A real-world study of more than 8,800 vaccinated patients has found that a single dose of Johnson & Johnson’s COVID-19 vaccine is 74% effective.
The results come from an analysis of Mayo Clinic patients’ electronic health records and mirror the findings of the company’s original clinical drug trials. These showed that the vaccine had 67% efficacy against moderate-to-severe COVID-19 that starts at least 14 days after vaccination.
The current study also shows that the J&J vaccine retains protectiveness in the face of the widely circulating alpha and delta gene variants, reported investigators from the Mayo Clinic. These variants were not prevalent at the time of the clinical trials, they said.
The analysis linked vaccination with the J&J drug to an overall reduction in severe cases, and hospitalization in particular. Investigators were not able to determine the drug’s effect on mortality, however, as only 60 of the 8,889 vaccinated participants contracted COVID-19 after getting the shot, they said.
Full findings were published in JAMA Network Open.
