Favipiravir versus other antiviral or standard of care for COVID-19 treatment: a rapid systematic review and meta-analysis

Unveiling therapeutic dynamics: An in-depth comparative analysis of neutralizing monoclonal antibodies and favipiravir in alleviating COVID-19 outpatients impacts among middle-aged and special populations (MA-FAST)

BACKGROUND

Neutralizing monoclonal antibodies (NMabs) are recognized for their efficacy against non-severe COVID-19. However, spike protein mutations may confer resistance. This study evaluates the effectiveness of favipiravir (FPV) versus NMabs in preventing severe COVID-19 in special populations.

METHODS

A retrospective cohort was conducted on middle-aged, elderly, diabetic, or obese patients with COVID-19 treated with either FPV or NMabs. Propensity score matching (PSM) was used for analysis.

RESULTS

The study included 1410 patients, resulting in four cohorts: middle-aged (36), elderly (48), diabetic (46), and obese (28) post-PSM. No significant differences were noted in 28-day emergency department (ED) visits across all groups between NMabs and FPV treatments, despite lower immunity in the FPV group. However, the diabetic group treated with FPV had higher 28-day hospitalization and oxygen supplemental, with no differences in the other groups. Intensive care unit (ICU) admissions, invasive mechanical ventilation, and mortality rates were similar between the two treatments.

CONCLUSIONS

Early dose-adjusted FPV showed no difference from NMabs in preventing ED visits, ICU admissions, ventilator needs, or mortality among patients with major comorbidities. Diabetic patients on FPV experienced higher hospitalizations and oxygen needs, with no observed differences in other groups. FPV may be a viable alternative, especially in settings with limited resources.

Favipiravir does not improve viral clearance in mild to moderate COVID-19 - A systematic review and meta-analysis of randomized controlled trials

Purpose

Favipiravir has been used in the therapy of COVID-19, including patients with mild to moderate symptoms in certain countries. The aim of our systematic review and meta-analysis was to investigate its efficacy and safety in mild-to-moderate COVID-19 infections.

Methods

The PubMed, Embase, Web of Science, and Cochrane databases were systematically reviewed for articles reporting the results of randomized controlled trials published until January 6, 2023, resulting in the identification of 20 eligible studies.

Results

There were no significant differences in viral clearance time (HR = 1.20, p = 0.09) compared to those without favipiravir therapy. However, in the subgroup analyses, favipiravir treatment significantly increased viral clearance by 59 % (HR = 1.59, p < 0.01) and 42 % (HR = 1.42, p < 0.01], I2 = 20 %) compared to the comparator group in patients with moderate severity of COVID-19 and in the inpatient care setting, respectively. Favipiravir had no beneficial effects in the case of patients with mild symptoms and treated in ambulatory care.

Conclusions

The use of favipiravir is questionable in the treatment of outpatients with COVID-19 with mild symptoms. Moderate beneficial effects in the case of patients with moderate symptoms and inpatients should be treated with care due to the limitations of the analysed trials.

A randomized trial to assess the acceleration of viral clearance by the combination Favipiravir/Ivermectin/Niclosamide in mild-to-moderate COVID-19 adult patients (FINCOV)

BACKGROUND

The efficacy of the viral clearance and clinical outcomes of favipiravir (FPV) in outpatients being treated for coronavirus disease 2019 (COVID-19) is unclear. Ivermectin (IVM), niclosamide (NCL), and FPV demonstrated synergistic effects in vitro for exceed 78% inhibiting severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) replication.

METHODS

A phase 2, open-label, 1:1, randomized, controlled trial was conducted on Thai patients with mild-to-moderate COVID-19 who received either combination FPV/IVM/NCL therapy or FPV alone to assess the rate of viral clearance among individuals with mild-to-moderate COVID-19.

RESULTS

Sixty non-high-risk comorbid patients with mild-to-moderate COVID-19 were randomized; 30 received FPV/IVM/NCL, and 30 received FPV alone. Mixed-effects multiple linear regression analysis of the cycle threshold value from SARS-CoV-2 PCR demonstrated no statistically significant differences in viral clearance rates between the combined FPV/IVM/NCL therapy group and the FPV-alone group. World Health Organization Clinical Progression scores and symptomatic improvement did not differ between arms on days 3, 6, and 10, and no adverse events were reported. No patients required hospitalization, intensive care unit admission, or supplemental oxygen or died within 28 days. C-reactive protein on day 3 was lower in the FPV/IVM/NCL group.

CONCLUSION

Viral clearance rates did not differ significantly between the FPV/IVM/NCL combination therapy and FPV-alone groups of individuals with mild-to-moderate COVID-19, although the combined regimen demonstrated a synergistic effect in vitro. No discernible clinical benefit was observed. Further research is required to explore the potential benefits of FVP beyond its antiviral effects.

TRIAL REGISTRATION

TCTR20230403007, Registered 3 April 2023 - Retrospectively registered,https://trialsearch.who.int/Trial2.aspx?TrialID=TCTR20230403007.

Favipiravir, remdesivir, and lopinavir: metabolites, degradation products and their analytical methods

Severe acute respiratory syndrome 2 (SARS-CoV-2) caused the emergence of the COVID-19 pandemic all over the world. Several studies have suggested that antiviral drugs such as favipiravir (FAV), remdesivir (RDV), and lopinavir (LPV) may potentially prevent the spread of the virus in the host cells and person-to-person transmission. Simultaneously with the widespread use of these drugs, their stability and action mechanism studies have also attracted the attention of many researchers. This review focuses on the action mechanism, metabolites and degradation products of these antiviral drugs (FAV, RDV and LPV) and demonstrates various methods for their quantification and discrimination in the different biological samples. Herein, the instrumental methods for analysis of the main form of drugs or their metabolite and degradation products are classified into two types: optical and chromatography methods which the last one in combination with various detectors provides a powerful method for routine and stability analyses. Some representative studies are reported in this review and the details of them are carefully explained. It is hoped that this review will be a good guideline study and provide a better understanding of these drugs from the aspects investigated in this study.

Efficacy of combined COVID-19 convalescent plasma with oral RNA-dependent RNA polymerase inhibitor treatment versus neutralizing monoclonal antibody therapy in COVID-19 outpatients: a multi-center, non-inferiority, open-label randomized controlled trial (PlasMab)

IMPORTANCE

This pivotal study reveals that high neutralizing titer COVID-19 convalescent plasma therapy (CPT) combined with favipiravir (FPV) is non-inferior to sotrovimab in preventing hospitalization and severe outcomes in outpatients with mild-to-moderate COVID-19 and high-risk comorbidities. It underscores the potential of CPT-FPV as a viable alternative to neutralizing monoclonal antibodies like sotrovimab, especially amid emerging variants with spike protein mutations. The study's unique approach, comparing a monoclonal antibody with CPT, demonstrates the efficacy of early intervention using high neutralizing antibody titer CPT, even in populations with a significant proportion of elderly patients. These findings are crucial, considering the alternative treatment challenges, especially in resource-limited countries, posed by the rapidly mutating SARS-CoV-2 virus and the need for adaptable therapeutic strategies.

The real-world effectiveness of fluvoxamine therapy in mild to moderate COVID-19 patients; A historical cohort study (Fluvoxa Trial)

BACKGROUND

Fluvoxamine (FVX) has been proposed as a potential treatment for severe COVID-19 by the σ-1 receptor agonist, which can reduce cytokine production. However, the efficacy of FVX remains controversial.

METHODS

A historical retrospective cohort study was conducted in mild to moderate COVID-19 patients, 2:1 ratio of standard of care (SOC) and FVX treatments to assess the effectiveness of FVX in preventing deterioration by the fifth day of treatment.

RESULTS

Of 752 eligible patients, 234 received FVX while 518 received SOC, and there was no significant difference in the effectiveness of FVX and SOC in preventing clinical deterioration. On the fifth day after treatment, 86.1 % of patients in the FVX-treated group did not experience clinical deterioration compared to 78.7 % in the SOC group. Notably, the FVX group had higher rates of pneumonia development and hospitalization, requiring more oxygen supplementation while showing less reduction in viral shedding than the SOC group. However, no difference in mechanical ventilation use, ICU admission, and survival was observed.

CONCLUSION

Fluvoxamine treatment is failed to demonstrate effectiveness in preventing deterioration in mild to moderate COVID-19 and may lead to a higher incidence of pneumonia, hospitalization, and oxygen supplementation, necessitating careful consideration before prescribing the drug for COVID-19.

Efficacy of Andrographis paniculata extract treatment in mild to moderate COVID-19 patients being treated with favipiravir: A double-blind, randomized, placebo-controlled study (APFaVi trial)

BACKGROUND

While favipiravir had been the standard anti-SARS-CoV-3 drug for COVID-19 treatment in Thailand, the efficacy of favipiravir treatment is controversial. Andrographis paniculata extract (APE) inhibits viral entry, exhibits immunomodulatory effects, and proposes to have the potential for early-stage COVID-19 treatment.

