Merck Launches SAFLUTAN® (tafluprost) in International Markets

Merck & Co., Inc. has launched SAFLUTAN^® (tafluprost) in the United Kingdom and Spain, and additional launches in other countries are expected over the next several months, pending regulatory approvals, the Company said today. SAFLUTAN is a preservative free, synthetic analogue of the prostaglandin F_2a for the reduction of elevated intraocular pressure (IOP) in appropriate patients with primary open-angle glaucoma and ocular hypertension. SAFLUTAN is in Phase III in the U.S.

On April 15, 2009, Merck & Co., Inc. and Santen Pharmaceutical Co., Ltd. announced a worldwide licensing agreement for tafluprost. Under the terms of the agreement, Merck agreed to pay an undisclosed fee as well as milestones and royalty payments based on future sales of tafluprost (both preserved and preservative-free formulations) in exchange for exclusive commercial rights to tafluprost in Western Europe (excluding Germany), North America, South America and Africa. Santen will retain commercial rights to tafluprost in most countries in Eastern Europe, northern Europe and in countries in the Asia Pacific region, including Japan. Merck will provide promotion support to Santen in Germany and Poland. If tafluprost is approved in the U.S., Santen will have the option to co-promote it there.

"Merck is pleased that we are now able to begin supplying SAFLUTAN in approved markets to continue Merck's long standing commitment to ophthalmology and the patients who suffer from ophthalmic diseases worldwide," said Dr. Vlad Hogenhuis, Senior Vice President of Neuroscience and Ophthalmics, Merck & Co., Inc.

Glaucoma consists of a group of diseases that can damage the eye’s optic nerve and can be associated with elevated intraocular pressure.¹ Primary open-angle glaucoma is the most common form of glaucoma.

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, 2008, and in any risk factors or cautionary statements contained in the Company's periodic reports on Form 10-Q or current reports on Form 8-K, which the Company incorporates by reference.

¹ http://www.nei.nih.gov/health/glaucoma/glaucoma_facts.asp

SAFLUTAN^® is a registered trademark of Merck & Co., Inc.