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When will a SARS-CoV-2 vaccine candidate demonstrate an efficacy rate >95% in a n>500 RCT?


The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus is a novel betacoronavirus that likely emerged late last year from an animal reservoir in China. There is little to no pre-existing immunity against it in the human population. The clinical picture for the disease it causes, coronavirus disease 2019 (COVID-19), ranges from very mild to fatal. The virus is highly transmissible and has spread globally.

As of 20 March 2020, the World Health Organization (WHO) is reporting that it is tracking the development of forty-four SARS-CoV-2 candidate vaccines. Two of these candidates have entered phase one and the other forty-two remain in the pre-clinical stage. There is an urgent need to determine when the first of one of these candidates will be found to have a high degree of efficacy.

The WHO defines vaccine efficacy as follows:

Vaccine efficacy: % reduction in disease incidence in a vaccinated group compared to an unvaccinated group under optimal conditions

This questions asks: When will a safe SARS-CoV-2 vaccine show efficacy rate >95% in n>500 randomized controlled trial?

This question resolves as the date when the first article is published that presents the claim that in a randomized controlled trial with at least 500 participants, the vaccine efficacy rate exceeds >95% when evaluated after at least one month after administering.

Further details:

  • This article must be authored by at least one of those involved in the funding, organizing, or researching of the relevant clinical trial.
  • The credibility of this article will be determined by Metaculus.
  • The article may be a pre-print and so need not be peer-reviewed.

If this does not resolve before 08 April 2023, it resolves as >08 April 2023.

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