What is the recommended dosing schedule, administration route, contraindications, and catch‑up protocol for Vaxelis (pentavalent diphtheria‑tetanus‑acellular pertussis‑inactivated poliovirus‑Haemophilus influenzae type b‑hepatitis B) vaccine in a healthy infant older than six weeks?

Vaxelis Vaccine: Dosing, Administration, and Clinical Guidance

Direct Recommendation

Vaxelis should be administered as a 3-dose intramuscular series at 2,4, and 6 months of age in healthy infants, with a mandatory separate monovalent hepatitis B vaccine given at birth, and cannot be used for booster doses or in children 5 years or older. 1, 2

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Standard Dosing Schedule

Primary Series:

• Three doses administered at exactly 2,4, and 6 months of age as recommended by the CDC and FDA 1, 2
• Minimum age for first dose: 6 weeks 1, 3, 2
• Minimum interval between doses 1 and 2: 4 weeks 1
• Minimum interval between doses 2 and 3: 4 weeks 1
• Minimum age for dose 3: 24 weeks (approximately 6 months) 1

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Administration Route

• Intramuscular (IM) injection only 2
• Available as single-dose vials (0.5 mL) or prefilled syringes (0.5 mL) 2
• Can be coadministered with other routine childhood vaccines at the same visit 1, 4

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Critical Hepatitis B Birth Dose Requirement

Vaxelis is NOT licensed for the birth dose of hepatitis B vaccine 1, 2

• All infants must receive a separate monovalent hepatitis B vaccine at birth before starting the Vaxelis series 1
• For infants born to HBsAg-negative mothers: monovalent HepB at birth, then Vaxelis at 2,4, and 6 months 1
• For infants born to HBsAg-positive or unknown status mothers: monovalent HepB plus HBIG within 12 hours of birth, then Vaxelis at 2,4, and 6 months 1

Common Pitfall: If the third Vaxelis dose is inadvertently given before 24 weeks of age, an additional dose of hepatitis B vaccine must be administered at age ≥24 weeks to complete the hepatitis B series 1

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Absolute Contraindications

Your child should NOT receive Vaxelis if: 2

• Allergic to any vaccine ingredients (including aluminum salts, polysorbate 80, glutaraldehyde, formaldehyde, bovine serum albumin, neomycin, streptomycin, polymyxin B, ammonium thiocyanate, or yeast protein) 2
• Previous allergic reaction to any prior diphtheria, tetanus, pertussis, polio, Hib, or hepatitis B vaccine 2
• Serious reaction affecting the brain and nervous system after a previous whooping cough vaccine 2
• Progressive neurological disorder 2

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Precautions

Inform the healthcare provider if the child: 2

• Had problems with previous vaccines for these diseases 2
• Is taking steroids, receiving cancer treatment, or has immunocompromising conditions 2

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Age Limitations and Booster Dose Restrictions

Vaxelis is ONLY licensed for children aged 6 weeks through 4 years (up to 4 years, 364 days) 5, 2

• Cannot be administered on or after the fifth birthday 5
• Vaxelis should NOT be used for booster doses 1

Required separate vaccines for booster doses: 1

• DTaP vaccine for the fourth dose at 15-18 months 1
• Hib conjugate vaccine for the booster at 12-15 months 1
• IPV vaccine for the fourth dose at 4-6 years 1

The age restriction exists because the Hib component is not indicated beyond age 4 years in healthy children 5

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Catch-Up Protocol for Missed Doses

• If a dose is missed, the healthcare provider will suggest a catch-up schedule 2
• Maintain minimum intervals: 4 weeks between doses 1-2 and doses 2-3 1
• Ensure dose 3 is given at ≥24 weeks of age to meet hepatitis B requirements 1
• If Vaxelis is inadvertently given after age 5 years, it counts as a valid dose and does not need repeating 5

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Special Population: American Indian/Alaska Native Infants

As of 2024, Vaxelis is now included in the preferential recommendation for AI/AN infants 6

• Either monovalent PRP-OMP (2-dose series at 2 and 4 months) OR Vaxelis (3-dose series at 2,4, and 6 months) is preferred for AI/AN infants due to the PRP-OMP Hib component providing substantial protection after the first dose 6
• This updates the previous guidance that had limited data on antibody response in this population 1

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Common Side Effects

Expected reactions include: 2

• Pain, redness, or swelling at injection site 2
• Fever (≥100.4°F) 2
• Increased crying, fussiness, or sleepiness 2
• Decreased appetite 2
• Vomiting 2

Clinical studies demonstrate Vaxelis is generally well tolerated with a tolerability profile similar to comparator vaccines 4

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Immunogenicity

• Vaxelis demonstrates high immunogenicity for all component antigens when administered at 2,4, and 6 months 4
• Seroprotection rates meet predefined acceptability criteria and are noninferior to comparator vaccines (Infanrix hexa or Pentacel plus Recombivax HB) 4
• Immune responses in preterm infants are generally similar to the overall population 4

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Reporting Adverse Events

• Report side effects to VAERS at 1-800-822-7967 or http://vaers.hhs.gov 2
• Contact Sanofi Pasteur Inc. at 1-800-822-2463 2