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 follow-up duration shows decreasing efficacy with longer follow-up. 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 5 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.