Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a vaccine cannot be directly compared to rates in the clinical trials of another vaccine and may not reflect the rates observed in practice.
A total of 23,849 doses of PEDIARIX have been administered to 8,088 infants who received 1 or more doses as part of the 3-dose series during 14 clinical studies. Common adverse reactions that occurred in ≥25% of subjects following any dose of PEDIARIX included local injection site reactions (pain, redness, and swelling), fever, drowsiness, irritability/fussiness, and loss of appetite. In comparative studies (including the German and U.S. studies described below), administration of PEDIARIX was associated with higher rates of fever relative to separately administered vaccines [see Warnings and Precautions (5.1)]. The prevalence of fever was highest on the day of vaccination and the day following vaccination. More than 96% of episodes of fever resolved within the 4-day period following vaccination (i.e., the period including the day of vaccination and the next 3 days).
In the largest of the 14 studies conducted in Germany, safety data were available for 4,666 infants who received PEDIARIX administered concomitantly at separate sites with 1 of 4 Haemophilus influenzae type b (Hib) conjugate vaccines (GlaxoSmithKline [licensed in the United States only for booster immunization], Wyeth Pharmaceuticals Inc. [no longer licensed in the United States], Sanofi Pasteur SA [U.S.-licensed], or Merck & Co, Inc. [U.S.-licensed]) at 3, 4, and 5 months of age and for 768 infants in the control group that received separate U.S.-licensed vaccines (INFANRIX, Hib conjugate vaccine [Sanofi Pasteur SA], and oral poliovirus vaccine [OPV] [Wyeth Pharmaceuticals, Inc.; no longer licensed in the United States]). In this study, information on adverse events that occurred within 30 days following vaccination was collected. More than 95% of study participants were White.
In a U.S. study, the safety of PEDIARIX administered to 673 infants was compared with the safety of separately administered INFANRIX, ENGERIX-B [Hepatitis B Vaccine (Recombinant)], and IPV (Sanofi Pasteur SA) in 335 infants. In both groups, infants received Hib conjugate vaccine (Wyeth Pharmaceuticals Inc.; no longer licensed in the United States) and 7-valent pneumococcal conjugate vaccine (Wyeth Pharmaceuticals Inc.) concomitantly at separate sites. All vaccines were administered at 2, 4, and 6 months of age. Data on solicited local reactions and general adverse reactions were collected by parents using standardized diary cards for 4 consecutive days following each vaccine dose (i.e., day of vaccination and the next 3 days). Telephone follow-up was conducted 1 month and 6 months after the third vaccination to inquire about serious adverse events. At the 6-month follow-up, information also was collected on new onset of chronic illnesses. A total of 638 subjects who received PEDIARIX and 313 subjects who received INFANRIX, ENGERIX-B, and IPV completed the 6-month follow-up. Among subjects in both study groups combined, 69% were White, 18% were Hispanic, 7% were Black, 3% were Asian, and 3% were of other racial/ethnic groups.
Solicited Adverse Reactions
Data on solicited local reactions and general adverse reactions from the U.S. safety study are presented in Table 1. This study was powered to evaluate fever >101.3°F following Dose 1. The rate of fever ≥100.4°F following each dose was significantly higher in the group that received PEDIARIX compared with separately administered vaccines. Other statistically significant differences between groups in rates of fever, as well as other solicited adverse reactions, are noted in Table 1. Medical attention (a visit to or from medical personnel) for fever within 4 days following vaccination was sought in the group who received PEDIARIX for 8 infants after the first dose (1.2%), 1 infant following the second dose (0.2%), and 5 infants following the third dose (0.8%) (Table 1). Following Dose 2, medical attention for fever was sought for 2 infants (0.6%) who received separately administered vaccines (Table 1). Among infants who had a medical visit for fever within 4 days following vaccination, 9 of 14 who received PEDIARIX and 1 of 2 who received separately administered vaccines, had 1 or more diagnostic studies performed to evaluate the cause of fever.
