A comparison of the effectiveness of different doses of tocilizumab and sarilumab in the treatment of severe COVID-19: a natural experiment due to drug shortages

Objectives IL-6 inhibitors are administered to treat hospitalized COVID-19 patients. In 2021, due to shortages, different dosing regimens of tocilizumab, and a switch to sarilumab, were consecutively implemented. Using real world data, we compare the effectiveness of these IL-6 inhibitors. Methods Hospitalized COVID-19 patients, treated with IL-6 inhibitors, were included in this natural-experiment study. Sixty-day survival, hospital- and ICU length of stay and progression to ICU or death were compared between 8 mg/kg tocilizumab, fixed dose tocilizumab, low dose tocilizumab and fixed dose sarilumab treatment groups. Results 5485 patients from 49 hospitals were included. After correction for confounding, increased hazard ratios for 60-day mortality were observed for fixed dose tocilizumab (HR 1.20, 95% CI 1.04-1.39), low dose tocilizumab (HR 1.12, 95% CI 0.97-1.31) and sarilumab (HR 1.24, 95% CI 1.08-1.42), all relative to 8 mg/kg. The 8 mg/kg dosing regimen had lower odds for progression to ICU or death. Both hospital- and ICU length of stay were shorter for low dose tocilizumab than for the 8 mg/kg group. Conclusions We found differences in the probability of 60-day survival and the incidence of the combined outcome of mortality or ICU admission, mostly favoring 8 mg/kg tocilizumab. Because of potential time associated residual confounding, further clinical studies are warranted.

Bacillus Calmette-Guérin vaccine for prevention of COVID-19 and other respiratory tract infections in older adults with comorbidities: a randomized controlled trial

Objectives To test whether BCG vaccination would reduce the incidence of COVID-19 and other respiratory tract infections in older adults with one or more comorbidities. Methods Community-dwelling adults over 60 years old with one or more underlying comorbidities and no contra-indications for BCG vaccination were randomized 1:1 to BCG or placebo vaccination and followed for six months. The primary endpoint was self-reported test-confirmed COVID-19 incidence. Secondary endpoints included COVID-19 hospital admissions and clinically relevant RTI (i.e. RTI including but not limited to COVID-19 requiring medical intervention). COVID-19 and clinically relevant RTI episodes were adjudicated. Incidences were compared using Fine and Gray regression, accounting for competing events. Results A total of 6,112 participants with a median age of 69 years (inter-quartile range 65-74) and median of 2 (inter-quartile range 1-3) comorbidities were randomized to BCG (n=3,058) or placebo (n=3,054) vaccination. COVID-19 infections were reported by 129 BCG recipients compared to 115 placebo recipients (hazard ratio (HR) 1.12;95% confidence interval (CI) 0.87-1.44). COVID-19-related hospitalization occurred in 18 BCG and 21 placebo recipients (HR 0.86;95% CI 0.46-1.61). During the study period 13 BCG recipients compared to 18 placebo recipients died (HR 0.71;95% CI 0.35 - 1.43) of which 11 deaths (35%) were COVID-19 related six in the placebo group and five in the BCG group. Clinically relevant RTI was reported by 66 BCG and 72 placebo recipients (HR 0.92;95% CI 0.66-1.28). Conclusion BCG vaccination does not protect older adults with comorbidities against COVID-19, COVID-19 hospitalization or clinically relevant RTI.

A comparison of the effectiveness of different doses of tocilizumab and sarilumab in the treatment of severe COVID-19: a natural experiment due to drug shortages.

OBJECTIVES: Interleukin (IL)-6 inhibitors are administered to treat patients hospitalized with COVID-19. In 2021, due to shortages, different dosing regimens of tocilizumab, and a switch to sarilumab, were consecutively implemented. Using real-world data, we compare the effectiveness of these IL-6 inhibitors. METHODS: Hospitalized patients with COVID-19, treated with IL-6 inhibitors, were included in this natural experiment study. Sixty-day survival, hospital- and intensive care unit (ICU) length of stay, and progression to ICU or death were compared between 8 mg/kg tocilizumab, fixed-dose tocilizumab, low-dose tocilizumab, and fixed-dose sarilumab treatment groups. RESULTS: A total of 5485 patients from 49 hospitals were included. After correction for confounding, increased hazard ratios (HRs) for 60-day mortality were observed for fixed-dose tocilizumab (HR 1.20, 95% confidence interval [CI] 1.04-1.39), low-dose tocilizumab (HR 1.12, 95% CI 0.97-1.31), and sarilumab (HR 1.24, 95% CI 1.08-1.42), all relative to 8 mg/kg. The 8 mg/kg dosing regimen had lower odds of progression to ICU or death. Both hospital- and ICU length of stay were shorter for low-dose tocilizumab than for the 8 mg/kg group. CONCLUSION: We found differences in the probability of 60-day survival and the incidence of the combined outcome of mortality or ICU admission, mostly favoring 8 mg/kg tocilizumab. Because of potential time-associated residual confounding, further clinical studies are warranted.

