On November 9, we saw some of the most positive news regarding Coronavirus: the development of an effective vaccine. But what does this mean for the pandemic?
Pfizer and the German partner company, BioNTech, collectively announced the development of a vaccine that has proved 90% effective in clinical trials. This is well above the 60% effectiveness medical experts expected and were willing to green light for distribution. The first set of clinical trials was conducted on a test group of 44 000 adult individuals in several countries. For a 90% effective result, nearly all of the infections that occurred in the trial would have had to be in the placebo group. Pfizer has not released any explicit breakdowns of the trial results; however they have stated that the protection rate may change as more COVID cases are added to the calculations.
While the vaccine looks promising, there are still many questions that have yet to be answered. These include how long the vaccine effects last, whether it protects children and aging populations beyond just the adult population, and its effectiveness on racial minorities. An external panel of experts raised these questions during the vaccine’s first formal review, from which the original announcement by Pfizer and BioNTech was based. This panel, however, also acknowledged the need to publicize the actual data from the Pfizer trial, as well as longer-term results.
BioNTech began developing the vaccine in late January, using a technology which had never before been used on human subjects. The technology takes RNA, a genetic messenger within cells, and injects it into muscle tissue. The muscle cells treat the RNA as a recipe for building a protein, a protein found on the surface of COVID-19 itself. These proteins, in turn, stimulate the immune system, which is believed to build a long lasting immunoprotection from the virus.
BioNTech quickly discovered 20 vaccine candidates from this technology, and began preliminary tests of these on rodents. In March, BioNTech reached out to partner with Pfizer, to compensate for the former’s lack of experience and resources for fast mass clinical trials. Early human trials indicated two potential vaccine strains that proved to be particularly robust. These two candidates triggered antibodies against the virus, as well as specialized T cells, a powerful type of immune cell. The candidate with fewest side effects was green lit for mass clinical trial, which was conducted with 44 000 participants from the US, Argentina, Brazil, and Germany. Pfizer and BioNTech are both aware that the FDA is skeptical of data from such small trials, but are hopeful that with the rapid spread of the virus, the FDA will approve the vaccine for general distribution after a pre-scheduled second analysis.
The vaccine consists of a two dose schedule with a second injection being administered approximately two weeks after the first. It also has other logistical challenges. A key ingredient in the vaccine is mRNA, which needs to be stored at very cold temperatures, -70 to -80⁰C. This is raising questions about transportation and storage, especially to majority countries that may not have the capacity to transport, let alone store, a vaccine which requires cold storage. In minority countries, distribution will be a challenge as many medical storage centers only go down to about -15⁰C, and even in well populated cities finding storage facilities for millions of doses is going to be a challenge. As things stand, Pfizer has struck vaccine deals (accepted orders) exclusively from rich countries. The danger therein being that, beyond inequitable distribution, if over half of the world’s population is left unvaccinated, COVID-19 will continue to bounce back and mutate into new strains; which could prolong the pandemic for several years. Ultimately, the vaccine at this stage is good news for middle aged white people in the northern hemisphere cities, and only for the short term.
The vaccine could begin distribution in as little as seven weeks, but don’t expect to receive it anytime soon. Germany, France, and the UK are on schedule to receive about 50 million doses in January. The administration of the vaccine will be staggered, with the most vulnerable populations receiving it first; these include aging populations and essential workers. Canada has ordered 10 million doses, which will also be administered in a similarly staggered fashion. How that will look is a little more uncertain. Canada does not have a rollout plan for any COVID-19 vaccine, despite likely receiving the ordered doses by spring or summer of 2021.
While Pfizer and BioNTech’s announcement has provided a much needed glimmer of hope at the end of the dark and spiraling tunnel that has been 2020, there are still many questions and logistical issues that need to be addressed before widespread celebration of the end of the pandemic can really begin.