Efficacy and Safety Learnings From COVID-19 Vaccine Trials

Karine Lacombe, MD, PhD


June 01, 2023

From the outset of the COVID-19 pandemic and the rapid development and deployment of vaccines, extensive studies have been conducted to assess their safety and efficacy. Over the past 2 years, clinical trials have continued to yield valuable insights into the safety, immunogenicity, and efficacy of the original vaccines, boosters, and newer vaccine variants.

Dr Karine Lacombe, from the Department of Infectious Diseases at Hospital St. Antoine in Paris, France, provides a comprehensive review of key data obtained from global trials that demonstrate the effectiveness of currently available vaccines against the more recent SARS-CoV-2 variants. Dr Lacombe compares the efficacy of different vaccine platforms and addresses the occurrence of adverse events resulting from vaccination, emphasizing their rarity and manageability.

Additionally, Dr Lacombe reviews data on hybrid immunity — the immunity derived from a combination of infection and vaccination — and its ability to confer enhanced and long-lasting protection compared with either infection or vaccination alone. In closing, she highlights the robust T-cell response induced by mRNA vaccines, suggesting that cellular immunity against SARS-CoV-2 remains intact.


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