Combination of (interferon beta-1b, lopinavir/ritonavir and ribavirin) versus favipiravir in hospitalized patients with non-critical COVID-19: A cohort study

Abstract

IFNs antiviral effect is achieved through the activation of interferon-stimulated genes (ISGs) which encode protein products that work alone or in combinations to achieve one or more cellular outcomes, including antiproliferative activities, antiviral defense, and stimulation of adaptive immunity [3]. Because of the importance of endogenous IFNs in early viral infections control, there has been several studies examining its use in therapeutic regimens for coronavirus infections as early as 2004 [4, 5]. [...]other antivirals have been examined in COVID-19. [...]ribavirin (RBV), a guanosine analogue and a broad-spectrum antiviral drug, has been evaluated in patients with MERS-CoV and SARS-CoV and later had high half maximal effective concentration (EC50) of 109.50 μM and selectivity index against SARS-CoV-2 in Vero cells [10]. To the best of our knowledge, there is no study to date comparing FPV to IFN-based regimens in the treatment of COVID-19. [...]we aimed to evaluate the safety and efficacy of triple combination regimen of LPV/r, RBV and IFN β-1b, in comparison with FPV in the treatment of patients hospitalized with mild, moderate, and severe COVID-19 using an observational cohort study design, where treatment allocation was based on changes to national treatment protocols rather than physicians’ selection (quasi-experimental).

About the Authors:

Areej A. Malhani

Roles Conceptualization, Data curation, Validation, Writing – original draft, Writing – review & editing

Affiliation: Clinical Pharmacy Department, Pharmacy Services Administration, King Fahad Medical City, Riyadh, Saudi Arabia

Mushira A. Enani

Contributed equally to this work with: Mushira A. Enani, Fatemeh Saheb Sharif-Askari

Roles Conceptualization, Data curation, Validation, Writing – original draft, Writing – review & editing

Affiliation: Infectious Diseases Section, Department of Medical Specialties, King Fahad Medical City, Riyadh, Saudi Arabia

Fatemeh Saheb Sharif-Askari

Contributed equally to this work with: Mushira A. Enani, Fatemeh Saheb Sharif-Askari

Roles Conceptualization, Formal analysis, Methodology, Writing – original draft, Writing – review & editing

Affiliation: Sharjah Medical Institute of Research, College of Medicine, University of Sharjah, Sharjah, United Arab Emirates

Mona R. Alghareeb

Roles Conceptualization, Data curation, Validation, Writing – original draft, Writing – review & editing

Affiliation: Clinical Research Coordinator, Collage of Medicine, King Fahad Medical City, Riyadh, Saudi Arabia

Roaa T. Bin-Brikan

Roles Conceptualization, Data curation, Validation, Writing – original draft, Writing – review & editing

Affiliation: Clinical Research Coordinator, Collage of Medicine, King Fahad Medical City, Riyadh, Saudi Arabia

Safar A. AlShahrani

Roles Conceptualization, Data curation, Validation, Writing – original draft, Writing – review & editing

Affiliation: Outpatient Pharmacy Department, Pharmacy Services Administration, King Fahad Medical City, Riyadh, Saudi Arabia

Rabih Halwani

Roles Conceptualization, Investigation, Methodology, Writing – original draft, Writing – review & editing

Affiliations Sharjah Medical Institute of Research, College of Medicine, University of Sharjah, Sharjah, United Arab Emirates, Department of Clinical Sciences, College of Medicine, University of Sharjah, Sharjah, United Arab Emirates, Prince Abdullah Ben Khaled Celiac Disease Chair, Department of Pediatrics, Faculty of Medicine, King Saud University, Saudi Arabia

Imad M. Tleyjeh

Roles Conceptualization, Data curation, Formal analysis, Funding acquisition, Investigation, Methodology, Project administration, Resources, Software, Supervision, Validation, Visualization, Writing – original draft, Writing – review & editing

* E-mail: [email protected]

Affiliations Infectious Diseases Section, Department of Medical Specialties, King Fahad Medical City, Riyadh, Saudi Arabia, College of Medicine, Alfaisal University, Riyadh, Saudi Arabia, Division of Infectious Diseases, Mayo Clinic College of Medicine and Science, Rochester, Minnesota, United States of America, Division of Epidemiology, Mayo Clinic College of Medicine and Science, Rochester, Minnesota, United States of America

ORCID logo https://orcid.org/0000-0002-5551-0353

Introduction

The pandemic of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has resulted in more than 100 million cases and over 2 million deaths worldwide as of February 16, 2021 [1]. Despite the huge global death toll, there is a paucity of approved treatment options which include the antiviral medication remdesivir with or without baricitinib, and dexamethasone. Other potential antiviral treatments such as favipiravir (FPV) and interferon (IFN) based therapy have had conflicting results in randomized controlled trials (RCTs) and are not currently endorsed for COVID-19 treatment by medical societies [2].

Type I IFNs, first discovered in 1957, are well known cytokines which play an important role in both innate and cell-mediated immunity against viral infections. IFNs antiviral effect is achieved through the activation of interferon-stimulated genes (ISGs) which encode protein products that work alone or in combinations to achieve one or more cellular outcomes, including antiproliferative activities, antiviral defense, and stimulation of adaptive immunity [3]. Because of the importance of endogenous IFNs in early viral infections control, there has been several studies examining its use in therapeutic regimens for coronavirus infections as early as 2004 [4, 5].