METHODS

A randomized, double-blind, placebo-controlled trial was performed in Thailand during June - September 2021. Non-severe COVID-19 patients were randomized 1:1 to groups receiving 180 mg/day of APE plus favipiravir (APE-FPV group) or placebo plus favipiravir (placebo-FPV group). Efficacy in preventing disease progression to severe COVID-19 was assessed on day 4, using World Health Organization Clinical Progression Scale (WHOCPS) score and visual analog scale (VAS) for acute respiratory tract infection symptoms.

RESULTS

Of 146 patients, there were 73 patients in each group. Non-deterioration of WHOCPS scores on day 4 was 98.63% versus 97.26% of patients in the APE-FPV and placebo-FPV groups (p = 1.000). No difference in supplemental oxygen, hospitalization, and death was shown in both groups. The oxygen supplemental was 4.11% in the placebo-FPV group. The interleukin (IL)-1β was significantly lower in the APE than in the placebo-FPV group throughout the study. We found no difference in virologic outcomes between groups and no substantial adverse events.

CONCLUSIONS

APE treatment did not demonstrate additional clinical and virological benefits in patients with mild to moderate COVID-19 being treated with favipiravir. Early reduction of IL-1β with APE may be advantageous in preventing cytokine storms in severe COVID-19 and requires further study.

Favipiravir treatment in non-severe COVID-19: promising results from multicenter propensity score-matched study (FAVICOV)

This study aimed to evaluate the efficacy of favipiravir (FPV) in preventing the development of severe COVID-19 in patients with mild-to-moderate symptoms. The study evaluated 1037 COVID-19 patients treated with FPV or standard treatment between April and September 2021, analyzed by propensity score matching. 149 patients were included in each arm after propensity score matching. The clinical outcomes showed no deterioration of the WHO clinical progression scale in the FPV group compared to the standard treatment group on day 5 (83.2% vs. 69.1%, p < 0.001). The WHO clinical progression scale also showed improvements on day 14 in the FPV group compared to the standard treatment group (66.4% vs. 46.3%, p < 0.001). The rates of oxygen supplementation and hospitalization were significantly lower in the FPV group compared to the standard treatment group (0% vs. 12.1% and 0.7% vs. 17.4%, respectively, p < 0.001 for both). There were no differences in adverse events between the two groups. The study highlights the effectiveness of FPV in preventing severe COVID-19 and hospitalization in patients with mild-to-moderate symptoms. The findings emphasize the importance of personalized treatment plans for COVID-19 patients, starting FPV treatment early, and adjusting dosages based on ethnicity and body weight.

Efficacy of combination therapy of fluvoxamine and favipiravir vs favipiravir monotherapy to prevent severe COVID-19 among mild to moderate COVID-19 patients: Open-label randomized controlled trial (EFFaCo study)

OBJECTIVES

Fluvoxamine (FVX) is an antidepressant proposed to its immunomodulatory effects in preventing deterioration in mild and moderate COVID-19.

METHODS

An open-label, 1:1 randomized controlled trial was assigned either combination therapy 50 mg twice daily of FVX for 10 days and favipiravir (FPV) or FPV alone to assess the efficacy in preventing disease progression in mild to moderate COVID-19 on the 5th day.

RESULTS

In total, 134 patients with mild COVID-19 received FPV and 132 received FVX/FPV, 31 patients with moderate COVID-19 received FPV/dexamethasone (FPV/Dex), and 30 received FVX/FPV/Dex. The intention-to-treat (ITT) analysis showed no difference of no clinical deterioration on the 5th day in both mild COVID-19 (100% in FPV vs 97% in FVX/FPV) and moderate COVID-19 (83.9% in FPV/Dex vs 86.7% in FVX/FPV/Dex). However, there was a low rate of oxygen supplemental, hospitalization, or intensive care in both groups and zero death in all groups. No significant difference in oxygen supplemental, hospitalization, radiological, virological, or biochemical outcomes, and the immunomodulatory effect was observed between the group.

CONCLUSION

The combined fluvoxamine treatment did not add benefit in preventing deterioration in patients with mild to moderate COVID-19 without the immunomodulatory effect observed, although it demonstrated low hospitalization rates, oxygen supplemental, intensive care needed, and zero mortality.

TRIAL REGISTRATION

Thai clinical trials registry (TCTR) no. 20210615002.

Impact of common comorbidities on antimicrobial consumption and mortality amongst critically ill COVID-19 patients: A retrospective two center study in Saudi Arabia

Objectives

To determine the association between common comorbidities, ICU mortality and antimicrobial consumption among critically ill COVID 19 patients in Saudi Arabia.

Methods

A retrospective observational study of patients admitted to the ICU from March 1st, 2020, through August 31st, 2021. We excluded patients who stayed <24 h in the ICU and with no confirmed COVID-19 PCR testing.

Results

Of the 976 screened ICU patients, 848 were included. While there was no difference in mortality between patients with and without comorbidities, those with at least one comorbidity had a higher severity of illness (p = 0.013). Compared to survivors, non-survivors were more likely to require mechanical ventilation and vasopressor support (P < 0.001). Almost all patients received at least one antimicrobial therapy. Predictors independently associated with ICU mortality were: older age (adjusted odds ratio [AOR], 1.03; 95% confidence interval [CI], 1.01-1.04), vancomycin use (AOR, 2.69; 95% [CI], 1.65-4.37), linezolid use (AOR, 2.65; 95% [CI], 1.65-4.04), sepsis or septic shock (AOR, 6.39; 95% [CI], 3.68-11.08), Acute Kidney Injury (AKI) (AOR, 2.51; 95% [CI], 1.61-3.92) and Acute Respiratory Distress Syndrome (ARDS) (AOR, 2.03; 95% [CI], 1.61-3.92).

Conclusion

Older age, vancomycin and linezolid use, sepsis/septic shock, AKI, and ARDS were negative prognostic factors in critically ill COVID-19 patients. More studies are needed to evaluate the outcomes of survived critically ill patients in relation to their vaccination status.

The Real-World Clinical Outcomes of Favipiravir Treatment with Telemedicine Monitoring in Preventing Disease Progression in Mild to Moderate COVID-19 Patients; A Retrospective Cohort Study

Background: Favipiravir has complex pharmacokinetics, and varied efficacy has been reported in treating COVID-19. Telehealth and telemonitoring are disruptive challenges used for COVID-19 care during pandemics. Objective: This study aimed to assess the outcome of favipiravir treatment to prevent clinical deterioration in mild to moderate COVID-19 cases with adjunctive telemonitoring during the COVID-19 surge. Methods: This was a retrospective observational study of PCR-confirmed mild to moderate COVID-19 cases subjected to home isolation. Chest computed tomography (CT) was performed in all cases, and favipiravir was administrated. Results: This study involved 88 PCR-confirmed COVID-19 cases. In addition, 42/42 (100%) cases were Alpha variants. COVID-19 pneumonia was found in 71.5% of the cases, according to chest X-rays and chest CT on the first visit. Favipiravir started 4 days after symptoms, which was part of the standard of care. The 12.5% of the patients required supplemental oxygen and intensive care unit admission rate was 1.1%; 1.1% required mechanical ventilation, and the rate of all-cause mortality was 1.1%, with a value of 0% of severe COVID-19 deaths. All mild illness cases showed no clinical deterioration or requirement for supplemental oxygen. No significant deterioration in either obesity or diabetes mellitus was observed. Conclusions: Favipiravir treatment for mild to moderate COVID-19 cases in outpatient settings, coupled with telemonitoring, was both safe and effective in preventing clinical deterioration, including the need for oxygen supplementation. This approach proved valuable during surges of COVID-19 cases.

Qualitative and semi-quantitative ultrasound assessment in delta and Omicron Covid-19 patients: data from high volume reference center

OBJECTIVE

to evaluate the efficacy of US, both qualitatively and semi-quantitatively, in the selection of treatment for the Covid-19 patient, using patient triage as the gold standard.

METHODS

Patients admitted to the Covid-19 clinic to be treated with monoclonal antibodies (mAb) or retroviral treatment and undergoing lung ultrasound (US) were selected from the radiological data set between December 2021 and May 2022 according to the following inclusion criteria: patients with proven Omicron variant and Delta Covid-19 infection; patients with known Covid-19 vaccination with at least two doses. Lung US (LUS) was performed by experienced radiologists. The presence, location, and distribution of abnormalities, such as B-lines, thickening or ruptures of the pleural line, consolidations, and air bronchograms, were evaluated. The anomalous findings in each scan were classified according to the LUS scoring system. Nonparametric statistical tests were performed.

