Health Canada has confirmed that a residual DNA fragment containing an SV40 promoter-enhancer sequence was found in Pfizer-BioNTech’s COVID-19 vaccine, Comirnaty. 

But in its response to Conservative MP Glen Motz, the department gave few direct answers to his requests for records, dates, test results and correspondence with other regulators.

Motz’s 11-part parliamentary question asked when Health Canada first learned of the residual DNA, what Pfizer disclosed and when, and whether the department conducted or commissioned independent assessments. He also sought details about DNA associated with the vaccine’s lipid nanoparticles and communications with regulators in the United States, Europe, Britain and Australia. 

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In the response tabled September 21, Health Canada described the SV40 promoter-enhancer fragment as inactive, said it has no functional role in the vaccine and maintained that residual DNA levels are consistently below its required limit. It pointed to more than three billion Comirnaty doses administered worldwide, including more than 69 million in Canada, and said it had detected no related safety signal. 

The response did not provide the itemized records, dates, or other correspondences. Health Canada had also acknowledged the residual sequence in earlier parliamentary answers.