How to develop a vaccine?
The research to control the spread of the COVD-19 pandemic has provoked all around the world an unprecedented race to develop a vaccine in record time, at the same time that hospital, pharmaceutical companies, public and private institutions work non-stop to find treatments to contain the effect of the coronavirus.
According to the World Health Organization, up to the present moment there are 70 vaccines against the coronavirus under development, what at first sight indicates an excessive competition that might jeopardize the international cooperation in getting to an effective solution in the shortest possible term, prioritizing the patient’s outcomes rather the one for the industry. The present status in which each country support its own trials coupled with some measures taken by some of these countries bring up the question if once a vaccine is developed that it will quickly reach other countries at a reasonable and accessible price, a haunting situation, when we bear in mind that millions of lives are at play.
Up until now people in general has never questioned how a vaccine or new medicine is developed, but with the unrelenting effort to contain this pandemic, for the first time the issue has reached the cover of the magazines. We’ll summarize it here below.
On a “standard” process, the development of a vaccine takes years, while at the present case time is a crucial factor. The complexity to develop a vaccine is high under normal situation, and at this moment, with an unknown pathogen, even more.
Phase 1: Exploratory stage
The first step to create a vaccine is to discover the pathogen in question – virus, bacteria or parasite. It is all about getting to know the biology of the pathogen in detail, since the structure of its proteins and the clinical characteristics of the disease have a decisive impact in the effectiveness of the vaccine. Subsequently, it is critical to properly select the antigen or antigens that have to be included to the vaccine so that, once inoculated in the body it has to be able to generate an immunologic response, and therefore, to guarantee immunity when exposed to the virus.
Phase 2: Pre-clinical stage
The preclinical studies use tissues or cell cultivation techniques and animal testing to evaluate the safety of the candidate vaccine and its efficiency in provoking an immunologic response. This phase offers cell reactions that could occur in humans, also capturing information about initial dosage safety and safe methods for vaccine inoculation. A whole number of vaccines do not beyond this stage, as they to not generate the expected immunologic response.
Phase 3: The clinical trials stage
Once phase two is completed, clinical trials with humans will begin. It starts with a small group of healthy volunteers – phase 1 trials – that will allow to evaluate the safety of the candidate vaccine and determine the type and reach of the immunologic response that is provoked by the vaccine. As this phase is completed, a larger sample of volunteers is added – phase 2 trials – with individuals that might be among the group of people at risk. The objective of this phase is to evaluate the safety of the vaccine, its immunologic capacity, the proposed dosage, the vaccination program, and inoculation method. The candidate vaccines that are successful on phase 2 progress to larger trials, involving thousands of people - phase 3 trials. The objective is to evaluate the safety of the candidate vaccine in a large group of people, as some not usual side effects might not be detectable on the smaller groups that were part of the previous phases.
Approval and regulatory authorization
If phase 3 trials are successful, the official forms are produced to obtain the approval and regulatory authorization that will allow to bring the vaccine to the public without risk and guaranteeing the effectiveness for the pathogen for which it was created.
Each of those steps is complex and requires a lot of time and supervision of the regulatory bodies to guarantee that all the steps and tenors are respected. Any small misstep in each of those steps might imply years of dedication and financial resources being lost.
Under the present circumstances, the complexity of this process clearly indicates that in this obstacle race we should cooperate in order to obtain the expected result in the shortest possible timeframe.
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