Considerations to accelerating and maximize the preclinical studies to a safe and effective COVID-19 vaccine

The emergence of novel coronavirus-2019 (COVID-19) by Severe Acute Respiratory Syndrome Coronavirus 2 (SARSCoV-2) virus and its rapid spread across the world have triggered a global health emergency without preceding. From the fi rst report of COVID-19 at Wuhan city of China in December 2019 until today there has been an outbreak of COVID-19 around the world, with 97, 831, 595 confi rmed cases and 2, 120, 877 death cases [1,2] and this number keeps growing.


Introduction
The emergence of novel coronavirus-2019  by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) virus and its rapid spread across the world have triggered a global health emergency without preceding. From the fi rst report of COVID-19 at Wuhan city of China in December 2019 until today there has been an outbreak of COVID-19 around the world, with 97, 831, 595 confi rmed cases and 2, 120, 877 death cases [1,2] and this number keeps growing.
Do not exist yet an effective drug is found for treating COVID-19 and a specifi c vaccine is the most promising hope. Therefore, intensive researches are urgently needed to speed up preclinical and clinical stages of the vaccines candidates, with the idea to provide some considerations to accelerating and maximizing the preclinical studies to a safe and effective COVID-19 vaccine, go this preclinical elements to share.
To achieve this aim, it is necessary to establish regulatory

How would it be possible to accelerate the development of a vaccine from years to months?
First has been the current context of the pandemic caused by COVID-19 that has allowed a redirection and a new approach to use both known drugs and non-specifi c vaccines against SARS-CoV-2 to try to stop this disease. for use in humans [11,12]. In this sense, the general principle that biopharmaceuticals that are pharmacologically similar to a product for which there is extensive clinical experience, may require only a complementary non-clinical toxicological evaluation, is supported not only by the position papers of the WHO, ICMRA and FDA, due to the current epidemiological situation caused by COVID-19, but also in the 2001 ICH/S7A guide for preclinical evaluation of biopharmaceuticals [13].

Optimize experiments to get more early safety information
Finally, it is possible not only to accelerate the development of vaccine candidates against COVID-19, but it is also possible to maximize the evidence of effi cacy and non-clinical safety from the fi rst trial in animal models [14][15][16]. For this, the experimental design is key, where in most of the studies carried out in animals, not all the possible information is obtained, the historical tendency has been to answer one, two or three questions, in one or more animal models, eg.: immune response, dose levels, immunization schemes, protection, among others.
However, even knowing that the fi rst experiments are based on formulations carried out at the laboratory level, under Good Laboratory Practice (GLP) and that these are not Good Manufacture Practice (GMP) prepared. In these "basic" studies can be assess in parallel, early elements of toxicity in immunogenicity schemes carried out in animals as safety criteria. The parameters to evaluate toxicity can be, the observation of clinical signs, the behavior of the body weight, the consumption of water, food, the body temperature, the local response to the administration of the product and macroscopic evaluation (necropsy). These parameters will make it possible to demonstrate the safety of the vaccine candidate with predictive value not only towards the toxicological studies themselves, but also towards the entire strategic projection of the product. Summary, it is possible not only to accelerate non-clinical studies, maximize vaccine responses, but also reduce evaluation time from years to months.