Mix vaccines, Remuzzi: “More effective, we have the evidence”

“The research done so far confirms that the mix of” anti covid vaccines for the second dose “not only works but guarantees better coverage”. Giuseppe Remuzzi, director of the Mario Negri Irccs Institute of Pharmacological Research, writes it in ‘Il Corriere della Sera’. “Could it be that in proposing the recall with Pfizer or Moderna in those who had already done AstraZeneca, CTS and the government they let themselves be conditioned by the death of the girl from Sestri Levante?”, Remuzzi asks. “Doing the first dose with a certain vaccine and the second with another (they called it heterologous vaccination) is not something of today; two different vaccines were first tested in Paris 34 years ago for HIV and yes the idea was immediately clear “. “Now those who work on HIV follow the path of heterologous vaccination (opened by Daniel Zagury at Pierre and Marie Curie University in 1987) and the same is done for Ebola, tuberculosis, Epstein-Barr and other diseases – continues the director – has already been done for Sars-CoV-2: Sputnik is in fact a heterologous vaccination, given that the adenovirus of the first dose is different from that of the second (and the interim analysis of phase three data demonstrates an efficacy of 91.6% and a good tolerance) “.” Before reaching humans, researchers tried all possible combinations in animals, to conclude that the heterologous allows the immune system to recognize and neutralize the intruder – in our case the virus – in different regions and this increases the effectiveness of vaccination. For Sars-CoV-2 the combination of the two vaccines exploits the peculiarities of each of the two: AstraZeneca generates T (killer) lymphocytes that attack the cells infected by the virus to then destroyed gger them; mRna vaccines, on the other hand, mainly provoke an antibody response “, he warns.” How do we know? From the Spanish study: 663 people under 60, who had already received AstraZeneca, were receiving Pfizer-BioNTech after 8 weeks. Preliminary data, announced on May 18, show that heterologous vaccination is highly immunogenic and generates antibodies that recognize and inactivate Sars-CoV-2 (in laboratory tests) more than has ever been seen with any combination of homologous vaccine ” Remuzzi remembers. Then there is a study done in Germany by the department of virology of the University of Ulm. “It’s true they are not yet published but they will be soon and anyone can see them in ‘medRxiv’ in the form of a non-definitive publication. , accessible to the scientific community. These are – Remuzzi reconstructs – 26 people who received AstraZeneca, followed after 8 weeks by Pfizer, in which a powerful immune response and above all an increased reactivity of T cells against Sars-CoV-2 was recorded. But the most interesting part of this study is that, at least in laboratory tests, the serum of subjects treated with two different vaccines inactivates the English, South African and even the Indian variants (it is called delta and is the one we are all so afraid of) “.” Of course, 26 patients are not many, but the study is so elegant that it leaves little doubt. Also on medRxiv there are the data of another study done in Berlin this time: the patients are more (340) and they are doctors or nurses. It turns out that doing AstraZeneca first and then Pfizer with 10-12 weeks of interval gives a strong immune response and is very well tolerated. And that’s not enough, in a few weeks they will finish the studies begun in England for many months now. This time the ‘patients’ (in the sense that they have had the patience to undergo different vaccination schemes) are many more: 830. One group received Astr Zeneca and then Pfizer 4 or 12 weeks later. And then the opposite, first Pfizer and then AstraZeneca, always with different intervals of administration. And there are the ‘controls’, that is, the booster was made, with the same preparation at the same intervals, in order to demonstrate that the heterologous vaccination really offered measurable advantages “.” To be honest, the heterologous vaccination has a few more disorders than that with two doses of the same vaccine he gives it. Fever, especially – in the days following the second dose – in 34% of cases – Remuzzi warns – And then there can be fatigue, joint and muscle pain. It happens in 20-30% of cases, both with heterologous and traditional vaccination, but everything is resolved in a few days, and none of those who took part in the English study had to be hospitalized. Thus heterologous vaccination is one of the possible solutions to vaccinate Europe and perhaps the world soon, and if what we have seen in the laboratory also happens in vivo, who knows if it is not the way to counteract the variants, for which a solution soon “.