RESULTS

The LUS score median value in the patients with Omicron variant was 1.5 (1-20) while the LUS score median value in the patients with Delta variant was 7 (3-24). A difference statistically significant was observed for LUS score values among the patients with Delta variant between the two US examinations (p value = 0.045 at Kruskal Wallis test). There was a difference in median LUS score values between hospitalized and non-hospitalized patients for both the Omicron and Delta groups (p value = 0.02 on the Kruskal Wallis test). For Delta patients groups the sensitivity, specificity, positive and negative predictive values, considering a value of 14 for LUS score for the hospitalization, were of 85.29%, 44.44%, 85.29% and 76.74% respectively.

CONCLUSIONS

LUS is an interesting diagnostic tool in the context of Covid-19, it could allow to identify the typical pattern of diffuse interstitial pulmonary syndrome and could guide the correct management of patients.

Convex optimization for maximizing the degradation efficiency of chloroquine in a flow-by electrochemical reactor

The degradation efficiency of chloroquine phosphate (CQ), an anti-COVID-19 drug, was investigated in a flow-by electrochemical reactor (FBER) provided with two boron-doped diamond (BDD) electrodes (as cathode and anode) under batch recirculation mode. A central composite rotatable design (CCRD) was run down to model and assess the influence of initial pH in an interval of 3.71 to 11.28, the current density in an interval of 34.32 to 185.68 mA cm-2, and liquid volumetric flow rate in an interval of 0.58 to 1.42 L min-1, and conduct the convex optimization to obtain the maximum degradation efficiency. Experimental results were modeled through a second-order polynomial equation having a determination coefficient (R2) of 0.9705 with a variance coefficient of 1.1%. Optimal operating conditions found (initial pH of 5.38, current density (j) of 34.4 mA cm-2, and liquid flow rate (Q) of 1.42 L min-1) led to a global maximum degradation efficiency, COD removal efficiency, and mineralization efficiency of 89.3, 51.6 and 53.1%, respectively, with an energy consumption of 0.041 kWh L-1 within 9 h of treatment. Additionally, a pseudo-zero-order kinetic model was demonstrated to fit the experimental data and the calculated pseudo-zero-order kinetic constant (kapp) was 13.14 mg L-1 h-1 (2.54 × 10-5 mol dm-3 h-1). Furthermore, the total operating cost was of 0.47 US$ L-1. Finally, this research could be helpful for the treatment of wastewater containing an anti-COVID-19 drug such as CQ.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10008-023-05452-7.

Cost-effectiveness of Favipiravir in moderately to severely ill COVID-19 patients in the real-world setting of Saudi Arabian pandemic referral hospitals

Purpose

We aimed to evaluate the cost effectiveness of Favipiravir treatment versus SC in moderately to severely ill COVID-19 patients from the Saudi healthcare payer perspective.

Methods

We used the patient-level simulation method to simulate a cohort of 415 patients with moderate to severe COVID-19 disease who were admitted to two Saudi COVID-19 referral hospitals: 220 patients on Favipiravir and 195 patients on SC. We estimated the incremental cost-effectiveness ratio (ICER) of Favipiravir versus SC in terms of the probability to be discharged alive from hospital and the mean time in days to discharge one patient alive. The model was performed twice: first, using unweighted, and second, using weighted clinical and economic data. Weighting using the inverse weight probability method was performed to achieve balance in baseline characteristics.

Results

In the unweighted model, base case (probabilistic) ICER estimates favored Favipiravir at savings of Saudi Riyal (SAR)1,611,511 (SAR1,998,948) per 1% increase in the probability of being discharged alive. As to mean time to discharging one patient alive, ICERs favored Favipiravir at savings of SAR11,498 (SAR11,125). Similar results were observed in the weighted model with savings using Favipiravir of SAR1,514,893 (SAR2,453,551) per 1% increase in the probability of being discharged alive, and savings of SAR11,989 (SAR11,277) for each day a patient is discharged alive.

Conclusion

From the payer perspective, the addition of Favipiravir in moderately to severely ill COVID-19 patients was cost-savings over SC. Favipiravir was associated with a higher probability of discharging patients alive and lower daily spending on hospitalization than SC.

Comparison of Different Antiviral Regimens in the Treatment of Patients with Severe COVID-19: A Retrospective Cohort

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes respiratory disorders, with disease severity ranging from asymptomatic to critical manifestations. The current retrospective study compared the efficacies of different antiviral regimens used in patients suffering from severe COVID-19 disease from 19 January 2020 to December 2021 in a single center in Saudi Arabia. In total, 188 patients were enrolled in the current study, including 158 patients treated with different antiviral regimens, and 30 who did not receive any antiviral treatment. Different antiviral regimens, including favipiravir, remdesivir, oseltamivir, favipiravir/remdesivir, and favipiravir/oseltamivir were adopted. The effects of using different antivirals and antibiotics on the survival rate were evaluated, as well as the presence of comorbidities. Among all severely affected patients, 39/188 (20.7%) survived. Both age and comorbidities, including diabetes and hypertension, were significantly correlated with high case fatality following SARS-CoV-2 infection. Remdesivir alone and the combination of favipiravir and remdesivir increased the survival rate. Surprisingly, both imipenem and linezolid helped in the deterioration of disease outcome in the patients. A negative correlation was detected between increased mortality and the use of favipiravir and the use of either imipenem or linezolid. Among the compared antiviral regimens used in the treatment of severe COVID-19, remdesivir was found to be an effective antiviral that reduces COVID-19 case fatality. Antibiotic treatment using imipenem and/or linezolid should be carefully re-evaluated.

Favipiravir in the Treatment of Outpatient COVID-19: A Multicenter, Randomized, Triple-Blind, Placebo-Controlled Clinical Trial

BACKGROUND

Finding effective outpatient treatments to prevent COVID-19 progression and hospitalization is necessary and is helpful in managing limited hospital resources. Repurposing previously existing treatments is highly desirable. In this study, we evaluate the efficacy of Favipiravir in the prevention of hospitalization in symptomatic COVID-19 patients who were not eligible for hospitalization.

METHODS

This study was a triple-blind randomized controlled trial conducted between 5 December 2020 and 31 March 2021 in three outpatient centers in Isfahan, Iran. Patients in the intervention group received Favipiravir 1600 mg daily for five days, and the control group received a placebo. Our primary outcome was the proportion of hospitalized participants from day 0 to day 28. The outcome was assessed on days 3, 7, 14, 21, and 28 through phone calls.

RESULTS

Seventy-seven patients were randomly allocated to Favipiravir and placebo groups. There was no significant difference between groups considering baseline characteristics. During the study period, 10.5% of patients in the Favipiravir group and 5.1% of patients in the placebo group were hospitalized, but there was no significant difference between them (p-value = 0.3). No adverse event was reported in the treatment group.

CONCLUSIONS

Our study shows that Favipiravir did not reduce the hospitalization rate of mild to moderate COVID-19 patients in outpatient settings.

Efficacy and Safety of Favipiravir in Treating COVID-19 Patients: A Meta-Analysis of Randomized Control Trials

This meta-analysis was conducted with the aim to assess the safety and efficacy of favipiravir in treating patients with coronavirus disease 2019 (COVID-19). It was carried out in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We performed a thorough search of online databases including PubMed, EMBASE, and the Cochrane Library from their inceptions to November 30, 2022, using the following search terms: "Favipiravir" AND "COVID-19". We included randomized control trials (RCTs) that were conducted to determine the efficacy and safety of favipiravir for COVID-19. Efficacy outcomes assessed in this meta-analysis included time to viral clearance in days, time to clinical improvement in days, need for supplementary oxygen, and requirement of ICU admission. For safety outcomes, we compared overall adverse events and serious adverse events that had occurred during the treatment between the patients in the treatment group and the control group. Eight studies involving 1,448 patients were included in this meta-analysis. The results showed that no significant differences were found between the two groups in terms of time to viral clearance, time to clinical improvement, and the need for supplementary oxygen and ICU admission. In terms of safety, no significant differences were found between the two groups in relation to adverse events and serious adverse events. The current study found that favipiravir did not exert any beneficial impact on reducing ICU admission, the need for oxygen therapy, and time to viral clearance. However, a slight benefit was reported with regard to the time for clinical improvement, but it was insignificant between the two study groups.

Pharmacometrics: A New Era of Pharmacotherapy and Drug Development in Low- and Middle-Income Countries

Pharmacotherapy, in many cases, is practiced at a suboptimal level of performance in low- and middle-income countries (LMICs) although stupendous amounts of data are available regularly. The process of drug development is time-consuming, costly, and is also associated with loads of hurdles related to the safety concerns of the compounds. This review was conducted with the objective to emphasize the role of pharmacometrics in pharmacotherapy and the drug development process in LMICs for rational drug therapy. Pharmacometrics is widely applied for the rational clinical pharmacokinetic (PK) practice through the population pharmacokinetic (popPK) modeling and physiologically based pharmacokinetic (PBPK) modeling approach. The scope of pharmacometrics practice is getting wider day by day with the untiring efforts of pharmacometricians. The basis for pharmacometrics analysis is the computer-based modeling and simulation of pharmacokinetics/pharmacodynamics (PK/PD) data supplemented by characterization of important aspects of drug safety and efficacy. Pharmacometrics can be considered an invaluable tool not only for new drug development with maximum safety and efficacy but also for dose optimization in clinical settings. Due to the convenience of using sparse and routine patient data, a significant advantage exists in this regard for LMICs which would otherwise lag behind in clinical trials.

