ABSTRACT
BACKGROUND: SARS-CoV-2 infection is associated with a significant risk of hospitalisation, death, and prolonged impact on quality of life. Evaluation of new treatment options and optimising therapeutic management of people hospitalised with SARS-CoV-2 infection remains essential, but rapid changes in pandemic conditions and potential therapies have limited the utility of traditional approaches to randomised controlled trials. METHODS: ASCOT ADAPT is an international, investigator-initiated, adaptive platform, randomised controlled trial of therapeutics for non-critically ill patients hospitalised with COVID-19. The study design is open label and pragmatic. Potential participants are hospitalised adults with PCR confirmed, symptomatic, SARS-CoV-2 infection, within 14 days of symptom onset. Domains include antiviral, antibody and anticoagulant interventions, with a composite primary outcome of 28-day mortality or progression to intensive-care level respiratory or haemodynamic support. Initial interventions include intravenous nafamostat and variable dose anticoagulation. A range of secondary endpoints, and substudies for specific domains and interventions are outlined. DISCUSSION: This paper presents the trial protocol and management structure, including international governance, remote site monitoring and biobanking activities and provides commentary on ethical and pragmatic considerations in establishing the ASCOT ADAPT trial under pandemic conditions. TRIAL REGISTRATION: Australian and New Zealand Clinical Trials Registry (ACTRN12620000445976) and ClinicalTrials.gov (NCT04483960).
Subject(s)
COVID-19 , Adult , Humans , SARS-CoV-2 , Quality of Life , Biological Specimen Banks , Australia , Treatment OutcomeABSTRACT
The search for clinically effective antivirals against the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is ongoing. Repurposing of drugs licensed for non-coronavirus disease 2019 (COVID-19) indications has been extensively investigated in laboratory models and in clinical studies with mixed results. Nafamostat mesylate (nafamostat) is a drug licensed in Japan and Korea for indications including acute pancreatitis and disseminated intravascular coagulation. It is available only for continuous intravenous infusion. In vitro human lung cell line studies with nafamostat demonstrate high antiviral potency against SARS-CoV-2 (half maximal inhibitory concentration [IC50] of 0.0022 µM [compared to remdesivir 1.3 µM]), ostensibly via inhibition of the cellular enzyme transmembrane protease serine 2 (TMPRSS2) preventing viral entry into human cells. In addition, the established antithrombotic activity is hypothesised to be advantageous given thrombosis-associated sequelae of COVID-19. Clinical reports to date are limited, but indicate a potential benefit of nafamostat in patients with moderate to severe COVID-19. In this review, we will explore the pre-clinical, pharmacokinetic and clinical outcome data presently available for nafamostat as a treatment for COVID-19. The recruitment to ongoing clinical trials is a priority to provide more robust data on the safety and efficacy of nafamostat as a treatment for COVID-19.
Subject(s)
COVID-19 Drug Treatment , Pancreatitis , Acute Disease , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , Benzamidines , Fibrinolytic Agents/therapeutic use , Guanidines , Humans , Pancreatitis/drug therapy , SARS-CoV-2 , Serine/therapeutic useABSTRACT
BACKGROUND: Coronavirus disease 2019 (COVID-19) has exposed the disproportionate effects of pandemics on frontline workers and the ethical imperative to provide effective prophylaxis. We present a model for a pragmatic randomised controlled trial (RCT) that utilises Bayesian methods to rapidly determine the efficacy or futility of a prophylactic agent. METHODS: We initially planned to undertake a multicentre, phase III, parallel-group, open-label RCT, to determine if hydroxychloroquine (HCQ) taken once a week was effective in preventing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in healthcare workers (HCW) aged ≥ 18 years in New Zealand (NZ) and Ireland. Participants were to be randomised 2:1 to either HCQ (800 mg stat then 400 mg weekly) or no prophylaxis. The primary endpoint was time to Nucleic Acid Amplification Test-proven SARS-CoV-2 infection. Secondary outcome variables included mortality, hospitalisation, intensive care unit admissions and length of mechanical ventilation. The trial had no fixed sample size or duration of intervention. Bayesian adaptive analyses were planned to occur fortnightly, commencing with a weakly informative prior for the no prophylaxis group hazard rate and a moderately informative prior on the intervention log hazard ratio centred on 'no effect'. Stopping for expected success would be executed if the intervention had a greater than 0.975 posterior probability of reducing the risk of SARS-CoV-2 infection by more than 10%. Final success would be declared if, after completion of 8 weeks of follow-up (reflecting the long half-life of HCQ), the prophylaxis had at least a 0.95 posterior probability of reducing the risk of SARS-CoV-2 infection by more than 10%. Futility would be declared if HCQ was shown to have less than a 0.10 posterior probability of reducing acquisition of SARS-CoV-2 infection by more than 20%. DISCUSSION: This study did not begin recruitment due to the marked reduction in COVID-19 cases in NZ and concerns regarding the efficacy and risks of HCQ treatment in COVID-19. Nonetheless, the model presented can be easily adapted for other potential prophylactic agents and pathogens, and pre-established collaborative models like this should be shared and incorporated into future pandemic preparedness planning. TRIAL REGISTRATION: The decision not to proceed with the study was made before trial registration occurred.
