As researchers from around the world work tirelessly to develop a vaccine for COVID-19, an inexpensive century-old vaccine may have potential in the short-term to provide a level of protection against the novel coronavirus.
A UHN-led study,
COBRA (COVID-19 BCG Risk Assessment) is the first in Canada to investigate if the vaccine to prevent tuberculosis (Bacille Calmette Guerin, BCG) can reduce the incidence and the severity of COVID-19 infection.
BCG's potential in the fight against the novel coronavirus is being investigated in other parts of the world – recently a
randomized study has shown that BCG protects against viral and respiratory infections, but has not been studied specifically for COVID-19.
The Canadian-led COBRA trial is using an improved version of the vaccine, provided by Verity Pharmaceuticals, which researchers expect will help muster a stronger immune response.
"If the vaccine is successful in providing non-specific protection against COVID-19, it could be rapidly applied in Canada and worldwide to bridge the gap before a disease-specific vaccine is developed," says Dr. Alexandre Zlotta, surgeon and associate scientist at UHN, and Principal Co-Investigator of COBRA.
"The big advantage here is this vaccine has been given to billions of people around the world in the past decades. It is safe and readily available. If the study is successful, this could become an important strategy to control the secondary waves of the pandemic."
COBRA is a double-blind placebo-controlled study done in collaboration with trials in Germany and the United States. The study is being done in partnership with Toronto Police Service, Peel Regional Police, and Toronto Fire Services and now it is also open for UHN staff.
How can UHN staff participate?
COBRA is open to all UHN staff – clinical, non-clinical, research and trainees.
UHN staff can participate by calling 416-946-4501 ext. 7510, or emailing the study team at
COVIDBCGstudy@uhn.ca. Staff will schedule you into one of the upcoming clinics at UHN.
Additional information
Participants of the study will report back on potential symptoms and their severity
– including adverse events or hospitalizations – as well as overall quality of life. They will also undergo blood-based testing to understand the vaccines mechanism of action.
As this is a placebo-controlled trial, half of participants will receive placebo. Data analysis is expected by April, 2021 and results to be publicly communicated in May, 2021. These dates are subject to change.
A special independent committee will review the study midway. If there is evidence that the vaccine is clearly helping boost participants' immune response against COVID-19, the committee may decide to stop the clinical trial so that all participants – including those who received placebo – can be offered the protective vaccine.
The study is being funded by The Princess Margaret Cancer Foundation. Verity Pharmaceuticals provided the recombinant Bacillus Calmette-Guérin (rBCG) vaccine doses used in the trial. More information is available on
COBRA's website, through email COVIDBCGSTUDY@UHN.CA or by calling the COBRA HOTLINE at 416-946-4501 EXT. 7510.
Disclosure: Dr. Neil Fleshner, one of COBRA's co-investigators, is part of Verity Pharmaceuticals' Scientific Advisory Board.
