Oral Bacterial Lysate OM-85 Prevents Respiratory Tract Infections in Asthma: The OMRIA RWE Study

Maria Elpida Christopoulou,1,2 Lilia S Panteli,1 John A Moisidis,1 Ioannis A Christopoulos,3 Maria Eleni Kasimeri,4 Amalia S Tryphonidou,1 Antonios I Christopoulos1,3 1Asthma Clinics, Primary Care Clinics for Asthma, Allergy & Respiratory Health Athens, Patras, Kalavryta, Greece; 2Clinic of Pneumology, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany; 3Department of Respiratory Medicine, University General Hospital, Faculty of Medicine, University of Patras, Patras, Greece; 4Mid Yorkshire Teaching NHS Trust, Pinderfields Hospital, Wakefield, West Yorkshire, UKCorrespondence: Maria Elpida Christopoulou, Email [email protected] Antonios I Christopoulos, Email [email protected]: OM-85 is a well-characterized bacterial lysate with antiviral properties, enhancement of airway epithelial barrier function, and tolerance induction. However, real-world evidence is needed to evaluate its effectiveness as an add-on therapy in patients with allergic asthma.Methods: This retrospective cohort study analyzed medical records of 137 adults with moderate to severe allergic asthma over 12 months. Patients receiving standard of care (SoC) asthma therapy alone (GINA step 4, n = 67) were compared to those on SoC+OM-85 (n = 70). All symptom episodes (CEPs) indicative of respiratory tract infections (RTIs) were recorded, and a 3-scale mean severity index (mSI) was calculated. Propensity score weighting was used for Poisson and linear regression analyses.Results: Patients on OM-85 demonstrated significant reductions in the number of CEPs (60%), asthma exacerbations (71%), unscheduled visits (72%), oral corticosteroid courses (73%), and antibiotic cycles (67%). The mSI was 1.15 points lower in the OM-85 group (p < 0.001).Conclusion: OM-85 as an add-on to standard asthma therapy significantly reduced RTI-related episodes, exacerbations, and healthcare utilization while lowering symptom severity in adults with allergic asthma.Keywords: OM-85, allergic asthma, human rhinovirus (HRV), HRV, bacterial lysates, asthma exacerbations, immunomodulation