Comparative efficacy and safety of pharmacological interventions for severe COVID-19 patients: An updated network meta-analysis of 48 randomized controlled trials

BACKGROUND

To date, there has been little agreement on what drug is the "best" drug for treating severe COVID-19 patients. This study aimed to assess the efficacy and safety of different medications available at present for severe COVID-19.

METHODS

We searched databases for randomized controlled trials (RCTs) published up to February 28, 2022, with no language restrictions, of medications recommended for patients (aged 16 years or older) with severe COVID-19 infection. We extracted data on trials and patient characteristics, and the following primary outcomes: all-cause mortality (ACM), and treatment-emergent adverse events (TEAEs).

RESULTS

We identified 4021 abstracts and of these included 48 RCTs comprising 9147 participants through database searches and other sources. For decrease in ACM, we found that ivermectin/doxycycline, C-IVIG (i.e., a hyperimmune anti-COVID-19 intravenous immunoglobulin), methylprednisolone, interferon-beta/standard-of-care (SOC), interferon-beta-1b, convalescent plasma, remdesivir, lopinavir/ritonavir, immunoglobulin gamma, high dosage sarilumab (HS), auxora, and imatinib were effective when compared with placebo or SOC group. We found that colchicine and interferon-beta/SOC were only associated with the TEAEs of severe COVID-19 patients.

CONCLUSION

This study suggested that ivermectin/doxycycline, C-IVIG, methylprednisolone, interferon-beta/SOC, interferon-beta-1b, convalescent plasma (CP), remdesivir, lopinavir/ritonavir, immunoglobulin gamma, HS, auxora, and imatinib were efficacious for treating severe COVID-19 patients. We found that most medications were safe in treating severe COVID-19. More large-scale RCTs are still needed to confirm the results of this study.

Potential limitations in systematic review studies assessing the effect of the main intervention for treatment/therapy of COVID-19 patients: An overview

Background

Although several studies have assessed the safety, efficacy, and effectiveness of interventions in treating the COVID-19, many of them have limitations that can have an immense impact on their results. This study aims to assess the potential limitations in systematic reviews (SRs) that evaluate the effect of interventions on the treatment of the COVID-19.

Methods

PubMed, Scopus, and Web of Sciences (WOS) databases were searched from inception to January 1, 2022. All systematic reviews investigated the effectiveness, efficacy, safety, and outcome of the main intervention (Favipiravir, Remdesivir, Hydroxychloroquine, Ivermectin, Lopinavir/Ritonavir, or Tocilizumab) for the treatment of COVID-19 patients and reported the potential limitations of the included studies. We assessed the quality of the included studies using the Quality Assessment Tool (QAT) for review articles. We conducted a content analysis and prepared a narrative summary of the limitations.

Results

Forty-six studies were included in this review. Ninety one percent of the included studies scored as strong quality and the remaining (9%) as moderate quality. Only 29.7% of the included systematic reviews have a registered protocol. 26% of the included studies mentioned a funding statement. The main limitations of the included studies were categorized in 10 domains: sample size, heterogeneity, follow-up, treatment, including studies, design, definitions, synthesis, quality, and search.

Conclusion

Various limitations have been reported in all the included studies. Indeed, the existence of limitations in studies can affect their results, therefore, identifying these limitations can help researchers design better studies. As a result, stronger studies with more reliable results will be reported and disseminated. Further research on COVID-19 SRs is essential to improve research quality and also, efficiency among scientists across the world.

Early Treatment of Favipiravir in COVID-19 Patients Without Pneumonia: A Multicentre, Open-Labelled, Randomized Control Study

We investigated Favipiravir (FPV) efficacy in mild cases of COVID-19 without pneumonia and its effects towards viral clearance, clinical condition, and risk of COVID-19 pneumonia development. PCR-confirmed SARS-CoV-2-infected patients without pneumonia were enrolled (2:1) within 10 days of symptomatic onset into FPV and control arms. The former received 1800 mg FPV twice-daily (BID) on Day 1 and 800 mg BID 5-14 days thereafter until negative viral detection, while the latter received only supportive care. The primary endpoint was time to clinical improvement, defined by a National Early Warning Score (NEWS) of ≤1. 62 patients (41 female) comprised the FPV arm (median age: 32 years, median BMI: 22 kg/m²) and 31 patients (19 female) comprised the control arm (median age: 28 years, median BMI: 22 kg/m²). The median time to sustained clinical improvement, by NEWS, was 2 and 14 days for FPV and control arms respectively (adjusted hazard ratio (aHR) of 2.77, 95% CI 1.57-4.88, P < 0.001). The FPV arm also had significantly higher likelihoods of clinical improvement within 14 days after enrolment by NEWS (79% vs 32% respectively, P < 0.001), particularly female patients (aOR 6.35, 95% CI 1.49-27.07, P < 0.001). 8 (12.9%) and 7 (22.6%) patients in FPV and control arms developed mild pneumonia at a median (range) of 6.5 (1-13) and 7 (1-13) days after treatment, respectively (P = 0.316). All recovered well without complications. We can conclude that early treatment of FPV in symptomatic COVID-19 patients without pneumonia was associated with faster clinical improvement.Trial registration: Thai Clinical Trials Registry identifier: TCTR20200514001..

Favipiravir, camostat, and ciclesonide combination therapy in patients with moderate COVID-19 pneumonia with/without oxygen therapy: An open-label, single-center phase 3 randomized clinical trial

BACKGROUND

The effectiveness of combination therapy for COVID-19 pneumonia remains unclear. We evaluated favipiravir, camostat, and ciclesonide combination therapy in patients with moderate COVID-19 pneumonia.

METHODS

In this open-label phase 3 study, hospitalized adults who were positive for SARS-CoV-2 and had COVID-19 pneumonia were enrolled prior to official vaccination drive in Japan. Participants were randomly assigned to favipiravir monotherapy or favipiravir + camostat + ciclesonide combination therapy. The primary outcome was the length of hospitalization due to COVID-19 infection after study treatment. The hospitalization period was calculated from the time of admission to the time of patient discharge using the clinical management guide of COVID-19 for front-line healthcare workers developed by the Japanese Ministry of Health, Labour, and Welfare (Version 3). Cases were registered between November 11, 2020, and May 31, 2021. Japan Registry of Clinical Trials registration: jRCTs031200196.

FINDINGS

Of 121 enrolled patients, 56 received monotherapy and 61 received combination therapy. Baseline characteristics were balanced between the groups. The median time of hospitalization was 10 days for the combination and 11 days for the monotherapy group. The median time to discharge was statistically significantly lower in the combination therapy vs monotherapy group (HR, 1·67 (95% CI 1·03-2·7; P = 0·035). The hospital discharge rate was statistically significantly higher in the combination therapy vs monotherapy group in patients with less severe COVID-19 infections and those who were ≤60 years. There were no significant differences in clinical findings between the groups at 4, 8, 11, 15, and 29 days. Adverse events were comparable between the groups. There were two deaths, with one in each group.

INTERPRETATION

Combination oral favipiravir, camostat and, ciclesonide therapy could decrease the length of hospitalization stays without safety concerns in patients with moderate COVID-19 pneumonia. However, lack of hard clinical primary outcome is one of the major limitations of the study.

FUNDING

This research was supported by Japan Agency for Medical Research and Development (AMED) under Grant Number 20fk0108261h0001.

COVID 19: Airway Management and Pharmacological Strategies

Coronavirus disease 2019 caused by severe acute respiratory syndrome coronavirus 2 has since resulted in more than 250 million cases worldwide and over 50 million deaths. Although treatment is mainly supportive, with oxygen therapy being the mainstay, various pharmacological treatment modalities have also been explored. In this review, we have evaluated the available evidence on airway management as well as medical management and highlighted the possible interventions that may be effective in care of critically ill patients.

