In responding to the necessity of emergency public health circumstances, Taiwan FDA (TFDA) may approve to manufacture and import the COVID-19 vaccines as special cases based on Article 48-2 of the Pharmaceutical Affairs Act (藥事法). In June 2021, TFDA announced the standards in granting EUA for COVID-19 vaccines to prevent COVID-19 public health emergency. The criteria focus on evaluating a vaccine candidate's quality, safety and efficacy. In terms of safety, the number of clinical trial participants and follow-up monitoring plan must comply with the requirements. The vaccine efficacy can be analyzed via a surrogate approach called immuno-bridging, which allows to infer the overall level of protection the vaccine provides by comparing the immune response (neutralizing antibodies) created in the body by the vaccine candidate, to the immune response elicited by the approved vaccines.

EUA requests are evaluated based on the scientific evidence such as clinical, pre-clinical, and Chemistry, Manufacturing and Controls (CMC) data. To date, TFDA has issued 3 imported COVID-19 vaccines, AstraZeneca (AZ), Moderna and Pfizer-BioNTech, and a domestically developed vaccine manufactured by Medigen Vaccine Biologics Corp. Medigen vaccine trial results met the EUA standards announced in June 2021 and it is the first protein-based COVID-19 vaccine to be made available in Taiwan.