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 15% [5‑24%] 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 3 years late)1,2.
Potential risks include the creation of dangerous variants, and mutagenicity, carcinogenicity, teratogenicity, and embryotoxicity3-7. Favipiravir may impair clotting8. Variants may be less susceptible to favipiravir9.
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.
Covid Analysis et al., Jan 2025, preprint, 1 author.
