Comparison of COVID-19 Preprint and Peer-Reviewed Versions of Studies on Therapies for Critically Ill Patients

PURPOSE

Significant increases in the volume of preprint articles due to the COVID-19 pandemic, we examined the reliability of preprint articles compared to their peer-reviewed publications.

MATERIALS AND METHODS

Preprint articles evaluating experimental studies of select treatment options (anticoagulation, dexamethasone, hydroxychloroquine, remdesivir, and tocilizumab) for COVID-19 in the critically ill, available in a peer-reviewed publication were screened for inclusion within Altmetric (n = 2040). A total of 40 articles met inclusion criteria, with 21 being randomly selected for evaluation. The primary outcome of this evaluation was a change in a study's reported primary outcome or statistical significance between preprint and peer-reviewed articles. Secondary outcomes included changes in primary/secondary outcome effect size and change in study conclusion.

RESULTS

One article (4.8%, 95% CI 0.12%-23.8%) had a change in the primary outcome. Seven articles (33.3%, 95% CI 14.6%-57.0%) had a change in the primary outcome's effect measure. Five studies (23.8%, 95% CI 8.2%-47.2%) had changes in statistical significance of at least one secondary outcome. Four studies (19.0%, 95% CI 5.4%-41.9%) had a change in study conclusion.

CONCLUSIONS

In preprint articles of COVID-19 treatments, the provided primary outcome is generally reliable, while interpretation of secondary outcomes should be made with caution, while awaiting completion of the peer-review process.

Corporate Moral Responsibility, Distributive Justice, the Common Good, and Catholic Social Teaching: The Case of Gilead Sciences and Remdesivir

Applying the moral principles of Catholic social teaching's (CST) on capitalism, distributive justice, private ownership, the common good, and the role of the state in the economy as the overall theoretical framework and utilizing secondary data, media reports, and scientific literature, this article explores the corporate moral responsibility of the top drug makers in the ownership and pricing of their essential medicines and COVID-19 vaccines. Specifically, it presents the case of the Gilead Sciences' business strategies and overpricing of Remdesivir drug to illustrate how predatory capitalism undermines the moral responsibility of drug makers and CST's moral principle on the common good in today's pandemic. Distributive justice requires that the publicly funded and developed medicines and vaccines should be priced and distributed fairly to promote the common good and prevent the public from "paying twice" for these essential medicines. Given the public character of these medicines and the demands of social justice, the price of Remdesivir and other essential medicines of Gilead Sciences and Big Pharma for COVID-19 could have been lower than what was officially announced. Ultimately, these medicines could have been made global public health goods in accordance with CST's doctrines on distributive justice, the common good, and the social dimension of private ownership.

Remdesivir-Loaded Nanoliposomes Stabilized by Chitosan/Hyaluronic Acid Film with a Potential Application in the Treatment of Coronavirus Infection

An object of the present study was the development of liposomes loaded with the medicine Veklury® (remdesivir) stabilized by electrostatic adsorption of polysaccharide film formed from chitosans with different physicochemical characteristics and hyaluronic acid. The functionalization of the structures was achieved through the inclusion of an aptamer (oligonucleotide sequence) with specific affinity to the spike protein of the human coronavirus HCoV-OC43. The hydrodynamic size, electrokinetic potential and stability of the structures were evaluated at each step in the procedure. The encapsulation efficiency and loaded amount of remdesivir (99% and 299 µg/mL) were estimated by UV-vis spectroscopy. Our investigations showed manifestation of promising tendencies for prolonged periods of the drug release and increased effectiveness of its antiviral action. Among all studied versions of the delivery system, the most distinguished and suitable in a model coronavirus therapy are the liposomes formed from chitosan oligosaccharides. The cytotoxicity of the liposomes was determined against the HCT-8 cell line. A cytopathic effect inhibition test was used for the assessment of the antiviral activity of the compounds. The virucidal activity and the effect on the viral adsorption of the samples were reported by the end-point dilution method, and the alteration in viral titer was determined as Δlgs compared to untreated controls. The redox-modulating properties of the nanoparticles were studied in vitro in certain/several/a few chemical model systems. Our investigations showed a manifestation of promising tendencies for a prolonged effect of the drug release and increased effectiveness of its antiviral action.

Vaccination and Antiviral Treatment Reduce the Time to Negative SARS-CoV-2 Swab: A Real-Life Study