Moreover, other antivirals have been examined in COVID-19. The protease inhibitor lopinavir/ritonavir (LPV/r), demonstrated inhibition of MERS-CoV and SARS-CoV replication in vitro. Early during the pandemic, the available data for the use of LPV/r in COVID-19 was controversial and varied from studies with clearly negative results to more favorable efficacy.

Early RCTs [6–8] reports on the management of COVID-19 in-patients with combination LPV/r or placebo did not show a beneficial effect on mortality or the need for mechanical ventilation. Subsequently, the SOLIDARITY trial was stopped due to preliminary results showing that LPV/r produce no reduction in the mortality of COVID-19 hospitalized patients when compared to standard of care [9]. Second, ribavirin (RBV), a guanosine analogue and a broad-spectrum antiviral drug, has been evaluated in patients with MERS-CoV and SARS-CoV and later had high half maximal effective concentration (EC50) of 109.50 μM and selectivity index against SARS-CoV-2 in Vero cells [10].

One of the first RCTs conducted during the pandemic was a phase 2 multicenter trial in hospitalized adult patients with COVID-19 in Hong Kong. Patients were allocated to a 14-days combination of LPV/r, ribavirin (RBV) and IFN β-1b (triple combination therapy) vs. 14 days of LPV/r. Triple antiviral therapy was more effective in comparison to LPV/r in symptoms resolution, duration of viral shedding and length of hospitalization in patients with mild to moderate COVID-19 [11].

Another antiviral drug, FPV, a competitive inhibitor of RNA-dependent RNA polymerase (RdRp), which was first approved in Japan for treating influenza, has also been examined in COVID-19. The US Food and Drug Administration has approved it as an investigational new drug to proceed with an expanded phase 2 clinical trial for COVID-19. Experimental studies have demonstrated that FPV can achieve an effective antiviral concentration against the SARS-CoV-2 virus within a safe therapeutic dose. Many countries have recommended the usage of FPV therapy in mild to moderate COVID-19 such as Japan, India, Russia, Thailand, Kenya and Saudi Arabia [12, 13]. However, a recent systematic review by the EUnetHTA Rolling Collaborative Review Authoring Team showed that the existing evidence does not support the use of FPV as monotherapy or combination therapy for COVID-19 [14].

To the best of our knowledge, there is no study to date comparing FPV to IFN-based regimens in the treatment of COVID-19. Therefore, we aimed to evaluate the safety and efficacy of triple combination regimen of LPV/r, RBV and IFN β-1b, in comparison with FPV in the treatment of patients hospitalized with mild, moderate, and severe COVID-19 using an observational cohort study design, where treatment allocation was based on changes to national treatment protocols rather than physicians’ selection (quasi-experimental).

Materials and methods

Study setting

Our study is a quasi-experimental comparative study of a prospective cohort of patients with mild to severe COVID-19 that were admitted to King Fahad Medial City (KFMC), the largest tertiary and teaching hospital under the Ministry of Health (MOH), in Saudi Arabia. KFMC is a Joint Commission International (JCI) accredited hospital, has been assigned by the MOH as a COVID-19 community treating center for the central region of Saudi Arabia. Allocation of patients to FPV or triple IFN-based combination regimen was non-random but based on a “quasi-experimental” natural experiment design due to the introduction of FPV in Saudi national COVID-19 treatment guidelines and its availability at KFMC by mid-June 2020. Neither physicians nor patients influenced the allocation of patients to treatment groups except within the context of the institutional treatment protocol. Triple IFN-based combination regimen was used prior to mid-June 2020 whereas FPV was used later on (Fig 1). KFMC Institutional Review Board (IRB) approved the study and waived the need for informed consent.

[Figure omitted. See PDF.]

Fig 1. Distribution of treatment modalities over time.

https://doi.org/10.1371/journal.pone.0252984.g001

Patient selection

The study cohort included consecutive COVID-19 patients ≥18 years old who were hospitalized at KFMC between May 1st and September 30, 2020. Confirmation of infection with SARS-CoV-2 was made by nasopharyngeal swab polymerase chain reaction (PCR). These patients should have also received either triple combination therapy or FPV. We included patients hospitalized with mild, moderate, or severe disease as per the National Institute of Health (NIH) classification [15]. Critical illness was considered as one of the study endpoints. We did not include pre-hospitalization ambulatory management data as these were not available to us. Most patients received only supportive over the counter medications before hospital admission while a few received hydroxychloroquine in the Ministry of Health Primary Care Centers.