Subject(s)
COVID-19 , Pandemics , COVID-19/prevention & control , Health Personnel , Humans , Hydroxychloroquine/adverse effects , Pandemics/prevention & control , SARS-CoV-2ABSTRACT
BACKGROUND: The mRNA COVID vaccines are only licensed for intramuscular injection but it is unclear whether successful intramuscular administration is required for immunogenicity. METHODS: In this observational study, eligible adults receiving their first ComirnatyTM/BNT162b2 dose had their skin to deltoid muscle distance (SDMD) measured by ultrasound. The relationship between SDMD and height, weight, body mass index, and arm circumference was assessed. Three needle length groups were identified: 'clearly sufficient' (needle exceeding SDMD by >5 mm), 'probably sufficient' (needle exceeding SDMD by ≤ 5 mm), and 'insufficient' (needle length ≤ SDMD). Baseline and follow-up finger prick blood samples were collected and the primary outcome variable was mean spike antibody levels in the three needle length groups. RESULTS: Participants (n = 402) had a mean age of 34.7 years, BMI 29.1 kg/m2, arm circumference 37.5 cm, and SDMD 13.3 mm. The SDMD was >25 mm in 23/402 (5.7%) and >20 mm in 61/402 (15.2%) participants. Both arm circumference (≥40 cm) and BMI (≥33 kg/m2) were able to identify those with a SDMD of >25 mm, the length of a standard injection needle, with a sensitivity of 100% and specificities of 71.2 and 79.9%, respectively. Of 249/402 (62%) participants with paired blood samples, there was no significant difference in spike antibody titres between needle length groups. The mean (SD) spike BAU/mL was 464.5 (677.1) in 'clearly sufficient needle length' (n = 217) compared with 506.4 (265.1) in 'probably sufficient' (n = 21, p = 0.09), and 489.4 (452.3) in 'insufficient needle length' (n = 11, p = 0.65). CONCLUSIONS: A 25 mm needle length is likely to be inadequate to ensure vaccine deposition within the deltoid muscle in a small proportion of adults. Vaccine-induced spike antibody titres were comparable in those vaccinated with a needle of sufficient versus insufficient length suggesting deltoid muscle deposition may not be required for an adequate antibody response to mRNA vaccines.
Subject(s)
COVID-19 , Vaccines , Adult , Antibodies, Viral , BNT162 Vaccine , COVID-19 Vaccines , Deltoid Muscle , Humans , Immunogenicity, Vaccine , RNA, MessengerABSTRACT
AIM: As New Zealand transitions towards endemic SARS-CoV-2, understanding patient factors predicting severity, as well as hospital resourcing requirements will be essential for future planning. METHODS: We retrospectively enrolled patients hospitalised with COVID-19 from 26 February to 5 October 2020 as part of the COVID-19 HospitalisEd Patient SeverIty Observational Study NZ (COHESION). Data on demographics, clinical course and outcomes were collected and analysed as a descriptive case series. RESULTS: Eighty-four patients were identified across eight district health boards. Forty-one (49%) were male. The median age was 58 years [IQR: 41.7-70.3 years]. By ethnicity, hospitalisations included 38 NZ European (45%), 19 Pasifika (23%), 13 Maori (15%), 12 Asian (14%) and 2 Other (2%). Pre-existing co-morbidities included hypertension (26/82, 32%), obesity (16/66, 24%) and diabetes (18/81, 22%). The median length of stay was four days [IQR: 2-15 days]. Twelve patients (12/83, 14%) were admitted to an intensive care unit or high dependency unit (ICU/HDU). Ten (10/83, 12%) patients died in hospital of whom seven (70%) were not admitted to ICU/HDU; the median age at death was 83 years. CONCLUSION: Despite initially low case numbers in New Zealand during 2020, hospitalisation with COVID-19 was associated with a high mortality and hospital resource requirements.
