The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been endorsed by the ANZCTR. Before participating in a study, talk to your health care provider and refer to this information for consumers
Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Type of registration
Prospectively registered

Titles & IDs
Public title
A comparison of the immune response to two different oral polio vaccine regimes in Pakistan
Scientific title
Comparison of immunogenicity of Monovalent oral polio vaccine (mOPVI) administered at short intervals with Monovalent (mOPVI) and Bivalent (bOPV1,3) oral polio vaccine given at standard intervals in healthy infants in Pakistan: a randomized trial
Secondary ID [1] 262660 0
Nil known
Universal Trial Number (UTN)
Trial acronym
OPV Short Interval Trial
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Poliomyelitis 268366 0
Condition category
Condition code
Public Health 268500 268500 0 0
Infection 268521 268521 0 0
Other infectious diseases
Oral and Gastrointestinal 268522 268522 0 0
Normal oral and gastrointestinal development and function

Study type
Description of intervention(s) / exposure
1. Standard trivalent oral poliovirus vaccine (tOPV), in a 10:1:6 formulation, containing at least 1 000 000 TCID50 per dose of Sabin -strain poliovirus type 1, at least 100 000 TCID50 per dose of Sabin-strain poliovirus type 2
and at least 600 000 TCID50 per dose of Sabin-strain poliovirus type 3 is given at birth to all 4 groups of subjects.
2. Monovalent type 1 oral poliovirus vaccine (mOPV1) containing at least1 000 000 TCID50 per dose of Sabin- strain poliovirus type 1 is given at 42 days (6 weeks of age) and 7 days later (group 1) or 14 days later (group 2) or 30 days later (group 3).
3. The oral bivalent vaccine containing at least 1 000 000 CCID50 per dose of Sabin poliovirus type 1 and 600 000 CCID50 per dose of Sabin poliovirus type 3 is given to group 4 at 42 days (6 weeks of age) and 30 days later .
Intervention code [1] 267006 0
Comparator / control treatment
The control group 1 will receive tOPV at birth, mOPV1 at 42 days (6 weeks of age) and the last dose of mOPV1 30 days later (10 weeks of age).
Control group

Primary outcome [1] 269243 0
- A schedule of two doses of mOPV1 administered at a 7 or 14 day interval following a previous mOPV1 dose administered at 42 days induces comparable levels of seroconversion against poliovirus type 1 compared to (i) a schedule of two doses of mOPV1; or (ii) two doses of bOPV1,3 administered at a standard interval of 30 days apart.
The principal purpose of the study is to demonstrate the non-inferiority of shorter intervals (7 or 14 days) between two doses of mOPV1 vaccine compared to 2 doses of mOPV1 and bOPV1,3 administered at standard intervals (30 days apart). This is a phase IV study, and the data generated by this clinical trial are intended to guide programmatic action.
Timepoint [1] 269243 0
Blood sample at birth, 42 days, 79 days, 86 days, and 102 days
Secondary outcome [1] 279212 0
Adverse events following vaccine administration will be monitored. All participants will be informed to contact the study primary investigators or study physicians at the primary care area clinics if the child requires medical care. Should a serious illness arise requiring a physician visit or hospitalization, parents will receive instructions on who to contact.
No serious adverse effect following the use of live-attenuated Sabin strains in this very young study population (<3 months of age) have been reported.
In the unforeseen instance of serious adverse events after routine DPT, free transport and hospital referral to a tertiary care public sector hospital (National Institute of Child Health) will be arranged as well as provision of cost of care during hospital stay.
The methods and timing for assessing, recording, and analyzing safety parameters:
The study questionnaire will record data during each visit, and for the preceding period, if applicable.
Procedures for eliciting reports of and for recording adverse event and intercurrent illnesses:
As discussed above, parents will be encouraged to use the PHCs run by the study staff for reporting adverse events and seeking care for intercurrent illnesses. They also have the mobile phone number of their local CHW to call for any problem. Adverse events will be recorded in the study forms.
The type and duration of follow-up of subjects after adverse events: Should adverse events occur, referral and cost of medical care at a tertiary public sector hospital will be provided.
Timepoint [1] 279212 0
After the first dose at birth, at 42 days, at 79 days, at 86 days and at 102 days