Clinical trials demonstrated the role of vaccines and antiviral treatments against SARS-CoV-2 in reducing the likelihood of disease progression and death. However, there are limited data available regarding the time to negativity of people who received these treatments. Further, several comorbidities and risk factors might affect the impact of vaccines and antiviral treatments. To this end, we aimed to evaluate and disentangle the impact of anti-SARS-CoV-2 treatments and that of underlying clinical factors associated with a shortened length of SARS-CoV-2 infection. Hence, we recorded the timeframe of positive nasopharyngeal swab in people infected while being hospitalized for reasons other than SARS-CoV-2 infection. All patients who died or were discharged with a positive swab were excluded from the study. A total of 175 patients were included in this study. Clinical conditions encompass malignancies, immunological disorders, cardiovascular, metabolic, neurodegenerative, and chronic kidney disease. Most of the participants (91.4%) were vaccinated before admission to the hospital, and 65.1% received antiviral treatment within three days after the symptom's onset. Unvaccinated patients had a longer median time to negativity than people who received at least two doses of vaccine (18 vs. 10 days). Concerning the clinical conditions of all patients, multivariate analysis highlighted a lower probability of 14-day conversion of antigenic test positivity in patients with hematological malignancy, including those vaccinated and those exposed to antiviral therapies. In conclusion, our data showed that prompt administration of antiviral treatments accelerates the clearance of SARS-CoV-2. Further, in the elderly patients under study, previous vaccination and antiviral treatment synergize to reduce time to negativity. This translates into a shorter hospitalization time and a lower risk of transmission through patients and connected healthcare workers in a hospital ward setting, with considerable improvement in cost-effective care management.

Chemoprophylactic Assessment of Combined Intranasal SARS-CoV-2 Polymerase and Exonuclease Inhibition in Syrian Golden Hamsters

Pibrentasvir (PIB) has been demonstrated to block exonuclease activity of the SARS-CoV-2 polymerase, protecting favipiravir (FVP) and remdesivir (RDV) from post-incorporation excision and eliciting antiviral synergy in vitro. The present study investigated the chemoprophylactic efficacy of PIB, FVP, RDV, FVP with PIB, or RDV with PIB dosed intranasally twice a day, using a Syrian golden hamster contact transmission model. Compared to the saline control, viral RNA levels were significantly lower in throat swabs in FVP (day 7), RDV (day 3, 5, 7), and RDV+PIB (day 3, 5) treatment groups. Similarly, findings were evident for nasal turbinate after PIB and RDV treatment, and lungs after PIB, FVP, and FVP+PIB treatment at day 7. Lung viral RNA levels after RDV and RDV+PIB treatment were only detectable in two animals per group, but the overall difference was not statistically significant. In situ examination of the lungs confirmed SARS-CoV-2 infection in all animals, except for one in each of the RDV and RDV+PIB treatment groups, which tested negative in all virus detection approaches. Overall, prevention of transmission was observed in most animals treated with RDV, while other agents reduced the viral load following contact transmission. No benefit of combining FVP or RDV with PIB was observed.

Retrospective Analysis of a Real-Life Use of Tixagevimab-Cilgavimab plus SARS-CoV-2 Antivirals for Treatment of COVID-19

Tixagevimab-cilgavimab is effective for the treatment of early COVID-19 in outpatients with risk factors for progression to severe illness, as well as for primary prevention and post-exposure prophylaxis. We aimed to retrospectively evaluate the hospital stay (expressed in days), prognosis, and negativity rate for COVID-19 in patients after treatment with tixagevimab-cilgavimab. We enrolled 42 patients who were nasal swab-positive for SARS-CoV-2 (antigenic and molecular)-both vaccinated and not vaccinated for COVID-19-hospitalized at the first division of the Cotugno Hospital in Naples who had received a single intramuscular dose of tixagevimab-cilgavimab (300 mg/300 mg). All patient candidates for tixagevimab-cilgavimab had immunocompromised immune systems either due to chronic degenerative disorders (Group A: 27 patients) or oncohematological diseases (Group B: 15 patients). Patients enrolled in group A came under our observation after 10 days of clinical symptoms and 5 days after testing positivite for COVID-19, unlike the other patients enrolled in the study. The mean stay in hospital for the patients in Group A was 21 ± 5 days vs. 25 ± 5 days in Group B. Twenty patients tested negative after a median hospitalization stay of 16 days (IQR: 18-15.25); of them, five (25%) patients belonged to group B. Therefore, patients with active hematological malignancy had a lower negativization rate when treated 10 days after the onset of clinical symptoms and five days after their first COVID-19 positive nasal swab.

Use of Remdesivir in Patients Hospitalized for COVID-19 Pneumonia: Effect on the Hypoxic and Inflammatory State

Remdesivir is one of the most attractive options for patients with hypoxemic respiratory failure due to coronavirus disease 2019 (COVID-19). The aim of our study was to evaluate the effect of remdesivir on the hypoxic and inflammatory state in patients with moderate to severe COVID-19. We retrospectively enrolled 112 patients admitted for COVID-19 pneumonia, requiring low-flow oxygen, 57 treated with remdesivir plus standard of care (SoC) and 55 treated only with SoC that were similar for demographic and clinical data. We evaluated changes in hypoxemia and inflammatory markers at admission (Day 0) and after 5 days of treatment (Day 5) and the clinical course of the disease. From Day 0 to Day 5, the ratio of arterial oxygen partial pressure to fractional inspired oxygen (P/F) increased from 222 ± 62 to 274 ± 97 (p < 0.0001) in the remdesivir group and decreased from 223 ± 62 to 183 ± 76 (p < 0.05) in the SoC group. Interleukine-6 levels decreased in the remdesivir (45.9 to 17.5 pg/mL, p < 0.05) but not in the SoC group. Remdesivir reduced the need for ventilatory support and the length of hospitalization. In conclusion, compared to standard care, remdesivir rapidly improves hypoxia and inflammation, causing a better course of the disease in moderate to severe COVID-19.

