US-based pharmaceutical company Moderna Inc's COVID-19 vaccine candidate—mRNA-1273—entered phase 3 of clinical trials on 27 July. The vaccine has been developed by Moderna in partnership with the National Institute of Allergy and Infectious Diseases (NIAID), which is affiliated to the National Institutes of Health (NIH) of the United States.
As many as 30,000 volunteers will be part of the third stage of clinical trials, to be held at different clinical research sites across the United States.
Earlier this month, Moderna and NIAID published encouraging results from phase 1 human trials of the vaccine in the New England Journal of Medicine—the trials had shown that the vaccine could promote antibody activity to neutralise the virus. Phase 2 of the clinical trials began in May 2020.
Read more: All you wanted to know about Moderna’s mRNA vaccine
The news comes shortly after ChAdOx1 nCoV-19 phase 1/2 results showed it induces strong immunity—ChAdOx1 nCoV-19 is another vaccine candidate being co-developed by the University of Oxford and AstraZeneca, a pharmaceutical major.
According to Dr Anthony Fauci, the director of NIAID, preventive measures such as using face covers, the practice of physical distancing, along with quarantine and isolation of those infected do help in limiting the spread of the new coronavirus infection, but there is an urgent need for a safe and effective vaccine in order to stop further transmission of the disease.
"Results from early-stage clinical testing indicate the investigational mRNA-1273 vaccine is safe and immunogenic, supporting the initiation of a phase 3 clinical trial," Dr Fauci said. "This scientifically rigorous, randomised, placebo-controlled trial is designed to determine if the vaccine can prevent COVID-19 and for how long such protection may last."
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Phase 1 of the mRNA-1273 clinical trials was designed to include participants in the 18-55 year age bracket but had included participants older than 55 years of age as well. That trial was conducted on 120 participants; while phase 3 will include a much larger cohort in the trial.
NIH director Francis S. Collins said that the accelerated development of the vaccine is because of the steadily rising number of cases and deaths all over the world, and maintained that they were still aiming to be able to begin distribution before the end of the year, as "it's the right goal for the American people".
Read more: WHO doesn’t expect COVID-19 vaccine before 2021
About 89 research sites have been identified in the US where the vaccine will undergo phase 3 of its clinical trials. The investigations will also include the use of public health data and the technique of incidence trajectory modelling to identify high-incidence areas and emerging hotspots, to be able to fast-track enrollments from such areas.
Phase 3 of the trials will involve testing the safety of the vaccine and to find out if administering two doses can prevent the onset of symptomatic COVID-19. Scientists are also hoping to find out if the vaccine can prevent both severe symptoms of COVID-19, as well as preventing asymptomatic disease. The trial is also an attempt to find out if the vaccine can prevent future deaths due to the infection, and the dosage that is needed to prevent the onset of COVID-19.