First report of safety and efficacy of a glycoPEGylated FVIII (N8-GP) in previously treated pediatric patients with severe hemophilia A-results from the international phase 3 pathfinder (TM) 5 trial

WOS: 00037994090017

Safety and efficacy of a glycoPEGylated rFVIII (turoctocog alpha pegol, N8-GP) in paediatric patients with severe haemophilia A

WOS: 000409564600007PubMed ID: 28692108Turoctocog alfa pegol (N8-GP, Novo Nordisk, Bagsvaerd, Denmark), an extended half-life glycoPEGylated recombinant factor VIII (rFVIII), is being developed for prophylaxis and treatment of bleeds in haemophilia A patients. pathfinder (TM) 5 is a multinational, open-label, single-arm trial to assess safety, efficacy and pharmacokinetics of N8-GP in paediatric (50 exposure days [ED] for patients aged 0-5 years [younger cohort]; >150 ED for patients aged 6-11 years [older cohort]) were included. For prophylaxis, N8-GP was dosed at 50-75 IU/kg twice weekly; bleeds were treated with 20-75 IU/kg. Half-life was estimated for the patients' previous FVIII product and for N8-G P. Sixty-eight patients received N8-GP; none developed inhibitors and no other concerns were identified. Median annualised bleeding rate was 1.95 (1.94 and 1.97 in the younger and older cohorts, respectively). Twenty-nine patients (42.6 %;15 younger and 14 older children, respectively) did not report any bleeding while on N8-GP prophylaxis; 39 patients (57.4 %; 19 younger and 20 older children, respectively) reported 70 bleeds (all mild/moderate). N8-GP treatment was successful for 78.6 % of bleeds in all patients, 80.0 % in younger and 77.5 % in older patients. Most bleeds (80.0 %) were treated with <= 2 injections. Half-life ratio between N8-GP and the patients' previous FVIII product was 1.85. N8-GP was well tolerated and provided effective prophylaxis and treatment of bleeds in paediatric patients with severe haemophilia A.Novo Nordisk A/S (Bagsvaerd, Denmark)Novo NordiskThis trial was sponsored by Novo Nordisk A/S (Bagsvaerd, Denmark). The sponsor was responsible for trial operations, including data analysis

Immune tolerance induction in severe haemophilia A: A UKHCDO inhibitor and paediatric working party consensus update.

INTRODUCTION In good risk patients (historic inhibitor peak < 200BU), the International Immune Tolerance Study demonstrated equal efficacy to induce tolerance between high (200iu/kg/day) and low dose (50iu/kg ×3 times/week) immune tolerance induction (ITI) regimens. However, the trial stopped early on account of the excessive bleed rate in the low dose ITI arm. METHODS United Kingdom Haemophilia Centre Doctors' Organization (UKHCDO) Paediatric and Inhibitor working parties considered available ITI data alongside the bi-phenotypic antibody emicizumab (Hemlibra®) efficacy and safety data to develop a consensus guideline for the future UK ITI guideline. RESULTS This revision of UKHCDO ITI guidance incorporates the recommendation to use emicizumab as a prophylaxis haemostatic agent to reduce bleeding rates and to facilitate low dose and reduced frequency of FVIII CFC for ITI in the majority of children. CONCLUSION This consensus protocol will facilitate future evaluation of ITI outcomes in the evolving landscape of haemophilia therapeutics and ITI strategies

Characterization and treatment of congenital thrombotic thrombocytopenic purpura.

Congenital Thrombotic Thrombocytopenic Purpura (cTTP) is an ultra rare thrombomicroangiopathy caused by an inherited deficiency of ADAMTS13. There is limited data on the genotype-phenotype correlation and no consensus on treatment. We reviewed the largest cohort of cTTP cases, diagnosed in the UK, over the past 15 years. 73 cases of cTTP were diagnosed, confirmed by genetic analysis. 93% were alive at the time of review. 36% had homozygous mutations and 64% compound heterozygous mutations. Two presentation peaks were seen, childhood (median diagnosis age 3.5 years) and adulthood, typically related to pregnancy (median diagnosis age 31 years). Genetic mutations differed by age of onset with pre-spacer mutations more likely to be associated with childhood-onset (p=0.0011). 69% of adult presentations were associated with pregnancy. Fresh Frozen Plasma (FFP) and intermediate purity factor VIII concentrate were used as treatment. 88% of patients with normal blood counts but headaches, lethargy or abdominal pain reported symptom resolution with prophylactic therapy although the most common currently used regimen of three weekly FFP proved insufficient for 70% of patients and weekly or fortnightly infusions were required. Stroke incidence was significantly reduced in patients receiving prophylactic therapy (2% versus 17%, p=0.04). Long term, there is a risk of end organ damage, seen in 75% of patients with a late diagnosis of cTTP. In conclusion, pre-spacer mutations are associated with earlier development of cTTP symptoms. Prophylactic ADAMTS13 replacement decreases the risk of end organ damage such as ischemic stroke and resolved previously unrecognized symptoms in patients with non-overt disease

Whole-genome sequencing of a sporadic primary immunodeficiency cohort

Primary immunodeficiency (PID) is characterized by recurrent and often life-threatening infections, autoimmunity and cancer, and it poses major diagnostic and therapeutic challenges. Although the most severe forms of PID are identified in early childhood, most patients present in adulthood, typically with no apparent family history and a variable clinical phenotype of widespread immune dysregulation: about 25% of patients have autoimmune disease, allergy is prevalent and up to 10% develop lymphoid malignancies1-3. Consequently, in sporadic (or non-familial) PID genetic diagnosis is difficult and the role of genetics is not well defined. Here we address these challenges by performing whole-genome sequencing in a large PID cohort of 1,318 participants. An analysis of the coding regions of the genome in 886 index cases of PID found that disease-causing mutations in known genes that are implicated in monogenic PID occurred in 10.3% of these patients, and a Bayesian approach (BeviMed4) identified multiple new candidate PID-associated genes, including IVNS1ABP. We also examined the noncoding genome, and found deletions in regulatory regions that contribute to disease causation. In addition, we used a genome-wide association study to identify loci that are associated with PID, and found evidence for the colocalization of-and interplay between-novel high-penetrance monogenic variants and common variants (at the PTPN2 and SOCS1 loci). This begins to explain the contribution of common variants to the variable penetrance and phenotypic complexity that are observed in PID. Thus, using a cohort-based whole-genome-sequencing approach in the diagnosis of PID can increase diagnostic yield and further our understanding of the key pathways that influence immune responsiveness in humans

Publisher Correction: Whole-genome sequencing of a sporadic primary immunodeficiency cohort (Nature, (2020), 583, 7814, (90-95), 10.1038/s41586-020-2265-1)

An amendment to this paper has been published and can be accessed via a link at the top of the paper