Pharmacodynamics of eftrenonacog-alfa (rFIX-Fc) in severe hemophilia B patients: A real-life study

International audienceEftrenonacog-alfa is a recombinant factor IX-Fc fusion protein increasingly prescribed in hemophilia B patients. We aimed to assess its pharmacodynamics (PD) in real-life setting via FIX activity measurement and thrombin generation assay (TGA). Sixty samples from 15 severe hemophilia B treated patients were collected at different time points. FIX activity was measured using product-specific one-stage clotting assay (reference method) and two chromogenic assays (CSA) (Biophen FIX and Rox FIX). TGA was triggered with 1 pM tissue factor. Five parameters were analyzed: lag time (LT), time to peak (TTP), peak height (PH), endogenous thrombin potential (ETP), and velocity. PD models were built to characterize their relationships with FIX activity, using mixed effects models. Mean trough FIX level was estimated at 4.64 (±1.50) IU/dl with a recovery at 0.78 (±0.16) IU/dl per 1 IU/kg injected dose. FIX activity ranged between 1 and 86 IU/dl with 21.5 IU/dl median value. Biophen FIX and Rox FIX allowed reliable measurements except in samples with FIX 30%). PD models revealed that velocity was the most sensitive TGA parameter to FIX activity followed by PH, ETP, TTP and finally LT. Following FIX activity peak after eftrenonacog-alfa injection, velocity decreased first, followed by PH then ETP. Both CSA failed to accurately measure FIX in severe hemophilia B patients receiving eftrenonacog-alfa throughout the measuring range. TGA could be an additional valuable tool to evaluate hemostasis balance in treated patients

Lack of antibodies against seasonal coronavirus OC43 nucleocapsid protein identifies patients at risk of critical COVID-19

Background: The vast majority of COVID-19 patients experience a mild disease. However, a minority suffers from critical disease with substantial morbidity and mortality. Objectives: To identify individuals at risk of critical COVID-19, the relevance of a seroreactivity against seasonal human coronaviruses was analyzed. Methods: We conducted a multi-center non-interventional study comprising 296 patients with confirmed SARS-CoV-2 infections from four tertiary care referral centers in Germany and France. The ICU group comprised more males, whereas the outpatient group contained a higher percentage of females. For each patient, the serum or plasma sample obtained closest after symptom onset was examined by immunoblot regarding IgG antibodies against the nucleocapsid protein (NP) of HCoV 229E, NL63, OC43 and HKU1. Results: Median age was 60 years (range 18-96). Patients with critical disease (n=106) had significantly lower levels of anti-HCoV OC43 nucleocapsid protein (NP)-specific antibodies compared to other COVID-19 inpatients (p=0.007). In multivariate analysis (adjusted for age, sex and BMI), OC43 negative inpatients had an increased risk of critical disease (adjusted odds ratio (AOR) 2.68 [95% CI 1.09 -7.05]), higher than the risk by increased age or BMI, and lower than the risk by male sex. A risk stratification based on sex and OC43 serostatus was derived from this analysis

Metabolomic analyses of COVID-19 patients unravel stage-dependent and prognostic biomarkers

Abstract The circulating metabolome provides a snapshot of the physiological state of the organism responding to pathogenic challenges. Here we report alterations in the plasma metabolome reflecting the clinical presentation of COVID-19 patients with mild (ambulatory) diseases, moderate disease (radiologically confirmed pneumonitis, hospitalization and oxygen therapy), and critical disease (in intensive care). This analysis revealed major disease- and stage-associated shifts in the metabolome, meaning that at least 77 metabolites including amino acids, lipids, polyamines and sugars, as well as their derivatives, were altered in critical COVID-19 patient’s plasma as compared to mild COVID-19 patients. Among a uniformly moderate cohort of patients who received tocilizumab, only 10 metabolites were different among individuals with a favorable evolution as compared to those who required transfer into the intensive care unit. The elevation of one single metabolite, anthranilic acid, had a poor prognostic value, correlating with the maintenance of high interleukin-10 and -18 levels. Given that products of the kynurenine pathway including anthranilic acid have immunosuppressive properties, we speculate on the therapeutic utility to inhibit the rate-limiting enzymes of this pathway including indoleamine 2,3-dioxygenase and tryptophan 2,3-dioxygenase