Interleukin-6 blocking agents for treating COVID-19: a living systematic review

BACKGROUND

It has been reported that people with COVID-19 and pre-existing autoantibodies against type I interferons are likely to develop an inflammatory cytokine storm responsible for severe respiratory symptoms. Since interleukin 6 (IL-6) is one of the cytokines released during this inflammatory process, IL-6 blocking agents have been used for treating people with severe COVID-19.

OBJECTIVES

To update the evidence on the effectiveness and safety of IL-6 blocking agents compared to standard care alone or to a placebo for people with COVID-19.

SEARCH METHODS

We searched the World Health Organization (WHO) International Clinical Trials Registry Platform, the Living OVerview of Evidence (L·OVE) platform, and the Cochrane COVID-19 Study Register to identify studies on 7 June 2022.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) evaluating IL-6 blocking agents compared to standard care alone or to placebo for people with COVID-19, regardless of disease severity.

DATA COLLECTION AND ANALYSIS

Pairs of researchers independently conducted study selection, extracted data and assessed risk of bias. We assessed the certainty of evidence using the GRADE approach for all critical and important outcomes. In this update we amended our protocol to update the methods used for grading evidence by establishing minimal important differences for the critical outcomes.

MAIN RESULTS

This update includes 22 additional trials, for a total of 32 trials including 12,160 randomized participants all hospitalized for COVID-19 disease. We identified a further 17 registered RCTs evaluating IL-6 blocking agents without results available as of 7 June 2022.  The mean age range varied from 56 to 75 years; 66.2% (8051/12,160) of enrolled participants were men. One-third (11/32) of included trials were placebo-controlled. Twenty-two were published in peer-reviewed journals, three were reported as preprints, two trials had results posted only on registries, and results from five trials were retrieved from another meta-analysis. Eight were funded by pharmaceutical companies.  Twenty-six included studies were multicenter trials; four were multinational and 22 took place in single countries. Recruitment of participants occurred between February 2020 and June 2021, with a mean enrollment duration of 21 weeks (range 1 to 54 weeks). Nineteen trials (60%) had a follow-up of 60 days or more. Disease severity ranged from mild to critical disease. The proportion of participants who were intubated at study inclusion also varied from 5% to 95%. Only six trials reported vaccination status; there were no vaccinated participants included in these trials, and 17 trials were conducted before vaccination was rolled out. We assessed a total of six treatments, each compared to placebo or standard care. Twenty trials assessed tocilizumab, nine assessed sarilumab, and two assessed clazakizumab. Only one trial was included for each of the other IL-6 blocking agents (siltuximab, olokizumab, and levilimab). Two trials assessed more than one treatment. Efficacy and safety of tocilizumab and sarilumab compared to standard care or placebo for treating COVID-19 At day (D) 28, tocilizumab and sarilumab probably result in little or no increase in clinical improvement (tocilizumab: risk ratio (RR) 1.05, 95% confidence interval (CI) 1.00 to 1.11; 15 RCTs, 6116 participants; moderate-certainty evidence; sarilumab: RR 0.99, 95% CI 0.94 to 1.05; 7 RCTs, 2425 participants; moderate-certainty evidence). For clinical improvement at ≥ D60, the certainty of evidence is very low for both tocilizumab (RR 1.10, 95% CI 0.81 to 1.48; 1 RCT, 97 participants; very low-certainty evidence) and sarilumab (RR 1.22, 95% CI 0.91 to 1.63; 2 RCTs, 239 participants; very low-certainty evidence). The effect of tocilizumab on the proportion of participants with a WHO Clinical Progression Score (WHO-CPS) of level 7 or above remains uncertain at D28 (RR 0.90, 95% CI 0.72 to 1.12; 13 RCTs, 2117 participants; low-certainty evidence) and that for sarilumab very uncertain (RR 1.10, 95% CI 0.90 to 1.33; 5 RCTs, 886 participants; very low-certainty evidence). Tocilizumab reduces all cause-mortality at D28 compared to standard care/placebo (RR 0.88, 95% CI 0.81 to 0.94; 18 RCTs, 7428 participants; high-certainty evidence). The evidence about the effect of sarilumab on this outcome is very uncertain (RR 1.06, 95% CI 0.86 to 1.30; 9 RCTs, 3305 participants; very low-certainty evidence). The evidence is uncertain for all cause-mortality at ≥ D60 for tocilizumab (RR 0.91, 95% CI 0.80 to 1.04; 9 RCTs, 2775 participants; low-certainty evidence) and very uncertain for sarilumab (RR 0.95, 95% CI 0.84 to 1.07; 6 RCTs, 3379 participants; very low-certainty evidence). Tocilizumab probably results in little to no difference in the risk of adverse events (RR 1.03, 95% CI 0.95 to 1.12; 9 RCTs, 1811 participants; moderate-certainty evidence). The evidence about adverse events for sarilumab is uncertain (RR 1.12, 95% CI 0.97 to 1.28; 4 RCT, 860 participants; low-certainty evidence).  The evidence about serious adverse events is very uncertain for tocilizumab (RR 0.93, 95% CI 0.81 to 1.07; 16 RCTs; 2974 participants; very low-certainty evidence) and uncertain for sarilumab (RR 1.09, 95% CI 0.97 to 1.21; 6 RCTs; 2936 participants; low-certainty evidence). Efficacy and safety of clazakizumab, olokizumab, siltuximab and levilimab compared to standard care or placebo for treating COVID-19 The evidence about the effects of clazakizumab, olokizumab, siltuximab, and levilimab comes from only one or two studies for each blocking agent, and is uncertain or very uncertain.

