Late Breaking Abstract - First-time assessment of efficacy of candidate vaccine to prevent acute exacerbations of chronic obstructive pulmonary disease (AECOPD): multicentre, randomised, controlled, observer-blind phase 2b trial

Abstract

Background: Vaccination against the most frequent bacteria associated with AECOPD may reduce exacerbation frequency.

Aim: To assess the efficacy, safety and immunogenicity of a candidate vaccine containing non-typeable Haemophilus influenzae (NTHi) and Moraxella catarrhalis (Mcat) surface proteins in patients with COPD (NCT03281876).

Methods: COPD patients with stable, moderate to very severe airflow limitation (GOLD 2–4) and history of exacerbations received 2 NTHi-Mcat vaccine or placebo injections 60 days apart. Primary outcome was rate of moderate/severe exacerbations during 1 year starting 1 month after 2-dose vaccination.

Results: Yearly rate of moderate/severe exacerbations was 1.22 in vaccine group (279 patients) and 1.17 in placebo group (292 patients) (vaccine efficacy [VE] estimate -2.26%; 87% CI -18.27 to 11.58; p=0.82). VE estimate for severe exacerbations was 36.54% (95% CI -4.69 to 61.53; p=0.08). There were 55 reports of COPD leading to hospitalisation in vaccine group and 82 reports in placebo group. One death was reported in vaccine group (respiratory failure; unrelated to vaccine) and 10 in placebo group (7 with respiratory cause). Few severe adverse events (AEs) and no vaccine-related serious AEs were reported. Antigen-specific antibody levels increased after each vaccine dose.

Conclusions: NTHi-Mcat vaccine administered to patients with COPD was immunogenic but did not reduce the yearly rate of moderate/severe exacerbations. No safety concerns were identified. There were fewer reports of COPD leading to hospitalisation in the vaccine group.

Funding: GSK