LAUSR

Key Points Question Do the protein-based SARS-CoV-2 vaccines (FINLAY-FR-2 and FINLAY-FR-1A) provide safe and effective protection against SARS-CoV-2? Findings In this randomized clinical trial including 23 959 individuals, vaccine efficacy for prevention of polymerase chain reaction (PCR)–positive symptomatic COVID-19 was 49.7%; severe disease, 76.8%; and hospitalization, 77.7% after the 2-dose regimen of FINLAY-FR-2, which improved to 64.9% for prevention of PCR-positive symptomatic COVID-19, 96.6% for prevention of severe disease, and 96.6% for prevention of hospitalization in recipients of a 2-dose regimen of FINLAY-FR-2 and a third dose of FINLAY-FR-1A. The incidence of serious adverse events was lower than 0.1%. Meaning The findings of this trial suggest that FINLAY-FR-2, in combination with a third dose of FINLAY-FR-1A, is a safe vaccine inducing a potent immune response against COVID-19.