This observational study, sponsored by the National Polytechnic Institute in Mexico, aimed to assess the immunogenicity of four COVID-19 vaccines (Oxford/AstraZeneca, Sputnik V, Pfizer/BioNTech, and Sinovac) in the Mexican population. The findings could provide valuable insights into the comparative effectiveness of these vaccines, potentially influencing public health policies and vaccine distribution strategies in Mexico and similar markets. Given the ongoing global focus on COVID-19 vaccination and booster strategies, the results may also have implications for future vaccine development and market positioning. The completion of this study suggests readiness for data dissemination, which could attract interest from pharmaceutical companies and public health organizations looking to enhance vaccine efficacy and safety profiles.