AstraZeneca tests drugs that can give instant immunity to coronavirus – 12/26/2020

Scientists from the United Kingdom and the United States are in the final phase of testing a drug that can give instant immunity to the coronavirus, thus preventing a person who has had recent contact with someone infected from developing the disease.

The drug, created by the pharmaceutical company AstraZeneca and called AZD7442, is a combination of two monoclonal antibodies, made in the laboratory from antibodies from people who have recovered from COVID-19.

The idea is to evaluate the action of the drug in people who have had recent exposure to the virus, but have not yet developed symptoms. The drug would prevent the disease from manifesting itself by fighting the viral action from the beginning, acting as a post-exposure prophylaxis.

Another research protocol of the pharmaceutical company aims to test the drug in people who have not yet had contact with the virus, so that its preventive action can be investigated.

In both cases, the drug targets the spike protein of the virus, responsible for its entry into the human cell. “The SARS-CoV-2 spike protein contains the RBD (receptor-binding domain) of the virus, which allows the virus to bind to receptors on human cells. By targeting this region of the virus spike protein, Antibodies can block the connection of the virus to human cells and, therefore, it is expected that they block the infection ”, explains the pharmacist in the study protocols registered on the website Clinicaltrials.gov, a clinical research platform of the US government.

The drug is in phase 3 clinical trials, but earlier stages of research have shown that this drug-conferred immunity would not be permanent – it would last six to 12 months, according to AstraZeneca.

Also according to the research protocols, phase 3 of the tests (the last before the drug was registered) began in November, (for cases of people without previous exposure) and December (in patients who were exposed to the pathogen ). Together, the two studies will involve about 6,000 volunteers.

If the drug has proven its effectiveness, it would be especially useful in situations such as older people living in long-term institutions who have had contact with a positive case in the middle. They could receive the medicine before the virus began to cause harm.

According to a report in a British newspaper The Guardian, the antibodies being tested are given in two doses and could be used up to eight days after exposure to the virus. UK scientists told the newspaper that they believe the drug will be available on the market between March and April if it proves its efficacy and safety in clinical trials.