Antiviral Drug Favipiravir is a broad-spectrum inhibitor of viral RNA polymerase, an enzyme required for viral replication when human host cells are infected. It is also used to treat Influenza and it has been investigated in other countries to treat novel viruses including Ebola and recently, COVID-19.
ENQUIREThe 2019 coronavirus disease (COVID-19) incidence and mortality are rapidly climbing and the treatment options are limited. There is a need of new therapeutic options but it is limited by a lack of evidence and time required for development. Since there is no licensed treatment that specifically acts against COVID-19, medications such as broad-spectrum antivirals are being studied as experimental adjuncts to supportive care. SARS-CoV-2 and influenza viruses show similar disease presentations and similar organ trophism.
FAVIVIR contains Favipiravir. Favipiravir is a novel antiviral compound that selectively and potently inhibits the RNA dependent RNA polymerase (RdRP) of influenza and many other RNA viruses. It has been found to inhibit all serotypes and strains of influenza A, B and C viruses against which it has been tested, including those resistant to other therapies. Favipiravir is currently the drug under investigation for COVID-19.
Favipiravir is an investigational product and is considered for use in the treatment of coronavirus infection. The Drug Controller General of India (DCGI) has granted an accelerated approval of this drug to meet the urgent medical need for the treatment of COVID-19 through restricted medical use.
Use in the elderly
Since the elderly often have reduced physiological functions, favipiravir should be administered with care to them by monitoring their general conditions under doctors discretion.
Use during Pregnancy, Delivery or Lactation
Do not administer Favipiravir to women known or suspected to be pregnant. (Early embryonic deaths [rats] and teratogenicity [monkeys, mice, rats and rabbits] have been observed in animal studies with exposure levels similar to or lower than the clinical exposure). When administering favipiravir to lactating women, instruct to stop lactating (The major metabolite of favipiravir, a hydroxylated form, was found to be distributed in breast milk).
Pediatric use
Favipiravir has not been administered to children. In a month study with juvenile dogs [8 weeks old], death cases have been reported after day 20 with a dosage [60 mg / kg / day] which was lower than the lethal dosage for young dogs [7 to 8 months old]. In juvenile animals [6-day-old rats and 8-week-old dogs], abnormal gait, atrophy and vacuolation of skeletal muscular fiber, degeneration / necrosis / mineralization of papillary muscle.
Favipiravir should be used with caution with the following drugs
Drugs | Associated risk |
---|---|
Pyrazinamide | Blood uric acid level increases |
Repaglinide | Blood level of repaglinide may increase and adverse reactions to repaglinide may occur |
Theophylline | Blood levels of favipiravir may increase and adverse reactions to favipiravir may occur |
Famciclovir, sulindac | Efficacy of these drugs may be reduced |
Favipiravir has never been administered with the approved dosage. In clinical studies and the global phase III study (studies conducted with dose levels lower than the approved dosage), adverse reactions were observed in 100 of 501 subjects (19.96%) evaluated for the safety (including abnormal laboratory test values). Major adverse reactions included increase of blood uric acid level in 24 subjects (4.79%), diarrhoea in 24 subjects (4.79%), decrease of neutrophil count in 9 subjects (1.80%), increase of AST (GOT) in 9 subjects (1.80%), increase of ALT (GPT) in 8 subjects (1.60%).
Clinically significant adverse reactions
The following clinically significant adverse reactions have been reported with other similar
anti-influenza virus agents, such as, shock, anaphylaxis, pneumonia, hepatitis fulminant,
hepatic
dysfunction, jaundice, toxic epidermal necrolysis (TEN), oculomucocutaneous syndrome
(Stevens-Johnson syndrome), acute kidney injury, white blood cell count decreased, neutrophil
count decreased, platelet count decreased, neurological and psychiatric symptoms (consciousness
disturbed, abnormal behavior, deliria, hallucination, delusion, convulsion, etc.) and colitis
haemorrhagic.
Patients should be carefully monitored, and if any abnormality is observed, the treatment should
be
discontinued and appropriate measures should be taken.
Other adverse reactions
If the following adverse reactions occur, appropriate measures should be taken according to the
symptoms.
