By Lily Cao ’21
Staff Writer
As COVID-19 levels spike across the globe, many places around the world are heading into another round of lockdowns. Along with this growing second wave come announcements from companies working on possible coronavirus vaccinations.
On Nov. 9, American pharmaceutical corporation Pfizer Inc. and German biotechnology company BioNTech SE shared that their mRNA-based vaccine candidate, BNT162b2, has shown record-breaking early results with over 90 percent efficacy against COVID-19. This finding from Phase 3 of their clinical trial was the first interim efficacy analysis, which tests the vaccine’s effectiveness under ideal circumstances. The vaccine was given in two doses with results collected seven days after the second dose. Even though it is unclear how strong the elicited immune response is and how long it will last in human bodies, this achievement marks a milestone in the vaccine development process and provides hope for the days ahead.
Pfizer and BioNTech SE launched the Phase 3 clinical trial of their vaccine candidate on July 27. As of Nov. 9, they have enrolled 43,538 participants worldwide. This is also the first American trial to have permission to enroll children as young as age 12. On Nov. 8, 94 trial participants had tested positive for COVID-19, enough to allow for the first analysis on all cases.
According to its Nov. 9 press release, Pfizer plans to present a submission for Emergency Use Authorization to the FDA in the third week of November. The FDA requires the safety and manufacturing data of the vaccine to obtain approval. Meanwhile, in order to ensure the safety and long-term protection conferred by the experimental vaccine, clinical trial participants will be monitored for an additional two years after receiving the second dose.
One of the challenges the companies face is the widespread distribution of the vaccine once it is approved. The vaccine requires that the single-stranded mRNA be kept below -80 C to preserve the structural integrity of the genetic material. Consequently, the transportation of the vaccine requires special storage boxes and precise techniques.
Similar to Pfizer and BioNTech SE, Moderna Inc.’s vaccine candidate also uses mRNA technology, and recent results from its trial indicate an efficacy of over 94 percent. Moderna’s vaccine, however, does not require storage at temperatures of -80 C and can be preserved at about -20 C, giving it a slight advantage. At the same time, there are currently 17 vaccine candidates that have entered the Phase 2 safety trials, and 12 have begun Phase 3 trials for large-scale efficacy tests.
If Pfizer and BioNTech SE’s vaccine candidate is approved, the companies expect to manufacture globally up to 50 million doses in 2020 and up to 1.3 billion doses in 2021.