Health Canada’s Request to Pfizer for DNA Fragment Sizes in COVID Shots Possibly Linked to Genomic Integration Probability
Canada’s drug regulator asked Pfizer to provide data on the size of DNA fragments in its COVID-19 vaccine, due to genomic integration concerns, shortly after learning the pharma giant withheld information on DNA sequences contained in its product.
“Concerning the residual plasmid DNA in the drug substance, provide data/information characterizing […]
the size distribution of the residual DNA fragments [and] residual intact circular plasmid,” says a request for clarification Health Canada issued to Pfizer on Aug. 4, 2023.
The information was released as part of records obtained through an access-to-information request. It shows, in part, that a Health Canada official was keeping the department’s counterparts in the United States and Europe apprised of the department’s interactions with Pfizer, in a bid to harmonize the regulators’ approaches regarding the recently discovered DNA fragment impurities.
“As you are aware, the fragment size is related to the probability of integration, and the WHO guidance assumes a fragment size of generally less than 200 bp,” Dr. Dean Smith, a senior scientific evaluator in Health Canada’s Vaccine Quality Division, wrote in an October 2023 email to counterparts at the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA).
guideline
established by the World Health Organization (WHO) and followed by Health Canada, according to the official records.
This assertion has been challenged by independent scientists, who found quantities of DNA in the vaccines to be above the threshold. They have also found the DNA fragments are larger than 200 base pairs (bp).
studied
Canadian mRNA vials, told The Epoch Times the average size of fragments his study found is 214 base pairs (bp), with some as large as 3.5 kilobase (kb).
While small fragments frequently integrate spontaneously into the genome, these mutations are stopped through either DNA repair mechanisms or cellular death, Dr. Speicher said.
“Larger fragments are much more problematic, especially if attached to an SV40 enhancer, because they can integrate into the genome where they can get transcribed and then translated into proteins,” he added. Independent scientists like Dr. Speicher found the undisclosed SV40 enhancer in Pfizer shots, a piece of biotechnology used to drive gene expression.
Depending on the DNA fragment size, it can produce functional or aberrant proteins, Dr. Speicher explains. “These proteins can affect cellular metabolism, an immune response, as well as an increased risk for cancer. The risk of integration and associated health problems increases with the number of shots.”
called
for a halt of mRNA shots, citing concern about these risks. Dr. Philip Buckhaults, professor of cancer genomics and director of the Cancer Genetics Lab at the University of South Carolina, has initiated a
study
to investigate the risks.
told
The Epoch Times last summer “the presence of residual plasmid DNA in the mRNA COVID-19 vaccines does not change the safety assessment of these vaccines.”
Seeking Clarifications
Despite providing this answer to media in the summer of 2023, Health Canada scientists were privately discussing working with international partners to have Pfizer remove DNA fragments and SV40 sequences from its vaccines and they prepared several requests for clarification to the company.
In an August 2023 email to a colleague providing information to relay to Pfizer, Health Canada senior biologist evaluator Dr. Michael Wall said his department would “continue to work with international regulatory partners to achieve harmonization regarding removal of these sequence elements from the plasmid for future strain changes.”