OBJECTIVES:~Primary objective:~To test the hypothesis that Gardasil® vaccine, when administered to girls 11-13 years of age according to 1 of 3 alternative 3-dose schedules (0,3,9 months; 0,6,12 months; or 0,12,24 months), results in anti-HPV 16 and anti-HPV 18 responses 28 days post-dose 3 that are similar to those obtained when the vaccine is administered on the standard 3-dose schedule of 0,2,6 months.~Secondary objectives:~To test the hypothesis that Gardasil® vaccine, when administered to girls 11-13 years of age according to 1 of 3 alternative 3-dose schedules (0,3,9 months; 0,6,12 months; or 0,12,24 months), results in anti-HPV 6 and anti-HPV 11 responses 28 days post-dose 3 that are similar to those obtained when the vaccine is administered on the standard 3-dose schedule of 0,2,6 months.~To describe the safety profile of the administration of Gardasil® according to each of the four schedules by assessing:~(i) immediate reactogenicity (reactions within 30 minutes after each injection); (ii) solicited (local reactogenicity and fever) and unsolicited events occurring during the first 7 days following each vaccination; (iii) serious adverse events occurring up to one month following the last dose of vaccine; (iv) deaths or adverse events occurring at any time determined to be vaccination-related.
To demonstrate that Gardasil® vaccine, when given to girls 11-13 years of age according to 1 of 3 alternative 3-dose schedules (0, 3, 9 months; 0, 6, 12 months; or 0, 12, 24 months), results in anti-HPV type 16 and anti-HPV type 18 responses 28 days post-dose 3 that are similar to those obtained when the vaccine is given on the standard 3-dose schedule of 0, 2, 6 months.