Subject(s)
COVID-19 , Pandemics , COVID-19/epidemiology , Female , Hospital Mortality , Hospitalization , Humans , Intensive Care Units , Male , Middle Aged , New Zealand/epidemiology , Retrospective Studies , SARS-CoV-2ABSTRACT
Importance: The efficacy of antiplatelet therapy in critically ill patients with COVID-19 is uncertain. Objective: To determine whether antiplatelet therapy improves outcomes for critically ill adults with COVID-19. Design, Setting, and Participants: In an ongoing adaptive platform trial (REMAP-CAP) testing multiple interventions within multiple therapeutic domains, 1557 critically ill adult patients with COVID-19 were enrolled between October 30, 2020, and June 23, 2021, from 105 sites in 8 countries and followed up for 90 days (final follow-up date: July 26, 2021). Interventions: Patients were randomized to receive either open-label aspirin (n = 565), a P2Y12 inhibitor (n = 455), or no antiplatelet therapy (control; n = 529). Interventions were continued in the hospital for a maximum of 14 days and were in addition to anticoagulation thromboprophylaxis. Main Outcomes and Measures: The primary end point was organ support-free days (days alive and free of intensive care unit-based respiratory or cardiovascular organ support) within 21 days, ranging from -1 for any death in hospital (censored at 90 days) to 22 for survivors with no organ support. There were 13 secondary outcomes, including survival to discharge and major bleeding to 14 days. The primary analysis was a bayesian cumulative logistic model. An odds ratio (OR) greater than 1 represented improved survival, more organ support-free days, or both. Efficacy was defined as greater than 99% posterior probability of an OR greater than 1. Futility was defined as greater than 95% posterior probability of an OR less than 1.2 vs control. Intervention equivalence was defined as greater than 90% probability that the OR (compared with each other) was between 1/1.2 and 1.2 for 2 noncontrol interventions. Results: The aspirin and P2Y12 inhibitor groups met the predefined criteria for equivalence at an adaptive analysis and were statistically pooled for further analysis. Enrollment was discontinued after the prespecified criterion for futility was met for the pooled antiplatelet group compared with control. Among the 1557 critically ill patients randomized, 8 patients withdrew consent and 1549 completed the trial (median age, 57 years; 521 [33.6%] female). The median for organ support-free days was 7 (IQR, -1 to 16) in both the antiplatelet and control groups (median-adjusted OR, 1.02 [95% credible interval {CrI}, 0.86-1.23]; 95.7% posterior probability of futility). The proportions of patients surviving to hospital discharge were 71.5% (723/1011) and 67.9% (354/521) in the antiplatelet and control groups, respectively (median-adjusted OR, 1.27 [95% CrI, 0.99-1.62]; adjusted absolute difference, 5% [95% CrI, -0.2% to 9.5%]; 97% posterior probability of efficacy). Among survivors, the median for organ support-free days was 14 in both groups. Major bleeding occurred in 2.1% and 0.4% of patients in the antiplatelet and control groups (adjusted OR, 2.97 [95% CrI, 1.23-8.28]; adjusted absolute risk increase, 0.8% [95% CrI, 0.1%-2.7%]; 99.4% probability of harm). Conclusions and Relevance: Among critically ill patients with COVID-19, treatment with an antiplatelet agent, compared with no antiplatelet agent, had a low likelihood of providing improvement in the number of organ support-free days within 21 days. Trial Registration: ClinicalTrials.gov Identifier: NCT02735707.
