The DANFLU-2 study evaluated the effectiveness of high-dose influenza vaccine in 332,438 older adults with a mean age of 73.7 years.[1] Participants were randomly divided into two groups - one receiving a high-dose vaccine and the other a standard dose.[1] The primary study endpoint was hospitalization for influenza or pneumonia, which occurred in 0.68% of participants in the high-dose group and 0.73% in the standard-dose group, a difference without statistical significance.[1] However, the high-dose vaccine demonstrated higher efficacy in influenza-specific hospitalizations—43.6% relative vaccine efficacy.[1] All-cause hospitalizations were similar in both groups (9.38% vs. 9.58%), and all-cause deaths were also no different.[1] Side effects were similar in both groups.[1] The study concluded that the high-dose flu vaccine did not reduce hospitalizations for flu or pneumonia more significantly than the standard dose in older adults.[1]