疫苗的臨床療效指標與免疫橋接在疫苗研發的角色

Efficacy Endpoints and the Role of Immuno-Bridging in Vaccine Development

本文主要介紹研發預防感染症的疫苗時，所選擇的療效指標會因臨床試驗的期別，及試驗目的而有所不同，若為感染症的第1支疫苗，設計良好的疫苗保護力試驗是驗證疫苗療效最直接的方法，但若為同一感染症的後續疫苗，且已有被法規單位認可之抗體效價（替代療效指標）可代表保護力，則樞紐試驗可以使用免疫橋接的設計來驗證疫苗療效，進而取得上市核可。COVID-19的疫情是國際公共衛生緊急事件，醫藥品查驗中心於疫情初始，即積極輔導國內學研單位及廠商，並參與國際上研發COVID-19疫苗之會議，本於法規科學提出以免疫橋接取得國內COVID-19疫苗申請緊急授權製造之標準，並獲得食藥署參採。迄今，先進國家亦已接受使用免疫橋接設計方式取得新COVID-19疫苗的核准。

This article focuses on the consideration of different efficacy endpoints for various phases and purposes of clinical trials when developing vaccines to prevent infectious diseases. If it is the first vaccine for a specific infectious disease, a well-designed vaccine protection trial is the most straightforward method to validate vaccine efficacy. However, if it is a subsequently developed vaccine for the same infectious disease, and the regulatory authorities have recognized the protection represented by antibody titer (surrogate endpoint), then the pivotal trial can use the immuno-bridging design to verify the vaccine efficacy, and then obtain market approval. The outbreak of COVID-19 is an international public health emergency. Since the very beginning of the outbreak, Taiwan Center for Drug Evaluation (CDE) has actively provided consulting services to domestic research institutes and manufacturers, and participated in international conferences on the development of COVID-19 vaccines. Based on solid regulatory science, CDE proposed the technical standards and requirements, adopted by Taiwan Food and Drug Administration (TFDA) for domestic COVID-19 vaccines to obtain Emergency Use Authorization (EUA) by immuno-bridging. To date, advanced countries have also accepted the use of immuno-bridging designs for approval of new COVID-19 vaccines.