AS the world looks to pharmaceutical companies to forge a way out of the Covid-19 pandemic, vaccine development has never experienced such limelight.
With a significant number of Covid-19 vaccine candidates well into phase 3 clinical trials, you may be wondering what panacea to expect.
How quickly will these vaccines provide protection, how many lives will be spared, and will this allow us to return to our pre-pandemic lives?
But a recent feature may provide a sharp wake-up call to our post-pandemic dreams, highlighting precisely what these trials do and do not set out to answer.
The researcher points to the dichotomy between how the world may perceive the purpose of the Covid-19 vaccine candidates and what the clinical trials that will put them to the test are designed to do.
None of the trials currently underway are designed to detect a reduction in any serious outcome such as hospital admissions, use of intensive care, or deaths. Nor are the vaccines being studied to determine whether they can interrupt transmission of the virus.
The researcher provides a handy table that includes a number of the leading vaccine candidates from companies such as Moderna, Pfizer, AstraZeneca, and Janssen.
The table provides data on the number of volunteers each company will recruit, their age ranges, and what outcomes, or endpoints, the companies will analyze to find out whether their vaccine candidate works or not.
All of the vaccine candidates that Dr. Doshi discusses are in phase 3 clinical trial and involve tens of thousands of study participants.
Yet the trials mostly exclude children, people living with conditions that compromise their immune system, and pregnant or breastfeeding people. This, in itself, is not unusual.
While a vaccine candidate is under investigation in clinical trials, some of the short- and long-term risks remain, to some extent, unknown. Protecting vulnerable groups in this way is standard and ethical practice.
Dr. Doshi’s table also gives an insight into how each company will measure how well their vaccine candidate performs. The technical term for the main criteria under investigation in any clinical study is “the primary endpoints.”
For the leading vaccine candidates, the primary endpoints focus on preventing symptomatic Covid-19 in the study volunteers. But there is a catch. While each company has its own definition of “symptomatic,” none of them are looking specifically at severe Covid-19.