Oral immunotherapy with inactivated nontypeable Haemophilus influenzae reduces severity of acute exacerbations in...

Acute exacerbations of COPD reflect in part an inappropriate host response to abnormal bacterial colonization. Orally administered inactivated nontypeable Haemophilus influenzae (NTHi) can drive a specific T-cell response that by promoting intrabronchial phagocytosis down-regulates bronchus inflammation.

Subjects with recurrent exacerbations of COPD were studied in a randomized, multicenter, double-blind, placebo-controlled trial, to test efficacy of an NTHi oral immunotherapeutic (HI-164OV). This report describes the outcome in 38 subjects with severe COPD defined as having an FEV(1) < or = 50% of predicted normal.

Exacerbations defined as an increase in volume and purulence of sputum were reduced by 16% (not significant) in the active group. However, moderate-to-severe exacerbations (defined as requiring corticosteroid therapy) were reduced by 63% (P = .05). The proportion with any acute exacerbation was little changed with treatment, but the proportion with episodes requiring corticosteroid therapy was reduced by 56% (P = .07). The mean duration of episodes was reduced by 37% (P = .01) and prescribed courses of antibiotics were reduced by 56% (P = .03) following therapy. Exacerbations requiring admission into hospital were reduced by 90% (P = .04) in the active group. No specific adverse effect was detected.

Treatment of severe COPD with frequent exacerbations with HI-164OV was safe and effective, especially with respect to reduction in parameters of severity.

Australian New Zealand Clinical Trials Registry, www.anzctr.org.au; identifier: ACTRN012606000074594.