The Role of BCG Vaccine in the Clinical Evolution of COVID-19 and in the Efficacy of Anti-SARS-CoV-2 Vaccines (SARS-CoV-2)
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ClinicalTrials.gov Identifier: NCT05507671 |
Recruitment Status :
Recruiting
First Posted : August 19, 2022
Last Update Posted : August 19, 2022
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Clinical trial with randomized allocation in two arms (BCG vaccine versus placebo) of volunteers at risk but not yet infected nor vaccinated against SARS-CoV-2. Initially will be evaluated whether BCG has a protective role against severe form of the disease. After participants are vaccinated against COVID-19, it will be evaluated whether BCG favors the vaccine's efficacy. Volunteers will be recruited in three Brazilian states, with at least 250 seronegative in each group. The BCG-trained immunity stimulus will be investigated by assessing cytokines at D0 and D60 in a subsample of 50 participants per group. Until being vaccinated against COVID-19, the participants will be followed for up to 6 months, with visits scheduled every 2 months for interviews and immunoglobulin G (IgG) anti-SARS-CoV-2 antibodies. Those who become symptomatic at any time during the follow-up will be guided and monitored remotely daily until the end of their clinical evolution. After being vaccinated against COVID-19, visits to participants will be adjusted for the time of vaccination (VD), 20 days after the 1st dose (P1) and at least 30 days (P2) after the 2nd dose, with the aim of comparing the efficacy of the anti-SARS-CoV-2 vaccine in the two groups in the short and medium term.
The study's conclusions on the efficacy of BCG in preventing severe COVID-19 will be based on: incidence of SARS-Cov-2 infection (defined as the emergence of IgG over the follow-up period); incidence of illness by COVID-19 (defined as the presence of symptoms among infected participants); intensity and duration of symptoms between cases of COVID-19 and frequency and duration of hospitalizations for COVID-19 in each group. The occurrence, type, frequency and intensity of adverse effects associated with vaccination of adults with BCG will be reported.
The study's conclusions regarding the effect of BCG on efficacy of vaccines against COVID-19 will be based on: frequency of anti-SARS-CoV-2 neutralizing antibodies after the vaccine' 1st and 2nd doses in both groups.
Condition or disease | Intervention/treatment | Phase |
---|---|---|
COVID-19 | Biological: BCG (Bacillus Calmette-Guérin) vaccine Other: Placebo | Phase 3 |

Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 556 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Intervention Model Description: | Two-arm study, BCG vaccine versus placebo, to assess the effect of BCG in preventing severe form of covid19 and improving the efficacy of anti-SARS-CoV-2 vaccines |
Masking: | Double (Participant, Outcomes Assessor) |
Masking Description: | Participants will not be informed if they received BCG or placebo. They will be informed that the injection may or may not give a local reaction regardless of what they receive. Blood samples for serological and cytokine studies will be coded and the laboratory technician will not know which samples are from participants who received BCG or placebo. |
Primary Purpose: | Prevention |
Official Title: | The Role of the Bacillus Calmette-Guérin Vaccine (BCG) in the Clinical Evolution of COVID-19 and in the Efficacy of Anti-SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2) Vaccines |
Actual Study Start Date : | May 27, 2021 |
Estimated Primary Completion Date : | December 31, 2022 |
Estimated Study Completion Date : | December 31, 2022 |

Arm | Intervention/treatment |
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Active Comparator: BCG vaccine
BCG (Bacillus Calmette-Guérin) vaccine - 0,1ml intradermal
