Merck Again Reduces Price of STOCRIN (efavirenz) for Patients in Least Developed Countries and Countries Hardest Hit by Epidemic; Double-Digit Reduction Helps Expand Access to HIV/AIDS Care and Treatment.

WHITEHOUSE STATION, N.J. -- On the fifth anniversary of the announcement of its worldwide HIV/AIDS pricing policy, Merck & Co., Inc.(1) today further reduced the price of its HIV/AIDS medicine, STOCRIN (efavirenz), in the least developed countries of the world and those hardest hit by the epidemic. The price of the 600 mg formulation of STOCRIN has been reduced by 20 percent to US $0.76 per day, or US $277.40 per patient per year, from $0.95 per day. The 200 mg formulation of STOCRIN has been reduced by 22 percent to US $0.36 per capsule, or $1.08 per day and about US $394.20 per patient per year, from $0.46 per capsule. Merck is lowering the price of these formulations of STOCRIN due to new efficiencies and cost savings resulting from improved manufacturing processes.

"Merck has long been a leader in efforts to broaden access to our medicines for those who need them around the world," said Merck Chief Executive Officer and President Richard T. Clark. "Today's price reductions reflect our commitment to improving the lives of people living with HIV/AIDS throughout the developing world. We hope to be able to reduce the price of STOCRIN again in the future as we continue to achieve efficiencies in our manufacturing processes."

At the end of 2005, nearly 500,000 patients in 76 developing countries were being treated with antiretroviral regimens containing either of Merck's two current HIV/AIDS medicines, STOCRIN and CRIXIVAN (indinavir sulfate).

"This announcement of further price reductions by Merck is very welcome," said Dr. Peter Piot, Executive Director of the Joint United Nations Program on HIV/AIDS (UNAIDS). "The cost of antiretroviral therapies from both research-based and generic pharmaceutical companies has declined dramatically in recent years. We hope that this trend accelerates as the global community gears up to come as close as possible to universal access to HIV prevention, treatment and care for all who need it by 2010."

Merck pricing policy for its HIV/AIDS medicines

The new prices of $0.76 per day for 600 mg STOCRIN and $0.36 per capsule for 200 mg STOCRIN will be available to countries in the low category of the Human Development Index (HDI) - as defined by the United Nations Development Program (UNDP) - and in medium HDI countries with an adult HIV prevalence rate of 1 percent or greater as reported by UNAIDS. For medium HDI countries with an adult HIV prevalence rate of less than 1 percent, the price of STOCRIN 600 mg will be reduced to $1.91 per tablet per day, or $697.15 per patient per year, and the price of STOCRIN 200 mg will be reduced to $0.75 per capsule, or $2.25 per day and $821.25 per year.

These prices are available to all HIV/AIDS care and treatment providers who can demonstrate with reasonable assurance their capacity to ensure increased patient access. Providers include, for example, governments, international organizations, non-governmental organizations (NGOs) and private sector organizations (such as employers, insurers and hospitals). Under the Merck HIV/AIDS pricing policy, the medicines must be used in the country where they are sold and may not be exported.

Five-year anniversary of Merck's HIV/AIDS pricing policy

Today's announcement comes five years to the day, March 7, 2001, since Merck first announced that it was reducing the prices of STOCRIN and CRIXIVAN in developing countries to prices at which the Company makes no profit. Since the Company's announcement, access to HIV medicines has accelerated in the least developed countries and those countries where HIV/AIDS has hit hardest. Merck was able to offer a further price reduction in October 2002 when it launched the 600 mg formulation of STOCRIN.

"The complex challenge of ensuring access to medicines, vaccines and quality health care in the developing world requires multifaceted approaches and solutions," said Per Wold-Olsen, President, Human Health Intercontinental, Merck. "Access to medicines can be limited by inadequate health system infrastructure, a shortage of trained health care workers, difficulties in supply chain management, social stigma and discrimination, and a lack of political will. A sustainable response will come from comprehensive approaches that draw on the complementary expertise and resources of all stakeholders - communities directly affected by the epidemic, governments, the private sector, foundations, international organizations and NGOs alike."

Improving Access Through Public-Private Partnerships

In addition to Merck's ongoing HIV/AIDS antiretroviral and vaccine research programs, the Company continues to work in many public-private partnerships focused on increasing access to treatment and care. These partnerships play a critical role in the developing world by helping to build the health systems capacity necessary to ensure sustainable access to health care and treatment. Some of these programs include: African Comprehensive HIV/AIDS Partnerships (ACHAP) in Botswana, Merck Mectizan Donation Program, China-MSD HIV/AIDS Partnership, Merck Vaccine Network-Africa and Merck Medical Outreach Program (MMOP).*

(*MEDIA NOTE: See attached for details about these public-private partnership programs.)