Drug therapy

KFMC COVID-19 management protocol for the treatment of COVID-19 infection was followed for treatment options (S1 Table). This treatment protocol was prepared by KFMC COVID-19 scientific taskforce, a multidisciplinary team of infectious diseases, intensive care physicians, and clinical pharmacists. Our treatment protocol included: a 14-day course of LPV/r 400mg/100 mg twice daily, RBV 400 mg twice daily and zero to three doses of received recombinant IFN beta-1b (Betaferon, Bayer) as a subcutaneous injection (at a dose of 0.25 mg [8 million IU] in 1 ml of solvent) on alternate days 1, 3 and 5 (depending on the number of days between admission and symptoms onset) [11], or a 7 to 10-days course of FPV regimen 1800 mg/dose twice daily on day one, followed by 800 mg/dose twice daily for 7–10 days. Interferon-based therapy was not recommended beyond 7 days of symptoms onset. Remdesivir was not available in Saudi Arabia. Criteria for steroids use (methylprednisolone 0.5–1 mg/kg/day divided in two doses for five days) or dexamethasone 6 mg orally (once daily or equivalent intravenous dose for 10 days) included for moderate COVID-19 patients who are at need for supplemental oxygen ≥ 4 L or increasing oxygen requirements from the baseline and for the mechanically ventilated severe COVID-19 patients with acute respiratory distress syndrome (ARDS). Tocilizumab 8mg/kg was considered in patients with cytokine release syndrome (CRS), rapidly worsening respiratory symptoms/signs, and absence of systemic bacterial or fungal coinfection in addition to 2 or more of the following criteria: a) ferritin >300 ug/L doubled within 24 hours, b) ferritin >600 ug/L at presentation, c) lactic acid dehydrogenase (LDH) >250, d) increased D-dimer (>1 mcg/mL), e) C-reactive protein (CRP) > 70 mg/L. Interlukin-6 (IL-6) assay was not available. All patients received standard of care management in addition to the previous therapeutic options.

Data collection

Patients were evaluated daily by infectious disease physicians and data were documented prospectively in the daily assessment form (S1 Table). Additional data were retrieved from patients’ electronic medical records. To assess the safety profile of IFN-based regimen, serial levels of hemoglobin, platelet count, alanine aminotransferase (ALT), and bilirubin were evaluated. The study outcomes were ascertained at 28 days after admission irrespective of hospital discharge. For patients who were discharged before 28 days, the research team called patients or their families more than once: 1) to ask about side effect profiles if they were still receiving the treatment regimen, and 2) to ascertain vital status and re-hospitalizations.

Outcomes

The study primary outcome was all-cause mortality, and the secondary outcomes were the need of mechanical ventilation or intensive care unit admission at day 28 after hospital admission. We have also evaluated the following outcomes: a) National Early Warning Score (NEWS-2) at day 1, 3 and 7 of hospitalization, b) use of steroids, c) use of tocilizumab within 28 days. Safety related endpoints included: patient reports of adverse events, and levels of hemoglobin, platelet count, alanine aminotransferase (ALT), and bilirubin at day 1, 3 and 7 of hospitalization. The NEWS-2 is an aggregate scoring system predicting diseases severity and mortality [16].

Statistical analysis

Chai-square or Fisher exact tests for categorical variables and Student t test or Mann-Whitney U test for continuous variables (where appropriate) were used to compare baseline clinical characteristics and interventions of patients who received triple therapy to those who did not.

For the primary outcome of 28-day mortality and secondary outcomes of mechanical ventilation or intensive care unit admission, a sequential series of two Cox proportional hazard models were developed. Time zero was considered to be the hospital admission date in all survival analyses. Model 1 was developed by adding patient baseline variables at admission (age, gender, body mass index, and SpO2 value) and Model 2 was developed by adding patient variables related to COVID-19 severity (serum CRP, ferritin, D-Dimer, and bilirubin levels, WBC), oxygen needs and use of systemic corticosteroids during hospital stay [17] (S2–S4 Tables). The presence of collinearity among variables was examined by the evaluation of variance inflation factors. Model improvement through addition of variables were assessed using measures of discrimination and goodness of fit [18]. Concordance statistics (C statistics) is a measure of discrimination which refers to the ability of a model to distinguish between two groups of outcomes [19]. Overall model fit for sequential Cox proportional hazard models was measured using the Akaike Information Criterion (AIC), which takes into account both model statistical goodness of fit (-2log-likelihood) and the number of estimated variables used to develop the model by imposing a penalty for increasing the number of variables in the model [20–22]. Higher values for C statistic and lower values for AIC indicate better models. Moreover, triple IFN-based therapy was considered as a time-varying covariate to avoid “immortal time bias” or “survivor selection bias”, which occurs because patients who live longer are more likely to receive treatment than those who die early [23–25]. In this study since time from symptoms onset to start of treatment was different for individual patients, triple IFN-based therapy was considered as a time-varying covariate in the model. The hazard ratio with 95% CIs from the best Cox regression model (model 2) was used to estimate the mortality ratio of IFN based therapy vs. FPV therapy at 28-day follow up. Kaplan–Meier survival curves were constructed to show cumulative survival over the 28-day period.

We also compared NEWS-2 score at day 1, 3 and 7 of hospitalization, length of hospital stay, and the use of supportive treatments for COVID-19 such steroids and tocilizumab between IFN based therapy vs. FPV therapy groups. For evaluating NEWS-2 score between these two treatment groups at the given days, we have used generalized linear mixed models which included fixed effect of treatment and random effect of age, male sex, body mass index, and time from start of symptoms onset to start of treatment, days.