A retrospective real-world study of early short-course remdesivir in non-hospitalized COVID-19 patients at high risk for progression: low rate of hospitalization or death, regardless of immunocompetence status

Introduction: The evidence for remdesivir therapy in immunocompromised patients is scarce. To evaluate remdesivir (RDV) effectiveness and safety in COVID-19 outpatients at high risk for progression in a real-world setting, we compare the outcome in immunocompromised (IC) patients with that in non-immunocompromised patients. Methods: Two hospitals conducted a retrospective study of all adult patients with mild-to-moderate SARS-CoV-2 infection at high risk for disease progression who were treated as outpatients with a 3-day course of RDV (1st January-30th September 2022). The primary effectiveness endpoint was a composite of any cause of hospitalization or death by day 30. A multiple logistic regression model was built to explore the association between immune status and clinical outcome, estimating adjusted odds ratios [aORs (95% CI)]. Results: We have included 211 patients, of which 57% were males, with a median age of 65 years (IQR 53-77), 70.1% were vaccinated (three or four doses), and 61.1% were IC. The median duration of symptoms before RDV treatment was 3 days (IQR 2-5). During follow-up, 14 (6.6%) patients were hospitalized, of which 6 (2.8%) were hospitalized for COVID-19 progression. No patient required mechanical ventilation, and two patients died (non-COVID-19-related). After accounting for potential confounders, only anti-CD20 treatment was associated with the composed outcome [aOR 5.35 (1.02-27.5, 95% CI)], whereas the immunocompetence status was not [aOR 1.94 (0.49-7.81, 95% CI)]. Conclusion: Early COVID-19 outpatient treatment with a 3-day course of remdesivir in vaccinated patients at high risk for disease progression during the Omicron surge had a good safety profile. It was associated with a low rate of all-cause hospitalization or death, regardless of immunocompetence status.

Remdesivir or Nirmatrelvir/Ritonavir Therapy for Omicron SARS-CoV-2 Infection in Hematological Patients and Cell Therapy Recipients

BACKGROUND

Scarce data exist that analyze the outcomes of hematological patients with SARS-CoV-2 infection during the Omicron variant period who received treatment with remdesivir or nirmatrelvir/ritonavir.

METHODS

This study aims to address this issue by using a retrospective observational registry, created by the Spanish Hematopoietic Stem Cell Transplantation and Cell Therapy Group, spanning from 27 December 2021 to 30 April 2023.

RESULTS

This study included 466 patients, 243 (52%) who were treated with remdesivir and 223 (48%) with nirmatrelvir/ritonavir. Nirmatrelvir/ritonavir was primarily used for mild cases, resulting in a lower COVID-19-related mortality rate (1.3%), while remdesivir was preferred for moderate to severe cases (40%), exhibiting a higher mortality rate (9%). A multivariate analysis in the remdesivir cohort showed that male gender (odds ratio (OR) 0.35, p = 0.042) correlated with a lower mortality risk, while corticosteroid use (OR 9.4, p < 0.001) and co-infection (OR 2.8, p = 0.047) were linked to a higher mortality risk. Prolonged virus shedding was common, with 52% of patients shedding the virus for more than 25 days. In patients treated with remdesivir, factors associated with prolonged shedding included B-cell malignancy as well as underlying disease, severe disease, a later onset of and shorter duration of remdesivir treatment and a higher baseline viral load. Nirmatrelvir/ritonavir demonstrated a comparable safety profile to remdesivir, despite a higher risk of drug interactions.

CONCLUSIONS

Nirmatrelvir/ritonavir proved to be a safe and effective option for treating mild cases in the outpatient setting, while remdesivir was preferred for severe cases, where corticosteroids and co-infection significantly predicted worse outcomes. Despite antiviral therapy, prolonged shedding remains a matter of concern.

Changes in Lymphocyte Subpopulations after Remdesivir Therapy for COVID-19: A Brief Report

Remdesivir (RDV) has demonstrated clinical benefit in hospitalized COronaVIrus Disease (COVID)-19 patients. The objective of this brief report was to assess a possible correlation between RDV therapy and the variation in lymphocyte subpopulations. We retrospectively studied 43 hospitalized COVID-19 patients: 30 men and 13 women (mean age 69.3 ± 15 years); 9/43 had received RDV therapy. Six patients had no need for oxygen (severity group 0); 22 were on oxygen treatment with a fraction of inspired oxygen (FiO2) ≤ 50% (group 1); 7 on not-invasive ventilation (group 2); 3 on invasive mechanical ventilation (group 3); and 5 had died (group 4). Cytofluorimetric assessment of lymphocyte subpopulations showed substantial changes after RDV therapy: B lymphocytes and plasmablasts were significantly increased (p = 0.002 and p = 0.08, respectively). Cytotoxic T lymphocytes showed a robust reduction (p = 0.008). No changes were observed in CD4+-T cells and natural killers (NKs). There was a significant reduction in regulatory T cells (Tregs) (p = 0.02) and a significant increase in circulating monocytes (p = 0.03). Stratifying by disease severity, after RDV therapy, patients with severity 0-2 had significantly higher B lymphocyte and monocyte counts and lower memory and effector cytotoxic T cell counts. Instead, patients with severity 3-4 had significantly higher plasmablast and lower memory T cell counts. No significant differences for CD4+-T cells, Tregs, and NKs were observed. Our brief report showed substantial changes in the lymphocyte subpopulations analyzed between patients who did not receive RDV therapy and those after RDV treatment. Despite the small sample size, due to the retrospective nature of this brief report, the substantial changes in lymphocyte subpopulations reported could lead to speculation on the role of RDV treatment both on immune responses against the virus and on the possible downregulation of the cytokine storm observed in patients with more severe disease.

