The first single-shot coronavirus vaccine has entered the final stages of testing in the US in an international trial that will recruit up to 60,000 participants.
The experimental vaccine is being developed by pharmaceutical giant Johnson & Johnson and is the fourth vaccine to enter the large, phase-3 trials in the United States that will determine whether they are effective and safe.
Unlike the three vaccines developed by Moderna, Pfizer and BioNTech, and AstraZeneca and the University of Oxford, which require a re-visit and second shot three to four weeks after the first one to trigger a protective immune response, J&J will be initially testing a single dose.
The J&J vaccine can also be stored in liquid form at refrigerator temperatures for three months, whereas two of the front-runner candidates must be frozen or kept at ultra-cold temperatures for long-term storage.
Paul Stoffels, chief scientific officer of J&J, said there may be enough data to have results by the end of the year and said the company plans to manufacture 1 billion doses next year.
Three other vaccine candidates have a head start, with U.S. trials that began earlier in the summer, but the vaccine being developed by Janssen Pharmaceutical Companies, a division of J&J, claims several advantages that could make it logistically easier to administer and distribute.
The J&J vaccine will be shipped frozen, but can be stored in liquid form at refrigerator temperatures for three months.
“A single-shot vaccine, if it’s safe and effective, will have substantial logistic advantages for global pandemic control,” said Dan Barouch, director of the Center for Virology and Vaccine Research at Beth Israel Deaconess Medical Center in Boston, who partnered with J&J to develop the vaccine.
The United States has invested billions of dollars in an array of vaccine technologies, including close to $1.5 billion to support the development of the J&J vaccine and an advance purchase of 100 million doses.
The J&J vaccine is the second to use a viral-vector approach, taking a harmless virus and inserting into it a gene that contains the blueprint for a distinctive part of the novel coronavirus.
Data from early-stage human trials that included 400 participants in the US and Belgium was scheduled to be submitted to a preprint server on Wednesday (September 23), but Stoffels said that overall, the vaccine showed that it triggered a promising immune response and that side effects of the vaccine were tolerable, including some fevers that resolved within one to two days.