Bacillus Calmette-Guérin vaccine for prevention of COVID-19 and other respiratory tract infections in older adults with comorbidities: a randomized controlled trial.

OBJECTIVES: To test whether Bacillus Calmette-Guérin (BCG) vaccination would reduce the incidence of COVID-19 and other respiratory tract infections (RTIs) in older adults with one or more comorbidities. METHODS: Community-dwelling adults aged 60 years or older with one or more underlying comorbidities and no contraindications to BCG vaccination were randomized 1:1 to BCG or placebo vaccination and followed for 6 months. The primary endpoint was a self-reported, test-confirmed COVID-19 incidence. Secondary endpoints included COVID-19 hospital admissions and clinically relevant RTIs (i.e. RTIs including but not limited to COVID-19 requiring medical intervention). COVID-19 and clinically relevant RTI episodes were adjudicated. Incidences were compared using Fine-Gray regression, accounting for competing events. RESULTS: A total of 6112 participants with a median age of 69 years (interquartile range, 65-74) and median of 2 (interquartile range, 1-3) comorbidities were randomized to BCG (n = 3058) or placebo (n = 3054) vaccination. COVID-19 infections were reported by 129 BCG recipients compared to 115 placebo recipients [hazard ratio (HR), 1.12; 95% CI, 0.87-1.44]. COVID-19-related hospitalization occurred in 18 BCG and 21 placebo recipients (HR, 0.86; 95% CI, 0.46-1.61). During the study period, 13 BCG recipients died compared with 18 placebo recipients (HR, 0.71; 95% CI, 0.35-1.43), of which 11 deaths (35%) were COVID-19-related: six in the placebo group and five in the BCG group. Clinically relevant RTI was reported by 66 BCG and 72 placebo recipients (HR, 0.92; 95% CI, 0.66-1.28). DISCUSSION: BCG vaccination does not protect older adults with comorbidities against COVID-19, COVID-19 hospitalization, or clinically relevant RTIs.

External validation of risk scores to predict in-hospital mortality in patients hospitalized due to coronavirus disease 2019.

BACKGROUND: The coronavirus disease 2019 (COVID-19) presents an urgent threat to global health. Prediction models that accurately estimate mortality risk in hospitalized patients could assist medical staff in treatment and allocating limited resources. AIMS: To externally validate two promising previously published risk scores that predict in-hospital mortality among hospitalized COVID-19 patients. METHODS: Two prospective cohorts were available; a cohort of 1028 patients admitted to one of nine hospitals in Lombardy, Italy (the Lombardy cohort) and a cohort of 432 patients admitted to a hospital in Leiden, the Netherlands (the Leiden cohort). The endpoint was in-hospital mortality. All patients were adult and tested COVID-19 PCR-positive. Model discrimination and calibration were assessed. RESULTS: The C-statistic of the 4C mortality score was good in the Lombardy cohort (0.85, 95CI: 0.82-0.89) and in the Leiden cohort (0.87, 95CI: 0.80-0.94). Model calibration was acceptable in the Lombardy cohort but poor in the Leiden cohort due to the model systematically overpredicting the mortality risk for all patients. The C-statistic of the CURB-65 score was good in the Lombardy cohort (0.80, 95CI: 0.75-0.85) and in the Leiden cohort (0.82, 95CI: 0.76-0.88). The mortality rate in the CURB-65 development cohort was much lower than the mortality rate in the Lombardy cohort. A similar but less pronounced trend was found for patients in the Leiden cohort. CONCLUSION: Although performances did not differ greatly, the 4C mortality score showed the best performance. However, because of quickly changing circumstances, model recalibration may be necessary before using the 4C mortality score.

Ongoing and future COVID-19 vaccine clinical trials: challenges and opportunities.

Large-scale deployment of COVID-19 vaccines will seriously affect the ongoing phases 2 and 3 randomised placebo-controlled trials assessing SARS-CoV-2 vaccine candidates. The effect will be particularly acute in high-income countries where the entire adult or older population could be vaccinated by late 2021. Regrettably, only a small proportion of the population in many low-income and middle-income countries will have access to available vaccines. Sponsors of COVID-19 vaccine candidates currently in phase 2 or initiating phase 3 trials in 2021 should consider continuing the research in countries with limited affordability and availability of COVID-19 vaccines. Several ethical principles must be implemented to ensure the equitable, non-exploitative, and respectful conduct of trials in resource-poor settings. Once sufficient knowledge on the immunogenicity response to COVID-19 vaccines is acquired, non-inferiority immunogenicity trials-comparing the immune response of a vaccine candidate to that of an authorised vaccine-would probably be the most common trial design. Until then, placebo-controlled, double-blind, crossover trials will continue to play a role in the development of new vaccine candidates. WHO or the Council for International Organizations of Medical Sciences should define an ethical framework for the requirements and benefits for trial participants and host communities in resource-poor settings that should require commitment from all vaccine candidate sponsors from high-income countries.