AUTHORS' CONCLUSIONS

In hospitalized people with COVID-19, results show a beneficial effect of tocilizumab on all-cause mortality in the short term and probably little or no difference in the risk of adverse events compared to standard care alone or placebo. Nevertheless, both tocilizumab and sarilumab probably result in little or no increase in clinical improvement at D28. Evidence for an effect of sarilumab and the other IL-6 blocking agents on critical outcomes is uncertain or very uncertain. Most of the trials included in our review were done before the waves of different variants of concern and before vaccination was rolled out on a large scale. An additional 17 RCTs of IL-6 blocking agents are currently registered with no results yet reported. The number of pending studies and the number of participants planned is low. Consequently, we will not publish further updates of this review.

Efficacy and safety of COVID-19 vaccines

BACKGROUND

Different forms of vaccines have been developed to prevent the SARS-CoV-2 virus and subsequent COVID-19 disease. Several are in widespread use globally.  OBJECTIVES: To assess the efficacy and safety of COVID-19 vaccines (as a full primary vaccination series or a booster dose) against SARS-CoV-2.

SEARCH METHODS

We searched the Cochrane COVID-19 Study Register and the COVID-19 L·OVE platform (last search date 5 November 2021). We also searched the WHO International Clinical Trials Registry Platform, regulatory agency websites, and Retraction Watch.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) comparing COVID-19 vaccines to placebo, no vaccine, other active vaccines, or other vaccine schedules.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. We used GRADE to assess the certainty of evidence for all except immunogenicity outcomes.  We synthesized data for each vaccine separately and presented summary effect estimates with 95% confidence intervals (CIs).  MAIN RESULTS: We included and analyzed 41 RCTs assessing 12 different vaccines, including homologous and heterologous vaccine schedules and the effect of booster doses. Thirty-two RCTs were multicentre and five were multinational. The sample sizes of RCTs were 60 to 44,325 participants. Participants were aged: 18 years or older in 36 RCTs; 12 years or older in one RCT; 12 to 17 years in two RCTs; and three to 17 years in two RCTs. Twenty-nine RCTs provided results for individuals aged over 60 years, and three RCTs included immunocompromized patients. No trials included pregnant women. Sixteen RCTs had two-month follow-up or less, 20 RCTs had two to six months, and five RCTs had greater than six to 12 months or less. Eighteen reports were based on preplanned interim analyses. Overall risk of bias was low for all outcomes in eight RCTs, while 33 had concerns for at least one outcome. We identified 343 registered RCTs with results not yet available.  This abstract reports results for the critical outcomes of confirmed symptomatic COVID-19, severe and critical COVID-19, and serious adverse events only for the 10 WHO-approved vaccines. For remaining outcomes and vaccines, see main text. The evidence for mortality was generally sparse and of low or very low certainty for all WHO-approved vaccines, except AD26.COV2.S (Janssen), which probably reduces the risk of all-cause mortality (risk ratio (RR) 0.25, 95% CI 0.09 to 0.67; 1 RCT, 43,783 participants; high-certainty evidence). Confirmed symptomatic COVID-19 High-certainty evidence found that BNT162b2 (BioNtech/Fosun Pharma/Pfizer), mRNA-1273 (ModernaTx), ChAdOx1 (Oxford/AstraZeneca), Ad26.COV2.S, BBIBP-CorV (Sinopharm-Beijing), and BBV152 (Bharat Biotect) reduce the incidence of symptomatic COVID-19 compared to placebo (vaccine efficacy (VE): BNT162b2: 97.84%, 95% CI 44.25% to 99.92%; 