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The LSE’s professor of health policy, Elias Mosialos, reports on the latest developments regarding coronavirus vaccines, and estimates that the first vaccines may not be more than 50% effective.
According to the government representative for the pandemic in international organizations, of the more than 300 candidate vaccines, 11 are in the final phase.
Given the limited effectiveness, it will be necessary to purchase different types of vaccines, as a vaccine “may not be effective for some groups, but it may be very effective for others,” he said.
According to Mosialos, “the predictions of scientists on when the analysis of the effectiveness of the first vaccines will begin after the completion of phase III range from the next 2-3 months, until mid-2021,” while listing in detail the stage where there are the vaccines that have entered the final phase.
In any case, as he points out, the fight against the pandemic is combined with five parameters: implementation by the State and companies, measures against the spread of the virus, implementation of public health regulations by citizens, the use of drugs, the first generation. vaccines and the second and probably most effective generation of coronavirus vaccines. 
Elias Mosialos’ post in detail:
Just before the end of September there are more than 300 candidate vaccines for COVID-19, 42 of which are being tested in humans and 11 are in the final phase, phase III, of clinical trials.
How do vaccines work?
Vaccines are based on the ability on the one hand to stimulate and on the other hand the memory of our immune system. That is, we stimulate the body to produce its own antibodies against Sars-Cov-2, so that a series of reactions are activated and the virus is fought. When the virus enters the body in the future, either the antibodies that already exist or the memory cells will initiate the necessary neutralizing actions so that we do not get sick.
What types of coronavirus vaccines are being tested in clinical trials?
There are many approaches that can be used, some more classic and some more innovative, and researchers around the world have already incorporated them into the design of coronavirus vaccines.
With a “classic” vaccine we can introduce the virus into our body, but inactivated (that is, the virus has been “killed”, for example, by heat or chemicals).
We can also introduce a part of the virus into our body, which is different from related viruses. Viruses enter human cells and use them as a laboratory to make the parts they need one by one, so that they can eventually multiply and take their functional form. One of those structural components, in the case of the new coronavirus, is the spike protein. Researchers have developed vaccines that give our cells the ‘recipe’, the genetic information, to make parts of the coronavirus, for example the pin. 
These vaccines can be:
- contain common modified viruses that cause coughs or colds. When we make the vaccine, these viruses will make the spike protein that the coronavirus uses to attach itself to healthy human cells.
- They are mRNA and DNA vaccines, as they are called, that will introduce the ‘recipe’ into our cells so that our cells can make the protein increase
- They are fragments of the peak protein but without the genetic information.
In each of these approaches, the goal is for our body to respond by producing antibodies against this spike protein.
Of the 42 vaccines in clinical trials or already licensed for limited use in some countries:
- 6 are inactivated virus containing vaccines (such as Sinovac and 2 Sinopharm vaccines, all licensed for restricted use.
- 8 are vaccines based on a viral vector (such as Russian vaccine, Chinese CanSino vaccine, and AstraZeneca vaccine)
- 11 are mRNA-DNA vaccines (like Moderna and Pfizer)
- 17 are protein vaccines (such as Novarax phase III)
So when can we expect results?
Scientists’ predictions of when the analysis of the effectiveness of the first vaccines will begin after the completion of phase III range from the next 2-3 months, to mid-2021:
- Pfizer / BioNTech said it would have enough Phase III data to begin analysis by the end of October.
- Moderna, which already has more than 25,000 participants in this phase of clinical trials and more than 10,000 have received both doses of the vaccine, said last week that an interim analysis of the test results is likely to begin in November and possibly to At the end of December.
- AstraZeneca believes that before the end of the year it will be close to presenting the approval regulations. About 18,000 people in the United Kingdom, United States, South Africa, and Brazil have received the AZD1222 vaccine to date. But clinical trials in the United States for the AstraZeneca vaccine have stopped and these estimates may be overly optimistic.
As I mentioned recently, in clinical trials, those who get the vaccine don’t get the disease at the same time. Clinical trials have focused on demonstrating the safety and efficacy of the vaccine. Both are evidenced by the immune response of the volunteers. After vaccination, we actually wait for the volunteers to be exposed to the virus and see if the vaccine protects them. However, this process can take several months, as many vaccinated volunteers may never contract the disease. Especially in a pandemic situation where we try measures to stop the dynamics of the spread and isolate carriers and patients.