≥ 1% | 0.5 - < 1% | < 0.5% | |
---|---|---|---|
Hypersensitivity | Rash | Eczema, pruritus | |
Hepatic | AST (GOT) increased, ALT (GPT) increased, γ-GTP increased | Blood ALP increased, blood bilirubin increased | |
Gastrointestinal | Diarrhoea (4.79%) | Nausea, vomiting, Abdominal pain | Abdominal discomfort, duodenal ulcer, haematochezia, gastritis |
Hematologic | Neutrophil count decreased, white blood cell count decreased | White blood cell count increased, reticulocyte count decreased, monocyte increased | |
Metabolic disorders | Blood uric acid increased (4.79%), Blood triglycerides increased | Glucose urine present | Blood potassium decreased |
Respiratory | Asthma, oropharyngeal pain, rhinitis, nasopharyngitis | ||
Others | Blood CK (CPK) increased, blood urine present, tonsil polyp, pigmentation, dysgeusia, bruise, vision blurred, eye pain, vertigo, supraventricular extrasystoles |
Reporting of suspected adverse reactions
Health care professionals, patients/consumers are advised to closely monitor the possibility of the above ADRs associated with the use of favipiravir. If such reactions are encountered, please report to the Hetero either by filling of Suspect Adverse Drug Reactions Reporting Form (form.heteroworld.com) or by Hetero Helpline No.1800-120-8689 and for all India safety cases and complaints, please write to drugsafetyindia@heterodrugs.com.
It is considered that favipiravir is metabolized in cells to a ribosyl triphosphate form (favipiravir RTP) and that favipiravir RTP selectively inhibits RNA polymerase involved in influenza viral replication. With regards to the activity against human DNA polymerases α, β and γ, favipiravir RTP (1000 μmol/L) showed no inhibitory effect on α, 9.1-13.5% inhibitory effect on β and 11.7-41.2% inhibitory effect on γ. Inhibitory concentration (IC50) of favipiravir RTP on human RNA polymerase II was 905 μmol/L.
No change of susceptibility of type A influenza viruses to favipiravir was observed after 30 passages in the presence of favipiravir, and no resistant viruses have been selected. In clinical studies including the global phase III study, information about emergence of favipiravir-resistant influenza viruses has not been obtained. A polymerases α, β and γ, favipiravir RTP (1000 μmol/L) showed no inhibitory
Blood Concentrations: The following table shows pharmacokinetic parameters of favipiravir after an oral administration in 8 healthy adults at 1600 mg twice daily for 1 day, then 600 mg twice daily for 4 days followed by 600 mg once daily for1 day (1600 mg / 600 mg BID).
Distribution Results in non-Japanese: When favipiravir was orally administered to 20 healthy adult male subjects at 1200 mg twice daily for 1 day followed by 800 mg twice daily for 4 days (1200 mg/800 mg BID), the geometric mean concentration of the drug in semen was 18.341 μg/mL on Day 3, and 0.053 μg/mL on the second day after the treatment. The semen levels became below the limit of quantification (0.02 μg/mL) in all subjects in 7 days after the end of the treatment. The mean ratio of the drug concentration in semen to that in plasma was 0.53 on Day 3 and 0.45 on the second day after the treatment.
Metabolism: Favipiravir was not metabolized by cytochrome P-450 (CYP), mostly metabolized by aldehyde oxidase (AO), and partly metabolized to a hydroxylated form by xanthine oxidase (XO). In studies using human liver microsomes, formation of the hydroxylate ranged from3.98 to 47.6 pmol / mg protein/min, with an inter-individual variation of AO activity by 12 times at maximum. A glucuronate conjugate was observed in human plasma and urine as a metabolite other than the hydroxylated form.
Excretion: Favipiravir was mainly excreted as a hydroxylated form into the urine, and little amount unchanged drug was observed. In an oral 7-day multiple dose study with 6 healthy adults, cumulative urinary excretion ratio of the unchanged drug and the hydroxylated form was 0.8% and 53.1%, respectively, during 48 hours after the last administration.
