What is the recommended dosage of Gardasil 9 (Human Papillomavirus 9-valent Vaccine) for adults?

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Gardasil 9 Dosing Schedule for Adults

For adults aged 15-26 years, Gardasil 9 should be administered as a 3-dose schedule with injections at 0,1-2, and 6 months. 1

Dosing Schedule Based on Age

The recommended dosing schedule for Gardasil 9 varies by age:

  • Ages 9-14 years: 2-dose schedule (0,6-12 months)
  • Ages 15-26 years: 3-dose schedule (0,1-2,6 months)
  • Ages 27-45 years: 3-dose schedule (0,1-2,6 months) - with shared clinical decision-making

Special Populations

  • Immunocompromised individuals: 3-dose schedule regardless of age
  • Men who have sex with men: Recommended through age 26 years (3-dose schedule if ≥15 years)

Administration Details

Gardasil 9 is administered as a 0.5 mL intramuscular injection. Each dose contains HPV L1 proteins for types 6,11,16,18,31,33,45,52, and 58 adsorbed on amorphous aluminum hydroxyphosphate sulfate adjuvant 2.

Important Considerations

  1. Catch-up vaccination: The CDC recommends catch-up HPV vaccination for all persons through age 26 years who are not adequately vaccinated 1.

  2. Adults 27-45 years: Vaccination is not routinely recommended for all adults aged >26 years, but shared clinical decision-making is recommended for those aged 27-45 years 1.

  3. Older adults: HPV vaccination is not licensed for use in adults >45 years 1.

  4. Completion of series: If vaccination is interrupted, the series does not need to be restarted. Simply continue with the remaining doses.

  5. Previous vaccination: There is no recommendation for revaccination for those who previously completed a full series with other HPV vaccine formulations 3.

Clinical Pearls

  • HPV vaccines are prophylactic (prevent new infections) but do not treat existing HPV infections or HPV-related disease 1.
  • The highest antibody responses occur in ages 9-15 years, with protection lasting at least 5 years without evidence of waning 1.
  • HPV vaccination does not eliminate the need for cervical cancer screening, and vaccinated individuals should continue screening per guidelines 1.

Common Pitfalls to Avoid

  • Incorrect dosing interval: Ensure proper spacing between doses for maximum efficacy.
  • Assuming therapeutic effect: Remember that HPV vaccines prevent new infections but do not treat existing HPV infections or associated diseases 4.
  • Neglecting special populations: Immunocompromised individuals require a 3-dose schedule regardless of age 1.
  • Overlooking contraindications: Do not administer to individuals with severe allergic reactions to a previous dose or to yeast 1.

By following these guidelines, you can ensure appropriate administration of Gardasil 9 for adult patients, maximizing protection against HPV-related diseases.

References

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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