2 RCTs, 44,077 participants; mRNA-1273: 93.20%, 95% CI 91.06% to 94.83%; 2 RCTs, 31,632 participants; ChAdOx1: 70.23%, 95% CI 62.10% to 76.62%; 2 RCTs, 43,390 participants; Ad26.COV2.S: 66.90%, 95% CI 59.10% to 73.40%; 1 RCT, 39,058 participants; BBIBP-CorV: 78.10%, 95% CI 64.80% to 86.30%; 1 RCT, 25,463 participants; BBV152: 77.80%, 95% CI 65.20% to 86.40%; 1 RCT, 16,973 participants). Moderate-certainty evidence found that NVX-CoV2373 (Novavax) probably reduces the incidence of symptomatic COVID-19 compared to placebo (VE 82.91%, 95% CI 50.49% to 94.10%; 3 RCTs, 42,175 participants). There is low-certainty evidence for CoronaVac (Sinovac) for this outcome (VE 69.81%, 95% CI 12.27% to 89.61%; 2 RCTs, 19,852 participants). Severe or critical COVID-19 High-certainty evidence found that BNT162b2, mRNA-1273, Ad26.COV2.S, and BBV152 result in a large reduction in incidence of severe or critical disease due to COVID-19 compared to placebo (VE: BNT162b2: 95.70%, 95% CI 73.90% to 99.90%; 1 RCT, 46,077 participants; mRNA-1273: 98.20%, 95% CI 92.80% to 99.60%; 1 RCT, 28,451 participants; AD26.COV2.S: 76.30%, 95% CI 57.90% to 87.50%; 1 RCT, 39,058 participants; BBV152: 93.40%, 95% CI 57.10% to 99.80%; 1 RCT, 16,976 participants). Moderate-certainty evidence found that NVX-CoV2373 probably reduces the incidence of severe or critical COVID-19 (VE 100.00%, 95% CI 86.99% to 100.00%; 1 RCT, 25,452 participants). Two trials reported high efficacy of CoronaVac for severe or critical disease with wide CIs, but these results could not be pooled. Serious adverse events (SAEs) mRNA-1273, ChAdOx1 (Oxford-AstraZeneca)/SII-ChAdOx1 (Serum Institute of India), Ad26.COV2.S, and BBV152 probably result in little or no difference in SAEs compared to placebo (RR: mRNA-1273: 0.92, 95% CI 0.78 to 1.08; 2 RCTs, 34,072 participants; ChAdOx1/SII-ChAdOx1: 0.88, 95% CI 0.72 to 1.07; 7 RCTs, 58,182 participants; Ad26.COV2.S: 0.92, 95% CI 0.69 to 1.22; 1 RCT, 43,783 participants); BBV152: 0.65, 95% CI 0.43 to 0.97; 1 RCT, 25,928 participants). In each of these, the likely absolute difference in effects was fewer than 5/1000 participants. Evidence for SAEs is uncertain for BNT162b2, CoronaVac, BBIBP-CorV, and NVX-CoV2373 compared to placebo (RR: BNT162b2: 1.30, 95% CI 0.55 to 3.07; 2 RCTs, 46,107 participants; CoronaVac: 0.97, 95% CI 0.62 to 1.51; 4 RCTs, 23,139 participants; BBIBP-CorV: 0.76, 95% CI 0.54 to 1.06; 1 RCT, 26,924 participants; NVX-CoV2373: 0.92, 95% CI 0.74 to 1.14; 4 RCTs, 38,802 participants). For the evaluation of heterologous schedules, booster doses, and efficacy against variants of concern, see main text of review.

AUTHORS' CONCLUSIONS

Compared to placebo, most vaccines reduce, or likely reduce, the proportion of participants with confirmed symptomatic COVID-19, and for some, there is high-certainty evidence that they reduce severe or critical disease. There is probably little or no difference between most vaccines and placebo for serious adverse events. Over 300 registered RCTs are evaluating the efficacy of COVID-19 vaccines, and this review is updated regularly on the COVID-NMA platform (covid-nma.com). Implications for practice Due to the trial exclusions, these results cannot be generalized to pregnant women, individuals with a history of SARS-CoV-2 infection, or immunocompromized people. Most trials had a short follow-up and were conducted before the emergence of variants of concern. Implications for research Future research should evaluate the long-term effect of vaccines, compare different vaccines and vaccine schedules, assess vaccine efficacy and safety in specific populations, and include outcomes such as preventing long COVID-19. Ongoing evaluation of vaccine efficacy and effectiveness against emerging variants of concern is also vital.