1# Experimental Treatment with Favipiravir for COVID-19: An Open-Label Control Study
Aim:
Method:
Outcomes:
Results:
Chest CT changes in patients with COVID-19 after treatment
Chest CT changes | COVID-19 patients (N=80) | ||
---|---|---|---|
FPV (N=35) | LVP/RTV (N=45) | P value | |
Day 4 after treatment | |||
Improve | 8 (22.86%) | 8 (17.78%) | 0.42 |
Worse | 9 (25.71%) | 15 (33.33%) | |
Constant | 18 (51.43%) | 22 (48.89%) | |
Day 9 after treatment* | |||
Improve | 18 (56.25%) | 16 (35.55%) | 0.11 |
Worse | 8 (25.00%) | 16 (35.55%) | |
Constant | 6 (18.75%) | 13 (28.90%) | |
Day 14 after treatment | |||
Improve | 32 (91.43%) | 28 (62.22%) | 0.004 |
Worse | 1 (3.23%) | 9 (20.00%) | |
Constant | 2 (6.45%) | 8 (17.78%) |
* For three patients in the FPV arm, the lung CT scan on Days 6-9 after medication was not carried out
Time of viral shedding and improving chest CT scan on Day 14 after treatment
Characteristic | Treatment | ||
---|---|---|---|
FPV (N=35) | LPV/RTV (N=45) | P value | |
Total number of adverse reactions | 4 (11.43%) | 25 (55.56%) | < 0.001 |
Diarrhea | 2 (5.71%) | 5 (11.11%) | 0.46 |
Vomiting | 0 (0%) | 5 (11.11%) | 0.06 |
Nausea | 0 (0%) | 6 (13.33%) | 0.03 |
Rash | 0 (0%) | 4 (8.89%) | 0.13 |
Liver and kidney injury | 1 (2.86%) | 3 (6.67%) | 0.63 |
Others | 1 (2.86%) | 2 (4.44%) | 1.00 |
Conclusion
2# Favipiravir versus Arbidol for COVID-19: A Randomized Clinical Trial
Aim:
To analyse the clinical recovery rate of COVID-19 patients
Method:
Outcome:
Results:
Variables | Favipiravir group | Umifenovir group | Rate ratio (95% CI) | P value |
---|---|---|---|---|
Total patients | (N=116) | (N=120) | ||
Recovered, n (%) | 71 (61.21) | 65 (51.67) | 0.0954 (-0.0305, 0.2213) | 0.1396 |
Moderate patients | (N = 98) | (N = 111) | ||
Recovered, n (%) | 70 (71.43) | 62 (55.86) | 0.1557 (0.0271, 0.2843) | 0.0199 |
Severe or critical patients | (N = 18) | (N = 9) | ||
Recovered, n (%) | 1 (5.56) | 0 (0.00) | 0.0556 (-0.0503, 0.1614) | 0.4712 |
Patients with hypertension and/or diabetes | (N = 42) | (N = 35) | ||
Recovered, n (%) | 23 (54.76) | 18 (51.43) | 0.0333 (-0.1904, 0.2571) | 0.7704 |
Variables | Time to relief for pyrexia | Cough relief time | ||
---|---|---|---|---|
Favipiravir group | Umifenovir group | Favipiravir group | Umifenovir group | |
Total patients | (N = 71) | (N = 74) | (N = 78) | (N = 73) |
Day 1 | 15 (21.13) | 2 (2.70) | 1 (1.28) | 3 (4.11) |
Day 2 | 23 (32.39) | 8 (10.81) | 2 (2.56) | 1 (1.37) |
Day 3 | 19 (26.76) | 18 (24.32) | 23 (29.49) | 7 (9.59) |
Day 4 | 10 (14.08) | 15 (20.27) | 20 (25.64) | 11 (15.07) |
Day 5 | 1 (1.41) | 16 (21.62) | 10 (12.82) | 12 (16.44) |
Day 6 | - | 5 (6.76) | 10 (12.82) | 10 (13.70) |
Day 7 | - | 3 (4.05) | 3 (3.85) | 3 (4.11) |
Day 8 | - | - | 7 (8.97) | 6 (8.22) |
Day 9 | - | - | 1 (1.28) | 3 (4.11) |
Censored | - | - | 1 (1.28) | 17 (23.29) |
Log-rank P value | < 0.0001 | < 0.0001 |
Other secondary outcomes | ||||
---|---|---|---|---|
AOT or NMV* | Favipiravir group | Umifenovir group | Rate ratio (95% CI) | P value |
Total patients | N = 116 | N = 120 | ||
With auxiliary, n (%) | 21 (18.10) | 27 (22.50) | -0.0440 (-0.1464, -0.0585) | 0.4015 |
Patients with hypertension and/or diabetes | N = 42 | N = 35 | ||
With auxiliary, n (%) | 9 (21.43) | 10 (28.57) | -0.0714 (-0.2658, 0.1230) | 0.4691 |
All-cause mortality | 0 (0.00) | 0 (0.00) | / | / |
Dyspnea after taking medicine, n (%) | 4 (3.45) | 14 (11.67) | / | 0.0174 |
Respiratory failure, n (%) | 1 (0.86) | 4 (3.33) | / | 0.3700* |
Comparison of antiviral-associated adverse effects.
