Background: Acute exacerbations of chronic obstructive pulmonary disease AECOPD are associated with changes in the sputum microbiome, including an increased prevalence of pathogenic bacteria.
We assessed the efficacy, safety, and immunogenicity of a candidate vaccine containing surface proteins from non-typeable Haemophilus influenzae NTHi and Moraxella catarrhalis Mcat in patients with COPD. Eligible patients were aged years and had a history of at least one moderate or severe exacerbation in the previous year. Patients were allocated using a minimisation algorithm to receive two intramuscular injections of NTHi-Mcat vaccine or placebo 60 days apart, in addition to standard care.
The allocation algorithm considered age category, number of previous exacerbations, COPD severity at study entry, and country as minimisation factors, to guarantee treatment balance within each factor.
Vaccine recipients and those responsible for evaluating study endpoints were masked to group allocation. In the analysis of efficacy, the primary outcome was the rate of any moderate or severe AECOPD occurring within a 1-year period, starting 1 month after the second dose in patients who received two vaccine doses modified total vaccinated cohort. Safety was assessed in the total vaccinated cohort. The trial is registered with ClinicalTrials. Findings: Between Nov 27, , and Nov 30, , adults were enrolled and included in the total vaccinated cohort in the NTHi-Mcat vaccine group, in the placebo group ; received two doses and were included in the primary efficacy analysis in the NTHi-Mcat vaccine group, in the placebo group.
There was one death in the NTHi-Mcat vaccine group acute respiratory failure, not related to vaccination and ten in the placebo group seven due in part to COPD or respiratory failure. Interpretation: NTHi-Mcat vaccine administered to patients with COPD did not show efficacy in reducing the yearly rate of moderate or severe exacerbations.