Key inclusion criteria
Infants born healthy (> 2.5 kg birth weight, immediate cry, no neonatal IMCI danger signs) at the study sites (home or health facility births assisted by study-Trained Birth Attendants/other health personnel) and not planning to travel away during entire the study period (birth-102 days).
Minimum age
0 Days
Maximum age
0 Days
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
High-risk newborns will be excluded, as well as newborns requiring hospitalization, birth weight below 2.5 kg, cry >2 minutes, and with any neonatal IMNCI danger signs, residence >30 km from study site, or family is planning to be absent during the birth - 102 day study period. A diagnosis or suspicion of immunodeficiency disorder (either in the participant or in a member of the immediate family - e.g. several early infant deaths, household member on chemotherapy) will render the newborn ineligible for the study. Subjects will be re-screened for eligibility at the 6 week visit before randomization to study arms. Infants with illness requiring hospitalization, weight <2.5 kg, family planning to be away during the next 10 weeks, or unwilling to have another blood draw will be excluded from randomization. The families of babies with exclusion criteria will be informed about immediate treatment options if their baby is sick (hospital referral and in case of refusal centre-based outpatient care), need for receipt of routine immunizations, and reassured about long term continued assessment and primary level care at the PHC.

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Expectant mothers and fathers (if available) will be informed about the study and invited to participate. The parents will be asked to give permission for collection of cord blood at birth or baby's peripheral blood through venepuncture within 24 hours of birth. Informed consent for trial participation will be sought by study personnel at any one of the following time points: late pregnancy follow up visits (36-37 week of gestation) closest to expected date of delivery (EDD); within 24 hours of birth in case the first option could not be availed. Good liaison with the family’s identified birth attendant (traditional birth attendant, TBA, or skilled attendant) will be maintained to ensure presence at time of delivery. The birth attendant will be incentivized to inform our study personnel of impending births if family provides informed consent during late pregnancy follow-up.
After delivery, an evaluation will be done to see whether the newborn meets the eligibility criteria for inclusion into the study (weight >2.5kg, immediate cry, no neonatal danger signs as per IMNCI guidelines). If eligible, the blood (1 ml) will be collected in vaccutainer gel tubes and labelled appropriately. A birth dose of tOPV will be administered to all subjects post informed consent and cord/peripheral blood collection. Cord blood will be collected from babies when a study staff member can be present to ensure study procedures are followed. For infants born between the hours of 9pm at night to 9 am in the morning, which is outside our clinic working hours, the following procedure will be in place: the birth attendant will call a trained community health worker residing locally to collect blood from the cord. In cases of failure to collect cord blood for any reason, peripheral blood will be collected the next day within 24 hours of birth, if, the parents consent. A trained phlebotomist will conduct the venepuncture with optimal consideration to maximizing asepsis and minimizing discomfort to the newborn, allowing a maximum of two attempts.
The parents will be advised to return to the local Primary Health Centre (PHC) at day 42 (6 weeks) of life. Local CHWs will accompany the babies and mothers to the centre on day 42. The infants will undergo a physical exam by a study physician at the center and well infants will be randomized to one of four groups, three receiving the first dose of mOPV1 and the fourth, bivalent OPV1,3 at the day 42 (6 weeks) visit. The randomization procedure will be handled by AKU’s Clinical Trials Unit (CTU) who will inform regarding the infant’s study arm assignment through a text message. One ml of peripheral blood will be collected from each subject after vaccination is complete (second blood sampling).
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Randomization for assignment to a study arm will take place using a random number generator. This is not a blinded study. Assignments for randomization will be done in a blinded manner by staff based at the Clinical Trial Unit of AKU who will inform the study physician about each infant’s assignment.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?

Intervention assignment
Other design features
different groups of participants receive different interventions during the same time span of the study
Phase 4
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Reason for early stopping/withdrawal
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment outside Australia
Country [1] 3722 0
State/province [1] 3722 0

Funding & Sponsors
Funding source category [1] 267484 0
Name [1] 267484 0
World Health Organization (WHO)
Address [1] 267484 0
Avenue Appia 20
Geneva CH-1211
Country [1] 267484 0
Primary sponsor type
Department of Paediatrics and Child Health, Aga Khan University
Aga Khan University (AKU)
Stadium road
P.O. Box 3500
Karachi, 74800
Secondary sponsor category [1] 266525 0
Name [1] 266525 0
Address [1] 266525 0
Country [1] 266525 0
Other collaborator category [1] 252115 0
Government body
Name [1] 252115 0
Centers for Disease Control and Prevention(CDC)
Address [1] 252115 0
1600 Clifton Road
NE Mailstop G17,
Atlanta, GA 30 333
Country [1] 252115 0
United States of America

