An efficacious COVID-19 vaccine is the world’s leading research priority [1]. In response to the ongoing pandemic, the World Health Organization (WHO) has fast-tracked medical products for COVID-19 treatment onto the public market through emergency use listings [2]. These emergency authorizations have compressed the usual 10-15 years for vaccine research and development to 1-2 years largely due to joint efforts globally and an existing research foundation for vaccine development [4].

Conventionally, conducting double-blind, placebo-controlled, randomized trials to determine efficacy against clinically relevant, predefined markers is considered the gold-standard approach to develop trustworthy data for vaccine licensing and policy decisions [1]. Given the urgency of the pandemic, several nations have stated that if there was a compelling case for use of a vaccine before it was licensed, they would be prepared to authorize its emergency use [1].

The WHO utilizes these listings to assess the suitability of novel health products during public health emergencies, like the COVID-19 pandemic [2]. This type of authorization allows the use of unapproved medical products to diagnose, treat, or prevent serious disease in response to a declared public health emergency for which there are no adequate alternatives [6]. The goal is to make medicines, vaccines, and diagnostics available as rapidly as possible to address the public health crisis, while also adhering to strict criteria of safety, efficacy, and quality [2].

The submission of an emergency use listing of a vaccine must follow a specific format [6]. The vaccine manufacturer must apply to the WHO with key information including (1) manufacturing quality data, (2) non-clinical and clinical data, (3) a plan to track safety, efficacy, and quality, and (4) labelling details [6]. To approve a COVID-19 vaccine for emergency use, the WHO requires rigorous assessment of late phase II and phase III clinical trial data [2]. The vaccine must have been manufactured in compliance with current Good Manufacturing Practices, and the company producing the vaccine must commit to continue to produce data to enable full licensure and WHO prequalification of the vaccine [2,6]. The WHO prequalification process then assesses additional clinical data generated from the vaccine trials and deployment on a rolling basis to ensure the vaccine meets necessary standards of safety, efficacy, and quality [2].

Additionally, the process of approving a vaccine involves the Strategic Advisory Group of Experts (SAGE), the principal advisory group to the WHO for vaccines and immunization [3]. SAGE and the WHO’s emergency use listing process are complementary but independent entities [3].

In October 2020, the WHO proposed draft guidelines requiring 3 months of efficacy follow-up data before a vaccine could be considered for its emergency use listing [5]. The first COVID-19 vaccine to be approved by the WHO in this manner was the Pfizer-BioNTech vaccine on December 31, 2020 [2]. Soon after, the WHO listed the AstraZeneca-SK Bio, Serum Institute of India, Janssen (Johnson & Johnson), and Moderna vaccines [2]. At present, there are 19 vaccines available for emergency use according to the WHO [4].

References 

1. Singh, J., & Upshur, R. (2020). The granting of emergency use designation to COVID-19 candidate vaccines: implications for COVID-19 vaccine trials. The Lancet Infectious Diseases. doi:10.1016/S1473-3099(20)30923-3 
2. WHO lists additional COVID-19 vaccine for emergency use and issues interim policy recommendations. (2021). https://www.who.int/news/item/07-05-2021-who-lists-additional-covid-19-vaccine-for-emergency-use-and-issues-interim-policy-recommendations 
3. WHO validates Sinovac COVID-19 vaccine for emergency use and issues interim policy recommendations. (2021). https://www.who.int/news/item/01-06-2021-who-validates-sinovac-covid-19-vaccine-for-emergency-use-and-issues-interim-policy-recommendations 
4. Cui, X., Wang, P., Wei, Z. (2021). Emergency use of COVID-19 vaccines recommended by the World Health Organization (WHO) as of June 2021. Drug Discoveries & Therapeutics. doi:10.5582/ddt.2021.01064 
5. Krause, P. R., & Gruber, M. F. (2020). Emergency use authorization of Covid vaccines—safety and efficacy follow-up considerations. New England Journal of Medicine, 383(19), e107. doi:10.1056/NEJMp2031373 
6. Emergency Use Listing Procedure for vaccines. (2021). https://www.who.int/teams/regulation-prequalification/eul/eul-vaccines