Toward an observatory of the evolution of clinical trials through phylomemy reconstruction: the COVID-19 vaccines example

Objectives

To visualize the evolution of all registered COVID-19 vaccine trials.

Study Design and Setting

As part of the living mapping of the COVID-NMA initiative, we identify biweekly all COVID-19 vaccine trials and automatically extract data from the EU clinical trials registry, ClinicalTrials.gov, IRCT and the World Health Organization International Clinical Trials Registry Platform. Data are curated and enriched by epidemiologists. We have used the phylomemy reconstruction process to visualize the temporal evolution of COVID-19 vaccines trials descriptions. We have analyzed the textual contents of 1,794 trials descriptions (last search in October 2021) and explored their collective structure along with their semantic dynamics.

Results

The structures highlighted by the phylomemy reconstruction processes synthesize the complexity of the knowledge produced by the research community. The reconstructed phylomemy clearly retrieves the five major COVID-19 vaccine platforms in the form of complete branches. The branches interactions reflect the exploration of a new approach to vaccine implementation moving from homologous prime vaccination to heterologous prime vaccination. Phylomemies also clearly identifies shifts in research questions, from vaccine efficacy to booster efficacy.

Conclusion

This new method provides important insights for the global coordination between research teams especially in crisis situations such as the COVID-19 pandemic.

Interleukin-1 blocking agents for treating COVID-19

BACKGROUND

Interleukin-1 (IL-1) blocking agents have been used for treating severe coronavirus disease 2019 (COVID-19), on the premise that their immunomodulatory effect might be beneficial in people with COVID-19.

OBJECTIVES

To assess the effects of IL-1 blocking agents compared with standard care alone or with placebo on effectiveness and safety outcomes in people with COVID-19. We will update this assessment regularly.

SEARCH METHODS

We searched the Cochrane COVID-19 Study Register and the COVID-19 L-OVE Platform (search date 5 November 2021). These sources are maintained through regular searches of MEDLINE, Embase, CENTRAL, trial registers and other sources. We also checked the World Health Organization International Clinical Trials Registry Platform, regulatory agency websites, Retraction Watch (search date 3 November 2021).

SELECTION CRITERIA

We included randomised controlled trials (RCTs) evaluating IL-1 blocking agents compared with standard care alone or with placebo for people with COVID-19, regardless of disease severity.

DATA COLLECTION AND ANALYSIS

We followed Cochrane methodology. The protocol was amended to reduce the number of outcomes considered. Two researchers independently screened and extracted data and assessed the risk of bias with the Cochrane Risk of Bias 2 tool. We rated the certainty of evidence using the GRADE approach for the critical outcomes of clinical improvement (Day 28; ≥ D60); WHO Clinical Progression Score of level 7 or above (i.e. the proportion of participants with mechanical ventilation +/- additional organ support OR death) (D28; ≥ D60); all-cause mortality (D28; ≥ D60); incidence of any adverse events; and incidence of serious adverse events.