Subject(s)
COVID-19 Drug Treatment , COVID-19 , Critical Illness , Platelet Aggregation Inhibitors , Venous Thromboembolism , Adult , Anticoagulants/adverse effects , Anticoagulants/therapeutic use , Aspirin/adverse effects , Aspirin/therapeutic use , Bayes Theorem , COVID-19/complications , COVID-19/mortality , COVID-19/therapy , Critical Illness/mortality , Critical Illness/therapy , Female , Hemorrhage/chemically induced , Humans , Male , Middle Aged , Platelet Aggregation Inhibitors/adverse effects , Platelet Aggregation Inhibitors/therapeutic use , Purinergic P2Y Receptor Antagonists/adverse effects , Purinergic P2Y Receptor Antagonists/therapeutic use , Respiration, Artificial , Venous Thromboembolism/drug therapy , Venous Thromboembolism/etiologyABSTRACT
PURPOSE: To study the efficacy of lopinavir-ritonavir and hydroxychloroquine in critically ill patients with coronavirus disease 2019 (COVID-19). METHODS: Critically ill adults with COVID-19 were randomized to receive lopinavir-ritonavir, hydroxychloroquine, combination therapy of lopinavir-ritonavir and hydroxychloroquine or no antiviral therapy (control). The primary endpoint was an ordinal scale of organ support-free days. Analyses used a Bayesian cumulative logistic model and expressed treatment effects as an adjusted odds ratio (OR) where an OR > 1 is favorable. RESULTS: We randomized 694 patients to receive lopinavir-ritonavir (n = 255), hydroxychloroquine (n = 50), combination therapy (n = 27) or control (n = 362). The median organ support-free days among patients in lopinavir-ritonavir, hydroxychloroquine, and combination therapy groups was 4 (- 1 to 15), 0 (- 1 to 9) and-1 (- 1 to 7), respectively, compared to 6 (- 1 to 16) in the control group with in-hospital mortality of 88/249 (35%), 17/49 (35%), 13/26 (50%), respectively, compared to 106/353 (30%) in the control group. The three interventions decreased organ support-free days compared to control (OR [95% credible interval]: 0.73 [0.55, 0.99], 0.57 [0.35, 0.83] 0.41 [0.24, 0.72]), yielding posterior probabilities that reached the threshold futility (≥ 99.0%), and high probabilities of harm (98.0%, 99.9% and > 99.9%, respectively). The three interventions reduced hospital survival compared with control (OR [95% CrI]: 0.65 [0.45, 0.95], 0.56 [0.30, 0.89], and 0.36 [0.17, 0.73]), yielding high probabilities of harm (98.5% and 99.4% and 99.8%, respectively). CONCLUSION: Among critically ill patients with COVID-19, lopinavir-ritonavir, hydroxychloroquine, or combination therapy worsened outcomes compared to no antiviral therapy.
Subject(s)
COVID-19 Drug Treatment , Ritonavir , Adult , Antiviral Agents/therapeutic use , Bayes Theorem , Critical Illness , Drug Combinations , Humans , Hydroxychloroquine/therapeutic use , Lopinavir/therapeutic use , Ritonavir/therapeutic use , SARS-CoV-2ABSTRACT
BACKGROUND: Severity of viral respiratory illnesses can be increased with bacterial coinfection and can vary by sex, but influence of coinfection and sex on human endemic coronavirus (CoV) species, which generally cause mild to moderate respiratory illness, is unknown. We evaluated CoV and pneumococcal co-detection by sex in childhood pneumonia. METHODS: In the 2011-2014 Pneumonia Etiology Research for Child Health study, nasopharyngeal and oropharyngeal (NP/OP) swabs and other samples were collected from 3981 children <5 years hospitalized with severe or very severe pneumonia in 7 countries. Severity by NP/OP detection status of CoV (NL63, 229E, OC43 or HKU1) and high-density (≥6.9 log10 copies/mL) pneumococcus (HDSpn) by real-time polymerase chain reaction was assessed by sex using logistic regression adjusted for age and site. RESULTS: There were 43 (1.1%) CoV+/HDSpn+, 247 CoV+/HDSpn-, 449 CoV-/HDSpn+ and 3149 CoV-/HDSpn- cases with no significant difference in co-detection frequency by sex (range 51.2%-64.0% male, P = 0.06). More CoV+/HDSpn+ pneumonia was very severe compared with other groups for both males (13/22, 59.1% versus range 29.1%-34.7%, P = 0.04) and females (10/21, 47.6% versus 32.5%-43.5%, P = 0.009), but only male CoV+/HDSpn+ required supplemental oxygen more frequently (45.0% versus 20.6%-28.6%, P < 0.001) and had higher mortality (35.0% versus 5.3%-7.1%, P = 0.004) than other groups. For females with CoV+/HDSpn+, supplemental oxygen was 25.0% versus 24.8%-33.3% (P = 0.58) and mortality was 10.0% versus 9.2%-12.9% (P = 0.69). CONCLUSIONS: Co-detection of endemic CoV and HDSpn was rare in children hospitalized with pneumonia, but associated with higher severity and mortality in males. Findings may warrant investigation of differences in severity by sex with co-detection of HDSpn and SARS-CoV-2.