Furthermore, for assessing the use of supportive treatments between IFN based therapy vs. FPV therapy groups logistic regression models have been developed and adjusted for both patient baseline variables at admission and patient COVID-19 related severity variables during hospital stay.

All tests were 2 tailed and a P value of less than 0.05 was considered statistically significant. Statistical analysis was performed using SPSS (version 26.0), R software (version 3.6.1) and PRISM (version 8). A file consisting of all patient’s parameters used in the analysis is provided in S1 File.

Results

Baseline clinical characteristics

Of the 243 COVID-19 patients, 21 patients were excluded from the study because they received dual LPV/r and RBV without IFN as they presented one week after symptoms onset. 222 patients were included in the final analysis, of whom 68 (28%) received IFN-based therapy. No statistically significant differences in age, sex, body mass index and comorbidities were observed among the 2 groups. Patients who treated with IFN-based therapy were more likely to be admitted with severe disease (45% vs 32%; P = 0.067) or mild disease (10% vs 22%; P = 0.04), with more fever and gastrointestinal symptoms (Table 1). Time from symptoms onset to hospitalization was 4 days (3–5.5 days) for the IFN-based therapy group vs. 5 days (3–7 days) for the FPV group, P = 0.022. Antiviral therapy was commenced at a median of 5 days (3–6 days) from symptoms onset in the IFN-based therapy group vs. 6 days (4–7 days) for the FPV group, P <0.0001. The distribution of triple therapy vs. FPV over time (May-June 2020) confirmed that allocation of patients to the 2 treatment groups was due to treatment protocol changes and therefore the study was less susceptible to selection bias or confounding by indication (Fig 1).

[Figure omitted. See PDF.]

Table 1. Baseline clinical characteristics of the study population.

https://doi.org/10.1371/journal.pone.0252984.t001

Efficacy outcomes

Favipiravir was associated with higher mortality as compared to those who received IFN-based therapy (Fig 2). IFN-based therapy was associated with a lower 28-day mortality (6 (9%) vs. 18 (12%)), adjusted hazard ratio [aHR] (95% Cl) = 0.27 (0.08–0.88). Of note, all the death in IFN-based and the majority in FPV (15 out of 18 death, 83%) occurred in severe COVID-19 patients (Table 2). No statistically significant difference in ICU admission or the need for mechanical ventilation between the 2 groups was observed (Table 2). IFN-based therapy group had lower NEWS2 score at day 3 and 7 as compared to FPV (Table 3). There was no difference in hospitalization duration between the 2 groups 9 (7–14) days vs. 9 (7–13) days, P = 0.732. After controlling for between group differences, IFN-based therapy group required less use of systemic corticosteroids (57%) during hospitalization as compared to FPV (77%), (P = 0.005, logistic regression) and Tocilizumab (4%) vs. (7%), (P = 0.170, logistic regression) (Table 3 and Fig 3).

[Figure omitted. See PDF.]

Fig 2. Kaplan–Meier curves for survival at 28 days follow up.

Cox proportional model has been adjusted for both patient baseline variables at admission (patients’ age, male sex, body mass index, SpO2) and patient COVID-19 related severity variables during hospital stay (serum CRP, ferritin, and D-Dimer, and bilirubin levels, WBC, oxygen needs and systemic use of dexamethasone).

https://doi.org/10.1371/journal.pone.0252984.g002

[Figure omitted. See PDF.]

Fig 3. Comparison of proportions of patients requiring corticosteroids or tocilizumab during their treatment course in the interferon-based triple therapy vs. favipiravir groups*.

*The use of supportive treatments such as tocilizumab and systemic corticosteroids between IFN-based therapy vs. FPV therapy groups was evaluated by logistic regression models adjusted for both patient baseline variables at admission (patients’ age, male sex, body mass index, SpO2) and patient COVID-19 related severity variables during hospital stay (serum CRP, ferritin, and D-Dimer, and bilirubin levels, WBC, and oxygen needs).

https://doi.org/10.1371/journal.pone.0252984.g003

[Figure omitted. See PDF.]

Table 2. Primary and secondary outcomes.

https://doi.org/10.1371/journal.pone.0252984.t002

[Figure omitted. See PDF.]

Table 3. Temporal outcomes of interferon-based triple therapy vs. favipiravir.

https://doi.org/10.1371/journal.pone.0252984.t003

Safety endpoints

No differences between the 2 groups over time in hemoglobin, platelet count, or, ALT was found (S5 Table). There was a statistically significant, but clinically non-significant, increase in bilirubin level in the IFN-based therapy group. In addition, patients in the IFN-based therapy were more likely to have nausea and diarrhea as compared to FPV group (13%) vs. (3%), P = 0.013 and (18%) vs. (3%), P<0.0001, respectively.

Discussion

Findings

In this cohort study of patients hospitalized with non-critical COVID-19, we observed that: First, IFN-based triple therapy (IFN-β-1b plus RBV, plus LPV/r) was associated with lower 28-day mortality as compared to FPV; aHR 0.27, 95% CI (0.08–0.88). Second, IFN-based triple therapy treated patients had lower (NEWS2) score, currently recommended in the United Kingdom for risk stratification of COVID-19 outcomes, at days 3 and 7 of follow-up. Third, IFN-based triple therapy was associated with less need for systemic corticosteroids as an immunomodulatory therapy. Fourth, a clinically significant higher risk of serious adverse events was not observed with IFN-based triple therapy.