MAIN RESULTS

We identified four RCTs of anakinra (three published in peer-reviewed journals, one reported as a preprint) and two RCTs of canakinumab (published in peer-reviewed journals). All trials were multicentre (2 to 133 centres). Two trials stopped early (one due to futility and one as the trigger for inferiority was met). The median/mean age range varied from 58 to 68 years; the proportion of men varied from 58% to 77%. All participants were hospitalised; 67% to 100% were on oxygen at baseline but not intubated; between 0% and 33% were intubated at baseline. We identified a further 16 registered trials with no results available, of which 15 assessed anakinra (four completed, four terminated, five ongoing, three not recruiting) and one (completed) trial assessed canakinumab. Effectiveness of anakinra for people with COVID-19 Anakinra probably results in little or no increase in clinical improvement at D28 (risk ratio (RR) 1.08, 95% confidence interval (CI) 0.97 to 1.20; 3 RCTs, 837 participants; absolute effect: 59 more per 1000 (from 22 fewer to 147 more); moderate-certainty evidence. The evidence is uncertain about an effect of anakinra on 1) the proportion of participants with a WHO Clinical Progression Score of level 7 or above at D28 (RR 0.67, 95% CI 0.36 to 1.22; 2 RCTs, 722 participants; absolute effect: 55 fewer per 1000 (from 107 fewer to 37 more); low-certainty evidence) and ≥ D60 (RR 0.54, 95% CI 0.30 to 0.96; 1 RCT, 606 participants; absolute effect: 47 fewer per 1000 (from 72 fewer to 4 fewer) low-certainty evidence); and 2) all-cause mortality at D28 (RR 0.69, 95% CI 0.34 to 1.39; 2 RCTs, 722 participants; absolute effect: 32 fewer per 1000 (from 68 fewer to 40 more); low-certainty evidence).  The evidence is very uncertain about an effect of anakinra on 1) the proportion of participants with clinical improvement at ≥ D60 (RR 0.93, 95% CI 0.78 to 1.12; 1 RCT, 115 participants; absolute effect: 59 fewer per 1000 (from 186 fewer to 102 more); very low-certainty evidence); and 2) all-cause mortality at ≥ D60 (RR 1.03, 95% CI 0.68 to 1.56; 4 RCTs, 1633 participants; absolute effect: 8 more per 1000 (from 84 fewer to 147 more); very low-certainty evidence). Safety of anakinra for people with COVID-19 Anakinra probably results in little or no increase in adverse events (RR 1.02, 95% CI 0.94 to 1.11; 2 RCTs, 722 participants; absolute effect: 14 more per 1000 (from 43 fewer to 78 more); moderate-certainty evidence).  The evidence is uncertain regarding an effect of anakinra on serious adverse events (RR 0.95, 95% CI 0.58 to 1.56; 2 RCTs, 722 participants; absolute effect: 12 fewer per 1000 (from 104 fewer to 138 more); low-certainty evidence). Effectiveness of canakinumab for people with COVID-19 Canakinumab probably results in little or no increase in clinical improvement at D28 (RR 1.05, 95% CI 0.96 to 1.14; 2 RCTs, 499 participants; absolute effect: 42 more per 1000 (from 33 fewer to 116 more); moderate-certainty evidence).  The evidence of an effect of canakinumab is uncertain on 1) the proportion of participants with a WHO Clinical Progression Score of level 7 or above at D28 (RR 0.72, 95% CI 0.44 to 1.20; 2 RCTs, 499 participants; absolute effect: 35 fewer per 1000 (from 69 fewer to 25 more); low-certainty evidence); and 2) all-cause mortality at D28 (RR:0.75; 95% CI 0.39 to 1.42); 2 RCTs, 499 participants; absolute effect: 20 fewer per 1000 (from 48 fewer to 33 more); low-certainty evidence).  The evidence is very uncertain about an effect of canakinumab on all-cause mortality at ≥ D60 (RR 0.55, 95% CI 0.16 to 1.91; 1 RCT, 45 participants; absolute effect: 112 fewer per 1000 (from 210 fewer to 227 more); very low-certainty evidence). Safety of canakinumab for people with COVID-19 Canakinumab probably results in little or no increase in adverse events (RR 1.02; 95% CI 0.86 to 1.21; 1 RCT, 454 participants; absolute effect: 11 more per 1000 (from 74 fewer to 111 more); moderate-certainty evidence). The evidence of an effect of canakinumab on serious adverse events is uncertain (RR 0.80, 95% CI 0.57 to 1.13; 2 RCTs, 499 participants; absolute effect: 44 fewer per 1000 (from 94 fewer to 28 more); low-certainty evidence).

AUTHORS' CONCLUSIONS

Overall, we did not find evidence for an important beneficial effect of IL-1 blocking agents. The evidence is uncertain or very uncertain for several outcomes. Sixteen trials of anakinra and canakinumab with no results are currently registered, of which four are completed, and four terminated. The findings of this review are updated on the COVID-NMA platform (covid-nma.com).

Interleukin-6 blocking agents for treating COVID-19: a living systematic review

BACKGROUND

Interleukin 6 (IL-6) blocking agents have been used for treating severe coronavirus disease 2019 (COVID-19). Their immunosuppressive effect might be valuable in patients with COVID-19 characterised by substantial immune system dysfunction by controlling inflammation and promoting disease tolerance.

OBJECTIVES

To assess the effect of IL-6 blocking agents compared to standard care alone or with placebo on efficacy and safety outcomes in COVID-19. We will update this assessment regularly.

