The obesity paradox in Japanese COVID-19 patients.

Purpose: To investigate the effect of obesity on mortality and invasive respiratory care (IRC) in patients with COVID-19. Methods: We studied 1,105 patients for 34 months and collected data. The primary outcome was all-cause death at 29 days. The secondary outcome was IRC indicated by a pulse oximetry rate below 93% at a mask oxygenation rate of 5 L/min or more. Results: Age- and sex-adjusted multivariate regression analysis for 29-day deaths showed the significance of body mass index (BMI) > 19.6 kg/m2 (odds ratio 0.117, 95% confidence interval 0.052-0.265, P<0.001). The graphs with BMI in the abscissa showed, within a BMI between 11 and 25 kg/m2, a decreasing pattern for mortality and IRC rate, and no increase in overweight. Conclusion: In Japanese COVID-19 patients, the risk of mortality and the IRC rate decreased in underweight patients and remained low in overweight patients, suggesting the importance of the obesity paradox.

SARS-CoV-2 strain-specific anti-spike IgG ELISA utilizing spike protein produced by silkworms.

BACKGROUND: A cost-effective and eco-friendly method is needed for the assessment of humoral immunity against SARS-CoV-2 in large populations. OBJECTIVE: We investigated the performance of an ELISA that uses silkworm-produced proteins to quantify the strain-specific anti-Spike IgG (anti-S IgG) titer. METHODS: The OD values for the anti-His-tag antibody, a standard material of ELISA quantification, were measured. Correlations between the ELISA for each strain and the Abbott SARS-CoV-2 IgG II Quant assay for the wild type were evaluated with serum samples from nine participants with various infection and vaccination statuses. RESULTS: Linear dose-responses were confirmed by high coefficients of determination: 0.994, 0.994, and 0.996 for the wild-type, Delta, and Omicron (BA.1) strain assays, respectively. The coefficient of determination for the wild-type and Delta strain assays was high at 0.959 and 0.892, respectively, while the Omicron strain assay had a relatively low value of 0.563. Booster vaccinees showed similar or higher titers against all strains compared to infected persons without vaccination. The Omicron-infected persons without vaccination had lower antibody titers against wild type than did the vaccinated persons. CONCLUSIONS: This study provides data indicating that the ELISA with silkworm-produced proteins makes it possible to discriminate and quantify the strain-specific anti-S IgG antibody induced by vaccination or infection.

Sotrovimab use in Japanese inpatients with COVID-19: post-infusion adverse events.

BACKGROUND: Sotrovimab neutralizing SARS-CoV-2 remained effective at the advent of B.1 lineage of the Omicron variant in outpatients. Primarily for hospitalized patients, however, the Japanese government regulated to administer this antibody agent. As this regulation enabled close monitoring in inpatients to investigate post-infusion adverse events (AEs) and efficacy, we attempted a retrospective study while the Omicron BA.1 lineage was dominant regionally. METHODS: Subjects were inpatients with COVID-19 who received infusion of sotrovimab in our institute. In line with previous clinical trials, we included patients at risk of COVID-19 worsening and SARS-CoV-2 vaccinees, who were hospitalized as directed by the government. For statistical analyses, we reviewed background factors of demographics, imaging, and laboratory findings for the outcome infusion-related reactions including post-infusion pyrexia over 38 degrees Celsius and/or pulse oximetry below 94%. RESULTS: In a total of 139 patients, the follow-up period had a median of 200 days (range, 154-248 days). Among 119 patients (85.6%) fully vaccinated for SARS-CoV-2, 86 (61.9% of all) underwent 2 doses while 33 (23.7% of all) received 3 doses. For the outcome of pyrexia and/or dyspnea (N = 40, 28.8%), multivariate analysis showed that significant risk factors were pre-infusion lowered oximetry below 96.5% (Odds Ratio [OR] 0.344, 95% Confidence Interval [CI] 0.139-0.851, P = 0.021) and pre-infusion temperature more than 36.7 degrees Celsius (OR 4.056, 95% CI 1.696-9.701, P = 0.002). Infusion-related reactions included vomiting immediately after infusion, chill/shivering, dizziness, rash, pruritus, pyrexia, and dyspnea. The number of patients with any of these events was 44 (31.6%). Three patients (2.2%) showed worsening of COVID-19; one developed hypoxia and two died. Limitations for this study included no genome typing whether BA.1 or BA.2 lineage of the Omicron variant but the local epidemiology indicated the prevalence of BA.1. Another was sotrovimab administration for inpatients that allow precise detection of post-infusion events, confounding previous exacerbation definition including hospitalization. CONCLUSIONS: For 24 h after infusion of sotrovimab, COVID-19 patients showing pre-infusion lowered oximetry below 96.5% and/or temperature more than 36.7 degrees Celsius may have temperature elevation or dyspnea, warranting close monitoring for these risk factors.

Casirivimab-imdevimab neutralizing SARS-CoV-2: post-infusion clinical events and their risk factors.

BACKGROUND: Casirivimab-imdevimab has been developed to neutralize SARS-CoV-2. The global clinical trials in outpatients documented several adverse effects (AE), which mandate caution in Japan where part of patients return home. To investigate post-infusion clinical events and their risk factors, we attempted a retrospective study. MAIN BODY: Subjects were a consecutive series of inpatients with COVID-19 undergoing an infusion of casirivimab-imdevimab in our institute. The criteria for administration were in accordance with previous clinical trials, e.g., exclusion of patients necessitating oxygen supply. In Japan, however, SARS-CoV-2 vaccinees were eligible. Methods were review of background factors of status, imaging, and laboratory findings for the outcome of post-infusion events such as temperature increase (Temp+), pulse oximetry below 94%, and other events. Also, we documented the drug efficacy. Of a total of 96 patients with a median follow-up of 54 days, one (1.0%) died who alone was an exception demanding oxygen supply. Other 95 patients (99.0%) recovered from fever and hypoxia by Day 4 and later had no worsening of COVID-19. Median increase of body temperature was 1.0 degrees Celsius, which was used for computation of Temp+. Multivariate analysis showed that for Temp+ (n = 47), white blood cell counts more than 4.3 × 103/microliter (Odds Ratio [OR] 2.593, 95% Confidence Interval [CI] 1.060-6.338, P = 0.037) was at risk, whereas 2-time vaccination for SARS-CoV-2 (OR 0.128, 95% CI 0.026-0.636, P = 0.012) was a preventing factor. Likewise for lowered oximetry (n = 21), CT showing bilateral ground glass attenuation (OR 5.544, CI 1.599-19.228, P = 0.007) was a significant risk factor. Two patients (2.1%) showed bradycardia (asymptomatic, intervention not indicated) on Day 3 and recovery on Day 5. Limitations for this study included the difficulty distinguishing AE from worsening of COVID-19, thus we documented as clinical events. CONCLUSIONS: For 24 h after infusion of casirivimab-imdevimab, COVID-19 patients with increased white blood cell counts may be predisposed to temperature elevation more than 1.0 degrees centigrade, as may bilateral ground glass opacity to lowered oximetry. Thus, patients with leukocytosis and bilateral ground glass attenuation may need precaution for transient fever and hypoxia, respectively.