Researchers and developers are racing to develop new and improved methods for containing Covid-19 and stopping the ongoing pandemic. This global effort has resulted in approval of multiple vaccines throughout the world. These vaccines vary in structure and efficacy. In the United States, the FDA gave emergency use authorization for two extremely effective vaccines (one by Pfizer-BioNTech, another by Moderna). The clinical trials for the two vaccines showed an astounding 90-95% effectiveness at preventing coronavirus disease and/or significantly curbing symptoms. However, even with two effective vaccines being rolled out, the fight for containment is long from over. There are issues with shortages, storage and distribution, and a whole lot of people who need to be vaccinated before we reach herd immunity.
As such, research and development for new vaccines is ongoing. Just this month, the Johnson and Johnson(“J&J”) company released promising interim clinical trial data on a brand-new vaccine (See Interim Results of a Phase 1-2a Trial of Ad26.COV2.S Covid-19 Vaccine).
This vaccine differs from those of Pfizer-BioNTech and Moderna in several respects. Most notably, the J&J vaccine is a single-dose vaccine. Both the Pfizer-BioNTech and Moderna vaccines require two doses to reach their full effectiveness. These two doses are separated by a period of about three weeks. J&J’s new vaccine will only require one dose. While there are still questions on effectiveness, the data published to date has been promising, showing that the vaccine was effective at producing a lasting immune response after a single-dose vaccination.
Further, in terms of side effects, the candidate vaccine was reported to be well tolerated by recipients. Side effects are the same or similar to other vaccines, including symptoms of fever and “fatigue, headache, myalgia and injection site pain” which “generally resolved within 24 hours” (See Article from Johnson & Johnson Website). Finally, equally exciting is the durability of the J&J vaccine, which can be stored for months with only refrigerator-range temperatures. This further distinguishes it from those of Pfizer-BioNTech and Moderna, which require freezing temperatures for short storage and extreme sub-zero degree temperatures for longer storage.
Again, it should be stressed that this early data is only interim clinical trial data. Regardless, more comprehensive data is on the way and could be published as early as February. If that is the case, and the results are as promising as the early data, J&J could be seeking FDA emergency use authorization by March or April. Of course, there are many factors to consider, including potential delays and questions on how effective the vaccine is compared to the other two we have so far. Regardless, this recent news is a welcome development in the fight to contain Covid-19, and could point to the release of a safe, effective single-dose vaccine by the summer—if not before.