The World Health Organization (WHO) assured this Thursday that what happened with the COVID-19 vaccine from the University of Oxford and the pharmaceutical company Astrazéneca, which had to stop the phase three clinical trials after a patient presented a serious side effect, is something common and that shows that safety is being prioritized.
The WHO chief scientist said it is possible that once the clinical trial monitoring team reviews the data on the individual who became ill, the trial could continue, but that would depend on the decision of the commission appointed for these. cases.
“Each clinical trial protocol has an operating procedure to manage these side effects. The clinicians doing the trials are trained in good practice, which means that they are closely following and monitoring all participants, and there is a protocol on what to do when something happens. If it is mild there are things that can be done. If it is severe, as it was in this case of a severe side effect, the trial was stopped. This is a normal procedure and is good practice, because safety is the priority in any clinical trial, ”explained Dr. Soumya Swaminathan.
Swaminathan said that this is a lesson to recognize the fact that there will always be ups and downs in clinical research and development.
“It is not always just a fast and straight path, but we cannot lose hope because this kind of thing happens … We have to wait to see the data of what really happened,” he added.
The expert recalled that, although of course the WHO wants to see good results, and “the faster the better”, It is a process that takes time and cannot be rushed since sufficient data must be collected from a certain number of people that are later analyzed and approved by regulatory entities.
“This requires tens of thousands of people to undergo the trial. If we look at the current ones, they have 30,000 to 60,000 participants. Usually half are given the vaccine and the other half a placebo. It is a blind study, so neither the patients nor the companies know to whom they gave what and those who receive the vaccine should be monitored for a minimum of six months to prove efficacy and safety, ”she explained.
Swaminathan said that with some of the trials starting in July, results are possible by the end of this year, although the safety follow-up should continue for longer.
“Regulatory agencies also they will need time to examine the results and make a decision on whether the vaccine is ready or not to be patented ”, he added.
The doctor stressed that right now there is no way to predict which will be the successful candidate vaccines, but that most have had promising data in phase 1 and 2.
“They have been able to generate an immune response in terms of neutralizing antibodies and also lymphocytes and safety has not been a problem in these small numbers, but in the end what we want to see is protection from infection and serious symptoms and for that we need to have the data from these large clinical trials in phase three. So we have to be patient and wait for the results ”, he concluded.
© UNICEF / Samir Karahoda
It is not a competition and you have to be patient
For his part, the WHO emergency director, Michael Ryan, said that, although he understands that there is a generalized anxiety to move as fast as possible, no vaccine can skip steps and that is why there are already designed protocols.
“The purpose of this is to make sure this is done in the most direct, honest and scientific way, which takes time. This is not a race, it is a race against the virus and to save lives, but it is not a race between companies, nor between countries, it is a race to support public health in the most effective and safe way possible, and in that race it is that we are, it is not a competition and many of the drug companies have said it publicly ”, he stressed.
The adviser to the director of the WHO, Bruce Aylard, also explained that, although the WHO provides the best scenarios when it comes to delivering a vaccine to countries, it must be understood that there are aspects that are out of the hands of the developers and scientists.
“For example, the time it takes to find volunteers who want to apply the vaccine in phase three clinical trials, it is tens of thousands that are needed, and that does not depend on the developers. There are other factors that must be taken into account, such as the time that regulatory entities may take, and that is whyor so right now there are different time ranges that are being predicted. What we have seen, with all the clinicians, is that we are not reaching the best possible deadlines right now, so by the end of this year and the beginning of the next we will be able to have a clearer idea, “he said.