SEARCH METHODS

We searched the World Health Organization (WHO) International Clinical Trials Registry Platform (up to 11 February 2021) and the L-OVE platform, and Cochrane COVID-19 Study Register to identify trials up to 26 February 2021.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) evaluating IL-6 blocking agents compared with standard care alone or with placebo for people with COVID-19, regardless of disease severity.

DATA COLLECTION AND ANALYSIS

We followed standard Cochrane methodology. The protocol was amended to reduce the number of outcomes considered. Two review authors independently collected data and assessed the risk of bias with the Cochrane Risk of Bias 2 tool. We rated the certainty of evidence with the GRADE approach for the critical outcomes such as clinical improvement (defined as hospital discharge or improvement on the scale used by trialists to evaluate clinical progression or recovery) (day (D) 28 / ≥ D60); WHO Clinical Progression Score of level 7 or above (i.e. the proportion of participants with mechanical ventilation +/- additional organ support OR death) (D28 / ≥ D60); all-cause mortality (D28 / ≥ D60); incidence of any adverse events; and incidence of serious adverse events.

MAIN RESULTS

We identified 10 RCTs with available data including one platform trial comparing tocilizumab and sarilumab with standard of care. These trials evaluated tocilizumab (nine RCTs including two platform trials; seven were reported as peer-reviewed articles, two as preprints; 6428 randomised participants); and two sarilumab (one platform trial reported as peer reviewed article, one reported as preprint, 880 randomised participants). All trials included were multicentre trials. They were conducted in Brazil, China, France, Italy, UK, USA, and four were multi-country trials. The mean age range of participants ranged from 56 to 65 years; 4572 (66.3%) of trial participants were male. Disease severity ranged from mild to critical disease. The reported proportion of participants on oxygen at baseline but not intubated varied from 56% to 100% where reported. Five trials reported the inclusion of intubated patients at baseline. We identified a further 20 registered RCTs of tocilizumab compared to placebo/standard care (five completed without available results, five terminated without available results, eight ongoing, two not recruiting); 11 RCTs of sarilumab (two completed without results, three terminated without available results, six ongoing); six RCTs of clazakisumab (five ongoing, one not recruiting); two RCTs of olokizumab (one completed, one not recruiting); one of siltuximab (ongoing) and one RCT of levilimab (completed without available results). Of note, three were cancelled (2 tocilizumab, 1 clazakisumab). One multiple-arm RCT evaluated both tocilizumab and sarilumab compared to standard of care, one three-arm RCT evaluated tocilizumab and siltuximab compared to standard of care and consequently they appear in each respective comparison. Tocilizumab versus standard care alone or with placebo a. Effectiveness of tocilizumab for patients with COVID-19 Tocilizumab probably results in little or no increase in the outcome of clinical improvement at D28 (RR 1.06, 95% CI 1.00 to 1.13; I² = 40.9%; 7 RCTs, 5585 participants; absolute effect: 31 more with clinical improvement per 1000 (from 0 fewer to 67 more); moderate-certainty evidence). However, we cannot exclude that some subgroups of patients could benefit from the treatment. We did not obtain data for longer-term follow-up (≥ D60). The effect of tocilizumab on the proportion of participants with a WHO Clinical Progression Score of level of 7 or above is uncertain at D28 (RR 0.99, 95% CI 0.56 to 1.74; I² = 64.4%; 3 RCTs, 712 participants; low-certainty evidence). We did not obtain data for longer-term follow-up (≥ D60). Tocilizumab reduces all-cause mortality at D28 compared to standard care alone or placebo (RR 0.89, 95% CI 0.82 to 0.97; I² = 0.0%; 8 RCTs, 6363 participants; absolute effect: 32 fewer deaths per 1000 (from 52 fewer to 9 fewer); high-certainty evidence). The evidence suggests uncertainty around the effect on mortality at ≥ D60 (RR 0.86, 95% CI 0.53 to 1.40; I² = 0.0%; 2 RCTs, 519 participants; low-certainty evidence). b. Safety of tocilizumab for patients with COVID-19 The evidence is very uncertain about the effect of tocilizumab on adverse events (RR 1.23, 95% CI 0.87 to 1.72; I² = 86.4%; 7 RCTs, 1534 participants; very low-certainty evidence). Nevertheless, tocilizumab probably results in slightly fewer serious adverse events than standard care alone or placebo (RR 0.89, 95% CI 0.75 to 1.06; I² = 0.0%; 8 RCTs, 2312 participants; moderate-certainty evidence). Sarilumab versus standard care alone or with placebo The evidence is uncertain about the effect of sarilumab on all-cause mortality at D28 (RR 0.77, 95% CI 0.43 to 1.36; 2 RCTs, 880 participants; low certainty), on all-cause mortality at ≥ D60 (RR 1.00, 95% CI 0.50 to 2.0; 1 RCT, 420 participants; low certainty), and serious adverse events (RR 1.17, 95% CI 0.77 to 1.77; 2 RCTs, 880 participants; low certainty). It is unlikely that sarilumab results in an important increase of adverse events (RR 1.05, 95% CI 0.88 to 1.25; 1 RCT, 420 participants; moderate certainty). However, an increase cannot be excluded No data were available for other critical outcomes.

