Vaccinate everyone against corona in the short term? Forget it!

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Making a corona vaccine is tricky, but ensuring everyone gets the vaccine in the short term is practically impossible.

According to the latest data from the World Health Organization, 166 corona vaccines are currently in development. 25 of these vaccines are already undergoing clinical research, meaning they are being tested on humans. And some of those clinical studies have already shown promising results. For example, the vaccine ordered by the Netherlands, developed at Oxford University, has been shown to elicit a potent and two-fold immune response. And an American and Chinese vaccine also seem to make people produce antibodies against SARS-CoV-2 and thus offer some protection against the virus that is still in full swing.

Lavish press releases
The encouraging results led to exuberant press releases, rising stock prices of involved pharmaceutical companies and high expectations: a safe and effective corona vaccine appears to be up for grabs.

And yes, several pharmaceutical companies have already announced that they are expected to deliver the first proven safe and effective vaccines at the end of this year or at the beginning of next year. It seems a bit optimistic, especially since all vaccines have yet to go through the third – and most time-consuming – stage of clinical research (see box).

Extensive testing is required to demonstrate that a corona vaccine is safe and effective. Initially on animals. but later also on people. The latter occurs during so-called clinical research, which has three phases. In the first phase, a small group – often several tens of people – is given the vaccine and the optimal dose is examined, whether people experience side effects and whether they start producing antibodies against SARS-CoV-2 in response to the vaccine. . In the second phase, the safety and effectiveness of the vaccine is tested in a similar way among a larger group of people. In the subsequent third stage, the vaccine is administered to an even larger group of people. And again we look at whether the vaccine is safe and effective. But this time, not only must it be demonstrated that people produce antibodies against the virus, but also that the vaccine can actually prevent the virus from infecting and / or making people seriously ill. During this phase of the study, a large group of people – often tens of thousands of test subjects – will be divided in two, after which one group will receive the vaccine and the other a placebo. These people are then sent home. And after a while it must become clear whether SARS-CoV-2 actually occurs less among the group that has been vaccinated. It is a robust experiment. But you can imagine that the experiment takes a lot of time. After all, you should actually wait for test subjects to come into contact with the virus. And for the sake of goodness, quite a few of the subjects need to be exposed to the pathogen if you want to demonstrate convincingly that there is a significant difference between the frequency of the disease among the vaccine-vaccinated and the placebo-vaccinated groups. There is a way to accelerate this phase of clinical research. Instead of sitting down until a large proportion of the subjects are exposed to SARS-CoV-2 in daily life, you can also intentionally infect them with the virus. But that approach is not undisputed.

Only after the third phase of clinical research do we know whether a vaccine really protects against SARS-CoV-2 in everyday life. And it does not seem inconceivable that some vaccines that seemed promising in the first or second phase of the clinical research are not as effective in the third phase as hoped and one has to go back to the drawing board. So – regardless of the cries of pharmaceutical companies – it is far from self-evident that there will be a corona vaccine at the end of this year or the beginning of next year. The Dutch government also realizes this: “The risk of failure is present in each of the development phases until the end,” the Ministry of Health stated in the press release in which it announced the purchase of the Oxford vaccine, but also announced to keep looking at other promising vaccines.

Vaccine is coming
It seems almost certain that, in view of the countless vaccines that are being worked on, that a corona vaccine will eventually become available – either in a few months or a little longer. However, it does not seem plausible that the moment when the first vaccines will come onto the market is also the moment when this corona crisis comes to an end. Because not only developing and testing a corona vaccine is a huge challenge; making sure everyone gets it is even more difficult.

Scaling up
As soon as there is a proven safe and effective vaccine, it must be produced on a large scale. And that is not so easy, says professor Nikolai Petrovsky, associated with Flinders University and research director at Vaxine Pty Ltd, which is also developing a corona vaccine. “Most candidate vaccines against COVID-19 have never been produced on a scale of more than several thousand doses. It is quite a challenge to start making hundreds of thousands of millions of doses. ” Not only technologically, but also cost-technically. “What is never actually talked about, but what can also cost some vaccine technologies, is the cost of the vaccine (the total costs incurred to develop, produce and deliver the vaccine, ed.) If it is not low enough to keep the vaccine affordable. ”

The idea that a working – and therefore expensive – vaccine will soon be available that cannot subsequently be produced on a large scale is not to the liking of the pharmaceutical industry. And so, in this exceptional time, some pharmaceutical companies are taking exceptional measures. They are already starting to scale up the production of their vaccines, before the vaccines have actually been proven to work. “This is how they ensure that if the study results support the effect of the vaccine, a large number of doses are immediately available,” said Paul Griffin, a University of Queensland expert on infectious diseases. “Obviously this is a huge investment and a huge gamble if it doesn’t work after the clinical studies, but it is the main way in which the vaccines can be made available more quickly.”

