Merck Highlights Ongoing Commitment to Developing Drugs Targeting Infectious Disease at 50th Annual ICAAC

WHITEHOUSE STATION N.J. - Merck today reaffirmed its commitment to discovering and developing novel medicines and vaccines for a broad range of infectious diseases at the 50th Annual Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC) being held in Boston.

At the conference, in addition to clinical data on late stage compounds, Merck scientists and their collaborators are scheduled to present results from studies of novel investigational antibiotic and antifungal agent candidates.

“The apparent rise in emerging pathogens and recent evidence of bacterial resistance to some current therapies underscores the important need for continued innovation in the ways we fight infectious disease" said Roger Pomerantz, MD, senior vice president, and Global Franchise Head, Infectious Diseases, Merck Research Laboratories. “Merck continues to build on its legacy of breakthroughs in this critical area and remains committed to the development of a broad portfolio of investigational anti-infective agents designed to treat viral, bacterial, fungal and parasitic infections.”

Studies will be presented of MK-7655 a developmental beta-lactamase inhibitor that has shown activity against class A and class C carbapenemases, which are increasing in prevalence worldwide and are believed to play a significant role in bacterial resistance. Preclinical data from a series of in vitro and in vivo studies to be presented at ICAAC show that MK-7655 may restore the activity of a commonly used antibiotic agent for serious infections against some resistant strains including Pseudomonas aeruginosa, Klebsiella pneumoniae and Citrobacter freundii. In addition studies will be presented for the antifungal candidate MK-3118 an oral glucan synthase inhibitor currently in early phase development for fungal infections.

Select presentations of investigational candidates-

Antibacterial

F1-2141- MK-7655 Human Dose Projection based on Its Pharmacokinetics in Preclinical Species
Wednesday Sept 15 2010, 9 am to-11 am

F1-2138- In Vitro activity of Imipenem alone and in combination with MK-7655: A New Beta- Lactamase Inhibitor
Wednesday Sept 15 2010, 9 am to 11 am

F1-2142- Pharmacodynamics of Imipenem in Combination with MK-7655, a Beta-Lactamase Inhibitor, in the Neutropenic Mouse Thigh Model
Wednesday Sept 15 2010, 9 am to 11 am

F1-2140- In vivo Efficacy of the Beta-Lactamase inhibitor, MK-7655, in combination with Imipenem in Murine Models of Infection.
Wednesday Sept 15 2010, 9 am to 11 am

F1-2139- In vitro Activity of the Class A and C β-lactamase Inhibitor MK-7655
Wednesday Sept 15 2010, 9:00 am to 11:00 am

F1-1967- A Phase I Study Evaluating the Safety, Tolerability, and Pharmacokinetics of an Intravenous Beta-Lactamase Inhibitor in Healthy Male Volunteers
Wednesday Sept 15 2010, 8:45 am to 9:00 am.

F1-2143- In Vitro Activity of MK-7655 in Combination with Imipenem (IPM) against Carbapenem Resistant Gram-Negative Bacteria
SMART Study (presented by principal investigators)

Antifungal

F1-845- “Enfumafungin Derivatives: Orally Active Glucan Synthase Inhibitors,”
Monday, September 13, 2010, 11:15 am to 1:15 pm

F1-846- “Enfumafungin Derivatives: Orally Active Glucan Synthase Inhibitors,”
Monday, September 13, 2010, 11:15 am to 1:15 pm

F1-849- Evaluation of Enfumafungin Derivative MK-3118 in Two Mouse Models of Disseminated Aspergillosis
Monday, September 13 2010, 11:15 am to 1:15 pm

F1-847- MK-3118, An Oral Enfumafungin with Potent in Vitro Activity Against Candida and Aspergillus spp.
Monday, September 13 2010, 11:15 am to 1:15 pm

F1-848- Evaluation of Orally Active Enfumafungin Derivative MK-3118 in Mouse Models of Disseminated Candidiasis
Monday, September 13 2010, 11:15 am to 1:15 pm

