Understanding the Pharmacology of COVID-19 mRNA Vaccines: Playing Dice with the Spike?
Defining COVID-19 mRNA vaccines as pharmaceutical drugs has straightforward implications for their assessment and for their safe, rational and individualized use.
1. Introduction
In most Western countries, the mass Coronavirus disease-19 (COVID-19) vaccination campaigns, which have been ongoing since the end of 2020, are based on two mRNA vaccines against SARS-CoV-2 (BioNTech–Pfizer BNT162b2 and Moderna mRNA-1273)1,2. Both products contain mRNAs encoding the SARS-CoV-2 spike (S) protein, which is essential in the binding of the virus to the host cells expressing its receptor angiotensin-converting enzyme 2 (ACE2). These products were presented from the outset as intrinsically safe, since it was believed that, similar to conventional vaccines, after intramuscular injection, most of the dose would remain in the muscle and the rest would drain through the lymphatic system, being eventually captured by antigen-presenting cells and B cells and undergoing complete elimination in a few tens of hours at the most3,4. On this basis, the public was explicitly reassured by influential blogs (see for example 5) as well as by academic institutional web pages (see for example 6) that these products were not expected to exhibit any relevant systemic disposition and that the resulting S protein would remain attached to the surface of the cells and would not be released in the bloodstream and tissues to encounter ACE2 receptors and eventually induce organ damage. Step by step, however, it became clear that this was not the case.
The full version of the paper is available at: https://www.mdpi.com/1422-0067/23/18/10881/htm
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Thank you for this detailed, sharp critique. I find it astonishing that the world is now in the situation it is. We must fight for integrity and freedom of speech. Maurice McCarthy, Swansea, United Kingdom.