Subject(s)
Coinfection/epidemiology , Coronavirus Infections/diagnosis , Pneumococcal Infections/diagnosis , Respiratory Tract Infections/diagnosis , Animals , COVID-19/diagnosis , COVID-19/epidemiology , COVID-19/virology , Child, Preschool , Coinfection/diagnosis , Coinfection/virology , Coronavirus , Coronavirus Infections/epidemiology , Coronavirus Infections/virology , Female , HIV Infections/epidemiology , HIV Infections/virology , Humans , Infant , Infant, Newborn , Logistic Models , Male , Nasopharynx/virology , Pneumococcal Infections/epidemiology , Pneumococcal Infections/virology , Pneumonia/diagnosis , Pneumonia/virology , Respiratory Tract Infections/epidemiology , Respiratory Tract Infections/virology , SARS-CoV-2/isolation & purification , Streptococcus pneumoniaeABSTRACT
We conducted a multicentre cross sectional observational study of laboratory, public health and hospitalisation data for PCR-confirmed COVID-19 cases within the New Zealand Northern Region, between 12 February and 8 June 2020. The aim of this study was to describe population level SARS-CoV-2 upper respiratory tract (URT) viral load dynamics by stratifying positivity rates and polymerase chain reaction (PCR) cycle threshold (Ct) values of URT samples from COVID-19 cases by days since symptom onset, and to explore utility of Ct values in determining length of time post-infection and thus potential infectivity. Of 123,124 samples tested for SARS-CoV-2 by PCR, 579 samples (407 positive and 172 negative) from 368 symptomatic non-hospitalised individuals with PCR-confirmed infection were included. Sample positivity rate was 61.5% (8/13) for pre-symptomatic samples, rising to 93.2% (317/340) for samples collected during the purported symptomatic infectious period (days 0-10 post-symptom onset), and dropping to 36.3% (82/226) for post-infectious period samples (day 11 onwards). URT viral load peaked shortly after symptom onset, with median Ct values ranging 20.00-29.99 until 15 days post-symptom onset, and >30.00 after this time. Of samples with a Ct value of <20.00, 96.1% were collected during the symptomatic infectious period. However, of samples with a Ct value ≥30.00 and ≥35.00, 46.9% and 18.5%, respectively, were also collected during the symptomatic infectious period. The findings of this study indicate that at or soon after symptom onset represents the optimum time to test for SARS-CoV-2 in the URT, with median Ct values suggesting the useful testing window extends until around 15 days post-symptom onset. In asymptomatic individuals or those with unknown dates of symptom onset, Ct values <20.00 imply recent onset/potential infectivity, but Ct values ≥30.00 or ≥35.00 do not exclude recent onset/potential infectivity. Individual sample Ct values should not be used as an absolute marker of length of time post-infection or to exclude infectivity where date of symptom onset is unavailable.
Subject(s)
COVID-19/virology , SARS-CoV-2 , Viral Load , Adolescent , Adult , Aged , Aged, 80 and over , COVID-19 Testing , Child , Child, Preschool , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , New Zealand , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Young AdultABSTRACT
OBJECTIVES: Circulating antibodies are important markers of previous infection and immunity. Questions remain with respect to the durability and functionality of SARS-CoV-2 antibodies. This study explored antibody responses in recovered COVID-19 patients in a setting where the probability of re-exposure is effectively nil, owing to New Zealand's successful elimination strategy. METHODS: A triplex bead-based assay that detects antibody isotype (IgG, IgM and IgA) and subclass (IgG1, IgG2, IgG3 and IgG4) responses against Nucleocapsid (N) protein, the receptor binding domain (RBD) and Spike (S) protein of SARS-CoV-2 was developed. After establishing baseline levels with pre-pandemic control sera (n = 113), samples from PCR-confirmed COVID-19 patients with mild-moderate disease (n = 189) collected up to 8 months post-infection were examined. The relationship between antigen-specific antibodies and neutralising antibodies (NAbs) was explored with a surrogate neutralisation assay that quantifies inhibition of the RBD/hACE-2 interaction. RESULTS: While most individuals had broad isotype and subclass responses to each antigen shortly after infection, only RBD and S protein IgG, as well as NAbs, were relatively stable over the study period, with 99%, 96% and 90% of samples, respectively, having responses over baseline 4-8 months post-infection. Anti-RBD antibodies were strongly correlated with NAbs at all time points (Pearson's r ≥ 0.87), and feasibility of using finger prick sampling to accurately measure anti-RBD IgG was demonstrated. CONCLUSION: Antibodies to SARS-CoV-2 persist for up to 8 months following mild-to-moderate infection. This robust response can be attributed to the initial exposure without immune boosting given the lack of community transmission in our setting.
