Gardasil

• Primary (approved) indications
• Active immunization for the prevention of premalignant cervical lesions (cervical intraepithelial neoplasia grades 2 and 3; CIN2/3), adenocarcinoma in situ (AIS), and invasive cervical cancer caused by persistent infection with HPV types 16 and 18.
• Prevention of external genital lesions (including condyloma acuminata/genital warts) caused by HPV types 6 and 11.
• Prevention of vulvar and vaginal precancers and cancers associated with HPV-16 and HPV-18 in females.
• Prevention of anal intraepithelial neoplasia and anal cancer associated with HPV-16 and HPV-18 in both females and males.
• Approved age groups and populations
• Licensed for use in females and males starting from the approved lower age limit (commonly age 9 or 10, depending on jurisdiction) through older age ranges defined by local licensure and program recommendations (catch-up cohorts often extend to mid-20s or older by national policy).
• Indicated for both females and males for prevention of HPV-related disease in the genital and anal regions where licensed.
• Important clinically accepted/off-label uses
• Use for prevention of oropharyngeal HPV infection is biologically plausible and the vaccine may reduce risk of HPV-related oropharyngeal disease, but specific labeling and programmatic recommendations vary by jurisdiction.
• Use in special populations (e.g., immunocompromised persons) is often recommended with adjusted schedules; consult local guidance for exact age and dosing recommendations.

• Dose & formulation
• 0.5 mL per dose; intramuscular injection. Preferred site: deltoid muscle for adolescents and adults; anterolateral thigh may be used in young children. Do not administer intravenously, intradermally, or subcutaneously.
• Routine schedules
• Two-dose schedule (preferred for young adolescents): For individuals who begin the series at the younger approved ages (commonly 9–14 years), a 2-dose schedule may be used — Dose 1 at month 0; Dose 2 at month 6 (or as specified by local program guidance; minimum interval requirements apply).
• Three-dose schedule: For individuals who begin the series at older ages (commonly ≥15 years) and for many catch-up or high-risk groups, a 3-dose schedule is used — Dose 1 at month 0; Dose 2 at month 1–2; Dose 3 at month 6 (exact timing may vary by product labeling).
• Immunocompromised persons
• Persons with immunocompromise (including those with HIV infection) generally should receive a 3-dose schedule regardless of age at initiation because immune response may be reduced.
• Male vaccination
• Same schedules apply for males as for females; the vaccine is approved for prevention of genital warts and anal disease in males where licensed.
• Catch-up vaccination
• Catch-up schedules for older adolescents and adults vary by jurisdiction; when starting a schedule late, follow local guidance regarding need for three doses.
• Missed doses
• If a dose is delayed, administer the missed dose as soon as possible. The series does not need to be restarted. If a dose was given earlier than the recommended minimum interval, additional doses may be required per product guidance.
• Administration notes
• Inspect visually and do not use if the vaccine has been frozen, discolored, or contains particulate matter inconsistent with product description. Use aseptic technique and appropriate needle length. Observe vaccinee for 15 minutes post-injection to monitor for syncope.

The quadrivalent HPV vaccine contains recombinant L1 major capsid proteins from HPV types 6, 11, 16, and 18 that self-assemble into non-infectious virus-like particles (VLPs). These VLPs are recognized by antigen-presenting cells and stimulate a robust humoral immune response characterized by high-titer, type-specific neutralizing antibodies. Neutralizing antibodies prevent initial infection by blocking viral attachment and entry into epithelial cells at mucosal surfaces, thereby preventing establishment of persistent infection and the downstream development of premalignant lesions and cancers. The vaccine does not contain live virus and cannot cause HPV infection or integrate into host DNA.

• Absorption/Distribution: As a vaccine, antigenic components remain at the injection site and in regional lymph nodes where they are processed by immune cells; systemic exposure to intact VLPs is minimal. Immune effect is mediated through induction of systemic and mucosal antibodies.
• Metabolism/Elimination: Protein antigens are processed and degraded by proteolytic pathways within antigen-presenting cells and the reticuloendothelial system; breakdown products are handled by standard protein catabolism pathways. There are no small-molecule metabolites requiring hepatic CYP metabolism.
• Onset & duration of protection: Neutralizing antibody responses begin within weeks after initial doses and peak after completion of the primary series. Durable protection has been demonstrated for several years in immunogenicity and effectiveness studies; defined correlates of protection and the need for routine boosters remain areas of ongoing surveillance.