Table 1. Percentage of Infants with Solicited Local and General Adverse Reactions within 4 Days of Vaccinationa at 2, 4, and 6 Months of Age with PEDIARIX Administered Concomitantly with Hib Conjugate Vaccine and 7-Valent Pneumococcal Conjugate Vaccine (PCV7) or with Separate Concomitant Administration of INFANRIX, ENGERIX-B, IPV, Hib Conjugate Vaccine, and PCV7 (Modified Intent-to-Treat Cohort)Hib conjugate vaccine (Wyeth Pharmaceuticals Inc.; no longer licensed in the United States); PCV7 (Wyeth Pharmaceuticals Inc.); IPV (Sanofi Pasteur SA). Modified intent-to-treat cohort = All vaccinated subjects for whom safety data were available. n = Number of infants for whom at least 1 symptom sheet was completed; for fever, numbers exclude missing temperature recordings or tympanic measurements. M.A. = Medically attended (a visit to or from medical personnel). Grade 2 defined as sufficiently discomforting to interfere with daily activities. Grade 3 defined as preventing normal daily activities. a Within 4 days of vaccination defined as day of vaccination and the next 3 days. b Local reactions at the injection site for PEDIARIX or INFANRIX. c Rate significantly higher in the group that received PEDIARIX compared with separately administered vaccines (P value <0.05 [2-sided Fisher Exact test] or the 95% CI on the difference between groups [Separate minus PEDIARIX] does not include 0). d Axillary temperatures increased by 1°C and oral temperatures increased by 0.5°C to derive equivalent rectal temperature. |
Adverse Reaction | PEDIARIX, Hib Vaccine, & PCV7 | INFANRIX, ENGERIX-B, IPV, Hib Vaccine, & PCV7 |
Dose 1 | Dose 2 | Dose 3 | Dose 1 | Dose 2 | Dose 3 |
Localb | | | | | | |
n | 671 | 653 | 648 | 335 | 323 | 315 |
Pain, any | 36 | 36 | 31 | 32 | 30 | 30 |
Pain, Grade 2 or 3 | 12 | 11 | 11 | 9 | 9 | 9 |
Pain, Grade 3 | 2 | 3 | 2 | 3 | 2 | 1 |
Redness, any | 25c | 37 | 40 | 18 | 33 | 39 |
Redness, >5 mm | 6c | 10c | 13c | 2 | 6 | 7 |
Redness, >20 mm | 1 | 1c | 3 | 0 | 0 | 2 |
Swelling, any | 17c | 27c | 29 | 10 | 20 | 25 |
Swelling, >5 mm | 6c | 10c | 9c | 2 | 5 | 4 |
Swelling, >20 mm | 2 | 3c | 3 | 1 | 0 | 1 |
General | | | | | | |
n | 667 | 644 | 645 | 333 | 321 | 311 |
Feverd, ≥100.4°F | 28c | 39c | 34c | 20 | 30 | 24 |
Feverd, >101.3°F | 7 | 14c | 9 | 5 | 10 | 6 |
Feverd, >102.2°F | 2c | 4 | 3 | 0 | 3 | 2 |
Feverd, >103.1°F | 1 | 1 | 1 | 0 | 0 | 0 |
Feverd, M.A. | 1c | 0 | 1 | 0 | 1 | 0 |
n | 671 | 653 | 648 | 335 | 323 | 315 |
Drowsiness, any | 57 | 52 | 41 | 54 | 48 | 38 |
Drowsiness, Grade 2 or 3 | 16 | 14 | 11 | 18 | 12 | 11 |
Drowsiness, Grade 3 | 3 | 1 | 1 | 4 | 1 | 2 |
Irritability/Fussiness, any | 61 | 65 | 61 | 62 | 62 | 57 |
Irritability/Fussiness, Grade 2 or 3 | 20 | 28c | 25c | 19 | 21 | 19 |
Irritability/Fussiness, Grade 3 | 3 | 4 | 4 | 4 | 3 | 3 |
Loss of appetite, any | 30 | 31 | 26 | 28 | 27 | 24 |
Loss of appetite, Grade 2 or 3 | 7 | 8c | 6 | 5 | 3 | 5 |
Loss of appetite, Grade 3 | 1 | 0 | 0 | 1 | 0 | 0 |
Serious Adverse Events
Within 30 days following any dose of vaccine in the U.S. safety study in which all subjects received concomitant Hib and pneumococcal conjugate vaccines, 7 serious adverse events were reported in 7 subjects (1% [7/673]) who received PEDIARIX (1 case each of pyrexia, gastroenteritis, and culture-negative clinical sepsis and 4 cases of bronchiolitis) and 5 serious adverse events were reported in 4 subjects (1% [4/335]) who received INFANRIX, ENGERIX-B, and IPV (uteropelvic junction obstruction and testicular atrophy in 1 subject and 3 cases of bronchiolitis).
