Russia clears sputnik light vaccine in lack of second dose

The announcement of the approval in Russia of the use of half Sputnik V vaccine to fight against the coronavirus, under the label of “Sputnik Light”, arrived late Wednesday evening, although it was only allowed to be broadcast in Argentina on Thursday. The reduced version of the vaccine developed by the Gamaleya Institute with a single component and a single dose, is identical to the first half of the “traditional” vaccine. The Russian Direct Investment Fund (RDIF) guarantees 79.4% protection after 28 days of administration.

The subject will undoubtedly generate an important controversy in Argentina, given the large population of older adults who received the first component of the Sputnik V vaccine, with the government’s promise to receive the second dose three months later, which now appears to be in failure. However, this Thursday, the Minister of Health, Carla Vizzotti, assured at a press conference that they were working for the second doses to arrive.

But it doesn’t seem unreasonable to think that now could change the vaccination strategy with this vaccine, since, while the traditional version of Sputnik is composed of two doses with two different components of adenovirus (Ad26, first, and Ad5, in the second dose), the limited version contains only the first component, at namely, recombinant human adenovirus serotype 26.

According to the developers (the Ministry of Health of the Russian Federation, the Gamaleya National Research Center for Epidemiology and Microbiology and the Russian Direct Investment Fund, or RDIF), an analysis was conducted on the Russian population who had only agreed to receive the first dose of the full vaccine.

“Phase I / II studies on the safety and immunogenicity of single dose vaccine they started in January 2021, and the provisional results were obtained on March 10, ”they specified.

In this period it was observed an efficiency of 79.4%, based on data analysis on day 28, post-vaccination. As they pointed out, the vaccine “is effective against all new strains of coronavirus, according to the results of laboratory studies of the NITsEM NF Gamaleya Center ”.

They also ensure that immunization with the “light” version allows the development of antigen-specific IgG antibodies in 96.9% of vaccinated people, four weeks after administration. And that, also from that moment, Neutralizing antibodies are produced in 91.67% of people who received this unit dose.

The morbidity rate of vaccinated citizens, on the 28th day from the date of vaccination, “was only 0.277%. At the same time, the incidence among the unvaccinated adult population, measured over a comparable period, was 1.349% ”, explains the press release, without however clarifying anything in relation to the persistence times of antibodies in the body.

Regarding the effectiveness of the light version, they explained that it was calculated according to the following formula: the incidence of Covid among the unvaccinated population (1.349%) minus the incidence among the population vaccinated with one dose (0.277% ), all divided, then, by the incidence among the unvaccinated population (again, 1.349%). The result is 79.4%.

In addition, they assured, “the cellular immune response to the S protein of SARS-CoV-2 is already induced on the tenth day in 100% of vaccinated people”, a subject that could cause controversy among experts, at least. until the publication of specific information on these points in the usual channels managed by the scientific field.

Cost and security

“No serious adverse effects were recorded after vaccination with Sputnik light ”, they assured in the RDIF press release, and underlined the economic benefit representing this single-component, single-dose vaccine.

“As of May 5, 2021, more than 20 million people around the world had received the first dose of the Sputnik V vaccine. Sputnik light does not require special storage and logistics conditions and has an affordable price of less than $ 10. The administration schedule with a single dose allows in a short time immunize a large number of people and reduce epidemiological peaks“, They stressed.

AS