OVERVIEW OF FAVIPIRAVIR AND REMDESIVIR TREATMENT FOR COVID-19

Abstract

The current coronavirus disease 2019 (COVID-19)
outbreak caused by severe acute respiratory syndrome coronavirus 2
(SARS-CoV-2) emerged in the wholesale market in Wuhan, China in the
last months of 2019 and spread to almost all countries of the world.
Although several vaccines have already been developed in different
countries of the world, there is currently no specific treatment for
COVID-19. Some agents are used all over the world based on in-vitro, invivo studies, and randomized controlled studies. The number of studies on
antiviral therapy has been increasing day by day. However, the efficacy
of antiviral drugs for COVID-19 remains controversial. In this review,
brief information about antiviral drugs favipiravir and remdesivir used for
the treatment of COVID-19, the results of the conducted studies, and the
possible adverse effects of these drugs are summarized. We hope that this
review will provide an impression of favipiravir and remdesivir used to
treat and control COVID-19 patients until the approval of specific drugs
that target SARS-CoV-2.

Full text

Eroglu and Toprak, IJPSR, 2021; Vol. 12(4): 1950-1957. E-ISSN: 0975-8232; P-ISSN: 2320-5148
International Journal of Pharmaceutical Sciences and Research 1950
IJPSR (2021), Volume 12, Issue 4 (Review Article)
Received on 25 January 2021; received in revised form, 02 March 2021; accepted, 21 March 2021; published 01 April 2021
OVERVIEW OF FAVIPIRAVIR AND REMDESIVIR TREATMENT FOR COVID-19
Ezgi Eroglu * 1 and Cigdem Toprak 2
Department of Pharmacology 1, Faculty of Pharmacy, Lokman Hekim University, 06530, Ankara, Turkey.
Department of Anesthesia 2, Vocational School of Health Services, Bursa Uludag University, 16240,
Bursa, Turkey.
ABSTRACT: The current coronavirus disease 2019 (COVID-19)
outbreak caused by severe acute respiratory syndrome coronavirus 2
(SARS-CoV-2) emerged in the wholesale market in Wuhan, China in the
last months of 2019 and spread to almost all countries of the world.
Although several vaccines have already been developed in different
countries of the world, there is currently no specific treatment for
COVID-19. Some agents are used all over the world based on in-vitro, in-
vivo studies, and randomized controlled studies. The number of studies on
antiviral therapy has been increasing day by day. However, the efficacy
of antiviral drugs for COVID-19 remains controversial. In this review,
brief information about antiviral drugs favipiravir and remdesivir used for
the treatment of COVID-19, the results of the conducted studies, and the
possible adverse effects of these drugs are summarized. We hope that this
review will provide an impression of favipiravir and remdesivir used to
treat and control COVID-19 patients until the approval of specific drugs
that target SARS-CoV-2.
INTRODUCTION: Severe acute respiratory
syndrome coronavirus-2 (SARS-CoV-2) is the
main factor of coronavirus disease 2019 (COVID-
19) announced a global epidemic by the World
Health Organization (WHO) on March 11, 2020 1.
SARS-CoV-2 first appeared in Wuhan, China in
December 2019. The source of the virus was
initially unknown, but it was later discovered that
newly diagnosed cases were linked to the Huanan
Seafood Wholesale Market, where people could
buy wild animals such as bats 2. After the first
cases emerged in China, the virus is known to
spread rapidly throughout the world 3.
QUICK RESPONSE CODE
DOI:
10.13040/IJPSR.0975-8232.12(4).1950-57
This article can be accessed online on
www.ijpsr.com
DOI link: http://dx.doi.org/10.13040/IJPSR.0975-8232.12(4).1950-57
SARS-CoV-2 has been reported to have
phylogenetic similarity with the severe acute
respiratory syndrome coronavirus (SARS-CoV)
and the Middle East respiratory syndrome
coronavirus (MERS-CoV) 4. SARS-CoV-2 is
associated with human SARS-CoV showing 82%
nucleotide similarity 5. Early studies on COVID-19
have reported that SARS-CoV-2 may be
transmitted from animal to human by droplets or
from person to person by direct contact 6.
