Pur po se : To reduce the number of injections necessary to vaccinate young infants, various
combined vaccines have been developed. The ComvaxTM manufactured by Merck & Co. is a
combination of Hepatitis B and PRP-OMP conjugate Haemophilus influenzae Type b vaccine.
The purpose of this study is to evaluate the immunogenicity and safety of ComvaxTM in
Korean infants.
Methods : The infants who were vaccinated at 0 months of age with Hepatitis B
vaccine, were recruited for this study after parental informed consent was obtained. The
subjects were vaccinated with ComvaxTM at 2 and 4 months of age. At each visit, infants
were also immunized with DTaP, inactivated poliovirus vaccine, and pneumococcal vaccine
when indicated. The serum anti-PRP and anti-HBs were measured at 2 months after the 1st
dose(4 months age), and the 2nd dose(6 months age) by the ELISA and chemiluminescent
microparticle immunoassay method, respectively. The local and systemic adverse reactions of
vaccination were monitored for 3 consecutive days after each immunization.
Results : Among sixty-five healthy infants(35 male infants) enrolled in this study; fifty
eight(32 male infants) completed the scheduled immunizations. The geometric mean titers (GMTs) of anti-PRP at 2 months after the 1st dose and the 2nd dose were 1.96 μg/mL
(95% CI; 1.38∼2.78) and 10.02 μg/mL (95% CI; 7.04∼14.26), respectively. Anti-PRP ≥1.0
μg/mL, was obtained in 63.2%(95% CI; 53.75∼72.65) after 1 dose, and 96.6%(95% CI;
93.05∼100) after 2 doses. The GMTs of anti-HBs were 38.32 mIU/mL(95% CI; 22.42∼
65.51), and 101.17 mIU/mL(95% CI; 65.94∼155.25) at 2 month after the 1st dose and 2nd
dose of ComvaxTM, respectively. Anti-HBs ≥10 mIU/mL was observed in 73.7%(95% CI;
65.07∼82.33) after 1 dose and 94.8%(95% CI; 90.45∼99.15) after 2 doses. Most of the
adverse reactions after vaccination were mild. Irritability, the most common systemic reaction,
was observed in 24.8%, followed by drowsiness(19.2%), poor feeding(19.2%) and fever(7.2%).
Among the local reactions tenderness was observed in 25.6%, redness(≥ 5 mm) in 19.2%
and swelling(≥5 mm) in 4.8%.
Co nclusio n : The ComvaxTM vaccine was highly immunogenic for PRP and safe in
Korean infants. Although the hepatitis B vaccine component was administered at 0, 2, 4
months, this study showed good immunogenicity against HBsAg.
Pur po se : To reduce the number of injections necessary to vaccinate young infants, various
combined vaccines have been developed. The ComvaxTM manufactured by Merck & Co. is a
combination of Hepatitis B and PRP-OMP conjugate Haemophilus influenzae Type b vaccine.
The purpose of this study is to evaluate the immunogenicity and safety of ComvaxTM in
Korean infants.
Methods : The infants who were vaccinated at 0 months of age with Hepatitis B
vaccine, were recruited for this study after parental informed consent was obtained. The
subjects were vaccinated with ComvaxTM at 2 and 4 months of age. At each visit, infants
were also immunized with DTaP, inactivated poliovirus vaccine, and pneumococcal vaccine
when indicated. The serum anti-PRP and anti-HBs were measured at 2 months after the 1st
dose(4 months age), and the 2nd dose(6 months age) by the ELISA and chemiluminescent
microparticle immunoassay method, respectively. The local and systemic adverse reactions of
vaccination were monitored for 3 consecutive days after each immunization.
Results : Among sixty-five healthy infants(35 male infants) enrolled in this study; fifty
eight(32 male infants) completed the scheduled immunizations. The geometric mean titers (GMTs) of anti-PRP at 2 months after the 1st dose and the 2nd dose were 1.96 μg/mL
(95% CI; 1.38∼2.78) and 10.02 μg/mL (95% CI; 7.04∼14.26), respectively. Anti-PRP ≥1.0
μg/mL, was obtained in 63.2%(95% CI; 53.75∼72.65) after 1 dose, and 96.6%(95% CI;
93.05∼100) after 2 doses. The GMTs of anti-HBs were 38.32 mIU/mL(95% CI; 22.42∼
65.51), and 101.17 mIU/mL(95% CI; 65.94∼155.25) at 2 month after the 1st dose and 2nd
dose of ComvaxTM, respectively. Anti-HBs ≥10 mIU/mL was observed in 73.7%(95% CI;
65.07∼82.33) after 1 dose and 94.8%(95% CI; 90.45∼99.15) after 2 doses. Most of the
adverse reactions after vaccination were mild. Irritability, the most common systemic reaction,
was observed in 24.8%, followed by drowsiness(19.2%), poor feeding(19.2%) and fever(7.2%).
Among the local reactions tenderness was observed in 25.6%, redness(≥ 5 mm) in 19.2%
and swelling(≥5 mm) in 4.8%.
Co nclusio n : The ComvaxTM vaccine was highly immunogenic for PRP and safe in
Korean infants. Although the hepatitis B vaccine component was administered at 0, 2, 4
months, this study showed good immunogenicity against HBsAg.