Clinical Trial Data on the Use of Probiotics in Outpatients With COVID-19

Researchers at the Hospital General Manuel Gea González in Mexico City have reported results from a study designed to assess the impact of four specific strains of probiotics on the rate of remission from infection with SARS-CoV-2, the virus that causes COVID-19. The study investigated the effects of a one-a-day probiotic or placebo capsule over a 30-day period in confirmed adult COVID-19 patients with mild symptoms, but not hospitalized.

The placebo-controlled, double-blinded clinical trial randomized 300 patients aged 18-60 with PCR-confirmed COVID-19 and mild symptoms. The impact of the combination of four specific probiotic strains shows significant results on remission rate, duration of symptoms, and viral load (as measured by RT-PCR), while no ICU admissions were observed during the study period. There was no adverse event noted associated with the probiotics strain blend.

Detailed efficacy and safety results are being submitted for peer review and will address the following parameters:

– remission rate, as measured by both the absence of COVID-19 symptoms and a negative RT-PCR test
– reduction in the number of symptomatic patients with COVID-19
– reduction in the duration of specific symptoms
– reduced viral load in nasopharyngeal swabs
– increased specific IgG and IgM levels against SARS-CoV-2

Investigating the Gut-Lung Axis in COVID-19 Patients

The hypothesis of this clinical study was based on the commonly defined gut-lung axis, the cross-talk between intestinal and pulmonary tissues. Mediated by the microbiome and immune cells, it has demonstrated its importance in certain respiratory diseases.  With 75% of the immune system being associated with gut cells, the gut microbiota has been shown to be significantly involved in regulating the development and function of the immune system.

One in three patients afflicted with COVID-19 present dysbiosis and patients with gastrointestinal symptoms had increased severity of the disease, thus making the microbiota a potential therapeutic target to study for the management and transmission of COVID-19.

Lead investigator Pedro Gutierrez-Castrellon, MD, said “The preliminary results of this clinical trial are encouraging, and we are extremely excited to have been a part of such timely research. Further research is needed to corroborate and explore additional benefits; however, it’s important to note that probiotics are well known for their health benefits on the host, when administered in adequate amounts. As stated by the WHO, they require well-designed clinical trials to be considered as such, and their benefits are strictly strain-specific, therefore positive evidence in a clinical trial for a particular health condition, efficacy cannot be extrapolated or extended to other strains without clinical evidence.”

The specific probiotic strains used in this study L. Plantarum KABP-033, L. Plantarum KABP-022, L. Plantarum KABP-023, P. Acidilactici KABP-021 were supplied by AB-Biotics, a subsidiary of Kaneka Corporation.

The General Hospital Dr. Manuel Gea González is a decentralized public body based in Mexico DF, belonging to the Coordination of National Institutes of Health and High Specialty Hospitals, which provides quality medical services focused on prevention, treatment and rehabilitation, and the training of human talent excellence as well as innovative research.