In addition, SARS-CoV-2 has been reported to be
transmitted from human angiotensin. Studies have
also shown that it encodes the spike S protein,
which allows binding to transforming enzyme 2
(ACE2), and by supporting the membrane fusion of
this protein, it enables the virus to enter human
cells such as the lung by endocytosis. After
entering human cells, SARS-CoV-2 uses the
protein synthesis mechanism of human cells to
Keywords:
COVID-19, Coronavirus, SARS-CoV-
2, Favipiravir, Remdesivir
Correspondence to Author:
Ezgi Eroglu
Assistant Professor ,
Department of Pharmacology,
Faculty of Pharmacy, Lokman Hekim
University, 06530, Ankara, Turkey.
E-mail: ezgbzkrt@gmail.com

Eroglu and Toprak, IJPSR, 2021; Vol. 12(4): 1950-1957. E-ISSN: 0975-8232; P-ISSN: 2320-5148
International Journal of Pharmaceutical Sciences and Research 1951
synthesize viral proteins and subsequently provide
viral replication 7. Once in the human body, viruses
generally trigger a range of responses, such as
autophagy, apoptosis, and stress response 8.
Approximately 20% of individuals infected with
SARS-CoV-2 who suffer from health problems
such as lung disease have serious respiratory
symptoms causing to acute respiratory distress
syndrome (ARDS) and even death. A key point to
note is that the disease the onset of ARDS in the
early stages and preceding acute lung injury 9.
Currently, there is no specific antiviral drug used
for the treatment of COVID-19. Therefore,
deciding which treatment regimen to apply to
prevent and treat severe COVID-19 cases remains a
major challenge 10. As of now, many studies are
being carried out to develop vaccines that can be
effective against COVID-19 worldwide. Until the
discovery of specific vaccines or therapeutic drugs
targeting SARS-CoV-2, medications approved by
the FDA for other indications are used to treat
COVID-19 patients 11. In this review, we
synthesized the available information regarding
two of the most important antiviral drugs
favipiravir and remdesivir for SARS-CoV-2
therapy.
1. Favipiravir: Favipiravir, also known as T-705,
is a pyrazine analog Fig. 1 and potent inhibitor of
influenza viral RNA polymerase 12. Favipiravir is
converted intracellularly into its ribofuranosyl 5′-
triphosphate (favipiravir-RTP) metabolite, and the
antiviral activity of this drug is decreased in the
existence of the purine nucleotides ATP and GTP,
implying that favipiravir-RTP can be recognized as
a pseudo-purine by the viral RNA-dependent RNA
polymerase (RdRp) 13. For influenza a virus
polymerase it was demonstrated that favipiravir-
RTP was known as an effective substrate for
incorporation in the RNA 14. Incorporation of
favipiravir-RTP in the viral RNA could eventuate
in lethal mutagenesis 15.
The results of several studies have suggested that
one of favipiravir's mechanisms of action for
different viruses is lethal mutagenesis 16, 17.
Otherwise, there are some studies that have
indicated that incorporation of favipiravir-RTP into
the viral RNA strand prevented further, RNA
strand extension is the mechanism of action of this
antiviral drug 18, 19.
Favipiravir was priorily presented to be an effective
antiviral against influenza virus infections; it has
also been shown to be efficient against a large
number of RNA viruses 20.
FIG 1: CHEMICAL STRUCTURE OF FAVIPIRAVIR
An in-vitro study investigating seven potential anti-
SARS-CoV-2 drugs has shown that favipiravir has
exhibited efficacy in Vero E6 cells infected with
SARS-CoV-2 with half-maximal effective
concentration (EC50) of 61.88 μM and half-
cytotoxic concentration (CC50) at over 400 μM,
indicating the high concentration is required for
effective and safe treatment 21. Favipiravir is also
an antiviral agent that has been demonstrated to be
effective for Ebola virus disease. In a retrospective
analysis of patients with Ebola virus disease treated
with favipiravir had a remarkably higher survival
rate compared to receiving supportive therapy
(56.4% vs. 35.3%; P=0.027) 22. Favipiravir is
currently being investigated for the novel
coronavirus disease COVID-19. In an open-label
non-randomized study of 80 patients with COVID-
19 in China, a significant decrease in SARS-CoV-2
viral clearance was observed in patients treated
with favipiravir compared to those treated with
lopinavir/ritonavir 23. In another multicentered
randomized clinical trial in China, favipiravir
treatment has been demonstrated to increase the 7-
day clinical recovery rate (from 55.86% to 71.43%)
and significantly reduce fever and cough relief time
in COVID-19 patients 24. Clinical trials testing
favipiravir for COVID-19 have been conducted in
different countries worldwide Table 1 and 2.