Supplemental Medicines-Nutritions Used by Health Personnel in their own Covid-19 Treatment Schedule

ABSTRACT OBJECTIVE. İn this study, with a view to investigate drug use behaviors of healthcare personnels who had Covid 19 infection in the first 1 year of the pandemic, it was aimed to determine the additional drugs and nutritional supplements they used in their own treatment. MATERIAL METHOD This is a descriptive cross-sectional study. The data were obtained through an online survey voluntarily completed under pandemic conditions by doctors, dentists, nurses, pharmacists and other health personnel who declared that they had Covid-19. RESULTS The study consisted of 405 individuals. 98% of healthcare personnels preferred to support their treatment. The medicines and herbal products that the participants started to use by their own decisions, without the advice of the physician who examined them, and the frequency of their use were vitamin C 53.3%, vitamin D 48.1%, acetylsalicylic acid 26.7%, paracetamol 23%, zinc 26.4%, multivitamin 19%, acetylcysteine 14.8%, famotidine 14.3%, subcutaneous heparin 12.6%. As for herbal products, inhaling thyme oil was noted in 11.6%, drinking thyme oil 10.1%, consuming ginger 14.3% of the participants. Non-prescription support products were found to be beneficial in 44.4%. CONCLUSION Almost all of the participants took a supplement with an intention to support the treatment. The fact that one out of two participants declared that they benefited from over-the-counter supplements reveals that further studies are needed to support the rational use of over-the-counter products in the treatment of Covid 19.

Real-World Experience with Favipiravir for the Treatment of Mild-to-Moderate COVID-19 in India

Background

Favipiravir, an RNA-dependent RNA polymerase inhibitor (RdRp), is a broad-spectrum oral antiviral agent approved in India under emergency use authorization, for the treatment of mild-to-moderate coronavirus disease (COVID-19). The present study was planned to evaluate the effectiveness and safety of favipiravir in real-world clinical practice.

Materials and Methods

This was a multicentric, retrospective, single-arm study conducted across four centres in India, after obtaining permission from the independent ethics committee. Medical records were analysed to evaluate effectiveness and safety of patients who were prescribed favipiravir.

Results

The medical records of a total of 360 patients met the inclusion criteria, with 358 of them available for the final analysis. Males made up 58.46% of the study population. The average age of enrolled patients was 51.80 ± 16.45 years. The most common symptoms were fever, cough, and myalgia-fatigue. The median time to clinical cure and fever relief was five and four days, respectively. The average length of stay in the hospital was six days. In total, 8% of the patients experienced adverse events. Hepatic enzyme elevation, diarrhoea, decreased appetite, headache, fatigue, and giddiness were the common symptoms.

Conclusion

In our real-world study, favipiravir was found to have a clinical cure rate of more than 90% in mild-to-moderate COVID-19 patients. This supports the use of favipiravir in the treatment of COVID-19. Favipiravir was well tolerated, with only minimal side effects, which were transient in nature.

The adenosine analog prodrug ATV006 is orally bioavailable and has preclinical efficacy against parental SARS-CoV-2 and variants

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus driving the ongoing coronavirus disease 2019 (COVID-19) pandemic, continues to rapidly evolve. Due to the limited efficacy of vaccination in prevention of SARS-CoV-2 transmission and continuous emergence of variants of concern (VOC), orally bioavailable and broadly efficacious antiviral drugs are urgently needed. Previously we showed that the parent nucleoside of remdesivir, GS-441524, possesses potent anti-SARS-CoV-2 activity. Herein, we report that esterification of the 5′-hydroxyl moieties of GS-441524 markedly improved antiviral potency. This 5′-hydroxyl-isobutyryl prodrug, ATV006, demonstrated excellent oral bioavailability in rats and cynomolgus monkeys and exhibited potent antiviral efficacy against different SARS-CoV-2 VOCs in vitro and in three mouse models. Oral administration of ATV006 reduced viral loads and alleviated lung damage when administered prophylactically and therapeutically to K18-hACE2 mice challenged with the Delta variant of SARS-CoV-2. These data indicate that ATV006 represents a promising oral antiviral drug candidate for SARS-CoV-2.

Antiviral Drug Discovery for the Treatment of COVID-19 Infections

The coronavirus disease 2019 (COVID-19) pandemic is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a recently emerged human coronavirus. COVID-19 vaccines have proven to be successful in protecting the vaccinated from infection, reducing the severity of disease, and deterring the transmission of infection. However, COVID-19 vaccination faces many challenges, such as the decline in vaccine-induced immunity over time, and the decrease in potency against some SARS-CoV-2 variants including the recently emerged Omicron variant, resulting in breakthrough infections. The challenges that COVID-19 vaccination is facing highlight the importance of the discovery of antivirals to serve as another means to tackle the pandemic. To date, neutralizing antibodies that block viral entry by targeting the viral spike protein make up the largest class of antivirals that has received US FDA emergency use authorization (EUA) for COVID-19 treatment. In addition to the spike protein, other key targets for the discovery of direct-acting antivirals include viral enzymes that are essential for SARS-CoV-2 replication, such as RNA-dependent RNA polymerase and proteases, as judged by US FDA approval for remdesivir, and EUA for Paxlovid (nirmatrelvir + ritonavir) for treating COVID-19 infections. This review presents an overview of the current status and future direction of antiviral drug discovery for treating SARS-CoV-2 infections, covering important antiviral targets such as the viral spike protein, non-structural protein (nsp) 3 papain-like protease, nsp5 main protease, and the nsp12/nsp7/nsp8 RNA-dependent RNA polymerase complex.

Sofosbuvir/Ledipasvir in Combination or Nitazoxanide Alone are Safe and Efficient Treatments for COVID-19 Infection: A Randomized Controlled Trial for Repurposing antivirals

Background and Study Aims

Currently, there is no therapy approved for COVID-19. We evaluated the efficacy and safety of sofosbuvir/ledipasvir and nitazoxanide for the treatment of patients with COVID-19 infection.

Patients and Methods

A multicenter, open-label randomized controlled trial included one hundred and ninety patients with non-severe COVID-19 infection. Patients were randomized into three groups. All groups received standard care supportive treatment (SCT). In addition, group 1 received sofosbuvir/ledipasvir, and group 2 received nitazoxanide. Follow-up by reverse-transcriptase polymerase chain reaction (RT-PCR) was done at intervals of 5, 8, 11, and 14 days. The primary endpoint was viral clearance.

Results

Viral clearance was significantly higher in the sofosbuvir/ledipasvir and nitazoxanide groups compared to the SCT group in all follow-up intervals (p < 0.001). In the sofosbuvir/ledipasvir arm, 36.9% showed early viral clearance by day 5. By day 14, 83.1% of the sofosbuvir/ledipasvir group, 39.7% of the nitazoxanide group, and 19.4% of the SCT group tested negative for SARS-CoV-2. Sofosbuvir/ledipasvir and nitazoxanide treatment were the only significant factors in Cox regression of negative RT-PCR with the highest OR (17.88, 95% CI: 6.66–47.98 and 2.59, 95% CI: 1.11–6.07, respectively). No mortality or serious adverse events were recorded.

Conclusion

The addition of sofosbuvir/ledipasvir or nitazoxanide to the SCT results in an early and high viral clearance rate in mild and moderate patients with COVID-19. These drugs represent a safe and affordable treatment for COVID-19.

Drug Repurposing for COVID-19: A Review and a Novel Strategy to Identify New Targets and Potential Drug Candidates

In December 2019, the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19) was first identified in the province of Wuhan, China. Since then, there have been over 400 million confirmed cases and 5.8 million deaths by COVID-19 reported worldwide. The urgent need for therapies against SARS-CoV-2 led researchers to use drug repurposing approaches. This strategy allows the reduction in risks, time, and costs associated with drug development. In many cases, a repurposed drug can enter directly to preclinical testing and clinical trials, thus accelerating the whole drug discovery process. In this work, we will give a general overview of the main developments in COVID-19 treatment, focusing on the contribution of the drug repurposing paradigm to find effective drugs against this disease. Finally, we will present our findings using a new drug repurposing strategy that identified 11 compounds that may be potentially effective against COVID-19. To our knowledge, seven of these drugs have never been tested against SARS-CoV-2 and are potential candidates for in vitro and in vivo studies to evaluate their effectiveness in COVID-19 treatment.

The efficacy and adverse effects of favipiravir on patients with COVID-19: A systematic review and meta-analysis of published clinical trials and observational studies

Objectives

This study aimed to evaluate the efficacy and adverse events of favipiravir in patients with COVID-19.

Methods

Our protocol was registered on PROSPERO (CRD42020206305). Fourteen databases were searched until February 8^th, 2021. An update search for new RCTs was done on March 2^nd, 2022. Meta-analysis was done for randomized controlled trials (RCTs) and non-RCTs.

