Three-Dose Gardasil Schedule
The three-dose HPV vaccine schedule should be administered at 0,1-2 months, and 6 months for individuals who initiate vaccination at age 15 years or older. 1
Standard Dosing Intervals
The recommended timing for the three-dose series is:
- Dose 1: Initial dose (month 0)
- Dose 2: 1-2 months after the first dose 1
- Dose 3: 6 months after the first dose 1
This creates a 0,1-2,6 month schedule that has been consistently recommended across multiple guideline iterations. 2, 3
Minimum Acceptable Intervals
When the standard schedule cannot be followed, minimum intervals must be maintained:
- Between doses 1 and 2: Minimum of 4 weeks 2, 4, 5
- Between doses 2 and 3: Minimum of 12 weeks 2, 4, 5
- Between doses 1 and 3: Minimum of 24 weeks (approximately 6 months) 3, 5
These minimum intervals represent the absolute shortest acceptable timeframes and should only be used when necessary. 5
Who Requires Three Doses
The three-dose schedule is required for:
- All individuals initiating vaccination at age 15 years or older 1, 2, 3
- All immunocompromised individuals regardless of age at initiation 2, 3, 6
- HIV-positive individuals 7
- Solid organ transplant recipients 2
The critical determining factor is the age when the first dose was administered, not when subsequent doses are given. 2, 3
Managing Interrupted Schedules
The vaccine series should never be restarted regardless of how long the interruption lasts. 2, 3, 4 Key principles include:
- Continue from where you left off without restarting 2, 4
- Administer the next dose as soon as possible 2, 3
- Maintain minimum intervals between remaining doses 2, 4
- No maximum time interval exists between doses 2, 3
This is a common pitfall—providers sometimes unnecessarily restart the series after prolonged interruptions, which wastes doses and delays protection. 2
Evidence Supporting Longer Intervals
Longer intervals between doses produce stronger immune responses than shorter intervals. 2, 3 Specifically:
- A 12-month interval generates more robust antibody responses than a 6-month interval 2, 3
- A 6-month interval is superior to a 2-month interval 2
- Extended intervals (even years) between doses are acceptable and may enhance immunity 2
This evidence supports flexibility in scheduling while maintaining minimum intervals. 2, 5
Clinical Context and Timing Considerations
Vaccination should be completed promptly to maximize protection before potential HPV exposure. 2, 4 Important context includes:
- Approximately 24% of adolescents report sexual intercourse by 9th grade 2, 4
- HPV infection incidence is nearly 60% within 2 years after sexual initiation in males 2
- Vaccination is most effective when given before sexual activity begins 1
However, sexually active individuals should still be vaccinated according to age-based recommendations, as they are unlikely to have been infected with all vaccine HPV types. 1, 2, 3
Prior HPV Exposure
History of genital warts, abnormal Pap tests, or positive HPV DNA tests are not contraindications to vaccination. 1, 2 The vaccine will still provide protection against HPV types not yet acquired. 2, 3
Co-Administration with Other Vaccines
HPV vaccine can be administered at the same visit as other age-appropriate vaccines (such as Tdap and meningococcal vaccines) using separate syringes at different anatomic sites. 2, 3, 4
Safety Precautions
Patients should sit or lie down for 15 minutes after HPV vaccine administration due to the risk of syncope in adolescents following injections. 2, 4