Adapting French COVID-19 vaccination campaign duration to variant dissemination

BackgroundThe outbreak of SARS-CoV-2 virus has caused a major international health crisis with serious consequences in terms of public health and economy. In France, two lockdown periods were decided in 2020 to avoid the saturation of intensive care units (ICU) and an increase in mortality. The rapid dissemination of variant SARS-CoV-2 VOC 202012/01 has strongly influenced the course of the epidemic. Vaccines have been rapidly developed. Their efficacy against the severe forms of the disease has been established, and their efficacy against disease transmission is under evaluation. The aim of this paper is to compare the efficacy of several vaccination strategies in the presence of variants in controlling the COVID-19 epidemic through population immunity. MethodsAn agent-based model was designed to simulate with different scenarios the evolution of COVID-19 pandemic in France over 2021 and 2022. The simulations were carried out ignoring the occurrence of variants then taking into account their diffusion over time. The expected effects of three Non-Pharmaceutical Interventions (Relaxed-NPI, Intensive-NPI, and Extended-NPI) to limit the epidemic extension were compared. The expected efficacy of vaccines were the values recently estimated in preventing severe forms of the disease (75% and 94%) for the current used vaccines in France (Pfizer-BioNTech and Moderna since January 11, 2021, and AstraZeneca since February 2, 2021). All vaccination campaigns reproduced an advanced age-based priority advised by the Haute Autorite de Sante. Putative reductions of virus transmission were fixed at 0, 50, 75 and 90%. The effects of four vaccination campaign durations (6-month, 12-month, 18-month and 24-month) were compared. ResultsIn the absence of vaccination, the presence of variants led to reject the Relaxed-NPI because of a high expected number of deaths (170 to 210 thousands) and the significant overload of ICUs from which 35 thousand patients would be deprived. In comparison with the situation without vaccination, the number of deaths was divided by 7 without ICU saturation with a 6-month vaccination campaign. A 12-month campaign would divide the number of death by 3 with Intensive-NPI and by 6 with Extended-NPI (the latter being necessary to avoid ICU saturation). With 18-month and 24-month vaccination campaigns without Extended-NPI, the number of deaths and ICU admissions would explode. ConclusionAmong the four compared strategies the 6-month vaccination campaign seems to be the best response to changes in the dynamics of the epidemic due to the variants. The race against the COVID-19 epidemic is a race of vaccination strategy. Any further vaccination delay would increase the need of strengthened measures such as Extended-NPI to limit the number of deaths and avoid ICU saturation.

Evaluation of high-throughput SARS-CoV-2 serological assays in a longitudinal cohort of mild COVID-19 patients: sensitivity, specificity and association with virus neutralization test

ObjectivesWe evaluated widely-used SARS-CoV-2 serological tests and their potential association with virus neutralization test (VNT) in a cohort of mild COVID-19 patients. MethodsA total of 439 specimens were longitudinally collected from 76 healthcare workers with RT-PCR-confirmed mild COVID-19. Nine serological assays developed by leading global companies (Abbott, DiaSorin, Siemens, Bio-Rad, Wantai, bioMerieux, Euroimmun) were assessed. For each test the sensitivity to detect SARS-CoV-2 antibodies was determined weekly after symptom onset. Correlation and concordance were assessed using the Spearman and Cohens Kappa coefficients, respectively. Positive percent agreement and negative percent agreement (NPA) with the VNT were also determined. ResultsThe Wantai Total Ab assay targeting the receptor binding domain (RBD) within the S protein presented the best sensitivity at different times during the course of disease. The best correlation between antibody level and neutralizing antibody titer was found with the Euroimmun S1-based IgA assay (Spearman coefficient [95%CI]: 0.71 [0.61-0.79]). A moderate concordance (Kappa [95%CI]: 0.43[0.23-0.63]) as well as the lowest NPA (33%) was found between the Wantai Total Ab assay and the VNT. Compared to the Wantai Total Ab assay, other total Ab or IgG assays targeting the S or the RBD (bioMerieux, DiaSorin, Siemens,) were more concordant with the VNT (Kappa>0.7 for the three tests) and had a higher NPA (range: 90% to 97%). ConclusionsAlthough some assays presented a better concordance with VNT than others, the present findings emphasize that commercialized serological tests including those targeting the RBD cannot substitute VNT for the assessment of functional antibody response.

DPP4 inhibitors and respiratory infection, a systematic review and meta-analysis of the CardioVascular Outcomes Trials conducted before the pandemic and implications for the management of diabetes during COVID-19