Results

Overall, 157 studies (24 RCTs, 1 non-RCT, 21 observational studies, 2 case series, and 106 case reports) were included. On hospitalized patients, in comparison to standard of care, favipiravir showed a higher rate of viral clearance at day 5 (RR = 1.60, p = 0.02), defervescence at day 3–4 (RR = 1.99, p <0.01), chest radiological improvement (RR = 1.33, p <0.01), hospital discharge at day 10–11 (RR = 1.19, p <0.01), and shorter clinical improvement time (MD = –1.18, p = 0.05). Regarding adverse events, favipiravir groups had higher rates of hyperuricemia (RR = 9.42, p <0.01), increased alanine aminotransferase (RR = 1.35, p <0.01) but lower rates of nausea (RR = 0.42, p <0.01) and vomiting (R R= 0.19, p=0.02). There were no differences regarding mortality (RR=1.19, p=0.32), and increased aspartate aminotransferase (RR = 1.11, p = 0.25). On nonhospitalized patients, no significant differences were reported.

Conclusions

Adding favipiravir to the standard of care provides better outcomes for hospitalized patients with COVID-19. Pregnant, lactating women, and patients with a history of hyperuricemia should avoid using favipiravir.

A global picture: therapeutic perspectives for COVID-19

The COVID-19 pandemic is a lethal virus outbreak by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), which has severely affected human lives and the global economy. The most vital part of the research and development of therapeutic agents is to design drug products to manage COVID-19 efficiently. Numerous attempts have been in place to determine the optimal drug dose and combination of drugs to treat the disease on a global scale. This article documents the information available on SARS-CoV-2 and its life cycle, which will aid in the development of the potential treatment options. A consolidated summary of several natural and repurposed drugs to manage COVID-19 is depicted with summary of current vaccine development. People with high age, comorbity and concomitant illnesses such as overweight, metabolic disorders, pulmonary disease, coronary heart disease, renal failure, fatty liver and neoplastic disorders are more prone to create serious COVID-19 and its consequences. This article also presents an overview of post-COVID-19 complications in patients.

A global picture: therapeutic perspectives for COVID-19

The COVID-19 pandemic is a lethal virus outbreak by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), which has severely affected human lives and the global economy. The most vital part of the research and development of therapeutic agents is to design drug products to manage COVID-19 efficiently. Numerous attempts have been in place to determine the optimal drug dose and combination of drugs to treat the disease on a global scale. This article documents the information available on SARS-CoV-2 and its life cycle, which will aid in the development of the potential treatment options. A consolidated summary of several natural and repurposed drugs to manage COVID-19 is depicted with summary of current vaccine development. People with high age, comorbity and concomitant illnesses such as overweight, metabolic disorders, pulmonary disease, coronary heart disease, renal failure, fatty liver and neoplastic disorders are more prone to create serious COVID-19 and its consequences. This article also presents an overview of post-COVID-19 complications in patients.

Evaluation of favipiravir in the treatment of COVID-19 based on the real-world

BACKGROUND

The role of favipiravir (FVP) as a COVID-19 treatment is recognized but not fully elucidated. We aimed to evaluate whether FVP has definite clinical efficacy and safety in the treatment of COVID-19.

METHODS

International and Chinese databases were searched for randomized controlled clinical trials evaluating FVP for the treatment of COVID-19. A meta-analysis was performed and published literature was synthesized to evaluate the corresponding therapeutic effects.

RESULTS

We included 13 studies (1430 patients in total). Meta-analysis showed that patients with mild-to-moderate disease treated with FVP had a significantly higher viral clearance rate than those in the control group 10 and 14 days after initiation of treatment [RR: 1.13 (95% CI: 1.00, 1.28), P = 0.04; I² = 39% for day 10 and RR: 1.16 (95% CI: 1.04, 1.30), P = 0.008; I² = 38% for day 14] and a significantly shorter hospital stay [MD: -1.52 (95% CI: -2.82, -0.23), P = 0.02; I² = 0%].

CONCLUSIONS

FVP significantly promotes viral clearance and reduces the hospitalization duration in mild-to-moderate COVID-19 patients, which can reduce the risk of severe disease outcomes in patients. However, more importantly, the results showed no benefit of FVP in severe patients, and caution should be taken regarding the treatment options of FVP in severe patients.

Pulmonary embolism after dexamethasone treatment for COVID-19: a case report

Background

Although the RECOVERY trial showed that dexamethasone was efficacious for the treatment of coronavirus disease 2019 (COVID-19), its impact on the risk of pulmonary embolism (PE) and other serious procoagulant events was not assessed.

Case presentation

Here we report the case of a previously healthy 83-year-old woman with COVID-19, without any genetic predisposition to thrombosis. She developed moderate respiratory distress 12 days after symptom onset and a 10-day course of dexamethasone therapy was initiated. Her clinical condition and imaging findings improved initially; however, they deteriorated after the completion of dexamethasone therapy, despite the improvement in her pneumonia and viral clearance. Laboratory tests showed markedly raised serum D-dimer, ferritin, and sIL-2R levels, and contrast-enhanced computed tomography showed deep vein thrombosis (DVT) in the left iliac vein and PE of the right pulmonary artery. The DVT and PE were successfully treated using intravenous heparin administration.

Conclusions

This case illustrates the potential risk of rebound inflammation and procoagulant events following dexamethasone withdrawal. We believe that COVID-19-induced DVT and PE can be affected by dexamethasone therapy. Although dexamethasone reduces procoagulant factors, increases anticoagulant factors, and modulates cytokines, which can suppress/delay thrombus formation during treatment, it confers the risk for rebound cytokine production after treatment completion, triggering cytokine and coagulation cascades that can lead to thromboembolic diseases. In this critical clinical period, the patient’s deteriorating condition may be overlooked because of the masking effects of dexamethasone treatment on fever and other clinical conditions and laboratory changes. Clinicians should follow-up coagulation markers carefully and contrast-enhanced computed tomography is useful for detecting coagulation; and, if PE occurs, therapeutic heparin administration is essential because emboli can also generate cytokines.

Efficacy and safety of favipiravir plus interferon-beta versus lopinavir/ritonavir plus interferon-beta in moderately ill patients with COVID-19: A randomized clinical trial

Favipiravir (FVP), lopinavir/ritonavir (LPV/RTV), and interferon‐beta (INF‐beta) are considered as potential treatments for COVID‐19. We examined the efficacy and safety of FVP and INF‐beta compared to LPV/RTV and INF‐beta combinations for the treatment of SARS‐CoV‐2. It was a single‐center randomized clinical trial. Eligible patients were randomized to receive FVP plus INF‐beta versus LPV/RTV plus INF‐beta. The primary endpoint was the viral clearance after seven days of randomization. ICU admission, length of stay (LOS) in hospital, in‐hospital mortality, and the incidence of adverse events were also measured. This trial was registered on the Iranian Registry of Clinical Trials (IRCT20200506047323N3). Patients were randomly allocated to the FVP (n = 33) and LPV/RTV (n = 33) groups. The viral clearance on Day seven was not significantly different between the FVP (31.1%) and the LPV/RTV groups (16.1%). The rate of ICU admission and likewise the in‐hospital mortality in the FVP group (12.5% and 6.3%, respectively) were similar to the LPV/RTV groups (19.4% and 19.4%, respectively). The median LOS in the hospital was also not different (6.8 days [interquartile range; IQR = 5.0–11.0] in the FVP and (8.0 days [IQR = 5.5–12.5]) in LPV/RTV groups (p = 0.140). Adverse events were observed in 25.0% of FVP and 32.3% of LPV/RTV groups. The combination therapy with FVP did not exert a higher efficacy compared to the combination regimen of LPV/RTV. However, both treatment regimens demonstrated a mild profile of adverse events.

Strategies for fighting pandemic virus infections: Integration of virology and drug delivery

Respiratory viruses have sometimes resulted in worldwide pandemics, with the influenza virus and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) being major participants. Long-term efforts have made it possible to control the influenza virus, but seasonal influenza continues to take many lives each year, and a pandemic influenza virus sometimes emerges. Although vaccines for coronavirus disease 2019 (COVID-19) have been developed, we are not yet able to coexist with the SARS-CoV-2. To overcome such viruses, it is necessary to obtain knowledge about international surveillance systems, virology, ecology and to determine that immune responses are effective. The information must then be transferred to drugs. Delivery systems would be expected to contribute to the rational development of drugs. In this review, virologist and drug delivery system (DDS) researchers discuss drug delivery strategies, especially the use of lipid-based nanocarriers, for fighting to respiratory virus infections.

Favipiravir in the Battle with Respiratory Viruses

Abstract:

Among antiviral drugs, the vast majority targets only one or two related viruses. The conventional model, one virus - one drug, significantly limits therapeutic options. Therefore, in the strategy of controlling viral infections, there is a necessity to develop compounds with pleiotropic effects. Favipiravir (FPV) emerged as a strong candidate to become such a drug. The aim of the study is to present up-to-date information on the role of favipiravir in the treatment of viral respiratory infections. The anti-influenza activity of favipiravir has been confirmed in cell culture experiments, animal models and clinical trials. Thoroughly different - from the previously registered drugs - mechanism of action suggests that FVP can be used as a countermeasure for the novel or re-emerging influenza virus infections. In recent months, favipiravir has been broadly investigated due to its potential efficacy in the treatment of Covid-19. Based on preclinical and clinical studies and a recently published meta-analysis it seems that favipiravir may be a promising antiviral drug in the treatment of patients with Covid-19. FPV is also effective against other RNA respiratory viruses and may be a candidate for the treatment of serious infections caused by human rhinovirus, respiratory syncytial virus, metapneumovirus, parainfluenza viruses and hantavirus pulmonary syndrome.

