Adverse effects associated with favipiravir in patients with COVID-19 pneumonia: a retrospective study

ABSTRACT BACKGROUND: Favipiravir is generally used in treating coronavirus disease 2019 (COVID-19) pneumonia in Turkey. OBJECTIVE: To determine the side effects of favipiravir and whether it is a good treatment option. DESIGN AND SETTING: Retrospective study conducted in Atatürk Chest Diseases and Chest Surgery Training and Research Hospital, Ankara, Turkey. METHODS: 357 patients who completed favipiravir treatment at the recommended dose were included. 37 patients with drug side effects and 320 patients without drug side effects were examined in two groups. RESULTS: Side effects were observed in 37 (10.36%) out of 357 patients using favipiravir. The most common side effect was liver dysfunction, in 26 (7.28%) of the patients. The following other side effects were also observed: diarrhea (1.4%), nausea (0.84%), abdominal pain (0.28%) and thrombocytopenia (0.28%). One patient (0.28%) presented both increased transaminases and nausea. CONCLUSION: In this study, it was determined that favipiravir may constitute an alternative for treating COVID-19 pneumonia given that its side effects are generally well tolerated and not serious.

Favipiravir and its potentials in COVID-19 pandemic: An update

The COVID-19 pandemic has caused millions of deaths and hundreds of millions of confirmed infections worldwide. This pandemic has prompted researchers to produce medications or vaccines to reduce or stop the progression and spread of this disease. A variety of previously licensed and marketed medications are being tested for the treatment and recurrence of SARS-CoV2, including favipiravir (Avigan). Favipiravir was recognized as an influenza antiviral drug in Japan in 2014, and has been known to have a potential in vitro activity against SARS-CoV-2, in addition to its broad therapeutic safety scope. Favipiravir was recently approved and officially used in many countries worldwide. Our review provides insights and up-to-date knowledge of the current role of favipiravir in the treatment of COVID-19 infection, focusing on preclinical and ongoing clinical trials, evidence of its efficacy against SARS-CoV-2 in COVID-19, side effects, anti-viral mechanism, and the pharmacokinetic properties of the drug in the treatment of COVID-19. Due to its teratogenic effects, favipiravir cannot be offered to expectant or pregnant mothers. The practical efficacy of such an intervention regimen will depend on its dose, treatment duration, and cost as well as difficulties in application.