Several studies have indicated that the maximum
plasma concentration of favipiravir occurred at two
hours after oral administration and then reduced
quickly with a short half-life time of 2–5.5 h, and
the fraction of its metabolites excreted in the urine
increases overtime to reach 80–100% after seven
days 25.

Eroglu and Toprak, IJPSR, 2021; Vol. 12(4): 1950-1957. E-ISSN: 0975-8232; P-ISSN: 2320-5148
International Journal of Pharmaceutical Sciences and Research 1952
Favipiravir exhibits dose and time-dependent
pharmacokinetics. It is not metabolized by the
cytochrome P450 system, however, it inhibits one
of its components (CYP2C8). Therefore, it needs to
be used with caution when co-administered with
drugs metabolized by the CYP2C8 system 26. The
most common side effects of favipiravir are
gastrointestinal discomfort, abnormal trans-
aminases, elevated serum uric acid, and psychiatric
symptoms.
TABLE 1: THE ONGOING AND UPCOMING CLINICAL TRIALS WITH FAVIPIRAVIR FOR THE TREATMENT
OF COVID‐19
Study
Clinical
Trials.gov
Identifier
Interventions
Primary Outcome
Study on Safety and Efficacy
of Favipiravir (Favipira) for
COVID-19 Patient in Selected
Hospitals of Bangladesh
NCT04402
203
*Favipiravir 200 mg (Favipira) tablet will be given
orally. Day 1: Tablet Favipiravir 1600 mg twice
daily Days 2−Days 10: Tablet Favipiravir 600 mg
twice daily.
Number of participants
negative by RT-PCR
for the virus at 4-10
days after initiation of
therapy.
Favipiravir Therapy in Adults
With Mild COVID-19 (Avi-
Mild)
NCT04464
408
*Favipiravir: 1800 mg (9 tablets) by mouth twice
daily for one day, followed by 800mg (4 tablets)
twice daily
*Placebo: 9 tablets by mouth twice daily for one
day,
followed by 4 tablets twice daily
PCR negative.
Favipiravir in Hospitalized
COVID-19 Patients (FIC)
NCT04359
615
*Favipiravir: This will be drug only used in the
intervention *Hydroxychloroquine: This drug will
be used in all arms as mandated by their
governmental guidelines
Time to clinical
improvement
Favipiravir vs
Hydroxychloroquine in
COVID -19
NCT04387
760
*Hydroxychloroquine: 400mg BID PO day 1 then
200mg BID PO from day 2-day 10.
*Favipiravir: 1600mg BID PO day 1, 600mg BID
PO day 2 to 10.
Primary outcome
measure will be time to
viral clearance
Oral Favipiravir Compared to
Placebo in Subjects With Mild
COVID-19
NCT04346
628
*Favipiravir: for 10 days, and be evaluated for
health outcomes through day 28.
*Placebo: for 10 days, and be evaluated for health
outcomes through day 28.
Time until the
cessation of oral
shedding of SARS-
CoV-2 virus
A Multicenter, Randomized,
Double-blind, Placebo-
controlled, Phase 3 Study
Evaluating Favipiravir in
Treatment of COVID19
NCT04425
460
*Favipiravir: Day 1: 1800 mg x2; Day 2 up to a
maximum of 14 days 600 mg x 3
*Placebo: Day 1: 1800 mg x2; Day 2 up to a
maximum of 14 days 600 mg x 3
Time from
randomization to
clinical recovery.