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Biological: BCG (Bacillus Calmette-Guérin) vaccine
Application of BCG vaccine (0.1 ml intradermal) in the right arm deltoid insertion |
Placebo Comparator: Placebo
Solvent of BCG vaccine - 0,1ml intradermal
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Other: Placebo
Application of BCG solvent (0.1 ml intradermal) in the right arm deltoid insertion |
- Incidence of SARS-Cov-2 infection in both groups over the follow-up [ Time Frame: Up to six months from recruitment day ]Appearance of IgG antibodies (seroconversion) in the participants not yet vaccinated against COVID-19
- Incidence of illness by COVID-19 in both groups over the follow-up [ Time Frame: Up to six months from recruitment day ]Presence of symptoms among subjects not vaccinated against COVID-19 diagnosed with infection after D0 or seroconverted
- Intensity of the efficacy of the first dose of the vaccine against COVID-19 [ Time Frame: Up to six months from recruitment day ]Comparison of groups regarding frequency and titer (UI/ml) of anti-SARS-CoV-2 neutralizing antibodies after first dose of the specific vaccine, through the qualitative and semi-quatitative "SARS-CoV-2 Surrogate Virus Neutralization Test (sVNT)" Genscript Kit
- Duration of the efficacy of the second dose of the vaccine against COVID-19 [ Time Frame: One year from recruitment day ]Comparison of groups regarding frequency and titer (UI/ml) of anti-SARS-CoV-2 neutralizing antibodies after second dose of the specific vaccine, through the qualitative and semi-quatitative "SARS-CoV-2 Surrogate Virus Neutralization Test (sVNT)" Genscript Kit
- Intensity of clinical presentation of SARS-CoV-2 infection in both groups over the follow-up [ Time Frame: One year from recruitment day ]Comparison of groups regarding the frequency of infected with mild, moderate, serious or critical symptoms (according to detailed description in item 2.9-Clinical Evolution) and deaths by COVID-19 during the follow-up. The information will be obtained through daily telephone interview, self-completion of a questionnaire and hospitalization data.
- Duration of symptoms among participants with COVID-19 [ Time Frame: Six months from recruitment day ]Comparison of groups regarding the duration (number of days) of symptoms among participants who acquire COVID-19. The information will be obtained through daily telephone interview, self-completion of a questionnaire and hospitalization data
- Serum levels of cytokines after BCG vaccine stimulus (Trained Immunity effect) [ Time Frame: Two months from recruitment day ]Comparison of serum concentrations (pg/mL) of cytokines TNF-α, IFN-γ, IL-1β, IL-4, IL-6 and IL-10 at D0 versus D60 of 50 participants of BCG group compared to 50 participants of placebo group
- Adverse effects correlated with BCG vaccine in adults [ Time Frame: Six months from recruitment day ]Occurrence, type, frequency and intensity of adverse effects correlated with BCG revaccination obtained from obtained by interviewing those vaccinated with BCG (descriptive data)

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Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | Yes |
INCLUSION CRITERIA:
- Never been infected by SARS-Cov-2 - clinical history and absence of anti-SARS-CoV-2 IgM/IgG antibodies by the rapid test (immediate) and by serology test (later confirmation)
- Not having been vaccinated against COVID-19
- Be at least 18 years old
EXCLUSION CRITERIA:
- Have been vaccinated with BCG less than 6 months ago
- Have been vaccinated with BCG more than once in the past
- Present any classic contraindications for BCG - pregnancy, breastfeeding, acute febrile illness, severe allergy to one of the components, vaccination with other live vaccines in the last month (measles, yellow fever, herpes zoster), immunosuppression for any cause (congenital, illness, use of corticosteroids or immunosuppressants)
