The excitement is palpable as the first two SARS-CoV-2 vaccine candidates enter the homestretch for Food and Drug Administration licensure.
As approval grows nearer, a vocal minority has stated they will refuse any vaccine that shortcut the regular testing process. Given that it usually takes a decade to develop, test and license a vaccine, it’s important to understand how the process is being accelerated.
Firstly, the vaccine companies are not starting from scratch. Although considered “new,” these technologies have been studied for at least a decade as vaccines and cancer therapies. So far, they’ve been found safe.
Keep in mind that these technologies were specifically developed, so vaccines could be rapidly produced in the face of an emerging infectious disease — exactly our present situation.
The federal government has given vaccine development the highest priority and opened its pocketbook to facilitate research. Ordinarily fiscally cautious, companies have given priority to their SARS-CoV-2 candidates without fear of financial loss.
Additionally, the FDA, U.S. Centers for Disease Control and Prevention, National Institutes of Health and other governmental agencies have given SARS-CoV-2 vaccine research precedence over other research. The candidate vaccines are moved to the front of their work queue.
Federal funding has allowed a huge increase in the number of people working on all aspects of vaccine development. Similar to digging a ditch, the more workers, the faster it goes.
The vaccine companies and government have hired or contracted for more staff at all levels. This allows for the rapid execution of contracts, shipping of supplies, set up of research sites and so on.
Unique to this situation, the phases of human trials are running to a certain degree in parallel to shorten the time from the beginning of phase 1 to completion of phase 3. Typically, the complete data from phase 1 is required to start phase 2 and phase 2 must be finished before beginning phase 3.
The initial data from phase 1 studies are used to launch phase 2 and the phase 3 studies are being initiated based on early data from the phase 2 studies.
This does minimally increase the risk for research volunteers but is justifiable given the severity of the pandemic. As with all human trials, volunteers are informed of the risks. Volunteers in vaccine trials are truly heroes.
Finally, the planned number of volunteers for later phase studies are double the usual to quickly evaluate safety and effectiveness. For example, 30,000 volunteers will be enrolled in each phase 3 study.
The rub is effective candidates will be licensed before long-term data is available. Primarily, we will not know how long protection lasts and what happens if vaccine effectiveness wanes. It may be that people will need booster vaccinations or perhaps even vaccination with another type of SARS-CoV-2 vaccine.
Given all this, people will have to weigh their options to avoid SARS-CoV2: staying home practicing social distancing or vaccination. We bet most will chose immediate vaccination instead of waiting a couple years for all the long-term data to be collected.
Vaccine Smarts is written by Sealy Institute for Vaccine Sciences faculty members Drs. Megan Berman, an associate professor of internal medicine, and Richard Rupp, a professor of pediatrics at the University of Texas Medical Branch. For questions about vaccines, email firstname.lastname@example.org.