Classen’s study establishes the potential for the messenger RNA (mRNA) vaccines developed by Pfizer and Moderna to activate human proteins to take on “pathologic configurations” — configurations associated with chronic degenerative neurological diseases. Although his specific interest is in prion diseases (conditions associated with misfolded versions of normal proteins), Classen also outlines a handful of other mechanisms whereby RNA-based vaccines could give rise to “multiple other potential fatal adverse events.”
Ensuring that patients clearly understand risks — including known risks as well as potential unknown risks— is an important component of the informed consent process. This is all the more true when the intervention is experimental and lacks long-term safety data, as is the case with the Pfizer and Moderna vaccines against COVID-19. The FDA authorized the two vaccines for widespread emergency use based on just two months of clinical trial data.