RESPONSE FROM EMA: “Vaccines may contain residual amounts of viral or cellular DNA fragments (depending on the manufacturing process) that originate from the processes used for their manufacture and this is not considered a contaminant but a residual substance. During the evaluation of the manufacturing process for any medicinal product, including vaccines, the possibility of impurities and endogenous viral contaminants is always investigated.
Although the manufacturing process of vaccines is strictly controlled and designed to minimise residual DNA to within acceptable limits, the presence of trace amounts of such residues is inevitable. This is not considered to pose a risk for recipients of the vaccines and there has been no identified link between its presence and any adverse events.
Regarding host related impurities for Gardasil, the clearance and estimated amount of DNA and RNA was evaluated at the time of the marketing authorisation application (MAA) and it was within the acceptable limits. The DNA assay validation was described in the dossier and assessed by the CHMP. The results confirmed the sensitivity of the residual DNA method for samples from the manufacturing process.
The findings of residual amounts of viral DNA fragments referred to in the question are an expected finding and data in the literature supports that the residuals are rapidly eliminated and do not result in any expression of protein. The findings do not support that Gardasil is contaminated with HPV DNA and have no impact on its benefit risk balance.
We would like to inform you that for vaccines, as for any other medicinal product, a thorough evaluation of its quality, safety and efficacy is undertaken prior to approval. In addition, the EMA takes very seriously its role in protecting public health by monitoring medicines already on the market, and as such, the quality, safety and efficacy of all medicines, including all vaccines, are continuously monitored.
See also responses to questions under the section ‘other concerns, preclinical questions I.a/b. ”