As the COVID-19 pandemic continues to evolve, the importance of booster doses in protecting against severe illness has become increasingly clear. A recent study published in Vaccine compared the real-world effectiveness of a third dose of two popular mRNA vaccines: mRNA-1273 (Moderna) and BNT162b2 (Pfizer-BioNTech). The focus was on preventing breakthrough COVID-19 hospitalizations among adults aged 65 and older who had completed a primary series of an mRNA-based COVID-19 vaccine.
Study Overview
This observational study analyzed data from the US HealthVerity database, covering the period from September 22, 2021, to August 31, 2022. It assessed the effectiveness of a third dose of mRNA-1273 versus BNT162b2 in preventing COVID-19 hospitalizations and medically attended COVID-19 cases in adults aged 65 and above. The researchers used inverse probability of treatment weighting to ensure that baseline characteristics between the two vaccine groups were balanced.
This study provides compelling evidence that, among older adults, a third dose of mRNA-1273 is more effective in preventing both breakthrough COVID-19 hospitalizations and medically attended COVID-19 cases compared to a third dose of BNT162b2. These findings can help inform vaccine policy and booster dose recommendations, particularly for older populations at higher risk of severe outcomes.