A systematic review and meta-analysis of randomized controlled trials with trial sequence analysis of remdesivir for COVID-19 treatment

Remdesivir is one of the proposed therapies for the corona virus disease 2019 (COVID-19). To assess the effect of remdesivir on mortality, need for invasive mechanical ventilation (IMV) and extracorporeal membrane oxygenation (ECMO), time to clinical improvement, and significant adverse effects. The study protocol was prospectively registered with The International Prospective Register of Systematic Reviews (Registration #CRD42021283221). Randomized controlled trials (RCTs) published in English detailing use of remdesivir in hospitalized patients with COVID-19 were included. Primary outcome was in hospital mortality among patients receiving remdesivir. Secondary outcomes were need for IMV and ECMO, time to clinical recovery, and significant adverse effects associated with remdesivir. Odds ratios (ORs) of worse outcome with 95% confidence interval (CI) in a forest plot were used to show the results of random effects meta-analysis. Remdesivir and placebo had similar in hospital mortality in the pooled analysis of five RCTs (OR: 0.93, 95% CI: 0.82-1.06). The remdesivir group needed less IMV/ECMO (OR: 0.59, 95% CI: 0.46-0.76) and recovered 1.06 days faster than placebo. Remdesivir did not affect transaminitis or renal damage. Trial sequence analysis showed that death has not reached the number of instances needed to predict futility. This meta-analysis shows that remdesivir therapy for COVID-19 is not associated with a mortality benefit. However, there is significant reduction in the need for IMV/ECMO.

Remdesivir Is Associated With Reduced Mortality in COVID-19 Patients Requiring Supplemental Oxygen Including Invasive Mechanical Ventilation Across SARS-CoV-2 Variants

Background

This comparative effectiveness study investigated the effect of remdesivir on in-hospital mortality among patients hospitalized for coronavirus disease 2019 (COVID-19) requiring supplemental oxygen including low-flow oxygen (LFO), high-flow oxygen/noninvasive ventilation (HFO/NIV), or invasive mechanical ventilation/extracorporeal membrane oxygenation (IMV/ECMO) across variant of concern (VOC) periods.

Methods

Patients hospitalized for COVID-19 between December 2020 and April 2022 and administered remdesivir upon admission were 1:1 propensity score matched to patients not administered remdesivir during their COVID-19 hospitalization. Analyses were stratified by supplemental oxygen requirement upon admission and VOC period. Cox proportional hazards models were used to derive adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) for 14- and 28-day mortality.

Results

Patients treated with remdesivir (67 582 LFO, 34 857 HFO/NIV, and 4164 IMV/ECMO) were matched to non-remdesivir patients. Unadjusted mortality rates were significantly lower for remdesivir-treated patients at 14 days (LFO: 6.4% vs. 8.8%; HFO/NIV: 16.8% vs. 19.4%; IMV/ECMO: 27.8% vs. 35.3%) and 28 days (LFO: 9.8% vs. 12.3%; HFO/NIV: 25.8% vs. 28.3%; IMV/ECMO: 41.4% vs. 50.6%). After adjustment, remdesivir treatment was associated with a statistically significant reduction in in-hospital mortality at 14 days (LFO: aHR, 0.72; 95% CI, 0.66-0.79; HFO/NIV: aHR, 0.83; 95% CI, 0.77-0.89; IMV/ECMO: aHR, 0.73; 95% CI, 0.65-0.82) and 28 days (LFO: aHR, 0.79; 95% CI, 0.73-0.85; HFO/NIV: aHR, 0.88; 95% CI, 0.82-0.93; IMV/ECMO: aHR, 0.74; 95% CI, 0.67-0.82) compared with non-remdesivir treatment. Lower risk of mortality among remdesivir-treated patients was observed across VOC periods.

Conclusions

Remdesivir treatment is associated with significantly reduced mortality among patients hospitalized for COVID-19 requiring supplemental oxygen upon admission, including those requiring HFO/NIV or IMV/ECMO with severe or critical disease, across VOC periods.

