Can Vaxelis Be Started at Age 2 Years?
No, Vaxelis should not be initiated in a 2-year-old child. The vaccine is licensed only for children aged 6 weeks through 4 years (prior to the 5th birthday), but it is specifically indicated for use as a primary infant vaccination series at ages 2,4, and 6 months—not for initiation at 2 years of age. 1
Licensing and Age Restrictions
Vaxelis is approved for use from 6 weeks through 4 years of age (up to the day before the 5th birthday), with a maximum age for any dose being 4 years and 364 days. 2, 1
However, the vaccine is only indicated for the primary vaccination series in infants at ages 2,4, and 6 months. 2, 1 This is a critical distinction—licensure covers an age range, but the indication specifies when the vaccine should actually be used.
The minimum age for the first dose is 6 weeks, with specific minimum intervals between doses (4 weeks between doses 1 and 2, and between doses 2 and 3). 2
Why Not Start at Age 2?
Vaxelis is designed as a primary infant series vaccine, not a catch-up vaccine for older children. While the CDC guidance states that "DTaP-IPV-Hib-HepB can be used for children aged <5 years requiring a catch-up schedule," 2 this refers to children who started their vaccination series late but are still within the infant/early toddler period—not children who are already 2 years old and completely unvaccinated.
At age 2 years, most children would have already completed or be well past the recommended timing for the primary series (2,4,6 months) and the Hib booster (12-15 months). 2
Vaxelis should not be used for booster doses. The vaccine is not indicated for the 4th or 5th doses of DTaP, the 4th dose of IPV, or the Hib booster dose at 12-15 months. 2
Appropriate Catch-Up Vaccination at Age 2
For a 2-year-old requiring catch-up vaccination:
Use age-appropriate individual component vaccines or other licensed combination vaccines that are indicated for catch-up schedules in this age group, following the CDC's catch-up immunization schedule. 2
Minimum interval requirements must be maintained when administering catch-up doses, as outlined in the General Best Practices Guidelines. 2
For Hib specifically, catch-up vaccination may not even be necessary at age 2 if the child is not at high risk, as the risk of invasive Hib disease decreases significantly after 5 years of age. 3
Clinical Caveat
If Vaxelis is inadvertently administered to a child outside the recommended age range (e.g., as a booster dose or in an older child), the dose does not need to be repeated if proper spacing of previous doses was maintained. 2 However, this does not mean the vaccine should be intentionally used in these situations.