Immunomodulatory Properties of Probiotic Complex ProbioSEB CSC3 in Healthy Adults: A Prospective, Interventional, Randomized, Double-Blinded, Parallel-Group, Placebo-Controlled Clinical Study

Purpose: This study aimed to explore the clinical efficacy and safety of ProbioSEB CSC3 in modulating immune responses. Patients and Methods: A prospective, interventional, randomized, double-blinded, parallel-group, placebo-controlled clinical study was conducted on 88-healthy subjects, divided into probiotic and placebo groups, who received ProbioSEB CSC3 and Maltodextrin, respectively. The primary endpoints were the total Wisconsin Upper Respiratory Symptom Survey (WURSS) score, overall severity of URTI symptoms, immunological parameters, and serum cortisol levels. The secondary endpoints were vital physical, hematological and biochemical parameters, adverse and/or serious adverse events (AEs/SAEs), tolerability, and Quality of Life (QoL). Results: ProbioSEB CSC3 improved the WURSS and overall severity of the URTI symptom scores post-intervention. A significant improvement in the overall distribution of the illness duration (total symptom days/subject) was observed with probiotic intake compared to placebo (p=0.048,Log rank test). Furthermore, ProbioSEB CSC3 significantly improved immunoglobulin (Ig)-G, Ig-A, interferon-gamma (IFN-γ), interleukin (IL)-10, C-reactive protein (CRP), and cortisol levels ( p < 0.01). The overall QoL of the subjects in the probiotic group significantly improved ( p < 0.01). No AEs or SAEs leading to termination of the study were reported. Conclusion: ProbioSEB CSC3 supplementation positively modulated the immune response and demonstrated efficacy against URTI and/or alleviated associated symptoms. The administered dose was well tolerated and found to be safe. Further clinical studies on larger populations, multiple centers, and prolonged intervention periods are necessary to validate the results and prophylactic role of probiotics in immunomodulation.