Early 3‑day course of remdesivir for the prevention of the progression to severe COVID‑19 in the elderly: A single‑centre, real‑life cohort study

Remdesivir, a viral RNA polymerase inhibitor, has constituted a key component of therapeutic regimens against the pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Originally approved for administration in hospitalized patients, remdesivir leads to improved outcomes in patients with moderate to severe coronavirus disease 2019 (COVID-19). After proving to be effective in hospitalized patients, its use gained approval in early-stage disease for symptomatic outpatients who are at a high risk of progression to severe disease. The present study is a real-life prospective cohort study involving 143 elderly non-hospitalized patients with SARS-CoV-2 (≥65 years of age) who attended the emergency department of the authors' hospital seeking care for COVID-19 symptoms appearing within the prior 7 days. Eligible patients received intravenous remdesivir at a dose of 200 mg on the first day and 100 mg on days 2 and 3. The efficacy endpoints were set as the need for COVID-19-related hospitalization and all-cause mortality in the following 28 days. A total of 143 patients participated in the study. Of these patients, 118 (82.5%) patients were vaccinated with at least two doses. All patients enrolled completed the 3-day course, with a total of 6 out of 143 patients (4.2%) having a COVID-19-related hospitalization by day 28, and 5 patients (3.5%) succumbing to the disease within the study period. In the univariate Cox regression analysis, the neutrophil-to-lymphocyte ratio and haematological malignancy were identified as predictors of progression to severe disease, and albumin levels, the C-reactive protein-to-albumin ratio (CAR) and haematological malignancy were identified as predictors of 28-day mortality. On the whole, the findings of the present study demonstrated that among the elderly outpatients, a 3-day course of intravenous remdesivir was associated with favourable outcomes.

Associations between COVID-19 therapies and inpatient gastrointestinal bleeding: A multisite retrospective study

Little data is available regarding the incidence of gastrointestinal bleeding in adults hospitalized with COVID-19 infection and the influence of patient comorbidities and demographics, COVID-19 therapies, and typical medications used. In this retrospective study, we utilized the National COVID Cohort Collaborative to investigate the primary outcome of the development of gastrointestinal bleeding in 512 467 hospitalized US adults (age >18 years) within 14 days of a COVID-19 infection and the influence of demographics, comorbidities, and selected medications. Gastrointestinal bleeding developed in 0.44% of patients hospitalized with COVID-19. Comorbidities associated with gastrointestinal bleeding include peptic ulcer disease (adjusted odds ratio [aOR] 10.2), obesity (aOR 1.27), chronic kidney disease (aOR 1.20), and tobacco use disorder (aOR 1.28). Lower risk of gastrointestinal bleeding was seen among women (aOR 0.76), Latinx (aOR 0.85), and vaccinated patients (aOR 0.74). Dexamethasone alone or with remdesivir was associated with lower risk of gastrointestinal bleeding (aOR 0.69 and aOR 0.83, respectively). Remdesivir monotherapy was associated with upper gastrointestinal bleeding (aOR 1.25). Proton pump inhibitors were more often prescribed in patients with gastrointestinal bleeding, likely representing treatment for gastrointestinal bleeding rather than a risk factor for its development. In adult patients hospitalized with COVID-19, the use of dexamethasone alone or in combination with remdesivir is negatively associated with gastrointestinal bleeding. Remdesivir monotherapy is associated with increased risk of upper gastrointestinal bleeding.

Real-World Experience of the Comparative Effectiveness and Safety of Combination Therapy with Remdesivir and Monoclonal Antibodies versus Remdesivir Alone for Patients with Mild-to-Moderate COVID-19 and Immunosuppression: A Retrospective Single-Center Study in Aichi, Japan

The coronavirus disease (COVID-19) pandemic continues to threaten global public health. Remdesivir and monoclonal antibodies have shown promise for COVID-19 treatment of patients who are immunocompromised, including those with cancer, transplant recipients, and those with autoimmune disorder. However, the effectiveness and safety of this combination therapy for patients who are immunosuppressed remain unclear. We compared the efficacy and safety of combination therapy and remdesivir monotherapy for patients with mild-to-moderate COVID-19 who were immunosuppressed. Eighty-six patients treated in July 2021-March 2023 were analyzed. The combination therapy group (CTG) showed a statistically significant reduction in viral load compared with the monotherapy group (MTG) (p < 0.01). Patients in the CTG also experienced earlier resolution of fever than those in the MTG (p = 0.02), although this difference was not significant in the multivariate analysis (p = 0.21). Additionally, the CTG had significantly higher discharge rates on days 7, 14, and 28 than the MTG (p < 0.01, p < 0.01, and p = 0.04, respectively). No serious adverse events were observed with combination therapy. These findings suggest that combination therapy may improve the clinical outcomes of immunosuppressed COVID-19 patients by reducing the viral load and hastening recovery. Further studies are required to fully understand the benefits of this combination therapy for immunocompromised COVID-19 patients.

Deuremidevir and Simnotrelvir-Ritonavir for the Treatment of COVID-19

Deuremidevir hydrobromide tablets and simnotrelvir tablets/ritonavir tablets (co-packaged) were approved by the Chinese National Medical Products Administration for the treatment of mild to moderate COVID-19 in January 2023. Both formulations contain small-molecule anti-SARS-CoV-2 agents. Deuremidevir, an oral nucleoside analog, is a broad-spectrum virus replication inhibitor targeting the highly conserved RNA-dependent RNA polymerase. Simnotrelvir-ritonavir is a co-packaged combination drug consisting of simnotrelvir tablets and ritonavir tablets. Simnotrelvir is an oral antiviral agent targeting the 3-chymotrypsin-like protease, which is essential for SARS-CoV-2 viral replication. Previous clinical trials revealed that both deuremidevir and simnotrelvir-ritonavir were effective and well tolerated in the treatment of COVID-19.

