Stages of vaccine development
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The race to find a vaccine for the coronavirus outbreak is underway but vaccines go through multiple stages of development – from discovery to animal trials, human trials, regulatory approval and manufacturing
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Sars-CoV-2 virus

Fusion protein spikes

Human cell

Virus genome

ACE2 receptor

Protein spike is potential target for vaccine

*Angiotensin-converting enzyme 2

Fusion protein: Virus relies on protein “spike” to bind to ACE2* receptor – entry point into human cell for virus to replicate
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Pre-clinical development: Vaccine produces antigens to stimulate human immune system to generate antibodies

Antigen
Antibodies
Animal tests enable toxicology studies

Candidate vaccine: Tested in transgenic mice that have been modified with human ACE2 gene
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Phase I clinical trials: Evaluate vaccine’s safety and ability to generate immune system response in small group of volunteers
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Phase II testing: Several hundred volunteers – including some belonging to groups at risk. Trials are generally randomized to assess efficacy of vaccine
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Phase III: Large- scale trials to evaluate efficacy under natural disease conditions. If successful, maker applies to regulatory authorities for licence to market vaccine
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Phase IV: Large-scale manufacture. Quality-control and post-marketing surveillance to detect rare adverse effects
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© GRAPHIC NEWS
Sources: European Vaccine Initiative, MNT