Efficacy and Safety of
Favipiravir in Management of
COVID-19
NCT04349
241
*Favipiravir in a regimen of 3200 mg (1600 mg 12
hourly) loading dose on day-1 followed by 1200
mg maintenance dose (600 mg 12 hourly daily) on
day-2 to day-10
1. Viral clearance
2. Clinical
improvement
Early Intervention in COVID-
19: Favipiravir Verses
Standard Care (PIONEER)
NCT04373
733
*Favipiravir: Day 1 1800mg twice per day, Days 2-
10 800mg twice per day
Time to improvement
by two points on a
seven-category ordinal
scale
Efficacy of Faviprevir in
COVID-19 Treatment
NCT04351
295
*Favipiravir
*Placebos
Number of patients
with viral cure
*A registry and results database of privately and publicly supported clinical studies of human participants conducted around the
world. Available online: www.ClinicalTrials.gov
In addition, other existing safety concerns, such as
the potential for QTc prolongation, are still
unresolved 27. Furthermore, there is proof that
favipiravir has teratogenic potential. When the
doses equivalent to the recommended human
regimens were tested in animal models, retarded
development of embryonic death was observed in
four different animal species in the first trimester
28. There is no information about the use of
favipiravir during breastfeeding or its excretion into

Eroglu and Toprak, IJPSR, 2021; Vol. 12(4): 1950-1957. E-ISSN: 0975-8232; P-ISSN: 2320-5148
International Journal of Pharmaceutical Sciences and Research 1953
breast milk. However, since favipiravir is a small
molecule that is approximately 60% protein-bound
in plasma, it may be expected to appear in breast
milk and be absorbed by the infant slightly.
Therefore, the breastfed infant should be monitored
in terms of some parameters such as gastro-
intestinal symptoms, liver enzyme abnormalities,
and serum uric acid elevations 29. Favipiravir seems
to be safe and tolerable in short-term use, but more
evidence is needed to evaluate the longer-term
effects of COVID-19 treatment. The clinical
application of favipiravir is being researched for
clear information about its effectiveness and safety.
2. Remdesivir: Remdesivir (GS-5734) is a
monophosphoramidate prodrug, a C-adenosine
nucleoside analog Fig. 2 and a new antiviral drug
with broad antiviral action against zoonotic and
human pathogens from multiple virus families. It
was developed by Gilead Sciences as a treatment
for Ebola virus disease and Marburg virus
infections 30. Remdesivir terminates viral RNA
synthesis by inhibiting viral RNA-dependent RNA
polymerase (RdRp) 31. The active form, remdesivir
triphosphate, compete for the inclusion of the
native adenosine triphosphate chain, resulting in
chain termination 32. Remdesivir is a broad-
spectrum antiviral drug with effects on ribonucleic
acid (RNA) viruses, including Coronaviridae (such
as SARS-CoV, MERS-CoV, and bat coronavirus
strains), Filoviridae (such as EBOV), and
Paramyxoviridae (Nipah virus, Hendra virus) 33.
Laboratory tests show that remdesivir is effective
against a wide variety of viruses such as SARS-
CoV and MERS-CoV.
FIG. 2: CHEMICAL STRUCTURE OF REMDESIVIR
In previous studies, it has been tested on RNA
viruses such as MERS coronavirus and SARS
coronavirus but has not been fully approved as a
treatment drug. Remdesivir was originally
developed for Hepatitis C, then it was tried in
Ebola and Marburg virus, but its effectiveness was
not proven in all these infections. Although the
drug has proven to be safe, its effect against
filoviruses such as the Ebola virus has not been
observed 33. After the COVID-19 pandemic,
treatment protocols have begun to be tried on
patients, and finally. Remdesivir has been approved
for emergency use in the USA and for the treatment
of patients with severe symptoms in Japan 33. A
number of factors have led to increased public and
medical interest in remdesivir for SARS-CoV-2
treatment recently.
First, its in-vitro activity against SARS-CoV-2 was
confirmed. Researchers studied the effect of seven
drugs: ribavirin, penciclovir, nitazoxanide,
nafamostat, chloroquine, favipiravir, and rem-
desivir against SARS-CoV-2 in non-human Vero
E6 cells. The EC50 was the lowest for remdesivir
(0.77 µM), followed by chloroquine (1.13 µM).