Ethics approval
Ethics application status
Ethics committee name [1] 269446 0
Ethics committee address [1] 269446 0
Avenue Appia 20
Geneva CH-1211
Ethics committee country [1] 269446 0
Date submitted for ethics approval [1] 269446 0
Approval date [1] 269446 0
Ethics approval number [1] 269446 0

Brief summary
An Emergency Action Plan for polio eradication in Pakistan in 2011 has recently been launched by the President of Pakistan which incorporates independent monitoring of immunization activities and increased political accountability at national, federal, district and union council levels, in the hope that eradication goals can be met quickly. As part of this effort, national EPI officers, WHO Polio Eradication Initiative, and other concerned partners are exploring ways of urgently suppressing polio virus activity in Pakistan. A proposed method to attain this is by conducting short-interval polio vaccination campaigns using type 1 monovalent oral polio vaccine (mOPV1) against the prevalent serotype (WPV1), particularly in areas with limited access due to security concerns. An earlier clinical trial in Egypt had demonstrated higher birth dose sero-conversion against WPV1, the main circulating global polio strain using mOPV1 compared to trivalent oral polio vaccine (tOPV) in 2006, leading many countries to use mOPV1 in subsequent supplemental immunization activities (SIA). A randomized, double-blinded trial in three centres in India has also established superiority of monovalent vaccines over trivalent and non inferiority of bivalent compared with monovalent OPV1 and OPV3. One of the major lessons learnt since Global Polio Eradication Initiative (GPEI) began, has been optimizing the impact of the new, highly immunogenic monovalent OPVs. This has proven difficult in practice, and in some settings has contributed to alternating outbreaks of the remaining wild poliovirus type 1 (WPV1) and wild poliovirus type 3 (WPV3) serotypes. The fast-tracked development and introduction of a bivalent OPV1&3 formulation in 2009, and its large-scale use in Supplemental Immunization Activities (SIAs) could complement the continued use of trivalent OPV in some SIAs and in routine immunization, as well as of monovalent OPVs in some mop-ups and SIAs where appropriate.
Typically, SIA rounds are separated by an interval of ~30 days. It is possible that the same level of immunogenicity could be attained by shorter interval spacing as compared to the 30 day interval, allowing multiple SIA rounds to be conducted quickly to eradicate WPV circulation from an area in a very short time period of a few weeks instead of the current situation of having to conduct several rounds over a period of months and more children getting infected in areas of high WPV transmission. For example, in Pakistan, in 2010, intervals between SNIDs ranged from 5-9 weeks. Shorter interval SIA rounds would also have the added benefit of allowing multiple "sweep throughs" in areas of high transmission in a short period of time, increasing the chance that children missed on a previous round will get vaccinated in subsequent rounds. However, there is limited knowledge on the effect of shorter intervals of mOPV vaccination on immunogenicity levels in young children and comparative efficacy of mOPV1 versus bivalent oral polio vaccine containing serotypes 1 and 3 (bOPV1&3). It is assumed more vaccinations administered within a shorter period of time would be non-inferior to regular intervals, defined as an immunization round every 30 days. Although shorter interval immunization rounds were carried out in Somalia, Afghanistan, and Kenya, and were successful in eradicating polio from these areas, there was no documentation of immunogenicity levels in these children.
In order to generate data on 2-dose seroconversion with short interval monovalent OPV1 administration, and standard interval monovalent OPV1 and bivalent OPV (1&3) administration, we propose to assess additional programmatic options for short-interval SIA rounds in Pakistan and conduct a clinical trial in Karachi, Pakistan where immunogenicity of supplemental mOPV doses in a naive population (newborns) needs objective evaluation.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 32876 0
Address 32876 0
Country 32876 0
Phone 32876 0
Fax 32876 0
Email 32876 0
Contact person for public queries
Name 16123 0
Dr. Jackie Fournier-Caruana
Address 16123 0
World Health Organization
Avenue Appia 20
Geneva CH-1211
Country 16123 0
Phone 16123 0
+41 794 755519
Fax 16123 0
Email 16123 0
Contact person for scientific queries
Name 7051 0
Dr. Jackie Fournier-Caruana
Address 7051 0
World Health Organization
Avenue Appia 20
Geneva CH-1211
Country 7051 0
Phone 7051 0
+41 794 755519
Fax 7051 0
Email 7051 0

No information has been provided regarding IPD availability
Summary results
No Results