ABSTRACT
BACKGROUND: The efficacy of interleukin-6 receptor antagonists in critically ill patients with coronavirus disease 2019 (Covid-19) is unclear. METHODS: We evaluated tocilizumab and sarilumab in an ongoing international, multifactorial, adaptive platform trial. Adult patients with Covid-19, within 24 hours after starting organ support in the intensive care unit (ICU), were randomly assigned to receive tocilizumab (8 mg per kilogram of body weight), sarilumab (400 mg), or standard care (control). The primary outcome was respiratory and cardiovascular organ support-free days, on an ordinal scale combining in-hospital death (assigned a value of -1) and days free of organ support to day 21. The trial uses a Bayesian statistical model with predefined criteria for superiority, efficacy, equivalence, or futility. An odds ratio greater than 1 represented improved survival, more organ support-free days, or both. RESULTS: Both tocilizumab and sarilumab met the predefined criteria for efficacy. At that time, 353 patients had been assigned to tocilizumab, 48 to sarilumab, and 402 to control. The median number of organ support-free days was 10 (interquartile range, -1 to 16) in the tocilizumab group, 11 (interquartile range, 0 to 16) in the sarilumab group, and 0 (interquartile range, -1 to 15) in the control group. The median adjusted cumulative odds ratios were 1.64 (95% credible interval, 1.25 to 2.14) for tocilizumab and 1.76 (95% credible interval, 1.17 to 2.91) for sarilumab as compared with control, yielding posterior probabilities of superiority to control of more than 99.9% and of 99.5%, respectively. An analysis of 90-day survival showed improved survival in the pooled interleukin-6 receptor antagonist groups, yielding a hazard ratio for the comparison with the control group of 1.61 (95% credible interval, 1.25 to 2.08) and a posterior probability of superiority of more than 99.9%. All secondary analyses supported efficacy of these interleukin-6 receptor antagonists. CONCLUSIONS: In critically ill patients with Covid-19 receiving organ support in ICUs, treatment with the interleukin-6 receptor antagonists tocilizumab and sarilumab improved outcomes, including survival. (REMAP-CAP ClinicalTrials.gov number, NCT02735707.).
Subject(s)
Antibodies, Monoclonal, Humanized/therapeutic use , COVID-19 Drug Treatment , Receptors, Interleukin-6/antagonists & inhibitors , Adult , Aged , Antibodies, Monoclonal, Humanized/adverse effects , COVID-19/complications , COVID-19/mortality , COVID-19/therapy , Critical Illness , Female , Hospital Mortality , Humans , Intensive Care Units , Male , Middle Aged , Odds Ratio , Respiration, ArtificialSubject(s)
COVID-19 Serological Testing , COVID-19 , Neutralization Tests , SARS-CoV-2 , COVID-19/diagnosis , COVID-19/epidemiology , COVID-19/immunology , COVID-19/virology , COVID-19 Serological Testing/methods , COVID-19 Serological Testing/standards , Clinical Laboratory Techniques/methods , Clinical Laboratory Techniques/standards , Comparative Effectiveness Research , Humans , Neutralization Tests/methods , Neutralization Tests/standards , New Zealand/epidemiology , Predictive Value of Tests , Reagent Kits, Diagnostic/classification , SARS-CoV-2/immunology , SARS-CoV-2/isolation & purification , Sensitivity and SpecificityABSTRACT
BACKGROUND: Serological assays that detect antibodies to SARS-CoV-2 are critical for determining past infection and investigating immune responses in the COVID-19 pandemic. We established ELISA-based immunoassays using locally produced antigens when New Zealand went into a nationwide lockdown and the supply chain of diagnostic reagents was a widely held domestic concern. The relationship between serum antibody binding measured by ELISA and neutralising capacity was investigated using a surrogate viral neutralisation test (sVNT). METHODS: A pre-pandemic sera panel (n = 113), including respiratory infections with symptom overlap with COVID-19, was used to establish assay specificity. Sera from PCRconfirmed SARS-CoV-2 patients (n = 21), and PCR-negative patients with respiratory symptoms suggestive of COVID-19 (n = 82) that presented to the two largest hospitals in Auckland during the lockdown period were included. A two-step IgG ELISA based on the receptor binding domain (RBD) and spike protein was adapted to determine seropositivity, and neutralising antibodies that block the RBD/hACE2 interaction were quantified by sVNT. RESULTS: The calculated cut-off (>0.2) in the