ABSTRACT
Hexavalent vaccines containing diphtheria, tetanus, pertussis, Haemophilus influenzae type b, poliomyelitis, and hepatitis B virusantigens have the potential to be used for the primary series in India (6, 10, 14 weeks of age) and the toddler booster dose. Threehexavalent vaccines are available in India: DTwP-Hib/HepB-IPV (wP-hexa), DTaP-IPV-HB-PRP~T(2aP-hexa), and DTaP-HBV-IPV/Hib(3aP-hexa). In the three published phase-3 Indian studies, pertussis ‘vaccine response’ rates 1 month after a 6-10-14-week primaryseries were 68.4-75.7% for wP-hexa, 93.8-99.3% for 2aP-hexa, and 97.0-100% for 3aP-hexa; seroprotection rates for the other fiveantigens were 88.2-100%, 49.6-100%, and 98.6-100%, respectively. Studies outside India show: good immunogenicity/safety afterboosting dosing; immune persistence to age 4.5 years (2aP-hexa), 7-9 years (3aP-hexa) (all antigens), and 9-10 and 14-15 years,respectively (hepatitis B); and successful co-administration with other vaccines. Hexavalent vaccines could reduce the number ofinjections, simplify vaccination schedules, and improve compliance.