is an investigational compound containing Merck's own extended-release niacin and laropiprant, a novel flushing pathway inhibitor designed to reduce flushing often associated with niacin treatment. Data included in the application support the proposed use of CORDAPTIVE, either alone or with a statin, as adjunctive therapy to diet for the treatment of elevated LDL cholesterol (LDL-C or "bad" cholesterol), low HDL cholesterol (HDL-C or "good" cholesterol) and elevated triglycerides levels. All are conditions associated with increased risk of heart disease.

Niacin is widely recognized as an effective lipid-modifying therapy; however, treatment has been limited as a result of the flushing side effect.

The Company expects to present Phase III data for CORDAPTIVE at both the September 2007 Scientific Meeting of the European Society of Cardiology and the November 2007 Scientific Meeting of the American Heart Association.

About cholesterol

Cholesterol is one of several fatty substances (lipids) found in the bloodstream. A person's total cholesterol is made up mainly of LDL-C and HDL-C. LDL-C is often called "bad" cholesterol because it can build up in the walls of the arteries and form plaque. Over time, the plaque can clog the arteries, resulting in a heart attack or stroke. HDL-C is often called "good" cholesterol because it helps keep LDL-C from building up in the arteries and because it protects against heart disease. Triglycerides are another form of fat in the blood, and may raise a person's risk of heart disease.

It is projected that nearly 100 million people in the United States have at least one abnormal lipid parameter. Approximately 55 million Americans have high LDL-C, 55 million have low HDL-C, and 28 million have high triglycerides.

About Merck

Merck & Co., Inc. is a global research-driven pharmaceutical company dedicated to putting patients first. Established in 1891, Merck currently discovers, develops, manufactures and markets vaccines and medicines to address unmet medical needs. The Company devotes extensive efforts to increase access to medicines through far-reaching programs that not only donate Merck medicines but help deliver them to the people who need them. Merck also publishes unbiased health information as a not-for-profit service. For more information, visit www.merck.com.

Forward looking statement

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.