Efficacy trial of live, cold-adapted and inactivated influenza virus vaccines in older adults with chronic obstructive pulmonary disease: a VA cooperative study

We assessed whether trivalent live, cold-adapted influenza virus (CAIV-T) vaccine provides added protection when co-administered with trivalent inactivated influenza virus vaccine (TVV) in patients with chronic obstructive pulmonary disease (COPD). Subjects ( N=2215) were randomly assigned to receive either TVV intramuscularly (IM) and CAIV-T intranasally (TC), or TVV and placebo (TP). The vaccines were well-tolerated. Efficacy of TC compared to TP was not statistically significant and was 0.16 for any influenza virus strain (95% confidence limit (CL): −0.22, 0.43), 0.26 for A (H3N2) virus (95% CL: −0.17, 0.53), and −0.05 for type B virus (95% CL: −1.13, 0.48). However, there was a possible advantage for TC over TP in reducing respiratory consequences of an influenza season measured by pulmonary function and symptoms at end of study.