Mechanisms

Type I IFN-signaling is essential for antiviral innate immunity, and plays a critical role in preventing the progression of viral infection and development of severe disease [26, 27]. In fact, Yuan et al. examined the antiviral activity of IFNs (IFN β-1a, IFN β-1b, pegylated IFN α-2a and IFN γ-1b) and other antivirals (lopinavir and remdesivir) using the plaque reduction assay. Among IFNs, IFN β-1b (Betaferon) was the most potent anti-SARS-CoV-2 with the lowest EC50 (31.2 IU/mL) and the highest selectivity index (>1602.6). The EC50 values for remdesivir and lopinavir were 1.04 and 11.6 μM, respectively [28].

Interestingly, gene variants affecting Type I IFN production and/or signaling have been shown to predispose patients to the development of severe COVID19 disease [29]. It is suggested that low levels of type I IFN, especially early on during infection, may result in an improper control of viral replication leading to tissue damage and exaggerated immune responses [30, 31]. Unlike SARS-CoV and MERS-CoV diseases where viral load peaks around days 7–10 after symptoms onset, viral load of SARS-CoV-2 reach its peaks at the time of symptom onset, indicating uncontrolled viral replication [32]. Therefore, early initiation of antiviral therapy is essential in COVID-19.

Comparison to other studies

To date, there is no comparative study of IFN-based therapy vs. FPV for COVID-19. However, the therapeutic role of type I IFN for coronavirus infections has been investigated using both preclinical and clinical approaches. For example, an Italian experimental preclinical study has investigated the efficacy of IFN-β-1a controlling SARS-CoV-2 replication in Vero E6 cells. High concentrations of IFN-β-1a (5000 to 50 IU/mL) prevented SARS-CoV-2 replication in vero E6 cells while lower concentrations (0.05 and 0.01 IU/mL) had no effect on virus growth [33].

SARS-CoV expresses three IFN antagonistic proteins, open reading frame (ORF) 3b, ORF6, and N proteins that hinder different aspects of the interferon response. These proteins inhibit both IFN production and signaling [34]. Sallard et al., hypothesized that SARS-CoV-2 Orf6 and Orf3b proteins may have lost their anti-IFN functions which may elucidate the substantial sensitivity of SARS-CoV-2 to IFN-α treatment compared to other coronaviruses [35].

Nevertheless, there are few RCTs that examined the efficacy of IFN-based therapy vs. placebo or standard of care. Hung et al. performed the first prospective multicenter, randomized, phase 2 clinical trial on 127 hospitalized adult patients with mild to moderate COVID-19. They compared early initiation of 14-day combination of LPV/r, RBV, and three doses of IFN-β-1b (combination group) to 14 days of LPV/r (control group). The combination group had a significantly shorter median time to negative SARS-CoV-2 RT-PCR (7 days) compared to the control group (12 days); HR 4·37 [95% CI 1·86–10·24], p = 0·0010); and a significantly shorter time (4 days) to complete symptoms resolution, suppression of IL-6 levels, and a shorter hospital stay. However, the triple therapy group at baseline had significantly lower NEWS2 score than the control on day 1–7 which may have contributed to a favorable outcome in triple therapy cohort [11]. In another RCT of 92 patients, 42 patients received IFN β-1a in addition to the national protocol medications (hydroxychloroquine plus LPV/r or atazanavir-ritonavir). IFN-β-1a (44-μg/ml (12 million IU/ml)) was injected subcutaneously three times a week for two consecutive weeks. The control group of 39 patients were treated by the national protocol medications only. On day 14, 66.7% patients in the IFN group and 43.6% of patients in the control group were discharged (odds ratio [OR], 2.5; 95% confidence interval [CI], 1.05–6.37). A statistically significant lower mortality in the IFN than the control group (19% versus 43.6%) at day 28. Early administration of IFN significantly reduced mortality (OR, 13.5; 95% CI, 1.5–118). However, late administration did not reveal significant effects (OR, 2.1; 95% CI, 0.48–9.6) [36].

More recently, data from the WHO SOLIDARITY trial showed different findings [8, 9]. The SOLIDARITY RCT is an international, open-label, adaptive randomized trial of hospitalized COVID-19 patients. The trial included an IFN treatment arm. The regimen for IFN (mainly subcutaneous) was three doses (44 μg/dose) over a period of 6- days. The trial was conducted at 405 hospitals in 30 countries and 2063 were allocated to receive IFN (including 651 to IFN plus LPV/r). Death occurred in 243 of 2050 patients receiving IFN and in 216 of 2050 in the control group (risk ratio, 1.16; 95% CI, 0.96–1.39; P = 0.11). Nevertheless, subgroup analyses suggested that IFN-based therapy was associated with higher mortality in ventilated vs. non ventilated patients and in patients started on treatment >2 days after admission as compared to earlier initiation of therapy [9].