BackgroundAssociation between DPP4 inhibitors and respiratory infection remains unclear. CardioVascular Outcomes Trials (CVOTs) conducted before the COVID-19 pandemic are available. We aimed to estimate the effect of DPP4 inhibitors on the risk of respiratory infections. MethodsWe updated a previous systematic review and meta-analysis, searching for CVOTs assessing a DPP4 inhibitor in patients with type 2 diabetes mellitus. We focused on placebo-controlled CVOTs. Our primary outcome was any respiratory infection. We added a sensitivity analysis integrating non-CVOTs and active-controlled CVOTs. FindingsWe included 47 714 patients in five placebo-controlled CVOTs. Median follow-up ranged from 1{middle dot}5 years to 3 years. 4 369 events of overall respiratory infection were reported (rate of 9{middle dot}2%). DPP4 inhibitors were not associated with a different risk compared to placebo (RR = 0{middle dot}99 [95% CI: 0{middle dot}93; 1{middle dot}04]). The sensitivity analysis integrating the non-CVOTs studies and the active-controlled CVOT reached 11 349 events among 82 644 participants (rate of 13{middle dot}7%). DPP4 inhibitors were not associated with a different risk of overall respiratory infection (RR = 1{middle dot}00 [95% CI: 0{middle dot}97; 1{middle dot}03]). InterpretationOur up-dated meta-analysis provides the most powerful and least biased estimation of the association of DPP4 inhibitors and the risk of overall (non COVID-19) respiratory infection. We did not find any effect of the DPP4 inhibitors on the risk of respiratory infection. Our results support the recently published practical recommendations for the management of diabetes in patients with COVID-19, suggesting that DPP4 inhibitors should not be discontinued regarding the COVID-19 pandemic. FundingNo source of funding Panel: Research in contextO_ST_ABSEvidence before this studyC_ST_ABSFrom before the COVID19 pandemic, respiratory infections are considered potential adverse effects of DPP4 inhibitors. Randomized trials assessing DPP4 inhibitors in patients with type 2 diabetes (T2D), their meta-analyses and pharmacovigilance studies reported conflicting results. Since the last meta-analyses assessing the risk of infections with DPP4 inhibitors, powerful cardiovascular outcomes randomized trials (CVOTs) became available. Recent practical recommendations for the management of diabetes during COVID-19 suggested that DPP4 inhibitors could be continued. We updated our previous meta-analysis of CVOTs and focused to the overall risk of respiratory infection associated with DPP4 inhibitors. We searched for published and unpublished CVOTs in Medline, the Cochrane Central Register of Controlled Trials (CENTRAL), and ClinicalTrials.gov, up to January 27, 2020, using key word as "diabetes mellitus", "hypoglycemic agents", "glucose control", "randomized controlled trial", "cardiovascular diseases". Added value of this studyWe included CVOTs comparing a DPP4 inhibitor versus placebo, in people with T2D, and analysed the risk of respiratory infection with DPP4 inhibitors. We focused on placebo-controlled CVOTs to avoid the pitfalls of small study effect and heterogeneous comparators. We added a sensitivity analysis integrating non-CVOTs and non-placebo CVOTs to challenge our results and to increase the statistical power. Our meta-analysis provides the most powerful and least biased estimation of the association of DPP4 inhibitors and the risk of overall (non COVID-19) respiratory infection. Our analyses integrated 11 349 events of any respiratory infections through 82 644 patients from randomized trials. Our results did not find any association between DPP4 inhibitors use and risk of non-COVID respiratory infections. Implications of all the available evidenceThe current COVID-19 pandemic has raised some questions about pros and cons of certain cardiovascular drugs. Our results support the recent practical recommendations for the management of diabetes in patients with COVID-19, suggesting that DPP4 inhibitors should not be discontinued regarding the COVID-19 pandemic.

Modeling of systolic blood pressure reaction to antihypertensive agents in people with hypertension / 中华心血管病杂志

<p><b>OBJECTIVE</b>We used the individual patient data from clinical trials, pooled in the INDANA data set, to explore whether blood pressure reduction was related to the baseline individual characteristics, and quantify the potential associations.</p><p><b>METHODS</b>We used the data from 31 140 patients with essential hypertension recruited in four randomized placebo-controlled clinical trials, MRC35-64, MRC65-74, STEP and SYST-EU. Thiazide diuretics, β-blocker, and calcium channel blocker, three of six major BP lowering drugs were analyzed. Patients were all with the same first dosage of the drug in each trial. Age, body weight, height, level of total cholesterin (TC), systolic blood pressure (SBP) and diastolic blood pressure (DBP) when initialed and at first visit of follow-up, pharmacological treatment, gender, status of smoking, history of myocardium infarction were factors taken into model. Data were managed by software SAS(®). Statistical analyses were performed with SAS(®) and R. Model was developed to evaluate the relationship between decrease of SBP and characteristics of patients.</p><p><b>RESULTS</b>Initial SBP is the only modifier of treatment effect on SBP response in the 3 BP lowering drug classes (β = 0.09, 0.37 and 0.18, respectively). Age and initial DBP were factors significantly correlated with SBP fall for diuretic (β = 0.17 and 0.14), and age was one of factors significantly correlated with SBP fall for β-blocker (β = -0.17). Smokers would receive less SBP fall compare to non-smokers in β-blocker active treated group (β = -2.07). There is converse effect of age between the diuretic and β-blocker; older people seem sensitive to diuretic, while young people are sensitive to β-blocker. As to calcium channel antagonist class, body weight is another modifier (β = 0.06) (All P value are 0.000 except 0.050 for body weight in calcium channel antagonist class).</p><p><b>CONCLUSION</b>We identified 5 significant modifiers (baseline SBP and DBP, age, smoking status and body weight) for SBP response to treatment effect, while gender, TC and history of myocardial infarction are not modifiers for SBP response to treatment effect.</p>