JANUVIA(R), First in New Class of Oral Treatments Known as DPP-4 Inhibitors, Recommended for Approval for the Treatment of Type 2 Diabetes in the European Union.

Positive Opinion for Type 2 Diabetes Treatment

WHITEHOUSE STATION, N.J. -- Editor's Note: For Use by Reporters in the European Union Only.

JANUVIA(R)(1) (sitagliptin), Merck, Sharp & Dohme's treatment for patients with type 2 diabetes, today received a positive opinion from the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Evaluation Agency (EMEA) in Europe. The CHMP opinion recommends that JANUVIA be approved in the European Union for the treatment of type 2 diabetes. Following the conclusion of the CHMP review, the opinion for JANUVIA will be transmitted to the European Commission (EC). If the EC adopts the opinion, JANUVIA will be the first and only prescription medication in a new class of drugs known as dipeptidyl peptidase-4 (DPP-4) inhibitors, which enhance the body's own ability to lower blood sugar (glucose) when it is elevated. The decision will be applicable to the 27 countries that are members of the European Union, including the United Kingdom, Germany, France, Italy and Spain. JANUVIA is currently approved in eleven countries including the United States and Mexico. Marketing authorization from the European Commission is expected in early April after the adoption of the opinion.

The CHMP, comprised of regulators from all European Union countries, gave the positive opinion following a review of comprehensive data supporting the efficacy and safety and tolerability profile of JANUVIA. The submission package consisted of studies involving approximately 4,000 patients with type 2 diabetes treated with JANUVIA.

JANUVIA has been investigated in patients with type 2 diabetes to improve glycaemic control in combination with metformin when diet and exercise, plus metformin, do not provide adequate glycaemic control. JANUVIA has also been studied as add on therapy with PPAR[eth][thorn] agonists in patients with type 2 diabetes mellitus in whom use of a PPAR[eth][thorn] agonist (e.g. a thiazolidinedione) is appropriate. In addition, JANUVIA has been studied as monotherapy in many patients.

In a clinical study, JANUVIA plus metformin, compared to treatment of a sulfonylurea (SU) plus metformin, showed comparable glucose lowering efficacy. In this study patients taking JANUVIA plus metformin lost weight (-1.5 kg) compared to patients taking glipizide plus metformin who gained weight gain (+1.1 kg). Hypoglycaemia (when blood sugar becomes too low) was more common in patients treated with glipizide plus metformin (32 percent) compared to patients treated with JANUVIA plus metformin (4.9 percent). In the overall phase III clinical programme the incidence of hypoglycaemia in patients taking JANUVIA was similar to patients taking placebo (1.2 percent, JANUVIA vs. 0.9 percent, placebo). In clinical trials of up to 2 years in duration, patients have received treatment with JANUVIA alone or in combination with metformin, a sulfonylurea (with or without metformin) or a PPAR[eth][thorn] agent. In these trials, the rate of discontinuation due to adverse experiences considered drug-related was 0.8 percent with JANUVIA and 1.5 percent with other treatments. No adverse reactions considered as drug-related were reported in patients treated with JANUVIA occurring in excess (> 0.2 % and difference > 1 patient) of that in patients treated with control. Reported adverse events included nausea (common), somnolence, upper abdominal pain, diarrhoea and hypoglycaemia (uncommon).(**) JANUVIA should not be used in patients with type 1 diabetes or for the treatment of diabetic ketoacidosis, as it would not be effective in these settings.

About JANUVIA

JANUVIA (sitagliptin) is an oral, once daily, potent and highly selective DPP-4 inhibitor. DPP-4 inhibitors work by enhancing a natural body process that lowers blood sugar, the incretin system. When blood sugar is elevated, incretins work in two ways to help the body regulate high blood sugar levels: they trigger the pancreas to increase the release of insulin and signal the liver to reduce its production of glucose. DPP-4 inhibitors enhance the body's own ability to control blood sugar levels by increasing the active levels of these incretin hormones in the body, helping to decrease blood sugar levels in patients with type 2 diabetes.

Expanding Clinical Trial Program for JANUVIA

MSD's clinical development program for JANUVIA is robust and continues to expand with 43 studies completed or under way, and four more studies set to begin this year. There are about 6,700 patients in the Company's clinical studies with about 4,700 of these patients being treated with JANUVIA. Additionally, about 1,100 patients have been treated with JANUVIA for more than a year.

About Merck

Merck & Co., Inc., which operates in many countries as MSD (Merck Sharp & Dohme), 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.

Forwarding-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 cautionary statements in Item 1 of Merck's Form 10-K for the year ended Dec. 31, 2005, and in its periodic reports on Form 10-Q and Form 8-K, which the company incorporates by reference.

(*)Frequencies are defined as: very common (eN 1/10); common (eN 1/100, < 1/10); uncommon (eN 1/1,000, < 1/100); rare (eN 1/10,000, < 1/1,000); and very rare (< 1/10,000).

(1)JANUVIA is a registered trademark of Merck & Co., Inc., which operates in many countries as MSD (Merck, Sharp & Dohme).