Evaluation of the Effects of Remdesivir and Hydroxychloroquine on Viral Clearance in COVID-19 : A Randomized Trial.

BACKGROUND: New treatment modalities are urgently needed for patients with COVID-19. The World Health Organization (WHO) Solidarity trial showed no effect of remdesivir or hydroxychloroquine (HCQ) on mortality, but the antiviral effects of these drugs are not known. OBJECTIVE: To evaluate the effects of remdesivir and HCQ on all-cause, in-hospital mortality; the degree of respiratory failure and inflammation; and viral clearance in the oropharynx. DESIGN: NOR-Solidarity is an independent, add-on, randomized controlled trial to the WHO Solidarity trial that included biobanking and 3 months of clinical follow-up (ClinicalTrials.gov: NCT04321616). SETTING: 23 hospitals in Norway. PATIENTS: Eligible patients were adults hospitalized with confirmed SARS-CoV-2 infection. INTERVENTION: Between 28 March and 4 October 2020, a total of 185 patients were randomly assigned and 181 were included in the full analysis set. Patients received remdesivir (n = 42), HCQ (n = 52), or standard of care (SoC) (n = 87). MEASUREMENTS: In addition to the primary end point of WHO Solidarity, study-specific outcomes were viral clearance in oropharyngeal specimens, the degree of respiratory failure, and inflammatory variables. RESULTS: No significant differences were seen between treatment groups in mortality during hospitalization. There was a marked decrease in SARS-CoV-2 load in the oropharynx during the first week overall, with similar decreases and 10-day viral loads among the remdesivir, HCQ, and SoC groups. Remdesivir and HCQ did not affect the degree of respiratory failure or inflammatory variables in plasma or serum. The lack of antiviral effect was not associated with symptom duration, level of viral load, degree of inflammation, or presence of antibodies against SARS-CoV-2 at hospital admittance. LIMITATION: The trial had no placebo group. CONCLUSION: Neither remdesivir nor HCQ affected viral clearance in hospitalized patients with COVID-19. PRIMARY FUNDING SOURCE: National Clinical Therapy Research in the Specialist Health Services, Norway.

Immune complexes, innate immunity, and NETosis in ChAdOx1 vaccine-induced thrombocytopenia.

AIMS: We recently reported five cases of vaccine-induced immune thrombotic thrombocytopenia (VITT) 7-10 days after receiving the first dose of the ChAdOx1 nCoV-19 adenoviral vector vaccine against corona virus disease 2019 (COVID-19). We aimed to investigate the pathogenic immunological responses operating in these patients. METHODS AND RESULTS: We assessed circulating inflammatory markers by immune assays and immune cell phenotyping by flow cytometry analyses and performed immunoprecipitation with anti-platelet factor (PF)4 antibody in plasma samples followed by mass spectrometry from all five patients. A thrombus was retrieved from the sinus sagittal superior of one patient and analysed by immunohistochemistry and flow cytometry. Precipitated immune complexes revealed multiple innate immune pathway triggers for platelet and leucocyte activation. Plasma contained increased levels of innate immune response cytokines and markers of systemic inflammation, extensive degranulation of neutrophils, and tissue and endothelial damage. Blood analyses showed activation of neutrophils and increased levels of circulating H3Cit, dsDNA, and myeloperoxidase-DNA complex. The thrombus had extensive infiltration of neutrophils, formation of neutrophil extracellular traps (NETs), and IgG deposits. CONCLUSIONS: The results show that anti-PF4/polyanion IgG-mediated thrombus formation in VITT patients is accompanied by a massive innate immune activation and particularly the fulminant activation of neutrophils including NETosis. These results provide novel data on the immune response in this rare adenoviral vector-induced VITT.

Rapid SARS-CoV-2 variant monitoring using PCR confirmed by whole genome sequencing in a high-volume diagnostic laboratory.

OBJECTIVES: The emerging SARS-CoV-2 variants of concern (VoC), B.1.1.7, B.1.351 and P.1, with increased transmission and/or immune evasion, emphasise the need for broad and rapid variant monitoring. Our high-volume laboratory introduced a PCR variant assay (Variant PCR) in January 2021 based on the protocol by Vogels et al. STUDY DESIGN: To assess whether Variant PCR could be used for rapid B.1.1.7, B.1.351 and P.1 screening, all positive SARS-CoV-2 airway samples were prospectively tested in parallel using both the Variant PCR and whole genome sequencing (WGS). RESULTS: In total 1,642 SARS-CoV-2 positive samples from individual patients were tested within a time span of 4 weeks. For all samples with valid results from both Variant PCR and WGS, no VoC was missed by Variant PCR (totalling 399 VoC detected). Conversely, all of the samples identified as "other lineages" (i.e., "non-VoC lineages") by the Variant PCR, were confirmed by WGS. CONCLUSIONS: The Variant PCR based on the protocol by Vogels et al., is an effective method for rapid screening for VoC, applicable for most diagnostic laboratories within a pandemic setting. WGS is still required to confirm the identity of certain variants and for continuous surveillance of emerging VoC.

Systemic complement activation is associated with respiratory failure in COVID-19 hospitalized patients.

Respiratory failure in the acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic is hypothesized to be driven by an overreacting innate immune response, where the complement system is a key player. In this prospective cohort study of 39 hospitalized coronavirus disease COVID-19 patients, we describe systemic complement activation and its association with development of respiratory failure. Clinical data and biological samples were obtained at admission, days 3 to 5, and days 7 to 10. Respiratory failure was defined as PO2/FiO2 ratio of ≤40 kPa. Complement activation products covering the classical/lectin (C4d), alternative (C3bBbP) and common pathway (C3bc, C5a, and sC5b-9), the lectin pathway recognition molecule MBL, and antibody serology were analyzed by enzyme-immunoassays; viral load by PCR. Controls comprised healthy blood donors. Consistently increased systemic complement activation was observed in the majority of COVID-19 patients during hospital stay. At admission, sC5b-9 and C4d were significantly higher in patients with than without respiratory failure (P = 0.008 and P = 0.034). Logistic regression showed increasing odds of respiratory failure with sC5b-9 (odds ratio 31.9, 95% CI 1.4 to 746, P = 0.03) and need for oxygen therapy with C4d (11.7, 1.1 to 130, P = 0.045). Admission sC5b-9 and C4d correlated significantly to ferritin (r = 0.64, P < 0.001; r = 0.69, P < 0.001). C4d, sC5b-9, and C5a correlated with antiviral antibodies, but not with viral load. Systemic complement activation is associated with respiratory failure in COVID-19 patients and provides a rationale for investigating complement inhibitors in future clinical trials.