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CompletedNCT04445428Updated Apr 7, 2026Results posted

OPV as Potential Protection Against COVID-19

A Phase 4 interventional study of oral polio vaccine + information and Information in Poliovirus Vaccine, Oral, COVID and Mortality, sponsored by Bandim Health Project. Completed at 1 site in Guinea-Bissau. Open to participants aged 50 Years and older. Per ClinicalTrials.gov, last updated 2026-04-07.

Sponsored by Bandim Health Project · Phase 4, Interventional, and Prevention

Phase
Phase 4
Study type
Interventional
Enrollment
3,729
Allocation
Randomized
Ages
50 Years and older
Sex
All
01

Study summary

Since the 1960s, studies have shown that oral polio vaccine (OPV) may have beneficial non-specific effects, reducing morbidity and mortality from other infections than polio. Such beneficial non-specific effect have been observed for other live vaccines, including measles, smallpox and BCG vaccine. For BCG, the vaccine for which the mechanism has been studied the most, the effects appear to be mediated through the innate immune system. The COVID-19 pandemic caused by the novel coronavirus SARS-CoV-2 has now caused over 7.1 million cases and >400,000 deaths worldwide. As everywhere else, it is anticipated that in Africa the older part of the population will be at risk of severe COVID-19. OPV is widely used in Africa, but for children. Both polio and coronavirus are positive-strand RNA viruses, therefore it is likely that they may induce and be affected by common innate immune mechanisms.

In a randomised trial at the Bandim Health Project in Guinea-Bissau, the investigators will assess the effect of providing OPV vs no vaccine to 3400 persons above 50 years of age. The trial will have the power to test the hypothesis that OPV reduces the combined risk of morbidity admission or death (composite outcome) by at least 28% over the subsequent 6 months.

02

Conditions studied

  • Poliovirus Vaccine, Oral
  • COVID
  • Mortality
  • Morbidity
  • Non-Specific Effects of Vaccines
03

Who can participate

Ages eligible
50 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

Inclusion criteria

  • Living in a household which has had a census visit conducted after 1 January in 2017. Age above 50.

Exclusion criteria

Exclusion Criteria:

  • Previous adverse events to OPV; Previous documented COVID-19; Acute severe infection.
04

Study design

Phase
Phase 4
Primary purpose
Prevention
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Double (Care provider, Outcomes assessor)
Enrollment
3,729 participants (actual)

Study arms

  • Experimental
    Intervention

    Standard dose bivalent oral polio vaccine, 0.1ml, and information regarding prevention of COVID-19

    Biological: oral polio vaccine + information · Behavioral: Information

  • Other
    Control

    Information regarding prevention of COVID-19

    Behavioral: Information

Interventions

  • Biologicaloral polio vaccine + information

    Bivalent OPV (GSK), 0.1 ml administered orally on a sugar lump

  • BehavioralInformation

    Advice regarding how to protect oneself from COVID-19

05

What researchers measure

Primary outcomes

  1. Mortality or Infectious Disease Causing Consultation or Admission (Composite Outcome)

    Composite outcome of the first of death, hospitalisation for infection and/or consultation for infection at the health centre

    Time frame: 6 months

Secondary outcomes

  1. Self-reported Morbidity

    Episodes with self-reported infectious disease morbidity.

    Time frame: 6 months

  2. Suspected COVID-19 Infection

    Episodes with self-reported infectious disease morbidity suspected to be caused by COVID (three or more of the following: fever, cough, sore thought, extreme fatigue, loss of smell/taste).

    Time frame: 6 months

  3. Mortality

    Either of the components of the composite outcome.

    Time frame: 6 months

  4. Hospital Admission for Infectious Disease

    Either of the components of the composite outcome included repeated events.

    Time frame: 6 months

  5. Consultations for Infectious Disease

    Either of the components of the composite outcome included repeated events.

    Time frame: 6 months

06

Results

Posted Apr 7, 2026

Participant flow

Participant flow — Overall Study
MilestoneInterventionControl
Started15802149
Completed15802146
Not completed03

Outcome measures

SecondarySelf-reported Morbidity

Episodes with self-reported infectious disease morbidity.

