ABSTRACT
BACKGROUND Targeting mucosal immunity of the gut, which is known to provide antigen processing, while avoiding excessive or unnecessary inflammation, was tested as a way to modulate Covid-19 severity. METHODS Randomized open-label trial in 204 adults hospitalized with non-critical Covid-19 who received for 14 days in addition to standard of care (SOC) degalactosylated bovine glycoproteins formulations of either MAF Capsules (MAF group) or M Capsules (M group) or SOC only (control group). RESULTS Median recovery time when patients did not require supplemental oxygen was 6 days in both study groups compared to 9 days in the control (MAF vs. control; P=0.020 and M vs. control; P=0.004). A greater reduction in mortality was seen in the MAF group compared to the control by day 14 (8.3% vs. 1.6%; P=0.121) and by day 29 (15.3% vs. 3.2%; P=0.020), and similarly in the M group by day 14 (8.3% vs. 2.9%; P=0.276) and by day 29 (15.3% vs. 2.9%; P=0.017). The proportion of those who had baseline absolute lymphocyte count (ALC) lower than 0.8x10^9/L was 13/63 (20.6%), 17/69 (27.0%), and 18/72 (25.0%) of patients in MAF, M, and control group respectively. Day 29 mortality among these lymphopenic patients was three times higher than for the intent-to-treat population (21% vs. 7%) and consisted in above subgroups: 2/13 (15%), 2/17 (12%), and 6/18 (33%) of patients. There showed decreased mortality in both study subgroups correlated with greater ALC restoration above 0.8x109/L level seen on day 14 in 77% and 59% of patients in MAF and M subgroups respectively compared to 22% of patients in control subgroup. Incidences of any ALC decrease below the baseline level on day 14 occurred in 25.4% of patients in the MAF group and 29.0% of patients in the M group compared to 45.8% in control and ALC depletion by ≥50% from the baseline level consisted of 7.9%, 5.8%, and 15.3% of cases in these groups respectively. CONCLUSION This study showed that both study agents prevented ALC depletion and accelerated its restoration, which is believed one of the mechanisms of improved crucial clinical outcomes in hospitalized Covid-19 patients. Trial registration: ClinicalTrials.gov NCT04762628, https://www.clinicaltrials.gov/ct2/show/NCT04762628.