Clinical Trial Details
— Status: Completed
Administrative data
NCT number |
NCT01953510 |
Other study ID # |
09/19 |
Secondary ID |
56679210PN-PD-DI |
Status |
Completed |
Phase |
Phase 2/Phase 3
|
First received |
|
Last updated |
|
Start date |
September 30, 2013 |
Est. completion date |
November 8, 2021 |
Study information
Verified date |
September 2022 |
Source |
Murdoch Childrens Research Institute |
Contact |
n/a |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
Pneumococcus is a group of bacteria that can cause pneumonia, meningitis and other diseases.
These bacteria normally live in the nose of humans and are spread from person to person by
touching or sneezing. There are vaccines available to protect against infection with these
bacteria, and pneumococcus is currently the leading vaccine-preventable cause of death in
young children. In countries where pneumococcal vaccine (PCV) has been introduced, there has
been a big impact on the amount of disease caused by these bacteria. However, many countries,
especially developing countries, are yet to introduce PCV as part of their routine
immunizations. Currently a total of four doses of PCV is recommended, and the main barrier to
vaccine introduction is cost. This study aims to identify a vaccination schedule to make PCV
more effective and affordable for Vietnam and other developing countries.
This study has two distinct purposes: 1) to compare different dosage schedules of PCV and 2)
to compare different PCV vaccines.
1. Schedules of Synflorix (PCV10) involving a three, two or one dose PCV primary series and
two booster options will be compared. Comparisons will be made firstly in terms of
measures of immunity to the vaccine, and secondly in terms of the effect of vaccination
on the carriage of bacteria in the nose.
2. The responses to PCV10 and Prevenar-13 (PCV13) will be compared, in the schedule most
likely to be considered for global use. Again, comparisons will be made in terms of
measures of immunity and effect on carriage in the nose.
Infants aged two months will be randomly assigned to one of six study groups and will provide
up to four blood samples for analysis of the measures of immunity and five nose swabs for
analysis of carriage of bacteria. Infants will be followed up 8-9 times until the age of 24
months. An additional control group will be recruited at 18 months of age and also followed
up until 24 months of age.
The results of this study will be used to facilitate decision making, at global and national
levels, regarding introduction of PCV.
Description:
Introduction
The overall purpose of this study is to investigate simplified childhood vaccination
schedules that are more appropriate for developing country use. This study is specifically
designed to address two independent questions within a single study:
1. What is the optimal schedule for provision of EPI vaccines with the incorporation of
PCV10? Schedules involving a three, two or one dose PCV10 primary series will be
evaluated, timed around options for simplification of the Expanded Programme of
Immunization (EPI) schedule for developing countries. A simplified schedule with the
pneumococcal booster dose brought forward closer to the peak incidence of disease is
likely both to increase compliance and vaccine effectiveness. A booster at nine months
of age coincides with the usual time for administration of measles vaccine, whereas a
booster at six months of age would provide earlier protection and may enable a further
abbreviated 1+1 pneumococcal vaccination schedule.
2. How do the responses to PCV vaccination with PCV10 or PCV13 compare? PCV10 and PCV13 are
the two PCVs available through the Advanced Market Commitment (AMC) mechanism, a
mechanism that provides funds for vaccine introduction into developing countries.
However, there have been no studies to date directly comparing these two vaccines.
Directly comparing these two vaccines will provide useful information to countries
considering introduction of PCV. There are important differences between these vaccines.
PCV10 includes ten pneumococcal serotypes and PCV13 includes thirteen. PCV10 uses a
non-typeable Haemophilus influenzae (NTHi) Protein D carrier, which may confer
protection against H. influenzae, and PCV13 uses a CRM197 carrier. It is of interest to
know whether these vaccines differ either in their immunogenicity or their impact on
nasopharyngeal (NP) carriage.
Design
Infants will be randomized to one of six study arms (A-F). All infant participants receive
four doses of Infanrix-hexa (DTaP-Hib-HBV-IPV) and at least two doses of PCV. The PCV
schedules to be evaluated are: a 3+1 PCV10 schedule at 2, 3, 4 and 9 months of age (Arm A); a
3+0 PCV10 schedule at 2, 3 and 4 months of age (Arm B); a 2+1 PCV10 schedule at 2, 4 and 9
months of age (Arm C); a 1+1 PCV10 schedule at 2 and 6 months of age (Arm D); a 2+1 PCV13
schedule at 2, 4 and 9 months of age (Arm E). Arm F, the control group, receives two doses of
PCV10 at 18 and 24 months of age. An additional control group (Arm G) will be recruited at 18
months of age and will receive Infanrix-hexa at 18 months of age and a single dose of PCV10
at 24 months of age. Reactogenicity will be assessed following all vaccination visits through
the use of diary cards.
