FDA OKs Pediatric Hexavalent Combination Vaccine

Officials with the US FDA have approved a vaccine for use in children younger than age 5 that is indicated for immunization to prevent diphtheria, tetanus, pertussis, poliomyelitis, hepatitis B, and invasive disease due to Haemophilus influenzae type b (Vaxelis™).

Developed as part of a joint partnership between Sanofi and Merck, the companies are working to maximize production of the vaccine to allow for a sustainable supply to meet anticipated demand, but commercial supply is not expected until 2020. The vaccine is approved for use as a 3-dose series, which consists of a 0.5 mL intramuscular injection, administered at 2, 4, and 6 months of age. This vaccine does not constitute a primary immunization series against pertussis.

Contraindicated in children with a history of anaphylaxis to any ingredient in the vaccine, health care officials are also advised not to administer Vaxelis to anyone with a history of encephalopathy, within 7 days of a pertussis-containing vaccine, that is not attributable to another identifiable cause. The vaccine is also not to be administered to anyone with a history of progressive neurologic disorder until a treatment regimen has been established and the condition has stabilized.

A press release from Sanofi advises health care officials to "carefully consider benefits and risks before administering Vaxelis to persons with a history of:

• fever of ≥105°F,
• hypotonic-hyporesponsive episode (HHE) or persistent, inconsolable crying lasting ≥3 hours within 48 hours after a previous pertussis-containing vaccine,
• seizures within 3 days after a previous pertussis-containing vaccine.

The adverse reactions following any dose were irritability (≥55%), crying (≥45%), injection site pain (≥44%), somnolence (≥40%), injection site erythema (≥25%), decreased appetite (≥23%), fever ≥38.0°C (≥19%), injection site swelling (≥18%), and vomiting (≥9%).