AUTHORS' CONCLUSIONS

On average, tocilizumab reduces all-cause mortality at D28 compared to standard care alone or placebo and probably results in slightly fewer serious adverse events than standard care alone or placebo. Nevertheless, tocilizumab probably results in little or no increase in the outcome clinical improvement (defined as hospital discharge or improvement measured by trialist-defined scales) at D28. The impact of tocilizumab on other outcomes is uncertain or very uncertain. With the data available, we were not able to explore heterogeneity. Individual patient data meta-analyses are needed to be able to identify which patients are more likely to benefit from this treatment. Evidence for an effect of sarilumab is uncertain and evidence for other anti-IL6 agents is unavailable. Thirty-nine RCTs of IL-6 blocking agents with no results are currently registered, of which nine are completed and seven trials were terminated with no results available. The findings of this review will be updated as new data are made available on the COVID-NMA platform (covid-nma.com).

Research response to coronavirus disease 2019 needed better coordination and collaboration: a living mapping of registered trials

Objectives

Researchers worldwide are actively engaging in research activities to search for preventive and therapeutic interventions against coronavirus disease 2019 (COVID-19). Our aim was to describe the planning of randomized controlled trials (RCTs) in terms of timing related to the course of the COVID-19 epidemic and research question evaluated.

Study Design and Setting

We performed a living mapping of RCTs registered in the WHO International Clinical Trials Registry Platform. We systematically search the platform every week for all RCTs evaluating preventive interventions and treatments for COVID-19 and created a publicly available interactive mapping tool at https://covid-nma.com to visualize all trials registered.

Results

By August 12, 2020, 1,568 trials for COVID-19 were registered worldwide. Overall, the median ([Q1–Q3]; range) delay between the first case recorded in each country and the first RCT registered was 47 days ([33–67]; 15–163). For the 9 countries with the highest number of trials registered, most trials were registered after the peak of the epidemic (from 100% trials in Italy to 38% in the United States). Most trials evaluated treatments (1,333 trials; 85%); only 223 (14%) evaluated preventive strategies and 12 postacute period intervention. A total of 254 trials were planned to assess different regimens of hydroxychloroquine with an expected sample size of 110,883 patients.

Conclusion

This living mapping analysis showed that COVID-19 trials have relatively small sample size with certain redundancy in research questions. Most trials were registered when the first peak of the pandemic has passed.

Parallel-transmission-enabled magnetization-prepared rapid gradient-echo T1-weighted imaging of the human brain at 7 T

One of the promises of Ultra High Field (UHF) MRI scanners is to bring finer spatial resolution in the human brain images due to an increased signal to noise ratio. However, at such field strengths, the spatial non-uniformity of the Radio Frequency (RF) transmit profiles challenges the applicability of most MRI sequences, where the signal and contrast levels strongly depend on the flip angle (FA) homogeneity. In particular, the MP-RAGE sequence, one of the most commonly employed 3D sequences to obtain T1-weighted anatomical images of the brain, is highly sensitive to these spatial variations. These cause deterioration in image quality and complicate subsequent image post-processing such as automated tissue segmentation at UHF. In this work, we evaluate the potential of parallel-transmission (pTx) to obtain high-quality MP-RAGE images of the human brain at 7 T. To this end, non-selective transmit-SENSE pulses were individually tailored for each of 8 subjects under study, and applied to an 8-channel transmit-array. Such RF pulses were designed both for the low-FA excitation train and the 180° inversion preparation involved in the sequence, both utilizing the recently introduced k(T)-point trajectory. The resulting images were compared with those obtained from the conventional method and from subject-specific RF-shimmed excitations. In addition, four of the volunteers were scanned at 3 T for benchmarking purposes (clinical setup without pTx). Subsequently, automated tissue classification was performed to provide a more quantitative measure of the final image quality. Results indicated that pTx could already significantly improve image quality at 7 T by adopting a suitable RF-Shim. Exploiting the full potential of the pTx-setup, the proposed k(T)-point method provided excellent inversion fidelity, comparable to what is commonly only achievable at 3 T with energy intensive adiabatic pulses. Furthermore, the cumulative energy deposition was simultaneously reduced by over 40% compared to the conventional adiabatic inversions. Regarding the low-FA k(T)-point based excitations, the FA uniformity achieved at 7 T surpassed what is typically obtained at 3 T. Subsequently, automated white and gray matter segmentation not only confirmed the expected improvements in image quality, but also suggests that care should be taken to properly account for the strong local susceptibility effects near cranial cavities. Overall, these findings indicate that the k(T)-point-based pTx solution is an excellent candidate for UHF 3D imaging, where patient safety is a major concern due to the increase of specific absorption rates.