Despite announcements and statements from company executives, Pfizer and Moderna’s Phase III clinical protocols make it very clear that they won’t know if their vaccines work until December / January at the earliest. However, if we look at the clinical trial protocol, we see that this estimate is not certain.
- In the case of Pfizer, 164 of those vaccinated against the coronavirus will wait to be exposed to real efficacy. An independent review committee will also review the data in 62, 92, and 120 cases.
- In Moderna’s case, the evaluation will take place after 151 of the vaccinated people have been exposed to the virus and the independent commission will examine the data after the first 53 and after the 106 cases.
It also matters how much and when these vaccinated people were infected. These figures may seem small, but I remind you that in England, where studies of causes of disease will be carried out, they are aimed at a deliberate infection of 100-200 volunteers. The committee, and then regulators, must trust that the analysis will continue into the next months or years of the study, where more participants could become ill.
Pfizer’s clinical trial has surpassed 30,000 volunteers and more than 12,000 have received the second of the two doses, three weeks apart. Pfizer’s clinical trial begins measuring COVID-19 infection cases 7 days after the second dose. Moderna takes the second dose 4 weeks after the first dose and the analysis of the cases that will be exposed begins two weeks after the second dose (around 10,000 of the more than 25,000 volunteers are reported to have taken the second dose). Remember that the FDA Advisory Committee on the course and criteria for evaluating vaccines will also convene on 10/22.
In conclusion: the discussion about coronavirus vaccines has 3 components:
- The variety of approaches used by researchers
- The Impressive Growth Rate of New Vaccines
- The dependence of the world community on the approval of vaccines given the lack of drugs so far, in addition to dexamethasone which significantly reduces mortality.
I often say that we have to await the results of the evaluation of clinical trials, the importance of evaluation by independent and international regulators, and transparency in the announcement of results. Why do I mean posts and developments with moderate optimism and realistic time demands?
Once the results of the phase III clinical trial have been evaluated, the competent regulatory authority could approve a successful vaccine that allows the vaccine to be delivered early to vulnerable groups. It will probably take an additional six months to perform a second phase III analysis of the data before the vaccines can be made available for larger public vaccination campaigns.
Previous research on coronavirus vaccines has also identified some challenges to COVID-19 vaccine development, such as providing long-term protection, as well as protection for the elderly and those taking immunosuppressive medications or those with a reduced immune response. . These groups are at higher risk of developing severe COVID-19. However, we know that older people generally do not respond to vaccines as well as younger people and may need booster doses. An ideal COVID-19 vaccine would work well for both the vulnerable and this age group.
It is highly unlikely that any of the early vaccines will be 100% effective. Regulators have set 50% efficiency as the criteria for vaccine approval. At 50% efficiency, it is doubtful that we will achieve herd immunity even if the entire population is vaccinated, which is also extremely doubtful. But a vaccine even 50% effective will go a long way in the fight against coronavirus.
Therefore, it will be imperative that we continue to implement public health protection measures after the discovery of new vaccines, until we can significantly reduce the spread of the virus, both globally and in our country.
Finally, while it is unlikely that we will have a vaccine that is more than 50% effective, the fact that we have many types of vaccines, as I explained, can have beneficial effects. Simply put, a vaccine may not be effective for some groups, but it may be very effective for others. This will require the supply of different types of vaccines. 
The final treatment of the coronavirus will come from a combination of 5 parameters:
1. Implementation by the State and companies of measures against the spread of the virus: frequent transport, improvement of telework, frequent ventilation measures with fresh air indoors (for example, in schools and workplaces), strengthening of the ANS , direct monitoring and isolation of patients and more frequent use of diagnostic tests, an interdisciplinary approach to monitoring the pandemic and the establishment of a working group (with the participation of specialists and experts from multiple and not just medical specialties) to design alternative approaches to treat our country and internationally.
2. Application of public health standards by citizens
3. Use of medications (dexamethasone and possibly in the next few months and antibody treatments)
4. First generation of vaccines against coronavirus
5. Second generation, probably more effective, of vaccines against coronavirus.
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