The simulated molecular insertion experiment also
predicted that remdesivir could bind high-affinity
SARS-CoV-2 RdRp 21. The first clinical efficacy
data for remdesivir in COVID-19 focused on case
reports of patients. All cases described received
200 mg of remdesivir intravenously on day 1
followed by 100 mg for up to 9 days 33. The first
patient, a 35-year-old man with a limited past
medical history and recent travel to Wuhan,
diagnosed with COVID-19 in the United States,
was treated with remdesivir.
Remdesivir was initiated on day 7 due to increased
oxygen requirements and ongoing pyrexia, and was
generally asymptomatic in the following days 34.
The largest report included 61 patients from centers
in Europe, North America, and Japan. All patients
were hospitalized with COVID-19. After 8 patients
were excluded for a number of reasons, 53 patients
were received remdesivir at a median of 12 days
following symptom onset, and clinical improve-
ment was detected in 36 of these 53 patients (68%)
35. In the first randomized, placebo-controlled,
double-blind study with remdesivir for COVID-19,
Wang and colleagues matched patients receiving
remdesivir (n=158) and placebo (n=78) in
hospitalized patients with severe COVID-19.
Remdesivir was given a dose of 200 mg on day 1,

Eroglu and Toprak, IJPSR, 2021; Vol. 12(4): 1950-1957. E-ISSN: 0975-8232; P-ISSN: 2320-5148
International Journal of Pharmaceutical Sciences and Research 1954
followed by a dose of 100 mg on days 2-10. In
most of the patients with medical comorbidities, the
basic characteristics were detected to be balanced,
and a higher respiratory rate was found after 10
days 36. In another open observational study of
patients having received a 10-day remdesivir
therapy, these patients not requiring mechanical
ventilation, the trial did not demonstrate a
significant difference between a 5-day course and a
10-day course of remdesivir 37. Clinical trials
testing remdesivir for COVID-19 have been carried
out in different countries of the world Table 3 and 4.
TABLE 2: THE ONGOING AND UPCOMING CLINICAL TRIALS WITH FAVIPIRAVIR FOR THE TREATMENT
OF COVID‐19 (CONTINUE)
Study
Clinical
Trials.
Gov.
Identifier
Interventions
Primary Outcome
Efficacy and Safety of
Hydroxychloroquine and
Favipiravir in the Treatment
of Mild to Moderate
COVID-19
NCT0441
1433
*Favipiravir (3200 mg+1200 mg)
*Favipiravir (3600 mg+1600 mg)
*Favipiravir combined with Hydroxychloroquine
*Favipiravir combined with Azithromycin
*Hydroxychloroquine
*Hydroxychloroquine combined with Azithromycin
1. Time to recovery
(discharge)
2. Decrease in viral load
Favipiravir and
Hydroxychloroquine
Combination Therapy
(FACCT)
NCT0439
2973
*Favipiravir: Administer 1800 mg (9 tablets) by
mouth twice daily for one day, followed by 800mg (4
tablets) twice daily (total days of therapy is 10 days
or till hospital discharge)
*Hydroxychloroquine (400mg) twice daily on day 1;
for days 2-5 (200mg) twice daily.
Clinical Improvement..
Corona Virus Disease 2019
Patients Whose Nucleic
Acids Changed From
Negative to Positive
NCT0433
3589
*Favipiravir: On the 1st day, 1600mg each time,
twice a day; from the 2nd to the 7th day, 600mg each
time, twice a day. Oral administration, the maximum
number of days taken is not more than 14 days.
Viral nucleic acid test
negative conversion rate
Control of COVID-19
Outbreaks in Long Term
Care
NCT0444
8119
*Favipiravir for prophylaxis is 1600 mg (8 x 200 mg
tablets) orally twice daily on day 1 followed by 800
mg (4 x 200 mg tablets) orally twice daily on days 2-
25 and for treatment is 2000 mg orally twice daily on
day 1, the 1000 mg orally twice daily for 13
additional days.
