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Will covid-19 vaccines save lives? Current trials aren’t designed to tell us

BMJ 2020; 371 doi: (Published 21 October 2020) Cite this as: BMJ 2020;371:m4037

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Covid-19 vaccine trial protocols released

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Re: Will covid-19 vaccines save lives? Current trials aren’t designed to tell us

Dear Editor

A newly published article by Timothy Cardozo and Ronald Veazey “Informed consent disclosure to vaccine trial subjects of risk of COVID‐19 vaccines worsening clinical disease” reports on a study to determine whether or not sufficient literature exists “to require clinicians to disclose the specific risk that COVID-19 vaccines could worsen disease upon exposure to challenge or circulating virus.” (1)

The authors concluded that it did.

The results of the study………….

“……..that vaccines designed empirically using the traditional approach (consisting of the unmodified or minimally modified coronavirus viral spike to elicit neutralizing antibodies), be they composed of protein, viral vector, DNA or RNA and irrespective of delivery method, may worsen COVID-19 disease via antibody-dependent enhancement (ADE). This risk is sufficiently obscured in clinical trial protocols and consent forms for ongoing COVID-19 vaccine trials that adequate patient comprehension of this risk is unlikely to occur, obviating truly informed consent by subjects in these trials.”
The authors concluded that………….

“The specific and significant COVID‐19 risk of ADE should have been and should be prominently and independently disclosed to research subjects currently in vaccine trials, as well as those being recruited for the trials and future patients after vaccine approval, in order to meet the medical ethics standard of patient comprehension for informed consent.”

Along with an inability to prove a reduction in the likelihood of severe illness and hospitalisation and prevent infection in interrupting transmission etc the current trials may also be falling foul of what constitutes informed consent from trial participants in failing to disclose a “specific and significant” Covid-19 risk of ADE.

Looking to the future, the authors concluded that the risk should also be disclosed to “future patients after vaccine approval”.

The fact that Covid-19 vaccines could worsen disease when exposed to challenge or circulating virus, is something that every individual should be aware of before consenting to vaccination.

It will be interesting to see if this comes to pass.

( 1)

Competing interests: No competing interests

30 October 2020
Wendy E Stephen
Retired nurse
Stonehaven, Scotland