Fair sharing?
But even if companies manage to scale up quickly, not enough vaccines will roll off the assembly line right away. For example, Moderna, the American company behind the promising corona vaccine mRNA-1273, expects to be able to produce between 500 million and 1 billion doses next year. Impressive quantities, especially when you consider that the virus against which the vaccine has to protect us, was unknown to us a year ago. But it is not enough for everyone. No wonder countries are already rushing to reserve promising corona vaccines, thus trying to ensure that they can be the first to get a working vaccine and thus be the first to protect their populations from the virus and their economies to throw open. Wealthy countries have – as usual – an advantage, which means that countries with less financial resources risk being left empty-handed. “That is guaranteed to happen,” says Petrovsky. “How long did it take for Prevnar (a vaccine against various types of Streptococci, ed.) Or Gardasil (vaccine against the Human papillomavirus, ed.) To arrive in developing countries? And now, after almost twenty years, these vaccines are still being administered sparingly due to their artificially high prices. ”

“I would hope that parts of the world that most benefit from a vaccine get it first,” Griffin notes. But he immediately states that it is too idealistic. In practice it simply works differently. “The countries in which the vaccines have been developed naturally want to give their own residents access to the vaccines when proven to be effective. And the financiers also want to have a say in who gets the vaccine. ”

COVAX Facility
Rather, in an effort to make the vaccine available to everyone, the COVAX Facility established. Rich and poorer countries join forces within the initiative. They invest together in multiple vaccines – spreading the risks and costs – and once there is a vaccine that passes all tests with flying colors, it is shared fairly among all participating countries. Dozens of countries have already expressed interest in the initiative. But at the same time, there are also many countries – including the Netherlands – that sit around the table with vaccine developers on their own to ensure a vaccine. It is also called vaccine nationalism: countries have a strong idea that they have a duty to provide their own residents with a vaccine first. But we are only really safe if everyone has access to the vaccine. Until then, new outbreaks and lockdowns – with all the social and economic consequences – are looming. And people in a country that has managed to get their hands on a vaccine, but cannot be vaccinated due to other conditions, are not safe at this time of globalization. “No one is safe from COVID-19, as long as not everyone is safe,” humanitarian organizations regularly say for good reason.

Within national borders
But hard choices will not only be made on the world stage. Also within the borders of countries that are able to lay their hands on a vaccine, choices will have to be made in the first instance. Petrovsky can be brief about who should be given priority. “First, the people who work in healthcare. Then the people of old age. ” Griffin feels the same way, but also mentions people who fall into the risk group because of other health conditions.

Logistics
A fair distribution across the world and within national borders is also a huge challenge from a logistics perspective. Where rich countries have the resources and infrastructure to efficiently transport and distribute vaccines, it is often different for poorer countries. Even more complicated, both the transport and storage of vaccines are such as these – like some of the candidate vaccines against SARS-CoV-2 – that have to be stored at very low temperatures (around -60 degrees Celsius). It requires refrigerated transport and refrigerations in which the vaccine can be stored once on arrival. And that can sometimes be problematic in Africa; for example, only 28% of health care institutions in Sub-Saharan Africa have access to a reliable electricity network. It is also questionable how people who live in remote areas and who do not have a hospital or healthcare institution nearby will receive this vaccine. How difficult it all is in practice becomes clear when we look at the current vaccination programs that have been set up worldwide and are aimed at children. Although governments and organizations such as the WHO have been making efforts to vaccinate every child for decades, 1 in 5 children still miss the basic vaccines. It does indicate how difficult it will be to offer every individual on Earth the opportunity to be vaccinated against SARS-CoV-2.

It is certain that a vaccine is the only way to leave this corona time behind. But no vaccine – no matter how effective – can turn the tide in one fell swoop. Instead, vaccinating the world’s population will be a gradual process. The hopefully imminent announcement of a proven effective and safe corona vaccine is therefore in itself no reason to claim victory. But only the beginning of a completely new and unparalleled challenge: to ensure that the vaccine, after the virus, reaches all parts of the world.

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