Overview of Clinical Outcome and Therapeutic Effectiveness of Favipiravir in Patients with COVID-19 Admitted to Intensive Care Unit, Riyadh, Saudi Arabia

Background

Prior to the availability of the current COVID-19 vaccine, the need to control the pandemic worldwide was focused on management of the disease using previously approved antivirals, including Favipiravir which inhibits viral replication through the RNA dependent RNA polymerase enzyme. Favipiravir’s efficacy against different viral infections has made it a potential treatment for COVID-19. We are aiming in this study to assess the therapeutic efficacy and safety of Favipiravir in treating critically ill patients admitted with COVID-19 to Intensive Care Units (ICUs).

Methods

This is a retrospective cohort study was conducted in five tertiary hospitals in Riyadh, Kingdom of Saudi Arabia (KSA). The studied sample was randomized from a huge pool of data collected primarily for critically ill COVID-19 patients admitted to (ICUs) during the period between April 2020 to March 2021. Two groups of patients matched 1: 1 for age and body mass index (BMI) was enrolled in the study; one group received Favipiravir and another comparison group received other antimicrobial medications, not including Favipiravir.

Results

A total data of 538 COVID-19 patients were analyzed, 269 (50.%) received Favipiravir and 269 (50%) the control group received different treatments. More than two-thirds 201 (74.7%) were Saudi citizens, the majority 177 (65.8%) were males and the mean age and (BMI) were; (57.23 ± 15.16) years and (31.61 ± 7.33) kg/m2 respectively. The most frequent symptoms of presentation were shortness of breath (SOB), fever, and cough, and the most frequent comorbidity was diabetes mellitus, hypertension, and ischemic heart disease.

In the supplemental therapy, corticosteroid, tocilizumab and chloroquine were statistically significant (P = 0.001) when combined in the FVP group more than in the comparison group. Severe acute respiratory distress syndrome (ARDS) was more frequent among Favipiravir group, while the overall mortality rate among the Favipiravir group was not statistically significant (p-value 0.4).

Conclusion

According to the study’s results revealing FVP is not superior to other antivirals, patients who received Favipiravir presented with more severe symptoms, more comorbidities, more complications, and is not effective in controlling the cytokine storm which negatively impact the efficacy of Favipiravir.

FVP therapy had no influence on ICU and hospital length of stay in comparison with the control group as well as in the overall mortality rate among the FVP group was not statistically significant. further research is needed to understand how FVP along with other treatments can improve the length of stay among COVID-19 patients admitted to the ICU.

DrugDevCovid19: An Atlas of Anti-COVID-19 Compounds Derived by Computer-Aided Drug Design

Since the outbreak of SARS-CoV-2, numerous compounds against COVID-19 have been derived by computer-aided drug design (CADD) studies. They are valuable resources for the development of COVID-19 therapeutics. In this work, we reviewed these studies and analyzed 779 compounds against 16 target proteins from 181 CADD publications. We performed unified docking simulations and neck-to-neck comparison with the solved co-crystal structures. We computed their chemical features and classified these compounds, aiming to provide insights for subsequent drug design. Through detailed analyses, we recommended a batch of compounds that are worth further study. Moreover, we organized all the abundant data and constructed a freely available database, DrugDevCovid19, to facilitate the development of COVID-19 therapeutics.

The Saudi Critical Care Society practice guidelines on the management of COVID-19 in the ICU: Therapy section

BACKGROUND

The rapid increase in coronavirus disease 2019 (COVID-19) cases during the subsequent waves in Saudi Arabia and other countries prompted the Saudi Critical Care Society (SCCS) to put together a panel of experts to issue evidence-based recommendations for the management of COVID-19 in the intensive care unit (ICU).

METHODS

The SCCS COVID-19 panel included 51 experts with expertise in critical care, respirology, infectious disease, epidemiology, emergency medicine, clinical pharmacy, nursing, respiratory therapy, methodology, and health policy. All members completed an electronic conflict of interest disclosure form. The panel addressed 9 questions that are related to the therapy of COVID-19 in the ICU. We identified relevant systematic reviews and clinical trials, then used the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach as well as the evidence-to-decision framework (EtD) to assess the quality of evidence and generate recommendations.

RESULTS

The SCCS COVID-19 panel issued 12 recommendations on pharmacotherapeutic interventions (immunomodulators, antiviral agents, and anticoagulants) for severe and critical COVID-19, of which 3 were strong recommendations and 9 were weak recommendations.

CONCLUSION

The SCCS COVID-19 panel used the GRADE approach to formulate recommendations on therapy for COVID-19 in the ICU. The EtD framework allows adaptation of these recommendations in different contexts. The SCCS guideline committee will update recommendations as new evidence becomes available.

Clinical, demographic, and laboratory characteristics of COVID -19 infection and risk of in-hospital mortality. A single center 4

Background:

Frequent waves of corona virus disease (COVID-19) and lack of specific drugs against that, warrant studies to reduce the morbidity and mortality of this pandemic disease. In this study, we investigated the association between influenza vaccination and the severity and outcome of COVID-19 disease in Iranian patients living in the North.

Methods:

This retrospective case-control study was performed on186 patients with COVID-19 infection between March and April, 2020. Patients with positive PCR were divided into two groups of case and control; Patients with moderate to severe and normal to mild lung involvement, respectively. The lung opacities in all of the 5 lobes were evaluated on chest CT images using a CT severity scoring system. The history of influenza vaccination during the fall of 2019-2020 was determined by a phone call. Statistical analysis was done using the chi-square test, student’s t-test, and logistic regression. The significance level was p<0.05.

Results:

The mean age of patients was 54.67±15.05years. Most patients had pulmonary manifestations including ground-glass opacity (57%), consolidation (80%) and pleural effusion (3.2%). Adjusting for age, gender, and history of underlying disease, vaccination is an effective factor in the severity of pulmonary involvement (AOR=0.39; 95%CI: (0.21, 0.73); P=0.003). Furthermore, the chance of ICU admission decreased via influenza vaccination (OR=0.21, P=0.001).

Conclusion:

The results showed that the severity of COVID-19 pulmonary involvement and outcome as ICU admission, and severe symptoms in patients with history of influenza vaccination were significantly lower than those without history of vaccination. This strategy can be used to prevent and reduce the complications of COVID-19.

Effects of hydroxychloroquine and favipiravir on clinical course in outpatients with COVID-19

Background/aim

Due to the importance of early outpatient treatment to prevent hospitalization and disease progression, we examined the effects of hydroxychloroquine and favipiravir, which were initiated in early period, on the clinical course of COVID-19 outpatients.

Materials and methods

Data of confirmed COVID-19 outpatients over a 4-month period were analyzed retrospectively. Public Health Management System (HSYS) was used for the case-based follow-up. Patients on antiviral therapy for at least five days, including hydroxychloroquine and / or favipiravir and patients who were followed-up for 30 days were included in this analysis.

Results

We enrolled 1489 patients in this study. Overall, 775 (52%) patients were male and a mean age of patients was 38.9 ± 11.1 years. Of these patients, 537 of them were received favipiravir, 545 of them were received hydroxychloroquine and 407 of them were received both favipiravir and hydroxychloroquine. Symptoms improvement on the 14th day of follow-up was 1.8 times higher in the group of patients receiving hydroxychloroquine compared to patients who received favipiravir (p = 0.003). On the 3rd day of follow- up, PCR negativity rate was higher in patients who received hydroxychloroquine (p = 0.004). Hospitalization rates were similar in patients receiving favipiravir and hydroxychloroquine (p = 0.144). However, in the presence of pneumonia at the time of diagnosis, the hospitalization rate was 6.6 times higher in patients who received favipiravir than those who received hydroxychloroquine.

Conclusion

The subgroups of patients treated with hydroxychloroquine and/or favipiravir did not have similar disease severities in our study. Therefore, further studies with homogeneous patient groups to be arranged prospectively are needed.

The safety profile of favipiravir in COVID-19 patients with severe renal impairment

OBJECTIVE

The safety profile of favipiravir in patients with severe renal impairment has not been investigated and available data are insufficient. The study aimed to compare the incidence of favipiravir-associated adverse events amongst patients with varying renal function statuses.

METHODS

Records of 921 patients who were hospitalised for COVID-19 and had received at least 5 days of favipiravir treatment were retrospectively evaluated and 228 patients were included in the study. Patients' age, sex, comorbidities, estimated glomerular filtration rate (eGFR) and haematological and biochemical values were recorded. The incidence of adverse events was compared with the age, sex, comorbidities and eGFR of the patients.

