Expanded Labelling for Januvia(R) (sitagliptin) Approved by European Commission

Merck Sharp & Dohme (MSD) today announced that the European
Commission has approved ´Januvia´ (sitagliptin) for two additional
uses for patients with type 2 diabetes. This now makes sitagliptin the
only dipeptidyl peptidase-4 inhibitor (DPP-4 inhibitor) approved as an
add-on therapy to a sulphonylurea (´dual therapy´), or a sulphonylurea
plus metformin (´triple therapy´), in the European Union (EU). It
remains the only DPP-4 inhibitor indicated for once-daily use.

With this new approval for the two additional uses, the product is
now indicated to improve glycaemic control in combination with a
sulphonylurea when diet and exercise plus maximal tolerated dose of a
sulphonylurea alone do not provide adequate glycaemic control, and
when metformin is inappropriate due to contraindications or
intolerance; and to improve glycaemic control in combination with a
sulphonylurea and metformin when diet and exercise plus dual therapy
with these agents do not provide adequate glycaemic control.

Sitagliptin was approved in the European Union in March 2007 for
the treatment of type 2 diabetes in combination with either metformin
or, in certain patients, with a PPAR(gamma) agonist (i.e.
thiazolidinedione) when diet and exercise plus either agent do not
provide adequate glycaemic control. It should not be used in patients
with type 1 diabetes or for the treatment of diabetic ketoacidosis.

"The approval of these new indications is another step forward in
helping to combat type 2 diabetes. It is important because it provides
physicians and patients with more options to achieve reduced glycaemic
levels," said Stefan Oschmann, President, Europe, Middle East, Africa
and Canada, Merck & Co., Inc.

The approval of the indication extensions was based on phase III
clinical trial results supporting the tolerability and efficacy of
sitagliptin 100 mg once-daily in combination with glimepiride (a
sulphonylurea) alone or with glimepiride plus metformin.(1) Overall,
the trial data showed that the addition of sitagliptin significantly
reduced HbA1c levels and fasting plasma glucose levels, and was
generally well tolerated.(1)

In clinical trials in combination with a sulphonylurea
(glimepiride), with or without metformin, sitagliptin demonstrated an
overall incidence of adverse reactions higher than that seen with
placebo, in part related to a higher incidence of hypoglycaemia with
the treatment compared to placebo (12.2 percent vs. 1.8 percent,
respectively). The higher rate of hypoglycaemia is commonly seen when
antihyperglycaemic agents are used in combination with sulphonylurea
agents. When sitagliptin is used in combination with a sulphonylurea,
a lower dose of the sulphonylurea may be considered to reduce the risk
of hypoglycaemia.

In controlled clinical studies in combination therapy with
metformin or pioglitazone, the overall incidence of adverse reactions,
hypoglycaemia, and discontinuation of therapy due to clinical adverse
reactions with sitagliptin were similar to placebo. In these clinical
studies, the most common adverse reactions reported (greater than or
equal to 5 percent and higher than placebo) were stuffy or runny nose
and sore throat, upper respiratory infection, and headache.

Dosing of ´Januvia´

The recommended dose is 100 mg once daily, with or without food,
for all adopted indications.

No dosage adjustment is needed for patients with mild to moderate
hepatic insufficiency. The product has not been studied in patients
with severe hepatic insufficiency. For patients with mild renal
insufficiency (creatinine clearance (CrCl) => 50 ml/min), no dosage
adjustment is required. Clinical study experience in patients with
moderate or severe renal insufficiency is limited. Therefore, use of
sitagliptin is not recommended in this patient population.

No dosage adjustment is necessary based on age. Limited safety
data are available in patients =>75 years of age and care should be
exercised.

No liver function tests need to be performed prior to the
initiation of treatment.

Use in specific populations

Sitagliptin should not be used during pregnancy or during breast
feeding. It is not recommended for use in children below 18 years of
age due to a lack of data on its safety and efficacy.

Worldwide availability

The adoption of the indication extension will be applicable to the
27 countries that are members of the EU, including the United Kingdom,
Germany, France, Italy and Spain. It is estimated that over 53 million
people in Europe have diabetes.(2) It has so far received approval in
more than 60 countries and is available in every region around the
world. As a result of this worldwide availability, there have been
over three million prescriptions for sitagliptin.(3)

Expanding clinical development programme

Merck & Co., Inc.´s clinical development programme for sitagliptin
is robust and continues to expand with 49 studies completed or
underway and five more studies set to begin this year. There have been
more than 9,400 patients in the Company´s clinical studies, with about
6,000 of these patients being treated with the product. Additionally,
about 2,300 patients have been treated with sitagliptin for more than
one year and of these 400 patients have been treated for at least 2
years.

About Merck & Co., Inc., of Whitehouse Station, N.J., U.S.A.

Merck & Co., Inc. which operates in many countries as Merck Sharp
& Dohme or MSD, is a global research-driven pharmaceutical company
dedicated to putting patients first. Established in 1891, the Company
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
programme that not only donate its medicines but help deliver them to
the people who need them. Merck & Co., Inc. 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. MSD 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 MSD´s business, particularly those mentioned in the risk
factors and cautionary statements in Item 1A of MSD´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.

(1) Hermansen K, Kipnes M, Luo E et al. Efficacy and safety of the
dipeptidyl peptidase-4 inhibitor, sitagliptin, in patients with type 2
diabetes mellitus inadequately controlled on glimepiride alone or on
glimepiride and metformin. Diabetes, Obesity and Metabolism 2007
9(5):733-745.

(2) International Diabetes Federation: Diabetes Atlas, 3rd ed.
2006 Chapter 1, p.28.

(3) IMS Health, NPA(TM) Weekly, TRxs, week ending October 20, 2006
- week ending December 21, 2007.

Januvia(R) is a registered trademark of Merck & Co., Inc., of
Whitehouse St, NJ, USA known in many countries as Merck Sharp & Dohme