two-step ELISA maximised specificity by classifying all pre-pandemic samples as negative. Sera from all PCR-confirmed COVID-19 patients were classified as seropositive by ELISA ≥7 days after symptom onset. There was 100% concordance between the two-step ELISA and the sVNT with all 7+ day sera from PCRconfirmed COVID-19 patients also classified as positive with respect to neutralising antibodies. Of the symptomatic PCR-negative cohort, one individual with notable travel history was classified as positive by two-step ELISA and sVNT, demonstrating the value of serology in detecting prior infection. CONCLUSIONS: These serological assays were established and assessed at a time when human activity was severely restricted in New Zealand. This was achieved by generous sharing of reagents and technical expertise by the international scientific community, and highly collaborative efforts of scientists and clinicians across the country. The assays have immediate utility in supporting clinical diagnostics, understanding transmission in high-risk cohorts and underpinning longerterm 'exit' strategies based on effective vaccines and therapeutics.
ABSTRACT
OBJECTIVES: To determine if lopinavir/ritonavir +/- hydroxychloroquine will reduce the proportion of participants who survive without requiring ventilatory support, 15 days after enrolment, in adult participants with non-critically ill SARS-CoV-2 infection. TRIAL DESIGN: ASCOT is an investigator-initiated, multi-centre, open-label, randomised controlled trial. Participants will have been hospitalised with confirmed COVID-19, and will be randomised 1:1:1:1 to receive lopinavir /ritonavir, hydroxychloroquine, both or neither drug in addition to standard of care management. PARTICIPANTS: Participants will be recruited from >80 hospitals across Australia and New Zealand, representing metropolitan and regional centres in both public and private sectors. Admitted patients will be eligible if aged ≥ 18 years, have confirmed SARS-CoV-2 by nucleic acid testing in the past 12 days and are expected to remain an inpatient for at least 48 hours from the time of randomisation. Potentially eligible participants will be excluded if admitted to intensive care or requiring high level respiratory support, are currently receiving study drugs or their use is contraindicated due to allergy, drug interaction or comorbidities (including baseline QTc prolongation of 470ms for women or 480ms for men), or death is anticipated imminently. INTERVENTION AND COMPARATOR: Participants will be randomised 1:1:1:1 to: Group 1: standard of care; Group 2: lopinavir (400mg) / ritonavir (100mg) twice daily for 10 days in tablet form; Group 3: hydroxychloroquine (800mg) 4x200mg administered 12 hours apart on Day 1, followed by 400mg twice a day for 6 days; Group 4: lopinavir /ritonavir plus hydroxychloroquine. MAIN OUTCOMES: Proportion of participants alive and not having required intensive respiratory support (invasive or non-invasive ventilation) at 15 days after enrolment. A range of clinical and virological secondary outcomes will also be evaluated. RANDOMISATION: The randomisation schedule will be generated by an independent statistician. Randomisation will be stratified by site and will be in permuted blocks of variable block size. The randomised sequence allocation will only be accessible to the data management group, and site investigators will have individual participant allocation provided through a web-based trial enrolment platform. BLINDING (MASKING): This is an open-label study, with researchers assessing the laboratory outcomes blinded to treatment allocation. No unblinding procedures relating to potential adverse effects are therefore required. NUMBERS TO BE RANDOMISED (SAMPLE SIZE): We assumed that 5% of participants receiving standard of care would meet the primary outcome, aimed to evaluate whether interventions could lead to a relative risk of 0.5, assuming no interaction between intervention arms. This corresponds to a required sample size of 610 per arm, with a 5% two-sided significance level (alpha) and 80% power. The total sample size therefore is planned to be 2440. TRIAL STATUS: ASCOT protocol version 3, May 5, 2020. Recruitment opened April 4, 2020 and is ongoing, with planned completion of enrolment July 31, 2021. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ( ACTRN12620000445976 ). Prospectively registered April 6, 2020. FULL PROTOCOL: The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol.