RT Journal Article T1 An Updated Review of SARS-CoV-2 Vaccines and the Importance of Effective Vaccination Programs in Pandemic Times A1 García Montero, Cielo A1 Fraile Martínez, Oscar A1 Bravo Arribas, Coral A1 Torres Carranza, Diego A1 Sanchez Trujillo, Lara A1 Gómez Lahoz, Ana M. A1 Guijarro, Luis G. A1 García Honduvilla, Natalio A1 Asúnsolo, Angel A1 Bujan, Julia A1 Monserrat, Jorge A1 Serrano, Encarnación A1 Álvarez Mon, Melchor A1 De León Luis, Juan Antonio A1 Alvarez Mon, Miguel Ángel A1 Ortega, Miguel A. AB Since the worldwide COVID-19 pandemic was declared a year ago, the search for vaccines has become the top priority in order to restore normalcy after 2.5 million deaths worldwide, overloaded sanitary systems, and a huge economic burden. Vaccine development has represented a step towards the desired herd immunity in a short period of time, owing to a high level of investment, the focus of researchers, and the urge for the authorization of the faster administration of vaccines. Nevertheless, this objective may only be achieved by pursuing effective strategies and policies in various countries worldwide. In the present review, some aspects involved in accomplishing a successful vaccination program are addressed, in addition to the importance of vaccination in a pandemic in the face of unwillingness, conspiracy theories, or a lack of information among the public. Moreover, we provide some updated points related to the landscape of the clinical development of vaccine candidates, specifically, the top five vaccines that are already being assessed in Phase IV clinical trials (BNT162b2, mRNA-1273, AZD1222, Ad26.COV2.S, and CoronaVac). PB MDPI SN 2076-393X YR 2021 FD 2021-04-27 LK https://hdl.handle.net/20.500.14352/7399 UL https://hdl.handle.net/20.500.14352/7399 LA eng NO García-Montero C, Fraile-Martínez O, Bravo C, Torres-Carranza D, Sanchez-Trujillo L, Gómez-Lahoz AM, et al. An Updated Review of SARS-CoV-2 Vaccines and the Importance of Effective Vaccination Programs in Pandemic Times. Vaccines 2021;9:433. https://doi.org/10.3390/vaccines9050433. NO This work was partially supported by grants from the Fondo de Investigación de la Seguridad Social, Instituto de Salud Carlos III (PI18/00912), Spain; Programa de Actividades de I+D de la Comunidad de Madrid en Biomedicina (B2017/BMD3804), Madrid, Spain; and Instituto de Salud Carlos III CIBER Enfermedades hepáticas y Digestivas, Spain. NO Comunidad de Madrid NO Instituto de Salud Carlos III DS Docta Complutense RD 16 dic 2025