Merck & Co. Inc. and PATH have joined hands to conduct clinical studies of Merck's investigational rotavirus vaccine, Rotateq (rotavirus vaccine, live, oral, pentavalent), in some of the world's developing nations. The trials are one step in the process of making a rotavirus vaccine available in these regions as quickly as possible.

Clinical trial sites will be identified in Africa and Asia over the next six months, with a goal of starting at least one trial by the end of 2006. Efficacy studies of Rotateq will be conducted in regions of the world where it has not been studied before and where factors including poor nutrition and the presence of various intestinal bacteria or viruses might play a role in the response to the vaccine. The studies also will assess how Rotateq fits into the range of childhood vaccine schedules used in different countries, states a Merck release.

"Although rotavirus infection is as common in developed countries as it is in developing nations, most of the children who die from the effects of rotavirus live in countries where emergency medical care, such as intravenous rehydration, is often less readily available. Merck is as committed to identifying innovative ways to bring our vaccines to children in the developing world as we are to developing the innovative vaccines themselves," said, Adel A.F. Mahmoud, chief medical advisor, vaccines and infectious diseases, Merck & Co. Inc.

"We are pleased to partner with Merck on this important initiative and it is our hope that demonstrating the impact of rotavirus vaccines in developing countries will ultimately reduce the potentially serious effects of this disease on children. By pooling our collective strengths, we seek to address one of the most serious public health problems affecting infants and young children worldwide," said John Wecker, director of PATH's Rotavirus Vaccine Programme.

Rotateq is Merck's investigational vaccine to protect against rotavirus gastroenteritis. Rotateq is an oral, liquid vaccine that contains five rotavirus strains - G1, G2, G3, G4 and P1. These serotypes cause most rotavirus disease worldwide. Merck has submitted an application for licensure of Rotateq in more than 50 countries worldwide, including the United States and the European Union.

Rotavirus is the most common cause of severe dehydrating diarrhoea in infants and young children. Among children under five, it has been estimated to be responsible for an estimated two million hospitalisations, 500,000 deaths and more than 25 million clinic visits worldwide each year.

PATH is an international, non-profit organisation that creates sustainable, culturally relevant solutions, enabling communities worldwide to break longstanding cycles of poor health.