There is insufficient evidence to objectively verify whether the Sputnik vaccine developed in Russia is harmful to humans.
The vaccine has been given to 76 volunteers as part of two early-stage trials, but no results from those trials or other preclinical studies have been published. Even, Moscow-based Association of Clinical Trials Organizations (Acto) urged the health ministry to postpone approval until after phase-three trials. Meanwhile, the Russian vaccine is not among the World Health Organisation's list of six vaccines that have reached phase three clinical trials.
A novel vaccine candidate needs to be evaluated for safety, immunogenicity, and protective efficacy in humans before it is licensed for use. The Sputnik vaccine has not followed the usual clinical development path of a novel vaccine candidate, as per the guidelines issued by EMA, FDA, and USFDA. Researchers have said that the vaccine could be dangerous because it hasn't been tested in large trials. The Russians have skipped such measures, which could prove fatal to humans.
The effects of the vaccine could be felt on the long term and at this current time, the effectiveness or the problems caused upon administering the Sputnik vaccine cannot be determined.
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