VARIVAX [Varicella Virus Vaccine Live (Oka/Merck)] is a preparation of the Oka/Merck strain of live, attenuated varicella virus. The virus was initially obtained from a child with natural varicella, then introduced into human embryonic lung cell cultures, adapted to and propagated in embryonic guinea pig cell cultures and finally propagated in human diploid cell cultures (WI-38). Further passage of the virus for varicella vaccine was performed at Merck Research Laboratories (MRL) in human diploid cell cultures (MRC-5) that were free of adventitious agents. This live, attenuated varicella vaccine is a lyophilized preparation containing sucrose, phosphate, glutamate, and processed gelatin as stabilizers.
VARIVAX is indicated for vaccination against varicella in individuals 12 months of age and older.
The duration of protection of VARIVAX is unknown at present and the need for booster doses is not defined. However, a boost in antibody levels has been observed in vaccinees following exposure to natural varicella as well as following a booster dose of VARIVAX administered four to six years postvaccination.
In a highly vaccinated population, immunity for some individuals may wane due to lack of exposure to natural varicella as a result of shifting epidemiology. Post-marketing surveillance studies are ongoing to evaluate the need and timing for booster vaccination.
Vaccination with VARIVAX may not result in protection of all healthy, susceptible children, adolescents, and adults (see CLINICAL PHARMACOLOGY).
Published Studies Related to Varivax (Varicella Vaccine)
Immunogenicity and safety of a measles-mumps-rubella-varicella vaccine following a 4-week or a 12-month interval between two doses. [2011.05.17]
BACKGROUND: The MMRV combination vaccine, Priorix-Tetra, is currently licensed in several European countries using a two-dose schedule in infants aged >/=9 months, with a preferred 6-week to 3-month interval between doses. This study was undertaken to generate safety and immunogenicity data for two doses of MMRV vaccine administered according to dose schedules using the shortest permitted interval of 4 weeks versus a longer interval of 12 months, which would allow flexible adaptation to local immunization calendars... CONCLUSIONS: Two doses of MMRV vaccine administered in the second year of life elicited adequate immunogenicity and were well-tolerated whether administered with a dose interval of 4 weeks or 12 months. Copyright (c) 2011. Published by Elsevier Ltd.
Effectiveness of 2 doses of varicella vaccine in children. [2011.02.01]
BACKGROUND: Because of ongoing outbreaks of varicella, a second dose of varicella vaccine was added to the routine immunization schedule for children in June 2006 by the Centers for Disease Control and Prevention... CONCLUSION: The effectiveness of 2 doses of varicella vaccine in the first 2.5 years after recommendation of a routine second dose of the vaccine for children is excellent. Odds of developing varicella were 95% lower for children who received 2 doses compared with 1 dose of varicella vaccine.
Varicella-related hospitalizations in the United States, 2000-2006: the 1-dose varicella vaccination era. [2011.02]
OBJECTIVE: To describe the effect of the mature 1-dose varicella vaccination program on varicella morbidity, we analyzed 2 national databases for varicella-related hospitalizations in the United States since implementation of the varicella vaccination program in 1995... CONCLUSIONS: Varicella-related hospitalization numbers and rates declined significantly during the 1-dose varicella vaccination era. Assuming declines in varicella-related hospitalizations are due, mainly, to the routine childhood varicella vaccination program, these data suggest that varicella vaccination prevented approximately 50,000 varicella-related hospitalizations in the United States from 2000 to 2006.
Association between varicella zoster virus infection and atopic dermatitis in early and late childhood: a case-control study. [2010.08]
BACKGROUND: Wild-type varicella zoster virus infection (WTVZV) early in childhood has been shown to protect against the development of asthma and atopy. OBJECTIVE: To determine whether WTVZV in childhood protects against atopic dermatitis (AD)... CONCLUSION: WTVZV in childhood protects up to 10 years of age against AD, delays onset of AD symptoms, and decreases AD severity and office visits. Copyright 2010 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.
Safety, immunogenicity and immediate pain of intramuscular versus subcutaneous administration of a measles-mumps-rubella-varicella vaccine to children aged 11-21 months. [2010.08]
This study compared intramuscular and subcutaneous administration of two doses of measles-mumps-rubella-varicella (MMRV) combination vaccine (Priorix-Tetra, GlaxoSmithKline Biologicals) in children. Healthy children (N = 328) were randomised to receive MMRV either intramuscularly or subcutaneously...
Clinical Trials Related to Varivax (Varicella Vaccine)
Safety,Tolerability and Immunogenicity of Vaccination With Varivax in Healthy Indian Children [Completed]
A Study of the Safety and Effectiveness of a Chickenpox Vaccine in HIV-Infected Children [Completed]
The purpose of this study is to see if it is safe to give Varivax to HIV-positive children
and whether it protects children from infection. Varivax is a vaccine against varicella
zoster virus (VZV), the virus that causes chickenpox (varicella) and shingles (zoster).
VZV can cause many serious complications in HIV-infected children. Varivax is a VZV vaccine
that has been approved for use in healthy children. More research is needed to find out how
this vaccine will affect HIV-infected children.
A Study of the Safety and Effectiveness of Varivax (the Chicken Pox Vaccine) in Children Who Have Received Kidney Transplants [Completed]
The purpose of this study is to find out whether Varivax is safe for use in children with
kidney transplants and whether it protects children from serious infection. Varivax is a
vaccine against varicella zoster virus (VZV), the virus that causes chicken pox (varicella)
and shingles (zoster).
Healthy children are already receiving Varivax shots to protect them from chicken pox. Few
children with kidney transplants have received Varivax because doctors have been concerned
that Varivax might cause serious reactions in them. On the other hand, VZV infection can be a
life-threatening disease in these children. For this reason, doctors want to learn whether
Varivax might safely prevent VZV infections in children who have had kidney transplants.
The Safety of Oka Varicella in Children Prior to Solid Organ Transplantation [Active, not recruiting]
We hypothesize that children listed to undergo solid organ transplant will experience (at the
very most) a low rate (< 5%) of serious vaccine-related adverse events within 42 days after
immunization with live attenuated Oka/Merck varicella vaccine (VARIVAX™). We also hypothesize
that the immunogenicity of two doses of VARIVAX™ in the study population will be similar to
historical data in healthy subjects and that the efficacy of two doses of the vaccine in the
study population will be similar to that of healthy subjects.
Immunogenicity and Safety of Concomitant Administration of MMRâ¢ rHA and VARIVAX® by Intramuscular Versus Subcutaneous Route [Completed]
To compare if, when given concomitantly with VARIVAX® by the same route at 12-18 months of
age using separate injection sites, a single dose of M-M-RTMII administered by IM route is as
immunogenic as a single dose of M-M-RTMII administered by SC route in terms of response rates
to measles, mumps and rubella at 42 days following the vaccination.
To compare if, when given concomitantly with M-M-RTMII by the same route at 12-18 months of
age using separate injection sites, a single dose of VARIVAX® administered by IM route is as
immunogenic as a single dose of VARIVAX® administered by SC route in terms of response rate
to varicella at 42 days following the vaccination
- To summarise the antibody titres to measles, mumps, rubella and varicella at 42 days
following the vaccination in children immunised with M-M-Râ¢II and VARIVAXÂ® administered
concomitantly at two separate injection sites by the same route IM or SC,
- To evaluate the safety profiles of M-M-Râ¢II and VARIVAXÂ® administered concomitantly at
two separate injection sites by the same route IM or SC.