Hexaxim

Approved Indications:

• Primary immunization of infants from 6 weeks of age against:
• Diphtheria (Corynebacterium diphtheriae)
• Tetanus (Clostridium tetani)
• Pertussis (Whooping cough; Bordetella pertussis)
• Hepatitis B (HBV)
• Poliomyelitis (Types 1, 2, and 3; inactivated poliovirus)
• Haemophilus influenzae type b (Hib) – causing meningitis, epiglottitis, pneumonia, and bacteremia
• Booster doses in line with national immunization programs

Clinically Accepted Use:

• Catch-up immunization for incompletely immunized children under age 5

Route of Administration: Intramuscular (IM) injection, preferably in the anterolateral thigh (vastus lateralis) in infants

Dosage:

• Each 0.5 mL dose typically contains:
• Diphtheria toxoid (≥30 IU)
• Tetanus toxoid (≥40 IU)
• Acellular pertussis antigens (e.g., PT, FHA)
• Recombinant Hepatitis B surface antigen (≥10 µg)
• Inactivated poliovirus types 1, 2, 3
• Conjugated Hib polysaccharide antigen (usually with tetanus toxoid as carrier)

Routine Immunization Schedule (Infants):

• 3-dose series:
• First dose: at 6 weeks of age
• Second dose: at 10 weeks
• Third dose: at 14 weeks

Booster Doses:

• Depending on national guidelines (e.g., at 12–18 months of age)
• Some programs include additional boosters with separate DTP, IPV, or Hib components

Catch-up Vaccination:

• Can be used in infants and toddlers under 5 years based on age-appropriate schedules
• Number of doses and intervals depend on prior immunization history

Special Populations:

• Preterm infants: Same schedule as full-term infants; monitor for apnea
• HIV-infected infants: Safe and recommended

This hexavalent vaccine stimulates the immune system to develop both humoral and cellular immunity against six pathogens. The diphtheria and tetanus components are toxoids, which induce neutralizing antibodies against bacterial exotoxins. Acellular pertussis antigens stimulate immune responses that prevent colonization and toxin-mediated pathology. Hepatitis B antigen (HBsAg) elicits protective antibodies that prevent viral entry into hepatocytes. Inactivated poliovirus induces neutralizing antibodies preventing viral replication and neuroinvasion. The Hib component, a conjugated polysaccharide-protein complex, promotes T-cell–dependent immunity and long-lasting memory responses, particularly effective in infants.

As a vaccine, it does not follow standard pharmacokinetic parameters (no systemic absorption, metabolism, or excretion as with drugs). However:

• Onset of Immunity:
• Detectable antibody responses occur after 1–2 doses
• Protective levels achieved after 3-dose primary series
• Duration of Immunity:
• Varies by component
• Generally requires booster doses to maintain protection into childhood
• No systemic circulation of the vaccine antigens; all immune responses occur locally and systemically via antigen-presenting cells

• Pregnancy:
• Not indicated for use in pregnant individuals as it is a pediatric vaccine
• Individual components like Tdap may be used in pregnancy for maternal immunization
• Lactation:
• Not applicable (pediatric use only)
• No risk to breastfeeding mothers or breastfed infants when the child receives this vaccine

• Class: Inactivated combination vaccine
• Subtype: Hexavalent pediatric vaccine (DTPa-HBV-IPV/Hib)

• Known hypersensitivity to any vaccine component (e.g., neomycin, polymyxin B, formaldehyde, or latex if present)
• Severe allergic reaction (e.g., anaphylaxis) after a previous dose of this vaccine or a vaccine component
• History of encephalopathy within 7 days following a previous pertussis-containing vaccine
• Progressive neurological disorders (e.g., uncontrolled epilepsy) – vaccination should be deferred

• Premature infants: Risk of apnea; monitor after vaccination, especially if ≤28 weeks gestation
• Febrile illness: Defer vaccination during acute moderate or severe illness
• History of seizures: Use with caution; antipyretics may be given to reduce risk of febrile seizures
• GBS or brachial neuritis: Evaluate risk-benefit if associated with prior tetanus vaccination
• Syncope (fainting): May occur in older children; monitor post-vaccination

Common (≥10%):

• Local: Pain, redness, swelling at injection site
• Systemic: Fever, irritability, drowsiness, loss of appetite, vomiting

Less Common (1–10%):

• Diarrhea
• Injection site induration
• Persistent crying >3 hours (especially after pertussis component)

Serious/Rare (<0.1%):

• Febrile seizures
• Anaphylaxis
• Hypotonic-hyporesponsive episodes (HHE)
• Guillain-Barré syndrome (very rare)

Timing of onset: Most mild reactions occur within 48 hours; severe reactions within 7 days (especially with pertussis antigen)

• Live vaccines: May be administered simultaneously at different injection sites with separate syringes
• Immunosuppressants (e.g., corticosteroids, chemotherapy): May reduce immunologic response — postpone if possible
• No known interactions with food or alcohol (not applicable for pediatric use)
• No cytochrome P450 involvement, as it is a biologic vaccine

• WHO & National Guidelines: Support use of combination hexavalent vaccines to reduce injection burden and improve compliance
• Global shift from DTwP to DTaP-based hexavalent vaccines in many countries for improved safety and tolerability
• WHO prequalified hexavalent vaccines now being implemented in low- and middle-income countries under global immunization programs
• GAVI-supported countries are increasingly adopting these vaccines to align with global eradication goals (e.g., polio)

• Temperature: Store at 2°C to 8°C (36°F to 46°F); do not freeze
• Light Protection: Protect from light; store in original packaging
• Handling: Shake well before use; do not use if the product appears discolored or contains particles
• Discard if frozen or after expiration date