The data, presented at the 2006 American Society of Clinical Oncology (ASCO) annual meeting, add to the growing body of evidence supporting the vaccine’s ability to provide strong and sustained immune response in women of all ages.
In the phase III study, 100% of women across all study age groups (15-55 years of age) vaccinated with GSK’s cervical cancer candidate vaccine demonstrated antibody response against HPV 16 and HPV 18 – the two most common cancer-causing HPV types – one month after completion of the vaccination course.
All women remained seropositive when evaluated at 12 months after the first dose, with antibody levels substantially higher than those reported following natural infection.
These new results suggest that women over 25 years old could also be protected from infection with HPV types 16 and 18 through vaccination. The antibody levels were indeed greater or equal to those observed during a separate long-term follow up efficacy study in which women (aged 15 to 25) were shown to have 100% protection over 4.5 years against HPV 16 and 18 infections and associated cervical lesions.
The data also show that GSK’s cervical cancer candidate vaccine was generally safe and well-tolerated in women of all study age groups, extending the safety profile already demonstrated in former studies.
“These results are encouraging as they open the possibility that all women, regardless of age, would benefit from vaccination against oncogenic HPV infection to protect them against cervical cancer,” said Dr Philippe Monteyne, head of global vaccine development of GSK Biologicals.