News | March 18, 2010

WHO Extends Prequalification Of Merck's ROTATEQ For Global Use

ROTATEQ (Rotavirus Vaccine, Live, Oral, Pentavalent), the vaccine from Merck that helps prevent rotavirus gastroenteritis in infants and children, has received an extension of its prequalification status by the World Health Organization (WHO), to include its use in Asia and Africa. In October 2008, ROTATEQ received WHO prequalification for its use in Europe and Latin America. Because ROTATEQ is prequalified by the WHO, the vaccine is eligible for procurement by the United Nations Children's Fund (UNICEF) and other United Nations agencies, including the Pan American Health Organization (PAHO), for use in national vaccination programs.

WHO global prequalification for ROTATEQ is based on quality, safety, and efficacy data generated in the United States, Asia, Africa, Latin America, and Europe. The extension of prequalification for use of the vaccine in Asia and Africa is based on data from a clinical trial in these regions done in partnership with PATH, an international non-profit organization. The trial in Asia (Bangladesh and Vietnam) and Africa (Ghana, Kenya and Mali) is complete and the results are expected to be published in the near future.

In the U.S., ROTATEQ is indicated for the prevention of rotavirus gastroenteritis in infants and children caused by serotypes G1, G2, G3 and G4 when administered as a three-dose series to infants between the ages of 6 to 32 weeks. The first dose should be administered between 6 and 12 weeks of age, with the subsequent doses administered at 4 to 10 week intervals. The third dose should not be given after 32 weeks of age.

ROTATEQ should not be administered to infants with a demonstrated history of hypersensitivity to the vaccine or any component of the vaccine. Infants with Severe Combined Immunodeficiency Disease (SCID) should not receive ROTATEQ. Post-marketing reports of gastroenteritis, including severe diarrhea and prolonged shedding of vaccine virus, have been reported in infants who were administered ROTATEQ and later identified as having SCID.

In 2009, WHO recognized the importance of rotavirus vaccination and recommended the inclusion of rotavirus vaccination in all national immunization programs. Expanded access to ROTATEQ is especially important in the world's least developed countries, including those in Asia and Africa, where the consequences of rotavirus gastroenteritis can be very serious due in part to poorer access to healthcare. Rotavirus infects nearly all children worldwide by age 5 and causes approximately 1.9 million hospitalizations each year in developing countries.

"Gaining WHO prequalification status for ROTATEQ in Asia and Africa will help accelerate the availability of the vaccine to infants in the developing world, where the burden of rotavirus disease is very high," said Mark Feinberg, M.D., Ph.D., vice president, Medical Affairs and Policy, Merck Vaccines. "This extension is an important part of Merck's efforts to improve access to ROTATEQ in areas most affected by the severe consequences of rotavirus gastroenteritis."

About Rotavirus
Rotavirus is a leading cause of severe acute gastroenteritis in infants and young children. Rotavirus is highly prevalent and highly contagious, infecting nearly all children by age 5, many more than once, in both developed and developing countries. The virus causes an estimate of more than two million hospitalizations and more than 500,000 deaths worldwide among children under age 5 each year. Eighty percent of rotavirus-related deaths occur in developing countries. In the U.S., historically rotavirus has been responsible for an estimated 55,000 to 70,000 hospitalizations, more than 200,000 emergency room visits, approximately 400,000 doctor visits and approximately 20-60 deaths per year among children under age 5.

About ROTATEQ
ROTATEQ is an oral liquid vaccine requiring no reconstitution or mixing.

The safety profile and efficacy of ROTATEQ were evaluated in Phase 3 studies of more than 71,000 infants from 11 countries and included the landmark Rotavirus Efficacy and Safety Trial (REST), one of the largest pre-licensure vaccine clinical trials ever conducted. Approximately 33 million doses of ROTATEQ have been distributed worldwide through 2009. ROTATEQ has been approved in more than 90 countries around the world.

Select Safety Information about ROTATEQ
No safety or efficacy data are available from clinical trials regarding the administration of ROTATEQ to infants who are potentially immunocompromised.

No safety or efficacy data are available for administration of ROTATEQ to infants with a history of gastrointestinal disorders.

Caution is advised when considering whether to administer ROTATEQ to individuals with immunodeficient contacts.

More than 71,000 infants were evaluated in three Phase 3, placebo-controlled clinical trials. Serious adverse events occurred in 2.4 percent of recipients of ROTATEQ when compared to 2.6 percent of placebo recipients within the 42-day period of a dose of ROTATEQ. Hematochezia, reported as a serious adverse event for ROTATEQ compared to placebo, was less than 0.1 percent vs. less than 0.1 percent. The most frequently reported serious adverse events for ROTATEQ, compared to placebo, were bronchiolitis, gastroenteritis, pneumonia, fever, and urinary tract infection.

In a subset of more than 11,000 infants in these trials, the presence of adverse events was reported for 42 days after each dose. Fever was observed at similar rates in vaccine and placebo recipients (42.6 percent vs. 42.8 percent). Adverse events that occurred at a statistically higher incidence within 42 days of any dose among recipients of ROTATEQ, as compared with placebo recipients, were diarrhea (24.1 percent vs. 21.3 percent), vomiting (15.2 percent vs. 13.6 percent), otitis media (14.5 percent vs. 13.0 percent), nasopharyngitis (6.9 percent vs. 5.8 percent), and bronchospasm (1.1 percent vs. 0.7 percent).

In post-marketing experience, intussusception (including death) and Kawasaki disease have been reported in infants who have received ROTATEQ.

ROTATEQ may not protect all vaccine recipients against rotavirus.

About Merck
Today's Merck is working to help the world be well. Through our medicines, vaccines, biologic therapies, and consumer and animal 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 health care through far-reaching programs that donate and deliver our products to the people who need them. Merck. Be Well. For more information, visit www.merck.com.

SOURCE: Merck