- Have had tuberculosis or contacted someone with tuberculosis
- Present signs of any current acute illness or have had a severe illness less than 15 days
- Present a skin lesion at the vaccine application site (right deltoid muscle)
- History of severe allergic reactions to any product: urticaria, glottis edema, angioedema, respiratory failure, bronchospasm
- History of serious autoimmune diseases: systemic lupus erythematosus, Crohn's disease, ulcerative colitis, multiple sclerosis, hemolytic anemia, ankylosing spondylitis, pemphigus and others
- Immunocompromise for any reason (congenital, illness, use of corticosteroids or immunosuppressants)
- Presenting a risk comorbidity for severe COVID-19, such as: poorly controlled hypertension, decompensated heart disease (chronic, congenital or ischemic), pulmonary disease (chronic pneumopathy, poorly controlled asthma, chronic interstitial pneumopathy, others ...), disease advanced chronic kidney disease (use of dialysis), transplantation (of solid organs or bone marrow), uncontrolled diabetes

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT05507671
Contact: Simone Ladeia-Andrade, MD PhD | 2125621302 ext +55 | sladeia@ioc.fiocruz.br | |
Contact: Marcelo U Ferreira, MD PhD | 1130917746 ext +55 | muferrei@usp.br |
Brazil | |
Policlínica Cardoso Fontes | Recruiting |
Manaus, Amazonas, Brazil, 69010-030 | |
Contact: Irineide A Antunes, MD +55(92)3627-8204 irineide_antunes@yahoo.com.br | |
Contact: Lucilaide O Santos, MD +55(92)994371916 santos.lucilaide@gmail.com | |
Universidade Federal de Juiz de Fora | Recruiting |
Juiz de Fora, Minas Gerais, Brazil, 36036-900 | |
Contact: Kezia KG Scopel, PhD +55(32)21023219 keziagscopel@gmail.com | |
Contact: Sandra HC Tibiriça, MD PhD +55(32)988537708 shctibi@gmail.com | |
Centro Universitário do Pará | Recruiting |
Belém, Pará, Brazil, 66613-903 | |
Contact: Haroldo J Matos, MD PhD +55(91)993251672 haroldodematos@gmail.com | |
Oswaldo Cruz Foundation | Not yet recruiting |
Rio de Janeiro, Brazil, 21040-360 | |
Contact: Simone L Andrade, MD-PhD +55-21-25621302 sladeia@ioc.fiocruz.br | |
Contact: Marcelo U Ferreira, MD-PhD +55-11-30917746 muferrei@usp.br | |
Sub-Investigator: Simone L Andrade, PhD |
Principal Investigator: | Simone Ladeia-Andrade, MD PhD | Oswaldo Cruz Institute, Oswaldo Cruz Foundation | |
Study Chair: | Igor C Johansen, PhD | University of Campinas, Brazil | |
Study Chair: | Marcelo U Ferreira, MD PhD | University of Sao Paulo | |
Study Chair: | Kezia KG Scopel, PhD | Universidade Federal de Juiz de Fora | |
Study Chair: | Helena LC Santos, PhD | Oswaldo Cruz Institute, Oswaldo Cruz Foundation | |
Study Chair: | Haroldo J Matos, MD PhD | Centro Universitário do Pará | |
Study Chair: | Irineide A Antunes, MD | Policlínica Cardoso Fontes de Manaus | |
Study Chair: | Lucilaide O Santos, MD | Fundação de Medicina Tropical Doutor Heitor Vieira Dourado | |
Study Chair: | Sandra HC Tibiriça, MD PhD | Universidade Federal de Juiz de Fora |
Publications:
Responsible Party: | Oswaldo Cruz Foundation |
ClinicalTrials.gov Identifier: | NCT05507671 |
Other Study ID Numbers: |
BCG-COVID/484016302711489/2020 |
First Posted: | August 19, 2022 Key Record Dates |
Last Update Posted: | August 19, 2022 |
Last Verified: | August 2022 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Studies a U.S. FDA-regulated Drug Product: | No |
Studies a U.S. FDA-regulated Device Product: | No |
COVID-19 SARS-CoV-2 BCG vaccine |
Bacillus Calmette-Guérin clinical trials trained immunity |
COVID-19 Respiratory Tract Infections Infections Pneumonia, Viral Pneumonia Virus Diseases Coronavirus Infections Coronaviridae Infections |
Nidovirales Infections RNA Virus Infections Lung Diseases Respiratory Tract Diseases BCG Vaccine Adjuvants, Immunologic Immunologic Factors Physiological Effects of Drugs |