*Favipiravir Placebo
Control of Outbreak
Treatments to Decrease the
Risk of Hospitalization or
Death in Elderly Outpatients
With Symptomatic SARS-
CoV-2 Infection (COVID-
19) (COVERAGE)
NCT0435
6495
*Favipiravir: 12 tablets twice a day the first day (day
0) then 6 tablets twice a day from day 1 to day 9
*Imatinib: 1 tablet daily from the first day (day 0) to
day 9
*Telmisartan: 1 tablet daily from the first day (day 0)
to day 9
*Dietary Supplement: Vitamins 2 tablets daily from
the first day (day 0) to day 9
1. Proportion of
participants with an
occurrence of
hospitalization
2. Death
Bioequivalence Study of
Favipiravir 200 mg Film
Tablet (ATABAY, Turkey)
Under Fasting Conditions
(Favipiravir)
NCT0440
6194
*Favipiravir 200 mg (FAVICOVIR)
*Favipiravir 200 mg (Avigan)
1. Primary PK End
Points. AUC0-tlast of
favipiravir obtained by
plasma concentration
2. Primary PK End
Points. Cmax of favipiravir
obtained by plasma
concentration
*A registry and results database of privately and publicly supported clinical studies of human participants conducted around the
world. Available online: www.ClinicalTrials.gov
Remdesivir is a substrate of several cytochrome
P450 enzymes in-vitro, but clinical implications are
still unclear since the pro-drug is rapidly
metabolized by plasma hydrolases 38. Remdesivir
has linear pharmacokinetics and an extended
intracellular half-life (>35 h for active parent
triphosphate). Remdesivir triphosphate accumulates
in peripheral blood mononuclear cells and therefore

Eroglu and Toprak, IJPSR, 2021; Vol. 12(4): 1950-1957. E-ISSN: 0975-8232; P-ISSN: 2320-5148
International Journal of Pharmaceutical Sciences and Research 1955
recommending a loading dose may accelerate the
stable success situation 39. Detailed information on
remdesivir metabolism and elimination is not
available. In remdesivir studies, the most common
side effects were reported as respiratory failure,
organ failure, low albumin, low potassium,
reduction in red blood cells and platelet counts
leading to clotting and yellowing of the skin.
TABLE 3: THE ONGOING AND UPCOMING CLINICAL TRIALS WITH REMDESIVIR FOR THE TREATMENT
OF COVID‐19
Study
Clinical
Trials.
Gov.
Identifie
r
Interventions
Primary Outcome
Multicenter, Retrospective Study of
the Effects of Remdesivir in the
Treatment of Severe Covid-
19 Infections (REMDECO-19)
NCT043
65725
*Retrospective cohort trial to
assess the efficacy of
remdesivir in hospitalized
adult patients (158 to
remdesivir and 79 to plasebo)
diagnosed with COVID-19.
not provide significant clinical or
antiviral effects in seriously ill patients
with COVID-19.
A Trial of Remdesivir in Adults With
Severe COVID-19
NCT042
57656
*Remdesivir, 200 mg loading
dose on day 1, is given,
followed by 100 mg iv once-
daily maintenance doses for 9
days.
Time to clinical improvement
Study of Merimepodib in
Combination With Remdesivir in
Adult Patients With
Advanced COVID-19
NCT044
10354
Merimepodib 400 mg (total
daily dose of 1200 mg) for 10
days
Remdesivir 200 mg loading
dose on Day 0 followed by
100 mg daily dose for 4 days.
1.Number of subjects not hospitalized
or, if hospitalized, free of respiratory
failure
2. Adverse Events
Study to Evaluate the Safety,
Tolerability, Pharmacokinetics, and
Efficacy of Remdesivir (GS-5734™)
in Participants From Birth to < 18
Years of Age With Coronavirus
Disease 2019 (COVID-19)
(CARAVAN)
NCT044
31453
To evaluate the safety,
tolerability, and
pharmacokinetics (PK) of
remdesivir (RDV) in
participants with laboratory-
confirmed coronavirus disease
2019 (COVID-19) aged 0
days to < 18 years.
1. Proportion of Participants
Experiencing any Treatment-Emergent
Adverse Events
2. Proportion of Participants
Experiencing any Treatment-Emergent
Graded Laboratory Abnormalities
3.Plasma Concentrations of Remdesivir
(RDV) and Metabolites
Study in Participants With Early
Stage Coronavirus Disease 2019
(COVID-19) to Evaluate the Safety,
Efficacy, and Pharmacokinetics of
Remdesivir Administered by
Inhalation
NCT045
39262
Drug: Remdesivir (RDV)
Drug: Placebo
Time-weighted Average Change From
Baseline in Severe Acute Respiratory
Syndrome Coronavirus 2 (SARS-CoV-
2) Viral Load Through Day 7
*A registry and results database of privately and publicly supported clinical studies of human participants conducted around the
world. Available online: www.ClinicalTrials.gov
Other side effects have been defined as
gastrointestinal disorders, increased liver enzymes,
and reactions in the treated vessel. During the
drug's intravenous administration, patients may
experience low blood pressure, nausea, vomiting,
sweating, and tremor 33.
