Oral Probiotic Containing Streptococcus salivarius K12 and Lactobacillus brevis CD2 for Preventing Bacterial Pneumonia in Severe COVID-19: Randomized Clinical Trial.

The incidence of secondary bacterial pneumonia was lower in the probiotic group than placebo, but the difference was not statistically significant.

• Secondary bacterial pneumonia incidence was 35% for probiotics and 54% for placebo.
• Relative risk: 0.64 (95% CI: 0.34–1.22), indicating the confidence interval crossed 1.0.
• 50 patients completed the 7-day experiment out of 60 randomized.
• Probiotic group: 26 patients (mean age 58.7 years, 81% men); placebo group: 24 patients (mean age 60.5 years, 71% men).

ICU mortality did not differ significantly between the probiotic and placebo groups.

• Hazard ratio for ICU death with probiotics compared to placebo: 1.37 (95% CI: 0.56–3.35).
• The confidence interval crossed 1.0, indicating no statistically significant difference in survival.
• Survival was a pre-specified secondary outcome.

The 14-day illness-severity status did not differ between the probiotic and placebo groups.

• 14-day illness-severity status was a pre-specified secondary outcome.
• No statistically significant difference was observed between groups.
• This was assessed across both the probiotic group (n=26) and placebo group (n=24).

The trial used a randomized, placebo-controlled design with dental application of oral probiotic gel in ICU patients with severe COVID-19.

• 60 patients with severe COVID-19 were randomly assigned to probiotic or placebo.
• The probiotic gel contained S. salivarius K12 (2 billion CFU) and L. brevis CD2 (4 billion CFU), administered every 8 hours for 7 days.
• Gel applications were performed by a dentist, starting on the first ICU day.
• This was described as a phase II trial.

ICU patients with COVID-19 are prone to secondary bacterial pneumonia, providing the rationale for testing oral probiotics targeting oral pathogens as a preventive strategy.

• The hypothesis was that probiotics against oral pathogens might prevent lung colonization and avoid pneumonia.
• The primary outcome was specifically secondary bacterial pneumonia.
• The study targeted oral microbiome modulation via dental application as the mechanistic pathway.