kT -points: short three-dimensional tailored RF pulses for flip-angle homogenization over an extended volume

With Transmit SENSE, we demonstrate the feasibility of uniformly exciting a volume such as the human brain at 7T through the use of an original minimalist transmit k-space coverage, referred to as "k(T) -points." Radio-frequency energy is deposited only at a limited number of k-space locations in the vicinity of the center to counteract transmit sensitivity inhomogeneities. The resulting nonselective pulses are short and need little energy compared to adiabatic or other B 1+-robust pulses available in the literature, making them good candidates for short-repetition time 3D sequences at high field. Experimental verification was performed on three human volunteers at 7T by means of an 8-channel transmit array system. On average, whereas the standard circularly polarized excitation resulted in a 33%-flip angle spread (standard deviation over mean) throughout the brain, and a static radio-frequency shim showed flip angle variations of 17% and up, application of k(T) -point-based excitations demonstrated excellent flip angle uniformity (8%) for a small target flip angle and with sub-millisecond durations.

Factors associated with upper respiratory tract disease caused by feline herpesvirus, feline calicivirus, Chlamydophila felis and Bordetella bronchiseptica in cats: experience from 218 European catteries

A full history of the management practices and the prevalence of upper respiratory tract disease (URTD) at 218 rescue shelters, breeding establishments and private households with five or more cats was recorded. Oropharyngeal and conjunctival swabs and blood samples were taken from 1748 cats. The prevalences of feline herpesvirus (FHV), feline calicivirus (FCV), Chlamydophila felis and Bordetella bronchiseptica were determined by PCR on swab samples. An ELISA was applied to determine the prevalence of antibodies to B. bronchiseptica. The rates of detection by PCR of each pathogen in the cats in catteries with and without ongoing URTD were, respectively, FHV 16 per cent and 8 per cent; FCV 47 per cent and 29 per cent; C. felis 10 per cent and 3 per cent; and B. bronchiseptica 5 per cent and 1.3 per cent; the seroprevalences of B. bronchiseptica were 61 per cent and 41 per cent, respectively. There was evidence that FHV, FCV and B. bronchiseptica played a role in URTD. The risk factors associated with the disease were less than excellent hygiene, contact with dogs with URTD, and larger numbers of cats in the cattery or household.

[Ovarian carcinomas. Intraperitoneal chemotherapy by needle]

Between January 1980 and February 1988, 61 women with ordinary ovarian carcinoma (OC) were treated with combined intraperitoneal and intravenous first-line therapy. For intraperitoneal infusions we did not use implanted systems which are often poorly tolerated and sometimes create non-negligible complications. We simply used a lumbar puncture needle left in situ for less than 2 hours. In second regard laparotomies, the 7 patients with stage I OC and the 3 patients with stage II OC were in histologically and cytologically proven complete remission, as were 34 of the 43 patients with stage III OC (79 percent) and 1 of the 8 patients with stage IV OC. After a mean follow-up of 56 months, the overall actuarial survival rate was 66 percent and the survival rate without recurrence was 54 percent. During the same period, 26 patients with recurrent OC were treated with second-line intraperitoneal chemotherapy. After a mean follow-up of 30 months, 10 were in apparently complete remission, and after a 27 to 61 months period 7 of these 10 patients had no recurrence. These results must be compared with those obtained with other salvage methods.

[Airports malaria: findings of a survey in Paris airports (author's transl)]

From 1976 to 1978, thirteen cases of malaria have been reported from France. Ten of them occurred in the vicinity of the airport Roissy-Charles de Gaulle. The entomological investigation which is described there have been performed to evaluate risk of local transmission and to plan prophylactic measures.