Favipiravir for COVID-19: real-time meta-analysis of 74 studies (Version 89)

Significantly lower risk is seen for recovery and viral clearance. 32 studies from 32 independent teams in 16 countries show significant benefit.

Meta-analysis using the most serious outcome reported shows 11% [3‑18%] lower risk. Results are similar for Randomized Controlled Trials, higher quality studies, and peer-reviewed studies. Studies to date show no significant difference for mortality. A small mortality improvement is seen, without statistical significance, however meta regression with followup duration shows decreasing efficacy with longer followup. There is also no benefit seen for mechanical ventilation, ICU admission, or hospitalization. This may reflect antiviral efficacy being offset by side effects of treatment.

2 RCTs with 1,128 patients have not reported results (up to 4 years late)1,2.

Potential risks include kidney injury3-5, liver injury4-7, cardiovascular toxicity7,8, pulmonary toxicity8,9, and mutagenicity, carcinogenicity, teratogenicity, embryotoxicity, and the creation of dangerous variants10-16. Favipiravir may impair clotting17. Variants may be less susceptible to favipiravir18.

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.