Use of whole genome sequencing to identify low-frequency mutations in SARS-CoV-2 patients treated with remdesivir

BACKGROUND

Remdesivir (RDV) has been shown to reduce hospitalization and mortality in COVID-19 patients. Resistance mutations caused by RDV are rare and have been predominantly reported in patients who are on prolonged therapy and immunocompromised. We investigate the effects of RDV treatment on intra-host SARS-CoV-2 diversity and low-frequency mutations in moderately ill hospitalized COVID-19 patients and compare them to patients without RDV treatment.

METHODS

From March 2020 to April 2022, sequential collections of nasopharyngeal and mid-turbinate swabs were obtained from 14 patients with and 30 patients without RDV treatment. Demographic and clinical data on all patients were reviewed. A total of 109 samples were sequenced and mutation analyses were performed.

RESULTS

Previously reported drug resistant mutations in nsp12 were not identified during short courses of RDV therapy. In genes encoding and surrounding the replication complex (nsp6-nsp14), low-frequency minority variants were detected in 7/14 (50%) and 18/30 (60%) patients with and without RDV treatment, respectively. We did not detect significant differences in within-host diversity and positive selection between the RDV-treated and untreated groups.

CONCLUSIONS

Minimal intra-host variability and stochastic low-frequency variants detected in moderately ill patients suggests little selective pressure in patients receiving short courses of RDV. The barrier to RDV resistance is high in patients with moderate disease. Patients undergoing short regimens of RDV therapy should continue to be monitored.

Effect of interferon-α on COVID-19 in-hospital mortality: a large-scale propensity score-matched study

BACKGROUND

 Coronavirus infection can induce the production of inflammatory cytokines leading to acute respiratory distress syndrome (ARDS) and death. It is well-established that interferons (IFNs) are essential in regulating the immune response, thus their effects of IFNs on COVID-19 patients should be subject to investigation. This study aimed to investigate the effects of IFN-α alone or in combination with remdesivir in hospitalized COVID-19 patients.

MATERIAL AND METHODS

 A multicentre, retrospective study was conducted on COVID-19 patients admitted to three hospitals in Tehran, Iran, from March 20, 2020, to March 18, 2021. The unadjusted and adjusted effects of IFN-α on COVID-19 outcomes were investigated through propensity score matching (PSM) to achieve a 1:1 balanced dataset.

RESULTS

Among 4,782 patients, 3,764 were eligible for the study, including 1,704 patients (45.27%) receiving at least one treatment with IFN-α and 2,060 controls not receiving IFN-α. After PSM, 851 IFN-α patients and 851 controls were recruited in the PSM analysis with a median age of 60.8 (standard deviation [SD]: 16.2 and 60.9 [SD: 17.4]), respectively. The PSM results showed no significant difference between the survival curves of the IFN-α group and the control group (p=0.340). However, the unadjusted impact of IFN-α on the risk of mortality was statistically significant (p=0.043, hazard-ratio: 0.86; 95% confidence interval [CI]: 0.75-0.99). Also, the combination of IFN-α and remdesivir had no significant benefit (HR: 89, 95% CI: 0.74-1.34).

CONCLUSION

Our findings indicate that subcutaneous administration of IFN-α, with or without remdesivir, does not have any significant impact on COVID-19 mortality and ICU admission. Future clinical trials considering the time, subtype, and form of IFN-α administration are warranted to investigate the potential therapeutic effects of IFN-α on COVID-19.

Severe COVID-19 Infection in an Infant With 8p Inverted Duplication/Deletion Syndrome: Is Vaccination Still a Debate?

Despite having a milder course of coronavirus disease 2019 (COVID-19) in comparison to adults, children are at risk for more significant complications, including acute neurological, renal, respiratory, and cardiovascular complications. Acute complications can manifest as encephalopathy, renal injury, interstitial pneumonia, and heart failure. However, the most severe complication is multisystem inflammatory syndrome in children, which often requires intensive care to manage the subsequent respiratory failure. Moreover, children with comorbidities such as chronic lung disease, neurological disorders, and cardiovascular disease are at an elevated risk of morbidity and mortality. Here, we present the case of an 11-month-old white female patient, previously unvaccinated against COVID-19, with chronic lung disease and the 8p inverted duplication/deletion (Inv dup del (8p)) syndrome who suffered from a severe COVID-19 infection. Initially presenting to the pediatric clinic with nasal congestion and respiratory distress, the patient's condition rapidly deteriorated which necessitated immediate transfer to the nearest pediatric tertiary center. There, she was mechanically ventilated, received dexamethasone and remdesivir, and was hospitalized for 26 days, nine of which were in the pediatric intensive care unit. To date, there is no current literature on Inv dup del (8p) syndrome as a predisposing factor for severe COVID-19 infection. Therefore, further investigation is needed to determine if Inv dup del (8p) can predispose a patient to having a severe COVID-19 course.