On the other hand, FPV has not been extensively examined in RCTs. FPV is a purine nucleoside analogue and a virus RNA-dependent RNA polymerase inhibitor that was originally approved in 2014 by the Japan Pharmaceuticals and Medical Devices Agency for influenza A virus infection treatment. It works as a chain terminator at the site of incorporation of the viral RNA thus decreasing the viral load. It is not toxic to mammalian cells because it does not inhibit their RNA or DNA synthesis [37].

In a small open-label non-randomized before-and-after study by Cai et al., clinical outcome of 80 adult patients with non-severe COVID-19 was evaluated by comparing 2 groups: 35 in FPV arm versus 45 patients in the LPV/r arm. Both groups received aerosol inhalation of IFN-α 1b twice daily. Primary end points were time to viral clearance and improvement in chest CT by day 14. Patients on FPV displayed a shorter time to viral clearance (median of 4 days, IQR: 2.5–9) than LPV/r arm (median of 11 days, IQR: 8–133) (P < 0.001) [9].

Despite being included in multiple national treatment protocols for COVID-19, the evidence supporting FPV use remains weak. A recent systematic review by the EUnetHTA Rolling Collaborative Review (RCR11) Authoring Team [14] concluded that the current evidence base does not support the use of FPV as monotherapy or combination therapy for COVID-19. In another recently updated WHO living systematic review and network meta-analysis, FPV was found to have no effect on mortality with an absolute risk reduction of -41 per 10000 (-113 to 207). The 95% credible interval included no effect, and certainty of evidence was rated as very low [38].

Strengths and limitations

Our study has multiple strengths. First, to our knowledge, this is the first comparative study of IFN-based therapy vs. FPV in COVID-19. Second, although observational in nature, our study is less susceptible to treatment selection bias given that the allocation to treatment groups was based on drug availability and national treatment protocols which minimizes the risk of confounding by indication. Third, our analysis accounted for immortal time bias. Not considering the immortal time in the design or analysis of observational studies could lead to inflated treatments’ effect estimates. Based on data from at least one study in COVID-19 [39] and another influenza study [40], mortality relative risk increased by up to 60% when not considered treatment as a time-dependent variable in the Cox regression analysis [38]. However, our study has several limitations. First, our study was not an RCT and therefore we cannot completely rule out the effect of unmeasured or residual confounding or treatment selection bias. Second, the low number of events limited our ability to adjust for many potential confounders in the Cox model. Third, because our protocol did not allow the use of IFN-based therapy 7 days after symptoms onset, we could not compare the effect of early vs. late IFN effect on outcomes. Fourth, our study is a single center experience. Fifth, although, prehospital treatment might affect patients’ outcomes [41], we believe that this it is unlikely to affect our findings as in this study the majority of patients received either no prehospital therapy due to unavailability of effective antiviral therapy for COVID-19 in the outpatient setting at the date of the study, or very few received hydroxychloroquine in the outpatient setting. However, multiple RCTs have failed to show any benefit of hydroxychloroquine on all outcomes [42]. Moreover, If any prehospital effect is present, it should cause a random error rather than bias. Additionally, we have considered treatment with IFN- based therapy and FPV as time-dependent variables and adjusted for time since symptoms onset to address any raised survivor bias [23, 25]. Finally, patients with respiratory failure requiring mechanical ventilation, ARDS, and patients with CRS were excluded from our study, which limits the generalizability of our findings to critically ill patients.

Conclusions

In this quasi-experimental comparative analysis of hospitalized patients with non-critical COVID-19, we observed that early IFN-based triple therapy was associated with better outcomes as compared to FPV with a statistically significant reduction in mortality at 28 days and a reduced need for adjunctive systemic corticosteroids. Future randomized controlled trials are needed to compare these 2 treatment regimens.

Supporting information

S1 Table. COVID-19 patient assessment form.

https://doi.org/10.1371/journal.pone.0252984.s001

(PDF)

S2 Table. Primary outcome of mortality at 28 days.

https://doi.org/10.1371/journal.pone.0252984.s002

(PDF)

S3 Table. Secondary outcome of mechanical ventilation.

https://doi.org/10.1371/journal.pone.0252984.s003

(PDF)

S4 Table. Secondary outcome of intensive care unit admission.

https://doi.org/10.1371/journal.pone.0252984.s004

(PDF)

S5 Table. Adverse events of interferon-based triple therapy vs. favipiravir.

https://doi.org/10.1371/journal.pone.0252984.s005

(PDF)

S1 File. Study raw data.

https://doi.org/10.1371/journal.pone.0252984.s006

(SAV)

Acknowledgments

We would like to thank the staff at the Research Center and members of the COVID-19 scientific taskforce at King Fahad Medical City.

Citation: A. Malhani A, A. Enani M, Saheb Sharif-Askari F, R. Alghareeb M, T. Bin-Brikan R, A. AlShahrani S, et al. (2021) Combination of (interferon beta-1b, lopinavir/ritonavir and ribavirin) versus favipiravir in hospitalized patients with non-critical COVID-19: A cohort study. PLoS ONE 16(6): e0252984. https://doi.org/10.1371/journal.pone.0252984

References

1. World Health Organization. https://www.who.int/publications/m/item/weekly-operational-update-on-covid-19—21-december-2020. Access date: 20/12/2020.

