Why use pre-existing anti-COVID-19 drugs?
Use existing drugs
Therefore, for the treatment of patients with COVID-19, drugs that are already known and approved for use in the fight against other diseases will be redesigned.
The first step to using existingdrugs for the treatment of coronovirus has become a study of its composition. At the end of March, scientists expressed viral proteins: the study showed that SARS-CoV-2 contains about 66 proteins, each of which has several ligand binding sites - specific sites on the DNA molecule to which protein or other ligand molecules bind.
Further study revealed the most importanttarget proteins, the effect of which will lead to the destruction of the virus and the patient's recovery. Among them are papain-like protease, RNA-dependent RNA polymerase, helicase, protein S and ADP-ribose diphosphatase.
Then scientists found out (studies here, hereand here) that drugs designed to treat acute respiratory syndrome (SARS), Middle Eastern respiratory syndrome (MERS), HIV / AIDS and malaria act on the same targets. This means that drugs for these diseases can potentially cope or at least improve the condition of patients with COVID-19.
Chloroquine and its associated hydroxychloroquine -some of the most popular drugs tested for efficacy against the SARS-CoV-2 virus. The drug, which was previously used to treat malaria, on March 28 received from the FDA - one of the most reputable agencies for assessing the safety and effectiveness of certain drugs - approval for use in an emergency.
It is worth noting that in an epidemic of FDA notconducted a full test of the drug (this is evidenced by the EUA license), and allowed to use it only as an experimental treatment for emergency care in patients who are hospitalized but cannot receive treatment as part of clinical trials of new drugs. At the same time, the effectiveness of the drug remains in question.
Brazil's hospitals ceased on April 12Clinical trials of chloroquine for the treatment of COVID-19. This happened after several patients who were given the drug developed irregular heartbeats, which led to 11 deaths. This is only one of the side effects of the drug: among others, for example, toxic psychosis.
In this regard, doctors refused to use the drug for the treatment of severe patients with concomitant cardiovascular diseases. Such patients are most at risk with COVID-19.
However, now the drug is passingclinical trials as a means for the prevention of the disease - primarily among medical professionals. Such studies are carried out by scientists from Duke University, Oxford University and New York University Langon. According to the recommendations of the Ministry of Health of Russia, hydroxychloroquine, as well as several other drugs, can be used for patients with diagnosed coronavirus.
In March, the National Drug AdministrationChina approved the use of Favilavir for the treatment of coronavirus. This is a Japanese antiviral drug for treating influenza. This statement was made according to the results of clinical studies involving 320 patients, which were conducted in Shenzhen and Wuhan.
In 35 patients, the test for the presence of coronavirus was negative after four days, and patients who did not receive the drug were sick for an average of 11 days.
In a study in Wuhan at 240in patients with pneumonia, half received favipiravir and half received Umifenovir. Scientists found that patients recovered faster from coughing and fever with treatment with favipiravir, but there was no change in how many patients in each group went to the later stages of the disease.
At the end of March for clinical trialsFavipiravira in hospitals in three regions has begun Italy. Germany also announced plans to purchase the drug from Japan. At the same time, doctors warn that it is unsafe to use during pregnancy, and in severe cases of the disease, when the viral load is already high, it is almost ineffective.
Viferon and Arbidol
"Arbidol" - the trade name for the antiviralUmifenovir drug developed in the USSR. At the beginning of the epidemic, the drug manufacturer actively positioned it as a means of combating a new type of coronavirus. However, its effectiveness and safety have not been proven in studies conducted according to international quality standards. Despite this, in Russia, umifenovir is included in the government list of vital and most important drugs.
Another drug, Viferon, whose effectiveness has also not been proven, has been proposed by some Russian hospitals as a means of preventing coronavirus infection.
For example, one institution’s recommendations haveinstructions to take Viferon. Perhaps this prescription appeared due to a reprint of a study from China, which speaks of the discovery of a protective effect in intranasal recombinant human interferon for health workers from infection with coronavirus. No scientific studies of the effectiveness of the drug against COVID-19 have been reported.
Mefloquine is another drug for the prevention andtreat malaria. On April 23, the Federal Biomedical Agency of Russia (FMBA) of Russia revealed the first results of clinical trials of the drug - 78% of the patients participating in the testing showed positive dynamics.
Two drugs are participating in the study - mefloquine and the hydroxychloroquine mentioned above, the effect of which is tested in 347 patients with confirmed coronavirus.
According to preliminary results, 78% of patientswith a moderate to severe condition, positive clinical dynamics are noted. All patients showed satisfactory tolerance of mefloquine. However, an unambiguous conclusion can be made no earlier than May 20.