Global trial to test whether MMR vaccine protects front-line healthcare workers against COVID-19
Washington University School of Medicine in St. Louis (WUSTL) is the clinical coordinating center for an international trial aimed at evaluating on a large scale whether the MMR vaccine can protect against COVID-19, according to their report.
An international research network of physicians and scientists is launching a clinical trial to evaluate whether the vaccine for measles, mumps and rubella (MMR) can protect front-line healthcare workers against infection from SARS-CoV-2, the virus that causes COVID-19. The trial aims to enroll up to 30,000 healthcare workers globally.
WUSTL is the clinical coordinating center for this ambitious, international trial, which is the first to evaluate on a large scale whether the MMR vaccine can protect against COVID-19. The trial is co-led by Washington University, University College London and the University of the Witwatersrand in Johannesburg, via the CROWN (COVID-19 Research Outcomes Worldwide Network) Collaborative and involves researchers from institutions in African, European and North American countries.
The MMR vaccine has been given safely to hundreds of millions of people around the world since it was approved nearly 50 years ago, and has successfully reduced the incidence of measles, mumps and rubella worldwide. Typically, the vaccine is given to children, with most getting two doses before age six. The research team leading the trial points to growing evidence that suggests the MMR vaccine may have benefits beyond protecting against measles, mumps and rubella. It could broadly boost an individual’s immunity and may prevent infection from SARS-CoV-2 for a limited period. This is because the vaccine carries small amounts of live, weakened viruses that could train the body’s immune system to fight multiple pathogens.
“We know that the MMR vaccine is safe, and we think there are two main reasons that it could prevent COVID-19,” said one of the collaborative’s principal investigators, Michael S. Avidan, MBBCh, the Dr. Seymour and Rose T. Brown Professor and head of the Department of Anesthesiology at Washington University. “The first is this vaccine includes small amounts of live but very weakened measles, mumps and rubella viruses. This type of vaccine appears to strengthen the body’s immune response to infections in general, not just to the viruses in that particular vaccine.”
A second reason the MMR vaccine may be effective is that there are similarities between the weakened viruses in the vaccine and the SARS-CoV-2 virus that causes COVID-19. All of these viruses have similar proteins on their surfaces that are involved in infecting cells in the body, so the researchers think that antibodies made in response to the MMR vaccine also may recognize and fight the SARS-CoV-2 virus.
Unlike the drugs remdesivir and dexamethasone, the only medications so far identified as being helpful in treating COVID-19, the MMR vaccine would not be used to aid recovery from illness. Instead, the researchers want to learn whether the vaccine can elicit an immune response that slows the spread of the virus and protects front-line health-care workers who work in high-risk settings from developing COVID-19. The vaccine also will be examined to see whether it might reduce the severity of illness for those who do become infected.
Most healthcare workers enrolled in the trial will receive a booster, as they likely received the vaccine as children. But in some countries where the MMR vaccine isn’t widely given to children, healthcare workers may be receiving the vaccine for the first time.
The CROWN Coronavirus Prevention (CORONATION) adaptive trial platform launched as the global pandemic was beginning. The researchers designed the platform to be nimble and to assess multiple interventions. They initially planned to evaluate the anti-malaria drug chloroquine. However, as emerging data showed the drug was not as promising as originally thought, the trial platform quickly pivoted to evaluate a different intervention.
“The CROWN Collaborative research platform was designed to rapidly evaluate preventive and therapeutic interventions to learn which ones work and which ones do not,” Avidan said. “Our goal from the start has been to identify interventions that work and make them available to the people around the world who will benefit most.”
The CROWN CORONATION trial is funded by a $9 million grant from the COVID-19 Therapeutics Accelerator — an initiative launched by the Bill & Melinda Gates Foundation, Wellcome, and Mastercard, with support from an array of public and philanthropic donors. The Therapeutics Accelerator works to speed up the response to the COVID-19 pandemic by identifying, assessing, developing and scaling up treatments. The study will recruit front-line healthcare workers from Canada, Ghana, Ireland, South Africa, Uganda, United Kingdom, United States, Zambia and Zimbabwe.
“If we discover that the MMR vaccine can help train the body’s immune response to SARS-CoV-2 infection, then we will have something to administer very quickly, while waiting for more specific vaccines and preventive therapies to be developed,” Laurence Lovat, MD, PhD, a professor of gastroenterology and biophotonics, is the study leader in the United Kingdom said. “If the trial shows that the MMR vaccine can boost the body’s general immune response, we believe it may enhance the effectiveness of vaccines currently in development to prevent SARS-CoV-2 infection.”