Because remdesivir is slightly absorbed orally,
infants are unlikely to absorb clinically significant
amounts of the drug from the milk. Given the
limited information on infants, it does not appear
that mothers taking remdesivir should avoid
breastfeeding, but until more data are available,
remdesivir should be used with careful infant
monitoring during breastfeeding 40.
Although the use of remdesivir in COVID-19
seems safe, more studies are needed regarding its
efficacy and safety.

Eroglu and Toprak, IJPSR, 2021; Vol. 12(4): 1950-1957. E-ISSN: 0975-8232; P-ISSN: 2320-5148
International Journal of Pharmaceutical Sciences and Research 1956
TABLE 4: THE ONGOING AND UPCOMING CLINICAL TRIALS WITH REMDESIVIR FOR THE TREATMENT
OF COVID‐19 (CONTINUE)
Study
Clinical
Trials. Gov.
identifier
Interventions
Primary Outcome
A Study to Evaluate the Efficacy and
Safety of Remdesivir Plus Tocilizumab
Compared With Remdesivir Plus Placebo
in Hospitalized Participants With
Severe COVID-19 Pneumonia
(REMDACTA)
NCT0440926
2
Drug: Remdesivir Drug:
TocilizumabDrug: Placebo
Clinical Status as
Assessed by the
Investigator Using a 7-
Category Ordinal Scale
of Clinical Status on
Day 28
The Efficacy of Different Anti-viral Drugs
in COVID 19 Infected Patients
NCT0432161
6
Remdesivir for 10 days versus
hydroxychloroquine for 10 days versus
placebo
In-hospital mortality
Trial of Treatments for COVID-19 in
Hospitalized Adults (DisCoVeRy)
NCT0431594
8
Treatment arms include remdesivir for 10
days, lopinavir/ ritonavirc for 14 days,
lopinavir/ritonavir for 14 days plus
interferon beta-1a 44 mcg subcutaneously
on days 1, 3, and 6, hydroxychloroquined
for 10 days, or standard care
Percentage of subjects
reporting each severity
rating on a 7-point
ordinal scale
Remdesivir in COVID-19 Lahore General
Hospital
NCT0456023
1
200 mg I/v Remdesivir will be given to
moderate disease patients of COVID-19.
It will be loading dose then 100 mg I/V
dose will be given for 5 days.
Clinical response after
administration
Remdesivir vs Chloroquine in Covid 19
NCT0434541
9
Drug: Chloroquine or
hydroxychloroquine
Drug: Remdesivir
Number of patients with
improvement or
mortality
*A registry and results database of privately and publicly supported clinical studies of human participants conducted around the
world. Available online: www.ClinicalTrials.gov
CONCLUSION: To summarize, favipiravir and
remdesivir have been suggested as a promising
alternative for COVID-19 therapy based on the
findings of in vitro tests, case reports, and clinical
trials, but their safety and effects have not yet been
fully understood. While vaccine and drug research
is still ongoing, various studies on the relationship
between antiviral drugs and coronavirus have been
conducted at the same time. The use of favipiravir
and remdesivir for COVID-19 treatment has not
been clarified yet, and more detailed studies are
needed on these drugs. The ongoing studies will
provide more high-quality evidence on the benefit
and harmful effects of favipiravir and remdesivir.
ACKNOWLEDGEMENT: Nil
CONFLICTS OF INTEREST: The author has no
conflicts of interest in the present review.
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How to cite this article:
Eroglu E and Toprak C: Overview of favipiravir and remdesivir treatment for Covid-19. Int J Pharm Sci & Res 2021; 12(4): 1950-57. doi:
10.13040/IJPSR.0975-8232.12(4).1950-57.