Vaccines that can reach Argentina advance, with tentative results

The North American companies Pfizer and Biontech have published the first results of the effectiveness of a vaccine. This is the data from Phase 3, the last one that must pass before receiving approval for use.

Meanwhile, Russian authorities have confirmed that in two weeks the first results of Sputnik V will be known, although a representative of the Russian Ministry of Health already predicted that it would also exceed that figure.

For now, the Argentinian government has only signed an agreement with AstraZeneca, a UK-based company, for 22 million doses that would arrive in the first half of 2021.

Yesterday’s announcement from Pfizer is exciting, but it should be taken with caution for several reasons. The first is that it was reported by the company itself in a press release and not in a scientific publication. In addition, this is an interim analysis that does not yet take into account data from the more than 40,000 volunteers participating in the trial.

The surprise is that the reported efficacy was 90%. The FDA, the US regulator, had said it would only allow vaccines that were at least 50% effective, and researchers expected that figure to not exceed 70%.

What is missing

Pfizer is expected to apply for authorization for its emergency use in the United States by the end of November, when safety concerns are analyzed in half of the trial volunteers and two months after vaccination.

This vaccine has certain disadvantages to administer. The first is that two doses should be given 21 days apart. Like all vaccines, immunity is achieved several days after the second dose. Another problem is that it must be stored at subzero temperatures before use. This poses logistical challenges in international sourcing and local distribution.

It is also not known whether it prevents the occurrence of severe cases and whether it prevents people from being infected asymptomatic who can also infect.

Another information which is not known is the duration of protection against the virus. In fact, these data are unknown for all vaccines. Regarding the side effects, it is known to cause pain and fever.

This is a messenger RNA (mRNA) vaccine that inoculates the genetic material of the virus so that the host itself makes the viral protein. The immune system recognizes this and creates antibodies, which are ready to defend itself in the event of a real infection. There are no vaccines with this platform on the market.

Russian waiting

Meanwhile, Russian vaccine Sputnik V is also set to release interim results for its phase 3. This will take place in November, as reported yesterday at a press conference by the Russian Direct Investment Fund (RDIF, for its acronym in English).

“Our position is one of total transparency. We are totally open as a country to give information, ”said Kirill Dmitriev, CEO of RDIF.

Meanwhile, Denis Logunov, deputy director of the Gamaleya Institute that developed the vaccine, said 20,000 volunteers received the first dose and 14,000 the second. “In a short time, we will communicate the results with 10,000 volunteers to the Argentine authorities,” Dmitriev added before a request. The final results of phase 3 would be in four months.

Anyway, Oksana Drapkina, director of a research institute under the Russian Ministry of Health, said: “According to our observations, its effectiveness is also over 90 percent.”

Regarding the possibility of 25 million doses reaching Argentina in December, Dmitriev said the timeline depends on Argentina’s approval. “There are many aspects to take into account in the delivery. Approval is very important. We hope it will be done quickly, as soon as possible, ”he said. And he added: “Most of the doses will be delivered in the first four months of 2021, but we hope to start with the delivery in December.”

The Russian vaccines our country will receive will in fact be supplied by India, South Korea and China, countries which have not yet started production.

Sputnik V uses other harmless viruses (adenoviruses) as a platform that work as a vector to transport the genetic material of Sars-Cov-2 to human cells. Stakeholders stressed that this platform is safe because it has already been tested in other vaccines and drugs.

Gamaleya has developed vaccines against Ebola and Mers (another coronavirus) with the same adenovirus platform. They were granted immunity for two and one years, respectively. “While we cannot say it will last the same, we are confident that a prolonged effect will occur, as we are seeing in animal research,” Logunov said.

This immunization has two formulations: a liquid, at “refrigerator” temperature, and another in powder to be diluted. It also requires two doses. “All vaccines have side effects and are the norm for everyone: pain at the application site, headache and fever,” he added.

From England

For its part, the company AstraZeneca announced on Saturday the signing of an agreement with the Argentine government to provide more than 22 million doses of its vaccine, developed by the British University of Oxford. Deliveries would start in the first half of 2021, in case the trials are successful

This vaccine uses the non-replicating viral vector platform with a chimpanzee adenovirus. It is being tested in England, India, Brazil, South Africa and the United States, in phase 3 trials. In August, it was announced that the Argentinian company mAbxience would be one of the manufacturers of the active substance. . The trials were halted in September due to the death of a volunteer due to transverse myelitis. This vaccine also requires a second dose 28 days after the first.

Other advanced vaccines

Argentina is also negotiating an agreement with vaccines developed by Sinopharm (China) and by Janssen-Johnson & Johnson, also in phase 3 and with clinical trials in Argentina. Other advanced vaccines are Moderna and Novavax, from the United States; Cansino and Sinovac, from China; Bharat (India) and Brace (Australia).