2. Bhimraj A, Morgan RL, Shumaker AH, Lavergne V, Baden L, Cheng VC-C, et al. Infectious diseases Society of America guidelines on the treatment and management of patients with COVID-19. Clinical Infectious Diseases.

3. Schoggins JW, Rice CM. Interferon-stimulated genes and their antiviral effector functions. Current opinion in virology. 2011;1(6):519–25. pmid:22328912

4. Cinatl J Jr, Michaelis M, Scholz M, Doerr HW. Role of interferons in the treatment of severe acute respiratory syndrome. Expert opinion on biological therapy. 2004;4(6):827–36. pmid:15174965

5. Taylor MW. Viruses and man: A history of interactions: Springer; 2014.

6. Cao B, Wang Y, Wen D, Liu W, Wang J, Fan G, et al. A Trial of Lopinavir–Ritonavir in Adults Hospitalized with Severe Covid-19. New England Journal of Medicine. 2020;382(19):1787–99. pmid:32187464

7. Horby PW, Mafham M, Bell JL, Linsell L, Staplin N, Emberson J, et al. Lopinavir–ritonavir in patients admitted to hospital with COVID-19 (RECOVERY): a randomised, controlled, open-label, platform trial. The Lancet. 2020;396(10259):1345–52. pmid:33031764

8. Perveen RA, Nasir M, Talha KA, Selina F, Islam MA. Systematic review on current antiviral therapy in COVID-19 pandemic. The Medical Journal of Malaysia. 2020;75(6):710–6. pmid:33219182

9. Repurposed Antiviral Drugs for Covid-19—Interim WHO Solidarity Trial Results. New England Journal of Medicine. 2020. pmid:33264556

10. Dong L, Hu S, Gao J. Discovering drugs to treat coronavirus disease 2019 (COVID-19). Drug discoveries & therapeutics. 2020;14(1):58–60.

11. Hung IF-N, Lung K-C, Tso EY-K, Liu R, Chung TW-H, Chu M-Y, et al. Triple combination of interferon beta-1b, lopinavir–ritonavir, and ribavirin in the treatment of patients admitted to hospital with COVID-19: an open-label, randomised, phase 2 trial. The Lancet. 2020;395(10238):1695–704.

12. Joshi S, Parkar J, Ansari A, Vora A, Talwar D, Tiwaskar M, et al. Role of favipiravir in the treatment of COVID-19. International Journal of Infectious Diseases. 2020. pmid:33130203

13. Agrawal U, Raju R, Udwadia ZF. Favipiravir: A new and emerging antiviral option in COVID-19. Medical Journal Armed Forces India. 2020. pmid:32895599

14. EUnetHTA Rolling Collaborative Review (RCR11) Authoring Team. Favipiravir for the treatment of COVID-19. Diemen (The Netherlands): EUnetHTA; 2020 49 pages Report No: RCR11 https//www.eunethta.eu Access date: 9/12/2020.

15. Clinical Spectrum of SARS-CoV-2 Infection. https://www.covid19treatmentguidelines.nih.gov/overview/clinical-spectrum/. Access date: 12/12/2020.

16. Myrstad M, Ihle-Hansen H, Tveita AA, Andersen EL, Nygård S, Tveit A, et al. National Early Warning Score 2 (NEWS2) on admission predicts severe disease and in-hospital mortality from Covid-19–a prospective cohort study. Scandinavian journal of trauma, resuscitation and emergency medicine. 2020;28(1):1–8. pmid:31900203

17. Izcovich A, Ragusa MA, Tortosa F, Lavena Marzio MA, Agnoletti C, Bengolea A, et al. Prognostic factors for severity and mortality in patients infected with COVID-19: A systematic review. PloS one. 2020;15(11):e0241955. pmid:33201896

18. Steyerberg EW, Eijkemans MJC, Harrell FE Jr, Habbema JDF. Prognostic modelling with logistic regression analysis: a comparison of selection and estimation methods in small data sets. Statistics in medicine. 2000;19(8):1059–79. pmid:10790680

19. Pencina MJ, D’Agostino RB. Overall C as a measure of discrimination in survival analysis: model specific population value and confidence interval estimation. Statistics in medicine. 2004;23(13):2109–23. pmid:15211606

20. Steyerberg EW. Clinical prediction models: Springer; 2019.

21. Tangri N, Stevens LA, Griffith J, Tighiouart H, Djurdjev O, Naimark D, et al. A predictive model for progression of chronic kidney disease to kidney failure. Jama. 2011;305(15):1553–9. pmid:21482743

22. Sharif-Askari FS, Sulaiman SAS, Sharif-Askari NS, Hussain AAS. Development of an adverse drug reaction risk assessment score among hospitalized patients with chronic kidney disease. PLoS One. 2014;9(4):e95991. pmid:24755778

23. Tleyjeh IM, Ghomrawi HMK, Steckelberg JM, Montori VM, Hoskin TL, Enders F, et al. Conclusion about the association between valve surgery and mortality in an infective endocarditis cohort changed after adjusting for survivor bias. Journal of clinical epidemiology. 2010;63(2):130–5. pmid:20122499