About STOCRIN

STOCRIN is a once-daily, non-nucleoside reverse transcriptase inhibitor (NNRTI) used in combination treatment for HIV. People living with HIV/AIDS have the option of taking one 600 mg STOCRIN tablet once-daily instead of three 200 mg capsules. The 600 mg tablet is approved in more than 90 countries.

STOCRIN in combination with other antiretroviral agents is indicated for the treatment of HIV-1 infection. This indication is based on two clinical trials of at least one-year duration that demonstrated prolonged suppression of HIV-RNA.

STOCRIN should not be administered concurrently with astemizole, cisapride, triazolam, midazolam, or ergot derivatives because competition for CYP3A4 by efavirenz could result in inhibition of metabolism of these drugs and create the potential for serious and/or life-threatening adverse events (e.g., cardiac arrhythmias, prolonged sedation or respiratory depression).

The chemical entity of STOCRIN, efavirenz, was discovered by the Merck Research Laboratories in 1992 and licensed to The DuPont Merck Pharmaceutical Company (now Bristol-Myers Squibb Company) in 1994 for development and marketing in certain countries. Bristol-Myers Squibb has exclusive marketing rights to efavirenz in the United States (including territories and possessions), Canada, United Kingdom, Republic of Ireland, France (continental only), Spain, Italy and Germany, and markets efavirenz under its trademark Sustiva.

Merck, through its subsidiaries and marketing partners, has exclusive marketing rights to STOCRIN in all other countries worldwide, and markets efavirenz under the trademark STOCRIN.

About Merck

Merck & Co., Inc., which operates outside the United States as Merck Sharp & Dohme (MSD), is a global research-driven pharmaceutical company dedicated to putting patients first. Established in 1891, Merck 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 also 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 cautionary statements in Item 1 of Merck's Form 10-K for the year ended Dec. 31, 2004, and in its periodic reports on Form 10-Q and Form 8-K, which the Company incorporates by reference.

(NOTE TO REPORTERS/EDITORS: The following are examples of major Merck Programs and Partnerships in the area of global health.)

--The African Comprehensive HIV/AIDS Partnerships (ACHAP) - Established in July 2000, this partnership between the Government of Botswana, the Bill & Melinda Gates Foundation and The Merck Company Foundation/Merck & Co., Inc. works to support and enhance Botswana's national response to HIV/AIDS through a comprehensive approach to prevention, treatment, care and support. The Bill & Melinda Gates Foundation and The Merck Company Foundation are each contributing $50 million to the project over several years. Merck & Co., Inc. is also donating its two antiretroviral medicines to the government's national antiretroviral treatment program, Masa. Web link: www.merck.com/cr or www.achap.org.

--The Merck Mectizan Donation Program - In 1987, Merck committed to donate its drug MECTIZAN(R) (ivermectin), for the treatment onchocerciasis (river blindness), to all who need it for as long as necessary until the disease is eliminated as a public health problem. The program currently reaches more than 45 million people each year in Africa, Latin America and Yemen. In 1998, Merck expanded its commitment to include donations of MECTIZAN for the prevention of lymphatic filariasis (LF) in African countries where LF co-exists with river blindness. Web link: www.merck.com/cr or www.mectizan.org.

--China-MSD HIV/AIDS Partnership - A public-private partnership with China's Ministry of Health to provide HIV/AIDS prevention, patient care, treatment and support was announced in May 2005. The project will focus on a range of interventions including education, counseling, testing, harm reduction and health services, including treatment and care for people living with HIV/AIDS. The program was launched in Sichuan Province in the fall of 2005. Web link: www.merck.com/cr.

--The Merck Vaccine Network-Africa (MVN-A) - Launched in 2003, MVN-A is a multi-year initiative to help increase the capacity of immunization programs to deliver vaccines effectively in Kenya and Mali through training of national and regional health care workers in vaccine management and immunization services. Web link: www.merck.com/cr.

--The Merck Medical Outreach Program (MMOP) - Through the MMOP, Merck donates pharmaceuticals and vaccines to select, qualified, U.S.-based private voluntary organizations (PVOs) for use in the developing world and in support of major disaster relief and emergency situations worldwide. In 2004, Merck donated nearly $431 million in pharmaceuticals and vaccines through the program. Web link: www.merck.com/cr.

(1)Merck & Co., Inc., Whitehouse Station, New Jersey, USA, operates in most countries outside of the United States as Merck Sharp & Dohme (MSD).