Pfizer vaccine and lots with lower amounts of “intact” mRna – Corriere.it

A slowdown in vaccine supply and a quality problem in some batches produced in November. Pfizer has been in the limelight for days for two issues that, as the company itself explains, have nothing to do with each other. The first problem (a 29% drop in supplies in several European countries) is due, according to Pfizer, to the adaptation of facilities and processes at the factory, which requires new quality tests and approvals by the authorities. The stop also has the objective of expand production from February 15. The history of the inferior quality of some batches (already named Ema Leaks) refers to an exchange of confidential emails that took place in November between Ema (European Medicines Agency) and Pfizer. Ema would have discovered that some batches of Pfizer vaccines, intended for the population, were of lower quality than those used in clinical trials and would have asked the company to urgently solve the problem. The documents were then hacked and published on the “dark web” (it is not known if they were tampered with) and finally recovered by a group of Belgian journalists (from the “Behind the Pledge” project). We will discuss the matter a Report, on the Monday January 25 episode of Rai3.

The company resolved the reported issues

In an internal email on November 24, an EMA official reportedly spoke of differences in the level of integrity of mRna (Rna messenger), comparing the material for clinical trials and that of some batches destined for commercialization. The authors of Report let it be known that the EMA, requested by us, confirms that “during the evaluation questions were raised about the integrity of the mRNA for the Comirnaty vaccine (produced by Pfizer / BioNTech ed) “, Specifying that”the company was able to address these issues and provide the information and data necessary to issue the positive recommendation for the authorization of this vaccine”.

Adjustments may be necessary

Marco Cavaleri, responsible for the Ema vaccine strategy, consulted by Enrica Battifoglia of the agency Ansa, confirmed that in the production phase, and more markedly in the first test batches, the amount of intact messenger RNA in the vaccine base was less than that contained in the batches used in the clinical trial. We started the procedure in October continuous review of the Pfizer / BioNTech vaccine and in November we discussed the preliminary data submitted by the company for the start of commercial production, Cavaleri said. Pfizer / BioNTech is one of the first vaccines developed with messenger RNA technology. When it comes to biologics or next-generation products, such as the mRNA molecule encapsulated in lipid nanoparticles, adjustments may need to be made when the switch to bulk production occurs, Cavaleri noted.

a minimum threshold of mRna has been defined

We asked the company questions to understand what to do to keep levels as similar as possible to those observed with the doses used in the clinical trial and to understand the possible impact on the efficacy and safety of the vaccine. Questions to which, said Cavaleri, the company responded by giving explanations on both aspects. Further tests were conducted showing that Even a smaller amount of mRna could guarantee efficacy. and that the immune response to the vaccine does not change. Furthermore, degraded mRNA fragments, which are also present in clinical batches, are not a safety concern and are rapidly destroyed in the body. So, Cavaleri concludes, We have defined a minimum acceptable mRna threshold, which is capable of preserving safety and efficacy.: After examining more data, everything convinced us that the vaccine was suitable and the subsequent production was carried out in order to obtain batches with levels of mRNA as close as possible to those used in clinical studies.