RESULTS

The mean age of the patients was 59.3 ± 15.6 years, and 38.2% of the patients were women. One hundred and thirty-one (57.5%) patients had experienced adverse events. These adverse effects consisted of ALT elevation (35.5%), AST elevation (21.5%), anaemia (16.2%), hyperuricaemia (10.5%), hepatocellular injury (9.2%), neutropenia (3.5%) and thrombocytopenia (2.6%). The incidence of adverse events was not significantly different when patients had eGFR >60 mL/min/1.73 m² or eGFR 30-60 mL/min/1.73 m² (P > .05), but significantly increased when the eGFR dropped to <30 (P < .05). The differences seen with hyperuricaemia and anaemia were significant (P < .05).

CONCLUSION

Even though favipiravir appeared to be well tolerated in the individuals with renal failure in this study, its use in this population remains a challenge that requires more research and analysis.

Pharmacological Treatment Options for Coronavirus Disease-19 in Renal Patients

Patients with chronic kidney disease (CKD), including dialysis and transplant patients, are at greater risk of contracting SARS-CoV-2 due to kidney dysfunction and preexisting comorbidities. To date, a specific guideline on managing these high-risk patients infected with COVID-19 has not been established. As the current management of COVID-19 comprises mainly experimental drugs, the authors aim to provide information on dosing adjustments at different stages of kidney dysfunction and notable renal side effects. We performed a nonsystematical review of currently available COVID-19 drugs exploring several different clinical trial databases and search browsers. Several antivirals and monoclonal antibodies used in COVID-19 treatment require dosage adjustments in kidney dysfunction. In a global pandemic setting, nephrologists need to consider the appropriate dosage according to the renal function and closely monitor the side effects of different drug combinations to obtain the optimum therapeutic effect while avoiding further renal damage. Further studies are required to determine the safety and efficacy of these drugs in renal patients.

Efficacy of Early Treatment with Favipiravir on Disease Progression among High Risk COVID-19 Patients: A Randomized, Open-Label Clinical Trial

BACKGROUND

Role of favipiravir in preventing disease progression in COVID-19 remains uncertain. We aimed to determine its effect in preventing disease progression from non-hypoxia to hypoxia among high risk COVID-19 patients.

STUDY DESIGN

This was an open-label, randomized clinical trial conducted at 14 public hospitals across Malaysia from February to June 2021 among 500 symptomatic, RT-PCR confirmed COVID-19 patients, aged ≥50 years with ≥1 co-morbidity, and hospitalized within first 7 days of illness. Patients were randomized on 1:1 ratio to favipiravir plus standard care or standard care alone. Favipiravir was administered at 1800mg twice-daily on day 1 followed by 800mg twice-daily until day 5. The primary endpoint was rate of clinical progression from non-hypoxia to hypoxia. Secondary outcomes included rates of mechanical ventilation, intensive care unit (ICU) admission, and in-hospital mortality.

RESULTS

Among 500 patients were randomized (mean age, 62.5 [SD 8.0] years; 258 women [51.6%]; and 251 [50.2%] had COVID-19 pneumonia), 487 (97.4%) patients completed the trial. Clinical progression to hypoxia occurred in 46 (18.4%) patients on favipiravir plus standard care and 37 (14.8%) on standard care alone (OR 1.30; 95%CI, 0.81-2.09; P=.28). All three pre-specified secondary end points were similar between both groups. Mechanical ventilation occurred in 6 (2.4%) vs 5 (2.0%) (OR 1.20; 95%CI, 0.36-4.23; P=.76), ICU admission in 13 (5.2%) vs 12 (4.8%) (OR 1.09; 95%CI, 0.48-2.47; P=.84), and in-hospital mortality in 5 (2.0%) vs 0 (OR 12.54; 95%CI, 0.76- 207.84; P=.08).

CONCLUSIONS

Among COVID-19 patients at high risk of disease progression, early treatment with oral favipiravir did not prevent their disease progression from non-hypoxia to hypoxia.

Elevated blood favipiravir levels are inversely associated with ferritin levels and induce the elevation of uric acid levels in COVID-19 treatment: A retrospective single-center study

Introduction

Measurement of blood Favipiravir (FPV) levels and accumulation of data in COVID-19 patients are critical for assessing FPV efficacy and safety. We performed a retrospective study based on measurements of blood levels of FPV and related factors in COVID-19 patients admitted to our hospital. Furthermore, we also investigated the association between blood FPV levels and uric acid level alterations before and after FPV administration.

Methods

We enrolled 27 COVID-19 patients who had received FPV treatment at Hokushin General Hospital from April 1 to December 31, 2020. Age, gender, COVID-19 severity, presence of comorbidities, and laboratory data for each subject were investigated to identify factors that correlate with blood FPV levels. Uric acid levels were measured before and after FPV administration and a difference between the levels (i.e., a change of uric acid level) was evaluated.

Results

When a significant univariate variable was input by the stepwise method and a combination of variables that maintained statistical superiority was searched, serum ferritin was the only factor that independently affected blood FPV level. Furthermore, in the high-FPV group (20 μg/mL or more), a significant increase in uric acid levels was observed after FPV administration. The increment value was significantly larger than that in the low-FPV group (less than 20 μg/mL).

Conclusions

Ferritin level was an important independent factor inversely affecting blood FPV level. Furthermore, a high blood FPV level induced the elevation of uric acid levels in COVID-19 treatment.

Overview of potential drugs for the treatment of new coronavirus Infection (COVID-19)

The new coronavirus infection (SARS-CoV-2), better known as COVID-19, quickly evolved into a worldwide pandemic with a significant public health burden. Currently, there are no approved drugs or preventive therapeutic strategies to combat infection. Decisions about prescribing many medications are made based on the results obtained in in vitro studies, or expert opinions. Most of the drugs currently used to treat COVID-19 are approved antivirals or antibodies against other diseases. However, there are hundreds of clinical studies underway around the world to discover effective treatments for COVID-19. This article summarizes the results of clinical studies of potential therapeutic drugs used as COVID-19 therapy. Based on this review, it can be concluded that there is still no high-quality evidence to support any of the drugs described below. Until the unambiguous results of randomized controlled trials are available, the use of any of the following drugs is not clinically proven as an effective treatment for COVID-19.

Favipiravir versus standard of care in patients with severe COVID-19 infections: A retrospective comparative study

Objective

To assess the efficacy of Favipiravir compared to the standard therapy in treating patients with severe COVID-19 infection.

Methods

This is a retrospective cohort of patients with COVID-19 pneumonia who were treated with favipiravir, versus comparison group that received the standard of care.

Results

A total of 226 patients were included; 110 patients received favipiravir and 116 patients received standard of care. Patients who received favipiravir had longer time to recovery (14.2 ± 8.8 versus 12.8 ± 5.2, p = 0.17). Favipiravir was associated with an improved early day 14 mortality (4 [3.6%] versus 11 [9.5%]), p = 0.008), but was associated with a higher day 28 mortality (26 [23.6%] versus 11 [9.5%], p = 0.02). The overall mortality was higher in the favipiravir versus the standard of care group but difference was not statistically significant (33 [30.0%] versus 24 [20.7%], p = 0.10).

Conclusion

The addition of favipiravir to standard of care was not associated with any improvement in clinical outcomes or mortality. Larger randomized controlled clinical trials are needed to further assess the efficacy of favipiravir.

Antiviral Therapeutic Approaches for SARS-CoV-2 Infection: A Systematic Review

Due to the lack of an etiologic treatment for SARS-CoV-2 and the difficulties involved in developing new drugs, some drugs already approved for other diseases or with efficacy against SARS and MERS, have been used in patients with COVID-19. This systematic review aims to summarize evidence on the efficacy and safety of five antivirals applied to patients with COVID-19, that have proven to be effective either in vitro studies or in studies on SARS-CoV and MERS.; An intensive search of different databases (Pub Med, WoS, MEDLINE and Cochrane COVID-19 Study Register) has been carried out until the end of April 2021. This systematic review has been conducted according to the PRISMA statement. From each of the included studies, the characteristics of the intervention and comparison groups, demographic data and results were extracted independently; Remdesivir is well tolerated and helps to accelerate clinical improvement but is ineffective in reducing mortality. Favipiravir is safe and shows promising results regarding symptom resolution but does not improve viral clearance. The use of lopinavir/ritonavir has been associated with an increased risk of gastrointestinal adverse events and it has not proven to be effective. No significant differences were observed between patients treated with ribavirin or umifenovir and their respective control groups; Remdesivir and favipiravir are well tolerated and effective in accelerating clinical improvement. This systematic review does not support the use of lopinavir/ritonavir, ribavirin and umifenovir in hospitalized patients with COVID-19.