Adverse effects | Favipiravir group (N = 116) | Umifenovir group (N = 120) | P value | ||
---|---|---|---|---|---|
Frequency | Cases, n (%) | Frequency | Cases, n (%) | ||
Total | 43 | 37 (31.90) | 33 | 28 (23.33) | 0.1410 |
Abnormal LFT | 10 | 10 (8.62) | 12 | 12 (10.00) | 0.7156 |
Raised serum uric acid | 16 | 16 (13.79) | 3 | 3 (2.50) | 0.0014 |
Psychiatric symptom reactions | 5 | 5 (4.31) | 1 | 1 (0.83) | 0.1149 * |
Digestive tract reactions | 16 | 16 (13.79) | 17 | 14 (11.67) | 0.6239 |
*Fisher’s exact test was used for comparison between groups.
Conclusions:
3# A review of the safety of favipiravir – a potential treatment in the COVID-19 pandemic?
Aim:
To review existing favipiravir safety evidence, which is vital to informing the potential future use of favipiravir in COVI D-19.
Methods:
Results:
Chen at al. | Cai et al | |||
---|---|---|---|---|
Favipiravir | Comparator | Favipiravir | Comparator | |
Grade 1-4 AE | 37/116 (31.9) | 28/120 (23.3) | 4/35 (11.4) | 25/45 (55.6) |
GI AE | 16/116 (13.8) | 14/120 (11.7) | 2/35 (5.7) | 16/45 (35.6) |
LFT elevations | 9/116 (7.8) | 12/120 (10.0) | - | - |
Uric acid elevations | 16/116 (13.8) | 3/120 (2.5) | - | - |
Conclusions:
Reference:
Follow our latest news updates to know about our Favivir.
It is also used to treat Influenza and it has been investigated in other countries to treat novel viruses including Ebola and recently, COVID-19....
It is also used to treat Influenza and it has been investigated in other countries to treat novel viruses including Ebola and recently, COVID-19....
It is also used to treat Influenza and it has been investigated in other countries to treat novel viruses including Ebola and recently, COVID-19....
It is also used to treat Influenza and it has been investigated in other countries to treat novel viruses including Ebola and recently, COVID-19....
It is also used to treat Influenza and it has been investigated in other countries to treat novel viruses including Ebola and recently, COVID-19....
It is also used to treat Influenza and it has been investigated in other countries to treat novel viruses including Ebola and recently, COVID-19....
It is also used to treat Influenza and it has been investigated in other countries to treat novel viruses including Ebola and recently, COVID-19....
It is also used to treat Influenza and it has been investigated in other countries to treat novel viruses including Ebola and recently, COVID-19....
To order or to know more details about Favivir, reach us by filling the form. We will get back you within 1-2 business days.
FAVIVIR, Packaging Information (accessed on: 29/07/2020)
https://www.prnewswire.com/ae/news-releases/rdif-and-chemrar-launch-final-stage-of-favipiravir-clinical-trial-301064181.html (accessed on: 22/05/2020)
Antiviral Drug Favipiravir is a broad-spectrum inhibitor of viral RNA polymerase, an enzyme required for viral replication when human host cells are infected. Favipiravir is effective in preventing viral transcription and replication of RNA polymerase.
Disclaimer: The content mentioned in this website is based on the published literature and is for informational purposes only. Hetero Healthcare makes every effort to present accurate and reliable information, but does not warrant, or assume any legal liability or responsibility for, the accuracy or completeness of any information provided. The product prescribing information complies with drug approval for use in Indian and may not reflect regulatory approvals of other countries. The patient information is not intended to substitute professional advice and services of a qualified healthcare professional. Any advice regarding the management of the medical condition is totally in the discreet of the physician’s knowledge and expertise.
Copyright © All Rights Reserved
by
Hetero Healthcare Limited.