Adriana santagati
08/06/2021 12:04
Clarín.com
Society
Updated 08/06/2021 12:04
On a Qatar Airways flight, this Friday morning, the first batch of the Convidecia single-dose vaccine, developed by the Chinese laboratory
CanSino Biologics,
arrived in Ezeiza
.
There are 200,000 vaccines, out of a total contract of 5.4 million.
What is not yet clear, in this new heterologous vaccination scenario, is whether they will be used as a
second dose of Sputnik or as a single dose
for those who have not yet received any vaccine.
Convidecia - or CanSino, as it is popularly known - is the
only single-dose vaccine approved in the country
, since Janssen's has not yet obtained the endorsement of the National Administration of Medicines and Medical Technology (ANMAT) despite the fact that the process registration was presented in December of last year.
The CanSino clinical trial was also developed in Argentina with the participation of 8,000 volunteers, and part of them are currently studying whether a second dose can improve the immune response.
Similar
But beyond the advantage of requiring only one application for now, CanSino has another no less negligible in this context: its formula is based on
adenovirus 5
, precisely the same on which the second component of Sputnik V is developed, which both it is scarce today.
"The first dose of Sputnik can be combined with the CanSino vaccine. CanSino's has the adenovirus 5 vector, the same one that Sputnik V has in the second component," explains Eduardo López, government adviser infectologist and one of the researchers from the local CanSino essay.
"It's the most similar," he synthesizes.
So, the Chinese vaccine appears as the "ideal" option to replace the second dose of the Russian one.
But until now - because it was not available in the country - interchangeability was analyzed only with Moderna, AstraZeneca and Sinopharm.
The results were positive with the first two, which since this Friday have already begun to be applied to those who have been waiting longer for Sputnik V or are in a higher risk situation.
Second or first?
August will be the month of the second doses, said Minister Carla Vizzotti, and Alberto Fernández remarked with the announcements this Friday that this month "we are going to apply more than 7 million second doses."
But it has not yet been officially announced if that will be the fate of the CanSino.
From the City, they told
Clarín
that they are waiting for the officialization of the Nation, but they anticipated that they will apply them to those who did not receive any vaccine and did not rule out adding them to the combination study that already gave preliminary results on which this was endorsed. new strategy.
The Province, meanwhile, confirmed that
CanSino is going to join the interchangeability test
.
In Buenos Aires territory they believe that the use of Chinese vaccines would be ideal to combine or to apply in minors, two indications not yet approved other than to use as the first (and only in this case) dose, because most of those over 18 already they received it.
López agrees with this same analysis.
According to official data, in the province 80% of the 18+ already have at least one dose and in CABA, 85%.
For the infectologist, with this high percentage of the population with a vaccine, he should bet on completing the schedules with two doses to face the Delta variant.
And he does the math: 200,000 doses of CanSino represent roughly
5% of the people waiting for Sputnik Component 2
.
Now, without Sputnik 2, of all the available options, what is the best combination for Sputnik 1?
First, Sputnik 2
, López insists.
But in the absence of the second component, "if Sputnik V behaves like AstraZeneca, the first option would be
a messenger RNA vaccine like Moderna or Pfizer
, homologate what was studied in England", since a more complete stimulation of the immune response with the combination of these platforms.
Second, the infectologist proposes the vector vaccine + vector combination, and
in this case he puts CanSino
, clarifying that it must be tested in a trial.
The results would be quick, because already at 14 days a cut can be made and see what happens with the antibody titers.
"With AstraZeneca, on day 14 he lifted them three times," he explains about the local interchangeability study.
CanSino and the Delta
The CanSino vaccine received its emergency approval in the country in June of this year, the same month in which the Argentine government signed a contract for
a total of 5.4 million doses
with the Chinese laboratory.
The effectiveness of the unit dose is 65% for all forms of Covid compared to traditional variants (without the Delta or South Africa) and 91% for severe forms, explains the infectologist at the Gutiérrez hospital.
What happens in front of the Delta?
"As far as I know there are no data regarding the Delta, perhaps they have them in China and they have not yet been published," says López, but clarifies that
all vaccines lose their effectiveness against this contagious variant
.
For this reason, he remarks, they are studying whether a second dose of CanSino is necessary, the same as they are evaluating with Janssen, the other single-dose vaccine available for now.
ACE
Look also
Sputnik 1 + Sputnik 1: the other test to combine vaccines that is already done in the City
"I do not get together with anyone and I wait from April 9", the experience of the first to receive combined vaccines