Deaths
In 14 clinical trials, 5 deaths were reported among 8,088 (0.06%) recipients of PEDIARIX and 1 death was reported among 2,287 (0.04%) recipients of comparator vaccines. Causes of death in the group that received PEDIARIX included 2 cases of Sudden Infant Death Syndrome (SIDS) and 1 case of each of the following: convulsive disorder, congenital immunodeficiency with sepsis, and neuroblastoma. One case of SIDS was reported in the comparator group. The rate of SIDS among all recipients of PEDIARIX across the 14 trials was 0.25/1,000. The rate of SIDS observed for recipients of PEDIARIX in the German safety study was 0.2/1,000 infants (reported rate of SIDS in Germany in the latter part of the 1990s was 0.7/1,000 newborns). The reported rate of SIDS in the United States from 1990 to 1994 was 1.2/1,000 live births. By chance alone, some cases of SIDS can be expected to follow receipt of pertussis-containing vaccines.
Onset of Chronic Illnesses
In the U.S. safety study in which all subjects received concomitant Hib and pneumococcal conjugate vaccines, 21 subjects (3%) who received PEDIARIX and 14 subjects (4%) who received INFANRIX, ENGERIX-B, and IPV reported new onset of a chronic illness during the period from 1 to 6 months following the last dose of study vaccines. Among the chronic illnesses reported in the subjects who received PEDIARIX, there were 4 cases of asthma and 1 case each of diabetes mellitus and chronic neutropenia. There were 4 cases of asthma in subjects who received INFANRIX, ENGERIX-B, and IPV.
Seizures
In the German safety study over the entire study period, 6 subjects in the group that received PEDIARIX (n = 4,666) reported seizures. Two of these subjects had a febrile seizure, 1 of whom also developed afebrile seizures. The remaining 4 subjects had afebrile seizures, including 2 with infantile spasms. Two subjects reported seizures within 7 days following vaccination (1 subject had both febrile and afebrile seizures, and 1 subject had afebrile seizures), corresponding to a rate of 0.22 seizures per 1,000 doses (febrile seizures 0.07 per 1,000 doses, afebrile seizures 0.14 per 1,000 doses). No subject who received concomitant INFANRIX, Hib vaccine, and OPV (n = 768) reported seizures. In a separate German study that evaluated the safety of INFANRIX in 22,505 infants who received 66,867 doses of INFANRIX administered as a 3-dose primary series, the rate of seizures within 7 days of vaccination with INFANRIX was 0.13 per 1,000 doses (febrile seizures 0.0 per 1,000 doses, afebrile seizures 0.13 per 1,000 doses).
Over the entire study period in the U.S. safety study in which all subjects received concomitant Hib and pneumococcal conjugate vaccines, 4 subjects in the group that received PEDIARIX (n = 673) reported seizures. Three of these subjects had a febrile seizure and 1 had an afebrile seizure. Over the entire study period, 2 subjects in the group that received INFANRIX, ENGERIX-B, and IPV (n = 335) reported febrile seizures. There were no afebrile seizures in this group. No subject in either study group had seizures within 7 days following vaccination.
Other Neurological Events of Interest
No cases of hypotonic-hyporesponsiveness or encephalopathy were reported in either the German or U.S. safety studies.
Safety of PEDIARIX after a Previous Dose of Hepatitis B Vaccine
Limited data are available on the safety of administering PEDIARIX after a previous dose of hepatitis B vaccine. In 2 separate studies, 160 Moldovan infants and 96 U.S. infants, respectively, received 3 doses of PEDIARIX following 1 previous dose of hepatitis B vaccine. Neither study was designed to detect significant differences in rates of adverse events associated with PEDIARIX administered after a previous dose of hepatitis B vaccine compared with PEDIARIX administered without a previous dose of hepatitis B vaccine.