Meningococcal Polysaccharide Diphtheria Toxoid Conjugate Vaccine

Approved Indications:

• Prevention of invasive meningococcal disease caused by Neisseria meningitidis serogroups A, C, W, and Y, in individuals aged 9 months through 55 years, depending on the specific vaccine product.
• Routine vaccination of adolescents at 11–12 years, with a booster dose at age 16.
• Catch-up vaccination for unvaccinated adolescents up to age 21.
• High-risk groups, including:
• Individuals with anatomical or functional asplenia (e.g., sickle cell disease)
• Individuals with persistent complement component deficiencies
• HIV-infected individuals
• First-year college students living in dormitories
• Military recruits
• Laboratory personnel routinely exposed to N. meningitidis

Clinically Accepted Off-label Uses:

• Travelers to areas with high endemicity or outbreaks of meningococcal disease (e.g., sub-Saharan Africa, Hajj pilgrimage)
• Outbreak control in institutional or community settings
• Adults >55 years when polysaccharide vaccine is not available or contraindicated

Route: Intramuscular (IM), preferably into the deltoid muscle
Dosage Form: Suspension for injection in single-dose vials or prefilled syringes (0.5 mL)

Routine Immunization Schedule:

• Children 9–23 months:
• 2-dose primary series (0.5 mL each) at least 3 months apart (e.g., 9 and 12 months)
• Children 2–10 years:
• Single dose (0.5 mL) for healthy children
• 2-dose primary series (2 months apart) for high-risk groups
• Adolescents 11–18 years:
• First dose at 11–12 years
• Booster dose at 16 years
• Adults 19–55 years:
• Single dose (0.5 mL) if indicated
• Booster every 5 years for individuals at continued risk

Special Populations:

• Asplenia, complement deficiencies, or HIV:
• 2 doses (0.5 mL each), 8 weeks apart
• Booster every 5 years if risk persists

Co-administration:

• May be given concurrently with other routine vaccines at separate injection sites using different syringes

This conjugate vaccine contains purified capsular polysaccharides from Neisseria meningitidis serogroups A, C, W, and Y, each chemically linked (conjugated) to a diphtheria toxoid protein. The conjugation converts the T-cell–independent polysaccharide antigens into T-cell–dependent antigens, enhancing immune recognition and promoting the development of immunologic memory. This results in a strong, long-lasting antibody response capable of neutralizing meningococcal bacteria and preventing invasive disease. It also reduces nasopharyngeal carriage and transmission within populations.

As with all vaccines, traditional pharmacokinetics (ADME) does not apply. However:

• Onset of protection: Protective antibody response develops within 7–10 days of vaccination
• Duration of protection: Antibody titers remain protective for approximately 3–5 years; longer in older children and adults
• Booster response: Demonstrates strong anamnestic immune response due to T-cell–dependent immunity

Pregnancy:

• Former FDA Category: B (varies by manufacturer)
• Current recommendation: No evidence of fetal harm from available human data. Use if the potential benefit outweighs the risk, particularly in high-risk situations (e.g., outbreaks, travel).

Lactation:

• No known risk; not excreted in breast milk
• Safe for breastfeeding women

Caution: Data in pregnant or breastfeeding women are limited; decision should be individualized.

• Primary Class: Vaccine
• Subclass: Conjugated Bacterial Vaccine
• Target Antigens: Capsular polysaccharides from N. meningitidis serogroups A, C, W, Y, conjugated to diphtheria toxoid

• Known hypersensitivity to any component of the vaccine, including diphtheria toxoid
• History of severe allergic reaction (e.g., anaphylaxis) after a previous dose of meningococcal vaccine
• Acute, moderate, or severe febrile illness (postpone vaccination until recovery)

• Guillain-Barré Syndrome (GBS): Rare post-marketing reports; use with caution in patients with prior history of GBS
• Immunosuppression: May reduce vaccine response; revaccination or additional doses may be required
• Syncope: Common among adolescents; observe for 15 minutes post-vaccination to prevent injury
• Latex Allergy: Check product-specific labeling for latex content in vial stoppers or syringes
• Fever or febrile seizures: Monitor infants closely post-vaccination

Very Common (≥10%):

• Local: Pain, redness, and swelling at injection site
• Systemic: Irritability, sleepiness, and decreased appetite in infants

Common (1–10%):

• Fever
• Headache
• Fatigue
• Nausea
• Diarrhea
• Muscle aches

Rare/Serious:

• Hypersensitivity reactions (e.g., rash, anaphylaxis)
• Seizures (febrile, typically self-limiting)
• Guillain-Barré Syndrome (extremely rare)

Onset: Most side effects occur within 1–3 days after injection and are self-limiting

• Live vaccines: Can be administered simultaneously at different sites
• Immunosuppressants (e.g., corticosteroids, chemotherapy): May decrease vaccine efficacy
• No food or alcohol interactions reported

CYP450 Involvement: Not applicable

• CDC (ACIP): Continues to recommend the use of meningococcal conjugate vaccines for routine adolescent immunization and high-risk groups
• WHO: Encourages widespread use in regions with endemic or epidemic meningococcal disease
• Recent changes: Expanded indication for use starting at 9 months of age in high-risk children
• Ongoing recommendations: Booster doses every 5 years for individuals with persistent risk

• Temperature: Store at 2°C to 8°C (36°F to 46°F)
• Do not freeze: Freezing damages the vaccine and renders it ineffective
• Light sensitivity: Store in original packaging to protect from light
• Handling:
• Shake well before use (if suspension)
• Use immediately after opening or reconstitution (if applicable)
• Reconstitution: Required only for specific brands; follow manufacturer's instructions