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The chances of a corona vaccine soon appear to be increasing. Several active ingredients are already in the crucial final testing phase. But the reverse at AstraZeneca proves: Nothing is certain yet.
Never before have so many people around the world looked at science with hope: since the beginning of Corona-Pandemie Researchers and pharmaceutical companies seek a vaccine against the coronavirus SARS-CoV-2, there are new success stories regularly.
According to the Association of Pharmaceutical Research Companies (vfa), there are currently at least 184 vaccine projects for SARS-CoV-2. 37 companies and institutes are currently testing their potential drugs in clinical studies with volunteers (as of September 3, 2020), and at an unprecedented speed: several active ingredients have already moved to the crucial final phase of volunteer testing.
Serious side effect? AstraZeneca stops study
However, with all progress there can always be setbacks. This can be seen today in one of the highest hopes in vaccine development to date: During the final phase of crucial testing of a drug candidate from British pharmaceutical company AstraZeneca, health problems occurred in one of the participants of the study. The study was stopped as a precaution.
But what is the current status of AstraZeneca and other competitors already in the crucial study phase? We present the projects and explain the different stages up to the approval of a vaccine.
The Covid-19 Vaccine Was Developed: Why This Puncture Raises High Hope. (Source: Reuters)
Various stages of testing up to the approval process
The AstraZeneca incident shows how important it is, despite all the urgency, to test active ingredients in detailed studies. An active ingredient must have successfully passed several stages before it can be approved:
After efficacy and tolerability were first tested in animals, then they were tested in the first clinical phase in a small group of test people and in the second phase they were examined in a larger group of 50 to 500 volunteers for determine tolerance, dose and type of immune response, the third follows Test step:
Here’s the potential vaccine tested on a group of several thousand test people to determine the reliability of protection and possible rare side effects.
Pharmaceutical companies promise security in development
If the vaccine candidate proves their worth, an approval process can be started. And in some countries of the world this is now practically possible on the fast track.
However, in early September, the nine pharmaceutical companies AstraZeneca, GlaxoSmithKline, Johnson & Johnson, Merck & Co., Moderna, Novavax, Sanofi, Biontech and their US partner achieved Pfizer in a statement that safety and efficacy in the development of a corona vaccine are the highest priority.
Interrupted Study: University of Oxford with AstraZeneca
In July, the British University of Oxford announced encouraging news: Its vaccine candidate had shown promising results when tested in 1,077 healthy volunteers. The first testing phase with the active ingredient started in the UK at the end of April. Since the end of June it has been tested in phase three in Great Britain, Brazil, South Africa and the United States.
AstraZeneca is involved in the development of the vector virus vaccine, which uses a weakened version of the common cold virus found in chimpanzees. The Swedish-British pharmaceutical company planned to start producing a vaccine by the end of the year. The sale price per dose should be only 2.50 euros, according to the head of the group, Pascal Soriot.
How Vector Virus Vaccines Work
Other more harmless viruses, such as the vaccinia virus or a weakened vaccine strain of the measles virus, serve as the basis for these vaccines. These viruses are equipped with components of the new coronavirus SARS-CoV-2. Ideally, the human immune system reacts to this harmless virus, disguised as SARS-CoV-2, by producing antibodies against the new coronavirus.
Now AstraZeneca suffers a setback: Because one study participant became ill during advanced testing, the group had to interrupt their study of the corona vaccine for now. According to a New York Times report, which quotes an informed person, the health problem is inflammation of the spinal cord, which can be caused by viruses. It is not yet clear if it is really related to the vaccine. AstraZeneca said this now needs to be independently verified.
Meanwhile, other vaccine projects around the world are testing their drug candidates in phase three studies:
First phase 3 study in Germany: Biontech and Pfizer
Mainz-based Biontech is researching a gene-based vaccine together with the US pharmaceutical company Pfizer. The first clinical trials in volunteers began in Germany in late April and a phase two / three study began in the United States in late July.
The tests in the third phase of testing in Germany were approved by the Paul Ehrlich Institute in early September. According to Biontech CEO Ugur Sahin, the integration of study centers in Europe, and now also in Germany, should support local approval. If the current clinical trial of their potential corona vaccine is successful, Biontech and Pfizer aim to apply for marketing authorization in October.
This is how gene-based mRNA technology works
MRNA (in English: messenger RNA) is a natural messenger substance that stimulates human cells to activate their own defense mechanisms against a certain pathogen. For this purpose, the mRNA is equipped with information about a coronavirus protein and is smuggled into human cells. The human body then recognizes the protein produced by its own cells as foreign and activates its immune cells. These produce antibodies and T cells against the virus: the body’s own defense mechanism builds up, just like a natural infection with the virus.
One of two candidates: Beijing Institute of Biological Products / Sinopharm
The Beijing Institute of Biologicals is investigating a killed vaccine that works on viruses killed by Sinopharm. A phase three study is currently underway at its own facilities.
The state-owned China National Pharmaceutical Group (Sinopharm) is testing two COVID-19 vaccine candidates in humans and announced in early July that it had completed construction of a new coronavirus vaccine facility in Wuhan. This is intended to complement the facility in Beijing, the construction of which was completed in April.
This is how killed vaccines work
The variant of vaccination it is based on inactivated pathogens and can work in two ways: they contain certain viral proteins or all material from inactivated SARS-CoV-2 viruses. Vaccines against flu, measles, or hepatitis B are also designed this way.
Wuhan / Sinopharm Institute of Virology: Successes in the last phase of testing
A second potential anti-active ingredient is also well advanced in human clinical trials. COVID-19 by Sinopharm, which is being developed jointly with the Wuhan Institute of Virology. The Chinese state-owned biotech group Sinopharm started the phase three study in the United Arab Emirates with 15,000 volunteers in mid-July, and trials are also underway in the last of the clinical phases in China and Bahrain.
The vaccine is inactivated, so it is dependent on killed pathogens. These are recognized by the body as foreign and stimulate the body’s own defense system, so they are antibodies and are important for defense. T cells They are formed.
Modern: in the last phase since July
Some time ago, the American company Moderna announced promising interim results for its candidate gene-based vaccine called mRNA-1273. Moderna began the first phase of volunteer testing in the US in mid-March. According to the biotech company, the participants became immune to SARS-CoV-2 after two vaccinations.
In animal experiments with mice, vaccination with mRNA-1273 also prevented the pathogen from multiplying in the lungs. A phase three study began on July 27 in the United States.
Sinovac Biotech
The Chinese company is investigating a potential active ingredient against Covid-19 called CoronaVac. Work with inactivated virus.
A phase three study was approved in Bangladesh starting in August. 4,200 volunteers will participate in trials in the densely populated South Asian country.
After advance approval: Russia continues to test “Sputnik V”
The approval in Russia on August 11 caused a stir around the world: the Gamaleya National Research Center for Epidemiology and Microbiology in Russia is working on a vector virus vaccine called “Sputnik V” A dozen of themes.
The third testing phase only started on September 9 in the Russian capital Moscow, about a month after approval. The drug was injected into the first volunteers, said Deputy Mayor Anastassija Rakowa in Moscow, according to the Interfax agency. A total of 40,000 volunteers across the country will be vaccinated and then undergo medical observation for six months. However, according to the authorities, Russia wants to vaccinate the first parts of the population, first teachers and doctors, before the end of the study.