Time frame:
6 months
Reported as:
Number · events
Self-reported Morbidity
eventsInterventionControl
Self-reported Morbidity27243326
Statistical analysis
  • Intervention vs Control · Hazard ratio (hr): 1.10 · 95% CI 1.03 to 1.17
SecondarySuspected COVID-19 Infection

Episodes with self-reported infectious disease morbidity suspected to be caused by COVID (three or more of the following: fever, cough, sore thought, extreme fatigue, loss of smell/taste).

Time frame:
6 months
Reported as:
Number · Number of events
Suspected COVID-19 Infection
Number of eventsInterventionControl
Suspected COVID-19 Infection162187
Statistical analysis
  • Intervention vs Control · Hazard ratio (hr): 1.14 · 95% CI 0.89 to 1.47
SecondaryMortality

Either of the components of the composite outcome.

Time frame:
6 months
Reported as:
Count of participants · Participants
Mortality
ParticipantsInterventionControl
Mortality2838
SecondaryHospital Admission for Infectious Disease

Either of the components of the composite outcome included repeated events.

Time frame:
6 months
Reported as:
Number · Number of events
Hospital Admission for Infectious Disease
Number of eventsInterventionControl
Hospital Admission for Infectious Disease3562
SecondaryConsultations for Infectious Disease

Either of the components of the composite outcome included repeated events.

Time frame:
6 months
Reported as:
Number · Number of events
Consultations for Infectious Disease
Number of eventsInterventionControl
Consultations for Infectious Disease442528
PrimaryMortality or Infectious Disease Causing Consultation or Admission (Composite Outcome)

Composite outcome of the first of death, hospitalisation for infection and/or consultation for infection at the health centre

Time frame:
6 months
Reported as:
Count of participants · Participants
Mortality or Infectious Disease Causing Consultation or Admission (Composite Outcome)
ParticipantsInterventionControl
Mortality or Infectious Disease Causing Consultation or Admission (Composite Outcome)169239
Statistical analysis
  • Intervention vs Control · Hazard ratio (hr): 0.97 · 95% CI .79 to 1.18Hazard ratio adjusted for zone and age

Adverse events

Collected over 6 months. Non-serious events are listed at a 0% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
Intervention28/1,580 (1.8%)0/1,580 (0%)0/1,580 (0%)
Control38/2,146 (1.8%)0/2,146 (0%)0/2,146 (0%)

Baseline characteristics

Age, Continuous
Age, Continuous(Years)InterventionControlTotal
Median59 (54 to 66)60 (55 to 66)60 (55 to 66)
Sex: Female, Male
Sex: Female, Male(Participants)InterventionControlTotal
Female93712862223
Male6438631506
Race and Ethnicity Not Collected
Race and Ethnicity Not Collected(Participants)InterventionControlTotal
Count of participants——0
Race and Ethnicity Not Collected
Race and Ethnicity Not Collected(Participants)InterventionControlTotal
Count of participants——0
07

Study locations

1 site
  • Bandim Health Project
    Bissau, Guinea-Bissau
08

References and documents

Publications

  • Fisker AB, Martins JSD, Nanque LM, Jensen AM, Ca EJC, Nielsen S, Martins CL, Rodrigues A. Oral Polio Vaccine to Mitigate the Risk of Illness and Mortality During the Coronavirus Disease 2019 Pandemic: A Cluster-Randomized Trial in Guinea-Bissau. Open Forum Infect Dis. 2022 Sep 11;9(9):ofac470. doi: 10.1093/ofid/ofac470. eCollection 2022 Sep. PubMed 36193229 ↗

Study documents

  • Study protocol · May 19, 2020
  • Statistical analysis plan · Nov 16, 2021

Documents are hosted by the registry — open the source record to download them.

Individual participant data

Plan to share: No — Provided request, data can be made available

09

Registry details

Key details

Study ID
NCT04445428
Lead sponsor
Bandim Health Project
Responsible party
Sponsor
First posted
Jun 24, 2020
Start date
Jul 15, 2020
Primary completion
Jan 31, 2022
Completion
Jun 15, 2022
Results posted
Apr 7, 2026
Last update
Apr 7, 2026

Study contacts

Ane Fisker, MD, PhD
principal investigator · Bandim Health Project

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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