F1-1975- A Phase I Single Rising Dose Study Evaluating the Safety, Tolerability and Pharmacokinetics of an Oral Glucan Synthase Inhibitor in Healthy Male Volunteers
Wednesday, September 15 2010, 10:30 am to 10:45 am

Merck’s anti-infective disease pipeline
Merck currently has seven disclosed candidate therapies and vaccines in Phase 2 and Phase 3 clinical development. Merck is developing MK-3415A, an investigational fully human monoclonal antibody combination developed to target and neutralize Clostridium difficile toxins A and B, for the treatment of C. difficile infection. C. difficile infection is an infection of the colon that occurs mainly among individuals who have been using antibiotics and is most commonly acquired by patients while they are in the hospital.

Over the past two decades, Merck has launched nearly 15 vaccines, many of which were the first of their kind. Today Merck is building on its rich heritage of research and development to deliver the next generation of innovative vaccines, including novel investigational vaccines such as a vaccine candidate to target Staphylococcus aureus (V710). Staphylococcus aureus, also known as Staph, is a common bacterium that can cause deadly infections. Merck scientists are also developing vaccines to prevent other life-threatening illnesses including pneumonia (V419).

Fighting infectious disease globally
Overall, Merck’s R&D is closely aligned with global needs, and addresses more than half of the global burdens of illness defined by the World Health Organization (WHO). Working with numerous partners over many years, Merck has research programs relating to significant burdens of illness in the developing world, including malaria, tuberculosis, diarrheal disease, cervical cancer, and HIV and AIDS (including for pediatric use). Merck recently announced plans to initiate a Phase II investigational proof-of-concept clinical study of to evaluate its oral antifungal agent posaconazole for the treatment of chronic Chagas disease. Chronic Chagas Disease is recognized by the World Health Organization as one of the world’s neglected tropical diseases.

In September 2009, Merck and the Wellcome Trust announced the creation of the MSD Wellcome Trust Hilleman Laboratories (www.hillemanlaboratories.in), the first of its kind research and development joint venture with a not-for-profit mission that focuses on developing affordable vaccines to prevent diseases that commonly affect low-income countries.

About Merck
Today’s Merck is a global healthcare leader working to help the world be well. Merck is known as MSD (Merck Sharp & Dohme) outside the United States and Canada. Through our prescription medicines, vaccines, biologic therapies, and consumer care and animal health products, we work with customers and operate in more than 140 countries to deliver innovative health solutions. We also demonstrate our commitment to increasing access to healthcare through far-reaching policies, programs and partnerships. For more information, visit www.merck.com.

Forward-Looking Statement
This news release includes “forward-looking statements” within the meaning of the safe harbor provisions of the United States Private Securities Litigation Reform Act of 1995. Such statements may include, but are not limited to, statements about the benefits of the merger between Merck and Schering-Plough, including future financial and operating results, the combined company’s plans, objectives, expectations and intentions and other statements that are not historical facts. Such statements are based upon the current beliefs and expectations of Merck’s management and are subject to significant risks and uncertainties. Actual results may differ from those set forth in the forward-looking statements.

The following factors, among others, could cause actual results to differ from those set forth in the forward-looking statements: the possibility that the expected synergies from the merger of Merck and Schering-Plough will not be realized, or will not be realized within the expected time period; the impact of pharmaceutical industry regulation and health care legislation; the risk that the businesses will not be integrated successfully; disruption from the merger making it more difficult to maintain business and operational relationships; Merck’s ability to accurately predict future market conditions; dependence on the effectiveness of Merck’s patents and other protections for innovative products; the risk of new and changing regulation and health policies in the U.S. and internationally and the exposure to litigation and/or regulatory actions.

Merck undertakes no obligation to publicly update any forward-looking statement, whether as a result of new information, future events or otherwise. Additional factors that could cause results to differ materially from those described in the forward-looking statements can be found in Merck’s 2009 Annual Report on Form 10-K and the company’s other filings with the Securities and Exchange Commission (SEC) available at the SEC’s Internet site (www.sec.gov).