24. Sy RW, Bannon PG, Bayfield MS, Brown C, Kritharides L. Survivor treatment selection bias and outcomes research: a case study of surgery in infective endocarditis. Circulation: Cardiovascular Quality and Outcomes. 2009;2(5):469–74. pmid:20031879

25. Tleyjeh IM, Ghomrawi HM, Steckelberg JM, Hoskin TL, Mirzoyev Z, Anavekar NS, et al. The impact of valve surgery on 6-month mortality in left-sided infective endocarditis. Circulation. 2007;115(13):1721–8. pmid:17372170

26. McCoy K, Peterson A, Tian Y, Sang Y. Immunogenetic association underlying severe COVID-19. Vaccines. 2020;8(4):700. pmid:33233531

27. Monk PD, Marsden RJ, Tear VJ, Brookes J, Batten TN, Mankowski M, et al. Safety and efficacy of inhaled nebulised interferon beta-1a (SNG001) for treatment of SARS-CoV-2 infection: a randomised, double-blind, placebo-controlled, phase 2 trial. The Lancet Respiratory Medicine. 2020. pmid:33189161

28. Yuan S, Chan CC-Y, Chik KK-H, Tsang JO-L, Liang R, Cao J, et al. Broad-Spectrum Host-Based Antivirals Targeting the Interferon and Lipogenesis Pathways as Potential Treatment Options for the Pandemic Coronavirus Disease 2019 (COVID-19). Viruses. 2020;12(6):628.

29. Zhang Q, Bastard P, Liu Z, Le Pen J, Moncada-Velez M, Chen J, et al. Inborn errors of type I IFN immunity in patients with life-threatening COVID-19. Science. 2020;370(6515).

30. Meffre E, Iwasaki A. Interferon deficiency can lead to severe COVID. Nature Publishing Group; 2020. pmid:33139913

31. Pairo-Castineira E, Clohisey S, Klaric L, Bretherick AD, Rawlik K, Pasko D, et al. Genetic mechanisms of critical illness in Covid-19. Nature. 2020:1-. pmid:33307546

32. Cevik M, Tate M, Lloyd O, Maraolo AE, Schafers J, Ho A. SARS-CoV-2, SARS-CoV, and MERS-CoV viral load dynamics, duration of viral shedding, and infectiousness: a systematic review and meta-analysis. The Lancet Microbe. 2020.

33. Clementi N, Ferrarese R, Criscuolo E, Diotti RA, Castelli M, Scagnolari C, et al. Interferon-β-1a inhibition of severe acute respiratory syndrome–coronavirus 2 in vitro when administered after virus infection. The Journal of infectious diseases. 2020;222(5):722–5. pmid:32559285

34. Kopecky-Bromberg SA, Martínez-Sobrido L, Frieman M, Baric RA, Palese P. Severe acute respiratory syndrome coronavirus open reading frame (ORF) 3b, ORF 6, and nucleocapsid proteins function as interferon antagonists. Journal of virology. 2007;81(2):548–57. pmid:17108024

35. Sallard E, Lescure F-X, Yazdanpanah Y, Mentre F, Peiffer-Smadja N. Type 1 interferons as a potential treatment against COVID-19. Antiviral research. 2020;178:104791. pmid:32275914

36. Davoudi-Monfared E, Rahmani H, Khalili H, Hajiabdolbaghi M, Salehi M, Abbasian L, et al. A randomized clinical trial of the efficacy and safety of interferon β-1a in treatment of severe COVID-19. Antimicrobial agents and chemotherapy. 2020;64(9). pmid:32661006

37. Cai Q, Yang M, Liu D, Chen J, Shu D, Xia J, et al. Experimental treatment with favipiravir for COVID-19: an open-label control study. Engineering. 2020;6(10):1192–8. pmid:32346491

38. Siemieniuk RA, Bartoszko JJ, Ge L, Zeraatkar D, Izcovich A, Kum E, et al. Drug treatments for covid-19: living systematic review and network meta-analysis. Bmj. 2020;370. pmid:32732190

39. Wu J, Huang J, Zhu G, Liu Y, Xiao H, Zhou Q, et al. Systemic corticosteroids and mortality in severe and critical COVID-19 patients in Wuhan, China. The Journal of Clinical Endocrinology & Metabolism. 2020;105(12):dgaa627. pmid:32880390

40. Wolkewitz M, Schumacher M. Survival biases lead to flawed conclusions in observational treatment studies of influenza patients. Journal of clinical epidemiology. 2017;84:121–9. pmid:28188897

41. Procter B, Ross C, Pickard V, Smith E, Hanson C, McCullough PA. Early ambulatory multidrug therapy reduces hospitalization and death in high-risk patients with SARS-CoV-2 (COVID-19). Authorea Preprints. 2021.

42. Kashour Z, Kashour T, Gerberi D, Tleyjeh IM. Mortality, viral clearance, and other clinical outcomes of hydroxychloroquine in COVID‐19 Patients: A Systematic Review and Meta‐Analysis of Randomized Controlled Trials. Clinical and Translational Science. 2021.