Participants from arms A-E will provide six NP swabs for analysis of the NP carriage
outcomes, at 2, 6, 9, 12, 18 and 24 months of age; and will provide four blood samples over
the course of the trial for analysis of vaccine responses. Blood 1 will be taken four weeks
post-primary series; Blood 2 will be taken pre-booster (arms A, C, D and E) or at 9 months of
age (subset of arm B); and Blood 3 will be taken four weeks post-booster (arms A, C, D and E)
or at 10 months of age (arm B). An additional blood sample will be taken at: 18 months of age
for a subset of arms A, B, C, D and E; 2 months of age for a subset of arm A; 6 months of age
for a subset of arms B and C; 9 months of age for a subset of arm D; or 3 months of age for a
subset of arm E. Participants from the control arms will provide NP swabs at 2, 6, 9, 12, 18
and 24 months of age (arm F) or at 18 and 24 months of age (arm G), and will provide blood
samples at 18 (Blood 4), 19 (Blood X) and 24 (Blood Y) months of age.
Objectives
1. What is the optimal schedule for provision of EPI vaccines with the incorporation of
PCV10? The primary objective is to compare a 2+1 schedule at 2, 4 and 9 months of age
with a 3+1 schedule at 2, 3, 4 and 9 months of age, with a primary outcome of the
immunogenicity of PCV10, four weeks post-primary series (Arm C vs. Arm A+B). Secondary
objectives are to investigate an experimental 1+1 schedule at 2 and 6 months of age (Arm
D vs. Arm A+B and Arm D vs. Arm C), and to assess the impact of a booster dose on
carriage (Arm A vs. Arm F and Arm A vs. Arm B).
2. How do the responses to PCV vaccination with PCV10 or PCV13 compare? The primary
objective is to compare a PCV13 schedule at 2, 4 and 9 months of age with a PCV10
schedule at 2, 3, 4 and 9 months of age, with a primary outcome of the immunogenicity of
PCV, four weeks post-primary series (Arm E vs. Arm A+B). Secondary objectives are to
compare a PCV13 schedule at 2, 4 and 9 months of age with a PCV10 schedule at 2, 4 and 9
months of age (Arm E vs. Arm C), and to compare the responses to a single dose of PCV13
or PCV10 (Arm E vs. Arm D).
Other objectives are: to examine the decline in pneumococcal antibody levels over time (Arm
B); to describe the serotype profile of transferred maternal pneumococcal antibodies (Arm A);
and to describe the early rates of carriage (Arms A-F); to evaluate a single dose of PCV10 at
18 months of age (Arm F); and to evaluate the immunogenicity of Infanrix-hexa at 18 months of
age in children who have received three doses of Infanrix-hexa or three doses of Quinvaxem
(DTwP-Hib-HBV) in infancy.
Sample Size
The proposed infant sample size is 1200 with an allocation ratio of 3:3:5:4:5:4, resulting in
arm sizes of: A=150, B=150, C=250, D=200, E=250, F=200. Sample size calculations were based
on the primary outcomes for each of the two study questions: the post-primary series
immunogenicity comparing 1) a two dose (Arm C) and three dose (Arm A+B) PCV10 primary series
and 2) a two dose PCV13 (Arm E) and three dose PCV10 (Arm A+B) primary series. A
non-inferiority margin of 10% difference in absolute risk (Arm A+B minus Arm C or Arm E), as
used by regulatory authorities, is deemed clinically significant. The Farrington-Manning
(1990) method was used for the sample size/power estimation, assuming one-sided 5% type I
error. If the alternative hypotheses of non-inferiority are accepted for at least 7 out of 10
serotypes, overall non-inferiority will be declared. The power for testing individual
serotype hypotheses was calculated using PASS Software 2002. The power for rejecting the
overall null hypothesis was estimated by simulation, using a tailor-made simulation program
written for implementation in Stata with 10,000 replications. A sample size of 1200 results
in >99% power for rejecting the overall null hypothesis for each of the two study questions,
allowing for 5% loss to follow-up at four weeks post-primary series. An additional 200
participants aged 18 months (Arm G) will be recruited at the same time as participants from
Arms A-F reach 18 months of age, bringing the total sample size of the trial to 1400
participants.