Bacterial lysates as a potentially effective approach in preventing acute exacerbation of COPD.

The use of bacterial lysates to reduce acute exacerbations of COPD (AECOPDs) is an intriguing concept. Bacterial lysates are powerful inducers of a specific immune response against bacterial infections, but their mechanism of action is not fully understood. Apparently, they lower bacterial carriage levels in the respiratory tract, decrease the incidence and severity of exacerbations, decrease hospitalizations owing to exacerbations, and reduce the need for antibiotics. Unfortunately, almost all trials conducted to date are small and methodologically flawed. Further studies are needed to produce a greater level of evidence that can support the recommendation for a more widely use of bacterial lysates as a prophylactic treatment of AECOPDs.