• Pregnancy: Vaccination with the quadrivalent HPV vaccine is not recommended during pregnancy because clinical trials did not include pregnant women to assess efficacy or safety in pregnancy. If pregnancy is discovered after administration of a dose, remaining doses in the series should be postponed until after pregnancy. Available pregnancy registry and observational data have not demonstrated a pattern of adverse pregnancy outcomes attributable to vaccination, but routine avoidance in pregnancy remains recommended.
• Lactation: Limited data indicate no known harmful effects to breastfeeding infants; vaccination may be administered to lactating women if indicated. Clinical judgment should guide use while considering available safety information.
• Data limitations: Longitudinal registry and surveillance data are available but constrained; exercise routine caution and follow national program guidance.

• Primary therapeutic class: Preventive vaccine — Recombinant virus-like particle (VLP) vaccine.
• Subclass: Quadrivalent HPV vaccine targeting HPV types 6, 11 (low-risk, wart-causing) and 16, 18 (high-risk, oncogenic).

• Known hypersensitivity (e.g., anaphylaxis) to any component of the vaccine, including yeast or other excipients.
• Severe allergic reaction to a prior dose of the same HPV vaccine product.
• Vaccination is deferred in pregnancy until after pregnancy is complete.

• Syncope (fainting): Fainting is relatively common among adolescents after vaccination; observe vaccinees for 15 minutes post-injection to prevent injury.
• Anaphylaxis: Facilities and trained personnel to manage anaphylaxis should be available; seek immediate care for severe allergic reactions.
• Immunocompromised persons: May have a reduced immune response; a 3-dose schedule is usually recommended. Clinical counseling and monitoring are appropriate.
• No therapeutic effect on existing infection or disease: The vaccine does not treat existing HPV infection, genital warts, or established premalignant lesions—vaccination prevents future infection.
• Administration precautions: Do not inject intravenously. Inspect vaccine and do not use if frozen or otherwise compromised.
• Monitoring: Report unexpected adverse events to public health surveillance systems. Routine booster dosing is not established; ongoing monitoring informs future policy.

• Very common / common
• Local: pain, erythema, swelling, and induration at the injection site.
• Systemic: headache, fatigue, myalgia, low-grade fever, malaise, gastrointestinal symptoms (nausea).
• Uncommon / rare
• Allergic reactions, including anaphylaxis (rare).
• Neurological events (e.g., reports of Guillain-Barré syndrome) have been investigated in surveillance systems; causal relationships are uncommon and such events are rare.
• Syncope-related traumatic injury following fainting.
• Timing & dose-dependence
• Local and systemic reactogenicity typically begins within 24–48 hours after administration and resolves within a few days. Reactogenicity profiles may vary modestly between doses. Serious adverse events are rare.

• Concomitant vaccines: The quadrivalent HPV vaccine may be administered concomitantly with other vaccines (inactivated or live) at separate anatomical sites; coadministration may modestly affect reactogenicity but is acceptable in routine immunization schedules.
• Drug–drug / drug–food / alcohol interactions: No clinically significant interactions with medications, foods, or alcohol are known because the vaccine acts via immunologic mechanisms and is not metabolized by hepatic enzyme systems.
• Immunosuppressive therapies: Concomitant immunosuppressive therapy may reduce immunogenicity; consider timing of vaccination relative to immunosuppressive treatment and counsel on potential reduced efficacy.

• Dosing flexibility: Many immunization programs now use 2-dose schedules for young adolescents to improve programmatic coverage while preserving immunogenicity; 3-dose schedules remain recommended for older initiators and immunocompromised persons.
• Gender-neutral vaccination: Increasing numbers of national immunization programs recommend gender-neutral vaccination (both males and females) to reduce the burden of HPV-related disease, especially genital warts and anal neoplasia.
• Program transitions: Some jurisdictions have transitioned from quadrivalent to nonavalent HPV vaccines to broaden type coverage; program choices depend on availability, cost-effectiveness, and national policy.
• Ongoing surveillance: Safety monitoring continues; no new universal contraindications have been added, but local recommendations may be updated based on emerging evidence.

• Temperature: Store refrigerated at 2°C to 8°C. Do not freeze.
• Light & packaging: Keep in original packaging to protect from light.
• Handling precautions: Inspect before use; do not use if frozen, discolored, or containing particulate matter inconsistent with product description. Use aseptic technique for withdrawal and administration.
• Transport & cold chain: Maintain cold chain during transport and storage. Adhere to manufacturer guidance for in-use stability and discard times for opened vials if applicable.