Early Pfizer COVID-19 vaccine doses may have had potency problems

[Image courtesy of Wikimedia Commons]

Some of the first commercially available doses of Pfizer-BioNTech COVID-19 vaccine had lower levels of intact mRNA than anticipated, according to leaked documents reviewed by BMJ.

The documents in question relate to a December breach of the European Medicines Agency (EMA), which was one of the many victims of pharma-related cyber breaches in 2020.

The cybercriminals behind the attacks sent 40 MB of data to several journalists while also publishing them on the dark web.

The EMA has launched a criminal investigation related to the breach. The agency claimed in January that the leaked documents were modified. “A closer investigation of the published material has revealed that not all of the documents were published in their integral, original form and may have been taken out of context,” reads part of a statement.

Keanna Ghazvini, a Pfizer spokesperson acknowledged that some documents related to to the EMA’s rolling review of the Pfizer/BNT vaccine clinical program have been found online. “Discussions with the regulatory authorities about the vaccine’s quality aspects, including specifications, represent a normal component of the regulatory review process,” the spokesperson said. “All the topics that emerged during the procedure have been discussed transparently with the Agency, in accordance to the normal practices, and all questions have been duly addressed during the review process,” she added.

BMJ editors have reviewed the documents, which indicate that EMA officials were concerned about the low amounts of intact mRNA in early commercial batches of vaccines. According to one email, the impact of the loss is mRNA integrity has “yet to be defined,” according to one email.

An email from November 23 detailed concerns from a senior EMA official who worried that the early vaccine doses did not meet specifications, according to BMJ. The percent of intact mRNA in early doses was reportedly 55% to 78%.

EMA reportedly filed two “major objections” with Pfizer upon discovering the issues.

However, a later EMA email reported that the amount of intact RNA had risen to be in the range of 70 to 75%.

The organization authorized the vaccine on December 21. In February, it deemed the quality of the product to be “sufficiently consistent and acceptable.”

“The positive opinion granted by EMA and the subsequent conditional Marketing Authorization, issued on December 21, 2020, by the EC, are results of this process, meaning that all the questions raised during the procedure were addressed satisfactorily and the efficacy, safety and quality of the vaccine could be demonstrated on the data submitted,” the Pfizer spokesperson added.

The topic of mRNA stability does not apply only to Pfizer and its partner BioNTech. Several other companies, such as Moderna and CureVac, are also using the mRNA vaccine platform.