Merck & Co's RotaTeq (rotavirus vaccine, live, oral, pentavalent)

The FDA has approved Merck & Co'sRotaTeq (rotavirus vaccine, live, oral, pentavalent).RotaTeq is indicated for infantsand children for the prevention of rotavirusgastroenteritis from the G1, G2,G3, and G4 rotavirus serotypes.¹

RotaTeq is an orally administered vaccinegiven as a series of 3 subsequentdoses. The initial dose should be given at6 to 12 weeks of age, with the followingdoses given at 4-to 10-week intervals.The final dose should be given before 32weeks of age.¹ To enhance patient convenienceand compliance, many providersrecommend administering thevaccine at the 2-, 4-, and 6-month wellbabyvisits.² RotaTeq is available as aready-to-administer oral solution in alatex-free dosing tube.¹

The exact mechanism of RotaTeq isunknown. The live oral vaccine has beenshown, however, to replicate in the smallintestine, thus creating immunity in thepatient.

About Rotavirus

Initially discovered in 1973, rotavirusgastroenteritis is a leading cause of severediarrhea, vomiting, fever, and dehydrationin infants and young children.^3,4 It is mostcommon in children between ages 6 and24 months. An estimated 95% of allinfants and children are infected by 5years of age.^1,2 Symptoms of rotavirusinfection after age 5 are rare, probably asa result of prior infections with rotavirus,which eventually lead to resistance.

In temperate climates, cases ofrotavirus gastroenteritis tend to be morecommon in the colder seasons. In tropicalregions, however, rotavirus gastroenteritishas been noted to occur year-round.³

Various strains of rotavirus exist, andclassification of the viruses is based ontheir 2 outer capsid proteins: VP7, whichis also referred to as G protein, and VP4,also referred to as P protein. Althoughstrain types vary by year and location,the most common strains include G1, G2,G3, G4, and G9.³

In the United States each year, rotavirusinfection is responsible for >400,000 doctorvisits, 200,000 emergency departmentvisits, 55,000 to 70,000 hospitalizations,and 20 to 60 deaths of children under age5.⁴Worldwide, ~400,000 children die fromrotavirus each year, accounting for about5% of all childhood deaths.³

Due to the severe complications ofrotavirus gastroenteritis, the Centers forDisease Control and Prevention's (CDC)Advisory Committee on ImmunizationPractices has recommended that RotaTeqbecome included in the CDC's Vaccinesfor Children (VFC) program. The VFC programprovides vaccines to un-or underinsuredchildren.²

Clinical Trials

RotaTeq was evaluated in 72,324infants in 3 placebo-controlled, phase3 clinical studies. The vaccine wasadministered to healthy infants, withthe first dose given between age 6and 12 weeks and the following 2doses at 4-to 10-week intervals. The finaldose was administered before age 32weeks. End points evaluated in the trialwere the incidence of any severity ofrotavirus gastroenteritis, the incidence ofsevere rotavirus gastroenteritis, androtavirus-related hospitalization rates.RotaTeq was found to prevent ~74% of allrotavirus gastroenteritis cases and ~98%of severe cases. Additionally, 95% ofrotavirus-related hospitalizations wereprevented in the RotaTeq group.^1,4

Safety

Diarrhea, vomiting, fever, runny nose,sore throat, wheezing, coughing, and earinfection were the most common sideeffects after vaccination with RotaTeq.RotaTeq should not be given to immunocompromisedinfants or to infants with aknown hypersensitivity to the product.Unless the benefit outweighs the risk,infants with a fever >100.5º F (38.1º C)should not receive RotaTeq.

Patient Education

Protection against rotavirus gastroenteritisafter 1 or 2 doses has not beendetermined. Unless circumstances preventit, parents should be encouraged tocomplete the RotaTeq series. As with allvaccines, vaccination with RotaTeq doesnot guarantee complete protection fromrotavirus gastroenteritis, nor does it protectagainst gastroenteritis caused byviruses other than rotavirus.¹

Dr. Holmberg is a pharmacist withPhoenix Children's Hospital, Phoenix,Ariz.

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