Prolonged Exposure to Remdesivir Inhibits the Human Ether-A-Go-Go-Related Gene Potassium Current

ABSTRACT

Remdesivir, approved for the treatment of COVID-19, has been associated with heart-rate corrected QT interval (QTc) prolongation and torsade de pointes in case reports. However, data are conflicting regarding the ability of remdesivir to inhibit the human ether-a-go-go-related gene (hERG) -related current. The objective of this study was to investigate the effects remdesivir and its primary metabolite, GS-441524, on hERG-related currents. Human embryonic kidney 293 cells stably expressing hERG were treated with various concentrations of remdesivir and GS-441524. The effects of acute and prolonged exposure on hERG-related current were assessed using whole-cell configuration of voltage-clamp protocols. Acute exposure to remdesivir and GS-441524 had no effect on hERG currents and the half-activation voltage (V 1/2 ). Prolonged treatment with 100 nM and 1 µM remdesivir significantly reduced peak tail currents and hERG current density. The propensity for remdesivir to prolong QTc intervals and induce torsade de pointes in predisposed patients warrants further investigation.

A mutation in the coronavirus nsp13-helicase impairs enzymatic activity and confers partial remdesivir resistance

Coronaviruses (CoVs) encode nonstructural proteins 1-16 (nsps 1-16) which form replicase complexes that mediate viral RNA synthesis. Remdesivir (RDV) is an adenosine nucleoside analog antiviral that inhibits CoV RNA synthesis. RDV resistance mutations have been reported only in the nonstructural protein 12 RNA-dependent RNA polymerase (nsp12-RdRp). We here show that a substitution mutation in the nsp13-helicase (nsp13-HEL A335V) of the betacoronavirus murine hepatitis virus (MHV) that was selected during passage with the RDV parent compound confers partial RDV resistance independently and additively when expressed with co-selected RDV resistance mutations in the nsp12-RdRp. The MHV A335V substitution did not enhance replication or competitive fitness compared to WT MHV and remained sensitive to the active form of the cytidine nucleoside analog antiviral molnupiravir (MOV). Biochemical analysis of the SARS-CoV-2 helicase encoding the homologous substitution (A336V) demonstrates that the mutant protein retained the ability to associate with the core replication proteins nsps 7, 8, and 12 but had impaired helicase unwinding and ATPase activity. Together, these data identify a novel determinant of nsp13-HEL enzymatic activity, define a new genetic pathway for RDV resistance, and demonstrate the importance of surveillance for and testing of helicase mutations that arise in SARS-CoV-2 genomes. IMPORTANCE Despite the development of effective vaccines against COVID-19, the continued circulation and emergence of new variants support the need for antivirals such as RDV. Understanding pathways of antiviral resistance is essential for surveillance of emerging variants, development of combination therapies, and for identifying potential new targets for viral inhibition. We here show a novel RDV resistance mutation in the CoV helicase also impairs helicase functions, supporting the importance of studying the individual and cooperative functions of the replicase nonstructural proteins 7-16 during CoV RNA synthesis. The homologous nsp13-HEL mutation (A336V) has been reported in the GISAID database of SARS-CoV-2 genomes, highlighting the importance of surveillance of and genetic testing for nucleoside analog resistance in the helicase.

Spray-Dried Inhalable Microparticles Combining Remdesivir and Ebselen against SARS-CoV-2 Infection

There is a continuous effort to develop efficient treatments for coronavirus disease 2019 (COVID-19) and other viral respiratory diseases. Among the different strategies, inhaled treatment is considered one of the most logical and efficient approaches to treating COVID-19, as the causative "SARS-CoV-2 virus RNA" predominantly infects the respiratory tract. COVID-19 treatments initially relied on repurposed drugs, with a few additional strategies developed during the last two years, and all of them are based on monotherapy. However, drug combinations have been found to be more effective than monotherapy in other viral diseases such as HIV, influenza, and hepatitis C virus. In the case of SARS-CoV-2 infection, in vitro studies have shown synergistic antiviral activity combining remdesivir with ebselen, an organoselenium compound. Therefore, these drug combinations could ensure better therapeutic outcomes than the individual agents. In this study, we developed a dry powder formulation containing remdesivir and ebselen using a spray-drying technique and used L-leucine as an aerosolization enhancer. The prepared dry powders were spherical and crystalline, with a mean particle size between 1 and 3 µm, indicating their suitability for inhalation. The emitted dose (ED) and fine particle fraction (FPF) of remdesivir- and ebselen-containing dry powders were ~80% and ~57% when prepared without L-leucine. The ED as well as the FPF significantly increased with values of >86% and >67%, respectively, when L-leucine was incorporated. More importantly, the single and combinational dry powder of remdesivir and ebselen showed minimal cytotoxicity (CC50 > 100 μM) in Calu-3 cells, retaining their anti-SARS-CoV-2 properties (EC50 2.77 to 18.64 μM). In summary, we developed an inhalable dry powder combination of remdesivir and ebselen using a spray-drying technique. The spray-dried inhalable microparticles retained their limited cytotoxicity and specific antiviral properties. Future in vivo studies are needed to verify the potential use of these remdesivir/ebselen combinational spray-dried inhalable microparticles to block the SARS-CoV-2 replication in the respiratory tract.

