In the last few days it seems that important steps have been taken towards a vaccine for Coronavirus. Are we really approaching the moment when we will (finally) defeat COVID-19?
The pharmaceutical company Pfizer, together with BioNTech (on November 9th 2020) announced a 90% efficacy rate for their vaccine against SARS-CoV-2. A great result that followed just one week after that of another much lesser known pharmaceutical company, Moderna, which has the support of the US government. Moderna, announced an efficacy rate of 94.5% for the 30,000 patients tested during the Phase III clinical trial.
Normally, this process takes about ten years, sometimes even longer, with hundreds of millions of Euros being invested. But how did these two companies manage to reach Clinical Phase III so quickly?
Let’s start by explaining that this clinical phase is one in which the tests extend to a large number of people. Above all, it serves in determining how effective the drug is, which is also compared with other drugs currently on the market. It usually lasts months, with a monitoring period for side effects, lasting at least a few years.
The “secret” lies in the innovative technology used, mRNA
RNA and one of its products, mRNA, are less famous than DNA but equally important, since they’re fundamental in the make-up of proteins that form the basis of all organisms and many metabolic processes.
Vaccines developed by Pfizer and Moderna contain specific mRNA molecules that instruct cells to synthesize viral proteins, which are then recognized by the immune system that, in turn, produces antibodies accordingly, and is ready in case of attack by SARS-CoV-2.
Traditionally, instead, vaccines are produced from attenuated or inactivated viruses and more recently, thanks to molecular biology, techniques no longer from viruses but from very safe molecules.
The mRNA technology has allowed for the development of a vaccine much faster and the start of clinical trials just as quickly.
Are the two vaccines really effective?
It’s all still to be proven; sure, the data disclosed are encouraging, an effectiveness of 90% by the Pfizer-BioNTech vaccine tested on 60,000 people and 94.5% effectiveness by the Moderna vaccine, tested on 30,000 people. The tests were performed on homogeneous groups of people by age and sex who were separated into two groups: 50% received the vaccine and the other 50% a placebo (i.e. a saline-based injection).
Returning to effectiveness, it seems that Moderna’s vaccine is particularly effective in the elderly population, which is also the most fragile and exposed.
There’s still room for doubt
Actually, there are still several questions to which we still have no answer:
- How long will people remain protected with vaccination?
- Will the vaccination completely block the infection or will you only have less serious symptoms, especially in people with other diseases?
- In case a vaccinated person contracted the virus anyway (this is the case, for example, of that 10% of people on which the Pfizer-BioNTech virus seems not to be effective), could they still be less infectious?
What are the side effects being observed on volunteers who were vaccinated?
According to available data, both vaccines demonstrated no serious side effects. We don’t yet know the percentage of people who have shown side effects following the administration of the vaccine, but we do know the symptoms (e.g. fatigue, muscle pain, headache, moderate fever and pain at the injection site); all side effects already experienced as with many other vaccinations.
Unfortunately, the most reliable safety data will only be collected over time, and when a significant number of people are vaccinated.
Are there any other vaccines under clinical evaluation?
Fortunately, there are others. “Fortunately” because it’s important to have several choices; on one hand for scientific reasons, (i.e. based on vaccine-development technology, there may be more effective and less effective vaccines, especially on different population groups). On the other hand, for financial reasons; having only one company that produces the vaccine means that there is a lack of competition that can lower prices and stimulate higher quality.
At the moment there are another dozen pharmaceutical companies that are developing the vaccine against SARS-CoV-2 (read about them here). Most use mRNA technology but some use different approaches; in any case, all vaccines are directed toward the Spike protein of the virus and may be the key to enter human cells.
Is the glass half empty or half full?
In conclusion, thanks to the good news about vaccines and especially the adoption of different therapies, we’re beginning to see the light at the end of the tunnel.
The first doses of vaccine will be available soon (for a limited number of people); the mass availability will perhaps occur in late Spring or early Summer of 2021 and will be directed mainly to those places (e.g. United States, Europe, Japan and Canada) that have the economic strength to secure the necessary doses.
The rest of the world may not be so lucky, with the exception of China, which will make the vaccine itself; not surprisingly, CanSinoBio is one of the companies in the running but of which less is known.
Here’s a short video, demonstrating the mRNA technology.
This post is also available in: Italiano