What is the CVT Vaccination Study?
The CVT Study was a community-based, controlled, double-blind, randomized clinical trial that began in May 2004 and included the participation of 7466 women between the ages of 18 and 25 and residents of the province of Guanacaste, Costa Rica and surrounding areas nearby.
The main objective of this research study was to demonstrate the efficacy of the candidate vaccine compared to the control vaccine in the prevention of CIN2+ (moderate or severe cervical intraepithelial neoplasia, cancer in situ or invasive cervical cancer) histologically confirmed, associated with HPV16 infection or HPV18, occurring after the third dose (from month 6 to month 48), in young adult women negative for HPV DNA by polymerase chain reaction (PCR) at months 0 and 6 for the corresponding type of HPV.
VACCINATION STUDY CVT means:
Phase III study of efficacy of a vaccine against HPV16/18, double-blind, controlled, randomized, for the prevention of advanced cervical neoplasia (CIN2, CIN3, adenocarcinoma in situ [AIS] and invasive cervical cancer), associated with infection by HPV16 or HPV18, in healthy young adult women in Costa Rica
Importance of the
CVT Vaccination Study
Human papillomaviruses (HPV), produce a very common infection, both in men and women, which usually heals on its own, but if it does not heal, it can cause cancer after a long time. Therefore, if a woman has an HPV infection in her cervix, there is a chance that she will develop cervical cancer, and as with other diseases that are caused by viruses, a vaccine can be effective in preventing infection and cancer.
Researchers from the National Institutes of Health of the United States discovered the HPV vaccine based on virus-like particles (VLP), which preclinical studies reliably demonstrated the preventive efficacy of this vaccine in relation to cervical cancer. Therefore, based on these promising findings, the National Cancer Institute (NCI) and ACIB-FUNIN carried out this CVT VACCINATION STUDY in Guanacaste, an area with high rates of cervical cancer and where in 1993 the Natural History Study of HPV and Cervical Neoplasia were carried out also, which demonstrated the association of HPV infection with the development of precancerous lesions and cervical cancer.
Objective of the
CVT Vaccination Study
To demonstrate the efficacy of vaccine candidate compared to control in preventing histopathologically confirmed CIN 2+ associated with cervical HPV16 or HPV18 infection after dose 3 (from month 6 to month 48), in women HPV DNA-negative young adults (by PCR) at months 0 and 6 for the corresponding HPV type of HPV.
(CIN 2+ is defined as cervical intraepithelial neoplasia or preinvasive lesion that produces changes in the transformation zone of the cervix, which can be CIN2 or moderate dysplasia, CIN3 or severe dysplasia, cancer in situ or invasive cervical cancer).
mbios en la zona de transformación del cuello de útero o cérvix, que pueden ser NIC2 o displasia moderada, NIC3 o displasia grave, cáncer in situ o cáncer cervical invasor).
Design of the
CVT Vaccination Study
The CVT STUDY is that of a randomized, double-blind, controlled clinical trial, whose population of interest were women between 18 and 25 years of age, who, to be included in this research study, had to be considered healthy according to medical judgment by the clinical study staff and who were not pregnant at the time of vaccination and were willing to use an effective contraceptive method 30 days before vaccination until 60 days after the last vaccination.
Participants were vaccinated three times over a six-month period (at months 0, 1, and 6) with either the HPV vaccine (Cervarix) or the hepatitis A vaccine (Havrix). At each of these visits, blood samples for evaluation of antibody titers. As part of the active monitoring of participation, each woman made annual visits to the ACIB-FUNIN care centers for four years.
Related Resources
Publications
- Shing JZ, et al. Lesiones cervicales precancerosas causadas por tipos de VPH no prevenibles por vacunación después de la vacunación con la vacuna VPH bivalente con adyuvante AS04: un análisis del estudio de seguimiento a largo plazo del ensayo aleatorizado de vacunas contra el VPH de Costa Rica. Lanceta Oncol
- Porras C, Tsang SH, et al. Eficacia de la vacuna bivalente contra el VPH contra el precáncer asociado al VPH 16/18: resultados del seguimiento a largo plazo del ensayo de vacunas de Costa Rica. Lancet Oncol
- Kreimer AR, Sampson JS, et al. Evaluación de la durabilidad de una dosis única de la vacuna bivalente contra el VPH: el ensayo CVT. JNCI
- Tsang SH, Sampson JS, et al. Durabilidad de la protección cruzada por diferentes esquemas de la vacuna bivalente contra el VPH: el ensayo CVT. JNCI
- Herrero R, Wacholder S, Rodríguez AC, et al. Prevención de la infección persistente por el virus del papiloma humano mediante una vacuna contra el VPH16/18: un ensayo clínico aleatorizado basado en la comunidad en Guanacaste, Costa Rica. Descubrimiento del cáncer
- Herrero R, Hildesheim A, Rodríguez AC, et al. Justificación y diseño de un ensayo clínico aleatorizado doble ciego basado en la comunidad de una vacuna contra el VPH 16 y 18 en Guanacaste, Costa Rica . Vacuna 2008.
Pending publication of results of this scientific research.
Principal Investigators of the CVT VACCINATION STUDY: Rolando Herrero Acosta, Ph.D, ACIB-FUNIN, Allan Hildesheim Ph.D, NCI and Aimée R. Kreimer PhD, NCI
Sponsor: National Cancer Institute of the United States (NCI).
Institutions participating in the ESCUDDO Project: National Cancer Institute of the United States (NCI); Costa Rican Agency for Biomedical Research (ACIB-FUNIN), formerly the Guanacaste Epidemiological Project (PEG).
Approved by the Scientific Ethics Committee: CEC-INCIENSA
Results of Study
