Assay of the von Willebrand factor (VWF) propeptide to identify patients with type 1 von Willebrand disease with decreased VWF survival

Type 1 von Willebrand disease (VWD) is characterized by a partial quantitative deficiency of von Willebrand factor (VWF). Few VWF gene mutations have been identified that cause dominant type 1 VWD. The decreased survival of VWF in plasma has recently been identified as a novel mechanism for type 1 VWD. We report 4 families with moderately severe type 1 VWD characterized by low plasma VWF:Ag and FVIII:C levels, proportionately low VWF:RCo, and dominant inheritance. A decreased survival of VWF in affected individuals was identified with VWF half-lives of 1 to 3 hours, whereas the half-life of VWF propeptide (VWFpp) was normal. DNA sequencing revealed a single (heterozygous) VWF mutation in affected individuals, S2179F in 2 families, and W1144G in 2 families, neither of which has been previously reported. We show that the ratio of steady-state plasma VWFpp to VWF:Ag can be used to identify patients with a shortened VWF half-life. An increased ratio distinguished affected from unaffected individuals in all families. A significantly increased VWFpp/VWF:Ag ratio together with reduced VWF:Ag may indicate the presence of a true genetic defect and decreased VWF survival phenotype. This phenotype may require an altered clinical therapeutic approach, and we propose to refer to this phenotype as type-1C VWD

Surveillance of adverse events in the treatment of drug-resistant tuberculosis: first global report

WHO (World Health Organization) recommends countries to implement pharmacovigilance and to collect information on aDSM (active drug safety monitoring and management of adverse events-AEs). Aim of this prospective study was to evaluate the frequency and severity of AEs to anti-tuberculosis (TB) drugs in a cohort of consecutive TB patients treated with new (i.e. bedaquiline, delamanid) and repurposed (i.e.. clofazimine, linezolid) drugs, based on the WHO aDSM project. AEs were collected prospectively after attribution to a specific drug together with demographic, bacteriological, radiological and clinical information at diagnosis and during therapy. This interim analysis included patients who completed or were still on treatment at time of data collection. Globally, 45 centres from 26 countries/regions reported 658 patients (68.7% males, 4.4% HIV co-infected) treated as follows: 87.7% with bedaquiline, 18.4% with delamanid (6.1% with both), 81.5% with linezolid and 32.4% with clofazimine. Overall 504 AE episodes were reported: 447 (447/504, 88.7%) were classified as minor (grade 1–2) and 57 (57/504, 11.3%) as serious (grade 3–5). The majority of the 57 serious AEs reported by 55 patients (51/57; 89.5%) ultimately resolved. Among patients reporting serious AEs some drugs held responsible were discontinued: bedaquiline in 0.35% (2/577), delamanid in 0.8% (1/121), linezolid in 1.9% (10/536) and clofazimine in 1.4% (3/213) of patients. Serious AEs were reported in 6.9% (9/131) of patients treated with amikacin, 0.4% (1/221) with ethionamide/prothionamide, 2.8% (15/536) with linezolid and 1.8% (8/498) with cycloserine/terizidone. The aDSM study provided valuable information but implementation needs scaling-up to support patient-centred care

Outcome of treatment of MDR-TB or drug-resistant patients treated with bedaquiline and delamanid: Results from a large global cohort.

The World Health Organization (WHO) recommends countries introduce new anti-TB drugs in the treatment of multidrug-resistant tuberculosis. The aim of the study is to prospectively evaluate the effectiveness of bedaquiline (and/or delamanid)- containing regimens in a large cohort of consecutive TB patients treated globally. This observational, prospective study is based on data collected and provided by Global Tuberculosis Network (GTN) centres and analysed twice a year. All consecutive patients (including children/adolescents) treated with bedaquiline and/or delamanid were enrolled, and managed according to WHO and national guidelines. Overall, 52 centres from 29 countries/regions in all continents reported 883 patients as of January 31st 2021, 24/29 countries/regions providing data on 100% of their consecutive patients (10-80% in the remaining 5 countries). The drug-resistance pattern of the patients was severe (>30% with extensively drug-resistant -TB; median number of resistant drugs 5 (3-7) in the overall cohort and 6 (4-8) among patients with a final outcome). For the patients with a final outcome (477/883, 54.0%) the median (IQR) number of months of anti-TB treatment was 18 (13-23) (in days 553 (385-678)). The proportion of patients achieving sputum smear and culture conversion ranged from 93.4% and 92.8% respectively (whole cohort) to 89.3% and 88.8% respectively (patients with a final outcome), a median (IQR) time to sputum smear and culture conversion of 58 (30-90) days for the whole cohort and 60 (30-100) for patients with a final outcome and, respectively, of 55 (30-90) and 60 (30-90) days for culture conversion. Of 383 patients treated with bedaquiline but not delamanid, 284 (74.2%) achieved treatment success, while 25 (6.5%) died, 11 (2.9%) failed and 63 (16.5%) were lost to follow-up