The epidemic will be over after more COVID-19 oral drugs are approved?

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The epidemic will be over after more COVID-19 oral drugs are approved?

The epidemic will be over after more COVID-19 oral drugs are approved? Many COVID-19 oral drugs have been approved. How will they change the trend of the epidemic?

At the end of 2020, a number of COVID-19 vaccines were launched in the early winter wind in the northern hemisphere. The light at the end of the anti-epidemic tunnel seemed to be within reach.

However, the virus mutation and vaccine efficacy problems followed one after another, and the world was still caught in the COVID-19 epidemic in 2021.

Another winter is coming, and the breakthrough progress of COVID-19 oral drugs once again brings new hope.

The world’s first anti-coronavirus oral drug, molnupiravir, jointly developed by Merck and Ridgeback Biopharmaceuticals, was approved in the UK on November 4 this year.

The interim analysis data of the phase III clinical trial showed that the drug can reduce the risk of hospitalization and death of patients with mild to moderate COVID-19 disease by about 50%.

The European Medicines Agency recommended on the 19th that Monabiravir can be used to treat adults who do not need oxygen support and are at risk of severe illness.

Immediately afterwards, the US pharmaceutical company Pfizer announced on November 5 that its oral COVID-19 drug candidate Paxlovid can reduce the risk of hospitalization and death by 89%.

The company has submitted an application to the U.S. Food and Drug Administration on the 16th to apply for an emergency use authorization for Paxlovid.

In addition, a research report published in The Lancet at the end of October showed that fluvoxamine, a commonly used antidepressant, can also reduce the risk of severe illness and death from the COVID-19, but it has not been proven to be widely used in the treatment of COVID-19.

Although oral medicine is generally regarded as an important breakthrough in the fight against the epidemic, it is not a substitute for vaccines.

An epidemiologist at the University of Michigan told Bloomberg: “It may ultimately be the combination of drugs, vaccines and natural immunity that can inhibit the serious complications of the COVID-19, thereby allowing people to live normally without taking preventive measures.”

What are the advantages of oral medicine?

In the technological battle against the COVID-19 virus, drugs such as Remdesivir and Dexamethasone have been used to treat patients with COVID-19s, which has greatly reduced the mortality rate.

After that, the injection of monoclonal antibodies showed an immediate effect, but the premise is that the infected person can be admitted to the hospital for treatment and can afford the high drug prices-the monoclonal antibody drug produced by the US drug maker GlaxoSmithKline is priced at 2,100 per dose. US dollars.

In contrast, the barriers to obtaining oral COVID-19 drugs are lower. According to the “New Yorker” report, Monabiravir is an orange capsule.

Patients with COVID-19 infections start taking the drug within 5 days of the onset of symptoms, taking 4 capsules twice a day, and a course of treatment can be completed in 5 days. .

In the United Kingdom, patients with mild to moderate COVID-19 and those at risk of severe disease are allowed to use Monabiravir.

It has some similarities with the flu drug Tamiflu, including functions and ease of use. But the pharmacological mechanism is different.

A scholar from Edinburgh Napier University explained to the British Broadcasting Corporation (BBC) that the pharmacological mechanism of Monabiravir is to interfere with the genetic code of the virus, so that the virus is excessively mutated so that it cannot replicate completely, and then disappears on its own.

Paxlovid developed by Pfizer belongs to the class of protease inhibitors. It contains the anti-coronavirus drug PF-07321332 and low-dose ritonavir, which works by blocking the main protease required for virus reproduction. A course of treatment of this medicine is also 5 days, taking 3 capsules 2 times a day.

Both small molecule drugs can be taken orally instead of intravenously. Joan Lane, head of the British Medicines and Health Products Administration (MHRA), pointed out that this convenience is very important, so that people infected with the COVID-19 can receive timely treatment outside of hospitals and medical institutions, and reduce the risk of developing severe illness. At the same time reduce the pressure on the medical system.

Right now, the US government has reached an agreement with Pfizer to pre-order 10 million courses of Paxlovid and pay US$5.29 billion for it.

This means that the price of a course of medicine is about 529 US dollars , but the authorization is pending approval. The price of Monabiravir is slightly higher, and the cost of each course of treatment is approximately US$709.

Questions about effectiveness and safety?

Oral medicine has become the latest equipment in the anti-epidemic ammunition library, but it faces many doubts while being high expectations.