Hepatitis C Virus Reactivation Following COVID-19 Vaccination - A Case Report.

PURPOSE: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection impacted morbidity and mortality during the pandemic of 2020-2021. A number of anti-COVID-19 vaccines have been developed with an unprecedented speed. While these vaccines have good efficacy and are safe, the experience with their use is limited and hence the knowledge of rare side effects. Identifying rare complications is important for future safe use of these vaccines. MATERIALS AND METHODS: Here, we report a case of a 82-year old patient with dementia who was admitted to a nursing home in the Netherlands. After vaccination with COVID-19 vaccination, physical examinations and lab tests were performed. RESULTS: She had a reactivation of hepatitis C infection after vaccination with the mRNA-based Pfizer-BioNTech COVID-19 vaccine. This reactivation manifested with jaundice, loss of consciousness, hepatic coma and death. CONCLUSION: This reactivation of hepatitis C virus after vaccination with the Pfizer-BioNTech COVID­19 vaccine suggests a need for critical consideration of individuals with prior HCV infection and considered for COVID-19 vaccination.

Assessment of Risks Associated With Severe Acute Respiratory Syndrome Coronavirus 2 Experimental Human Infection Studies.

Controlled human infection (CHI) models for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been proposed as a tool to accelerate the development of vaccines and drugs. Such models carry inherent risks. Participants may develop severe disease or complications after deliberate infection. Prolonged isolation may negatively impact their well-being. Through secondary infection of study personnel or participant household contacts, the experimental virus strain may cause a community outbreak. We identified risks associated with such a SARS-CoV-2 CHI model and assessed their likelihood and impact and propose strategies that mitigate these risks. In this report, we show that risks can be minimized with proper risk mitigation strategies; the residual risk, however, should be weighed carefully against the scientific and social values of such a CHI model.

Why crowding matters in the time of COVID-19 pandemic? - a lesson from the carnival effect on the 2017/2018 influenza epidemic in the Netherlands.

BACKGROUND: To evaluate the association between crowding and transmission of viral respiratory infectious diseases, we investigated the change in transmission patterns of influenza and COVID-19 before and after a mass gathering event (i.e., carnival) in the Netherlands. METHODS: Information on individual hospitalizations related to the 2017/2018 influenza epidemic were accessed from Statistics Netherlands. The influenza cases were stratified between non-carnival and carnival regions. Distributions of influenza cases were plotted with time and compared between regions. A similar investigation in the early outbreak of COVID-19 was also conducted using open data from the Dutch National Institute for Public Health and the Environment. RESULTS: Baseline characteristics between non-carnival and carnival regions were broadly similar. There were 13,836 influenza-related hospitalizations in the 2017/2018 influenza epidemic, and carnival fell about 1 week before the peak of these hospitalizations. The distributions of new influenza-related hospitalizations per 100,000 inhabitants with time between regions followed the same pattern with a surge of new cases in the carnival region about 1 week after carnival, which did not occur in the non-carnival region. The increase of new cases for COVID-19 in the carnival region exceeded that in the non-carnival region about 1 week after the first case was reported, but these results warrant caution as for COVID-19 there were no cases reported before the carnival and social measures were introduced shortly after carnival. CONCLUSION: In this study, a mass gathering event (carnival) was associated with aggravating the spread of viral respiratory infectious diseases.

COVID-19: How to make between-country comparisons.

BACKGROUND: Different countries have adopted different containment and testing strategies for SARS-CoV-2. The difference in testing makes it difficult to compare the effect of different containment strategies. This study proposes methods to allow a direct comparison and presents the results. DESIGN: Publicly available data on the numbers of reported COVID-19-related deaths between 01 January and 17 April 2020 were compared between countries. RESULTS: The numbers of cases or deaths per 100,000 inhabitants gave severely biased comparisons between countries. Only the number of deaths expressed as a percentage of the number of deaths on day 25 after the first reported COVID-19-related death allowed a direct comparison between countries. From this comparison clear differences were observed between countries, associated with the timing of the implementation of containment measures. CONCLUSIONS: Comparisons between countries are only possible when simultaneously taking into account that the virus does not arrive in all countries simultaneously, absolute numbers are incomparable due to different population sizes, rates per 100,000 of the population are incomparable because not all countries are affected homogeneously, susceptibility to death by COVID-19 can differ between populations, and a death is only reported as a COVID-19-related death if the patient was diagnosed with SARS-CoV-2 infection. With the current methods, all these factors were accounted for and an unbiased direct comparison between countries was established. This comparison confirmed that early adoption of containment strategies is key in flattening the curve of the epidemic.