Real-world effectiveness of NVX-CoV2373 and BNT162b2 mRNA COVID-19 vaccination in South Korea.

OBJECTIVES

In February 2022, NVX-CoV2373 became available in South Korea; real-world effectiveness of multiple doses compared with mRNA-based vaccines has not been thoroughly evaluated.

METHODS

This retrospective study identified NVX-CoV2373 and BNT162b2 recipients aged ≥12 years from the K-COV-N database. Vaccine groups were propensity score-matched based on demographic characteristics, Seoul capital area residence, income level, comorbidity/disability, prior SARS-CoV-2 infection, and prior vaccination dose/timing. Outcomes were any and severe (intensive-care-unit admission or death within 8 weeks of infection) laboratory-confirmed SARS-CoV-2 infection assessed from 7 days after the third and fourth dose. Adjusted hazard ratios (aHRs) from matched groups measured vaccine effectiveness up to a 180-day risk window.

RESULTS

From February to December 2022, 923,833 NVX-CoV2373 and 1,286,604 BNT162b2 doses were administered. The 180-day risk-window aHRs (95% CI) for NVX-CoV2373 compared with BNT162b2 for any SARS-CoV-2 infection were 0.78 (0.76-0.79) post third dose and 0.86 (0.86-0.87) post fourth dose. The 180-day aHRs (95% CI) for severe infection were 0.73 (0.53-1.00) after the third dose and 1.21 (1.03-1.42) after the fourth dose.

CONCLUSIONS

NVX-CoV2373 demonstrated favorable and similar effectiveness against any and severe SARS-CoV-2 infection, respectively, compared with BNT162b2, with evidence of enhanced NVX-CoV2373 durability.