Both Merck and Pfizer provided interim analysis data for Phase III clinical trials, which is a node where a drug trial is subject to safety testing to determine whether to continue.

Simply put, the relevant experimental data of the two drugs are incomplete and have not been published in peer-reviewed professional journals.

According to trial data provided by Merck, patients with COVID-19 infection who take Monabiravir within five days of the onset of symptoms can reduce the risk of hospitalization or death by 50%.

However, Merck did not provide data on taking the drug within three days of onset. Pfizer’s test data also only comes from the test results of patients within three days of infection.

Edward Mills, a researcher at McMaster University in Canada, said that the test data provided by the above-mentioned drug maker was plausible. “The reality is that most people just feel unwell a few days before being infected with the COVID-19, and then they go to a doctor and get tested. The whole process often takes more than 3 days.

According to the “New York Times” report, from the current trial, it is known that the COVID-19 oral drug treatment must be carried out within the first few days of the patient’s symptoms.

Experts predict that this will be very difficult in countries where it is difficult to obtain reliable medical services. If the time of taking the medicine is delayed, the effect will be compromised.

However, some medical experts believe that they can take the opportunity to promote the transformation of epidemic prevention.

Once people have respiratory symptoms, they will immediately self-test to speed up the return to normal life.

As for the safety of the drug, both Pfizer and Merck stated that there were no reports of deaths in patients taking the new drug, and the side effects were mostly mild, which were comparable to those observed in patients receiving a placebo.

Because Monabiravir works by destroying the way the new coronavirus replicates RNA, there is concern that the drug may have a similar effect on human DNA or RNA.

“The New Yorker” reported on the 21st that a recent study showed that high-dose and long-term use of Monabiravir may cause gene mutations in normal cells of the body.

In this regard, British biochemist Derek Lowe pointed out in an article published in the journal Science that the above findings may not be applicable to the actual situation of COVID-19 patients’ medication, because that test was performed in cells.

Is carried out in the process, not live animals or humans. In fact, if the cells are exposed to the drug for more than a month, even at the highest dose, there will be fewer mutations than short-term exposure to ultraviolet light.

What changes have been made to the distribution rules?

According to data released by the WHO, as of October 28, only about 77 million people in Africa, or 6% of the population, have completed the COVID-19 vaccination, while more than 70% of the world’s wealthy countries have achieved a population of more than 40%. Complete the goal of COVID-19 vaccination.

While some of the countries with the highest vaccination rates continue to stock more vaccines, low-income countries are still waiting for vaccines.

Will the arrival of the COVID-19 oral medicine repeat the mistakes of the vaccine divide?

Pfizer issued a statement on November 16, stating that it has signed an agreement with the Medicines Patent Pool (MPP) supported by the United Nations to grant sub-licenses to qualified generic drug manufacturers, allowing generic drug manufacturers to grant 95 medium and low The receiving country supplies its oral anti-coronavirus drugs.

The 95 countries in the agreement cover approximately 53% of the world’s population.

Merck previously signed a similar agreement to allow 105 poorer countries to produce and sell Monabiravir cheaply.

The United Nations news website reported that permitting the production of COVID-19 generic drugs is an important first step to help ensure that the latest anti-epidemic tools are available on a global scale.

Charles Gore, executive director of MPP, told US media that vaccines are still difficult to obtain in most parts of the world, and oral drugs for the COVID-19 are relatively cheap and easy to use. “They are changing the rules of the game.”

When the drugs of the two companies can be used as generic drugs, it is possible for doctors to combine the two drugs as a treatment.

Unfortunately, some countries that have been hit hard by the epidemic have been excluded from the agreement between the two companies.

The New York Times stated on the 16th that although Merck and Pfizer’s agreement covers more than 100 countries, Brazil, Cuba, Iraq, Libya, Jamaica and other countries have been excluded, and these countries are still suffering from the epidemic and they must not Do not purchase COVID-19 oral drugs at high prices, and the supply is worrying.

In fact, the two oral medicines had already been produced before they were approved by the regulatory agency. Pfizer plans to provide 50 million courses of drugs in 2022.

Merck plans to complete the production of 10 million courses of drugs by the end of this year. According to the report, scientists are thinking about what will happen to the new coronavirus when these drugs are used on a large scale, and whether people have another excuse to avoid vaccination.