Transient SARS-CoV-2 RNA-Dependent RNA Polymerase Mutations after Remdesivir Treatment for Chronic COVID-19 in Two Transplant Recipients: Case Report and Intra-Host Viral Genomic Investigation

Remdesivir is the first FDA-approved drug for treating severe SARS-CoV-2 infection and targets RNA-dependent RNA polymerase (RdRp) that is required for viral replication. To monitor for the development of mutations that may result in remdesivir resistance during prolonged treatment, we sequenced SARS-CoV-2 specimens collected at different treatment time points in two transplant patients with severe COVID-19. In the first patient, an allogeneic hematopoietic stem cell transplant recipient, a transient RdRp catalytic subunit mutation (nsp12:A449V) was observed that has not previously been associated with remdesivir resistance. As no in vitro study had been conducted to elucidate the phenotypic effect of nsp12:A449V, its clinical significance is unclear. In the second patient, two other transient RdRp mutations were detected: one in the catalytic subunit (nsp12:V166A) and the other in an accessory subunit important for processivity (nsp7:D67N). This is the first case report for a potential link between the nsp12:V166A mutation and remdesivir resistance in vivo, which had only been previously described by in vitro studies. The nsp7:D67N mutation has not previously been associated with remdesivir resistance, and whether it has a phenotypic effect is unknown. Our study revealed SARS-CoV-2 genetic dynamics during remdesivir treatment in transplant recipients that involved mutations in the RdRp complex (nsp7 and nsp12), which may be the result of selective pressure. These results suggest that close monitoring for potential resistance during the course of remdesivir treatment in highly vulnerable patient populations may be beneficial. Development and utilization of diagnostic RdRp genotyping tests may be a future direction for improving the management of chronic COVID-19.

Molecular and Structural Aspects of Clinically Relevant Mutations of SARS-CoV-2 RNA-Dependent RNA Polymerase in Remdesivir-Treated Patients

(1) Background: SARS-CoV-2 RNA-dependent RNA polymerase (RdRp) is a promising therapeutic target to fight COVID-19, and many RdRp inhibitors nucleotide/nucleoside analogs, such as remdesivir, have been identified or are in clinical studies. However, the appearance of resistant mutations could reduce their efficacy. In the present work, we structurally evaluated the impact of RdRp mutations found at baseline in 39 patients treated with remdesivir and associated with a different degree of antiviral response in vivo. (2) Methods: A refined bioinformatics approach was applied to assign SARS-CoV-2 clade and lineage, and to define RdRp mutational profiles. In line with such a method, the same mutations were built and analyzed by combining docking and thermodynamics evaluations with both molecular dynamics and representative pharmacophore models. (3) Results: Clinical studies revealed that patients bearing the most prevalent triple mutant P323L+671S+M899I, which was present in 41% of patients, or the more complex mutational profile P323L+G671S+L838I+D738Y+K91E, which was found with a prevalence of 2.6%, showed a delayed reduced response to remdesivir, as confirmed by the increase in SARS-CoV-2 viral load and by a reduced theoretical binding affinity versus RdRp (ΔGbindWT = -122.70 kcal/mol; ΔGbindP323L+671S+M899I = -84.78 kcal/mol; ΔGbindP323L+G671S+L838I+D738Y+K91E = -96.74 kcal/mol). Combined computational approaches helped to rationalize such clinical observations, offering a mechanistic understanding of the allosteric effects of mutants on the global motions of the viral RNA synthesis machine and in the changes of the interactions patterns of remdesivir during its binding.

Study to compare the effect of casirivimab and imdevimab, remdesivir, and favipiravir on progression and multi-organ function of hospitalized COVID-19 patients

Coronavirus disease 2019 (COVID-19) caused a progress in research to find a solution to this pandemic. Also, various advances in pharmacotherapy against COVID-19 have emerged. Regarding antiviral therapy, casirivimab and imdevimab are antibodies combination against COVID-19. Standard antiviral therapy against COVID-19 includes remdesivir and favipiravir. The objectives were to compare progression and multi-organ function of hospitalized COVID-19 patients between these three antiviral groups. 265 COVID-19 hospitalized patients were included in this study and were divided into 3 groups (1:2:2), respectively, Group (A): casirivimab and imdevimab, group (B): remdesivir, and group (C): favipiravir. The design of the study is a single blind non-randomized controlled trial. This study is a phase IV clinical trial (post-marketing study). The duration of the study was about 6 months after receiving the ethical approval. Casirivimab and imdevimab achieved less case progression as presented by lower World Health Organization scale (P < 0.05 in comparing group A with B and C) and better multi-organ functions as presented by lower Sequential Organ Function Assessment score (P < 0.05 in comparing group A with B and C) than remdesivir and favipiravir. From all these results, it is concluded that Group A (casirivimab and imdevimab) produces better outcomes than B (remdesivir) and C (favipiravir) intervention groups.