Metformin reduces COVID-19 risk: real-time meta-analysis of 110 studies (Version 99)

Significantly lower risk is seen for mortality, ventilation, ICU admission, hospitalization, progression, recovery, and viral clearance. 72 studies from 66 independent teams in 22 countries show significant benefit.

Meta-analysis using the most serious outcome reported shows 32% [28‑35%] lower risk. Results are similar for Randomized Controlled Trials, higher quality studies, and peer-reviewed studies.

Results are very robust—in worst case exclusion sensitivity analysis 86 of 110 studies must be excluded before statistical significance is lost. Emergent results for the efficacy gradient across outcomes (p < 0.0000001) that match the biological mechanisms confirm efficacy.

Control Metformin

Most studies analyze existing use with diabetic patients. Prophylaxis results typically include continuing use after infection and hospitalization, and greater benefit is seen for more serious outcomes. The TOGETHER RCT shows 27% lower mortality. While not statistically significant, p = 0.53, this is consistent with the mortality results from all studies, 36% [32‑40%].

No treatment is 100% effective. Protocols combine safe and effective options with individual risk/benefit analysis and monitoring. Other treatments are more effective. All data and sources to reproduce this analysis are in the appendix.

24 other meta-analyses show significant improvements with metformin for mortality1-23, hospitalization7,13,23, progression1, severity8,9,13, and long COVID23.

24 meta-analyses show significant improvements with metformin for mortality1-23, hospitalization7,13,23, progression1, and severity8,9,13.