Quality of life in a large multinational haemophilia B cohort (The B-Natural study) - Unmet needs remain.

INTRODUCTION: The B-Natural study is a multicentre, multinational, observational study of haemophilia B (HB) designed to increase understanding of clinical manifestations, treatment and quality of life (QoL). AIM: To characterise and compare QoL in HB across disease severity groups and individuals with inhibitors to identify gaps in treatment. METHODS: A total of 224 individuals from 107 families were enrolled from a total of 24 centres in North America (n = 16), Europe (n = 7) and Asia (n = 1). Of these, 68 (30.4%) subjects had severe (<1 IU/dL), median age 15.6 years, 114 (50.9%) moderate (1-5 IU/dL), age 13.3 years, and 42 (18.8%) mild (>5-< 40 IU/dL), age 12.1 years, disease. Twenty-nine participants had inhibitors or a history of inhibitors. Three versions of the EQ-5D instrument were used as a measure of QoL: proxy (ages 4-7), youth (ages 8-15) and self (age 16+). Each instrument included a visual analogue scale ranging from 100 (best health) to 0 (worst health) to assess current day's health (EQ VAS). Range-of-motion (ROM) for elbows, knees and ankles was assessed using a four-point scale, from which a composite score was calculated. RESULTS: In all severity groups, a proportion of subjects showed less than optimal QoL. The majority of the mild and moderate severe participants reported a normal EQ-5D health profile (79% and 72%, respectively), whereas about half (47%) of the severe participants and only 13% of the inhibitor participants reported this profile. CONCLUSION: The B-Natural study reveals impacted QoL in all disease severities of HB including those with inhibitors. Unmet needs remain and include nonsevere HB.

Final results of the PUPs B-LONG study: evaluating safety and efficacy of rFIXFc in previously untreated patients with hemophilia B.

PUPs B-LONG evaluated the safety and efficacy of recombinant factor IX Fc fusion protein (rFIXFc) in previously untreated patients (PUPs) with hemophilia B. In this open-label, phase 3 study, male PUPs (age <18 years) with hemophilia B (≤2 IU/dL of endogenous factor IX [FIX]) were to receive treatment with rFIXFc. Primary end point was occurrence of inhibitor development, with a secondary end point of annualized bleed rate (ABR). Of 33 patients who received ≥1 dose of rFIXFc, 26 (79%) were age <1 year at study entry and 6 (18%) had a family history of inhibitors. Twenty-eight patients (85%) received prophylaxis; median dosing interval was 7 days, with an average weekly dose of 58 IU/kg. Twenty-seven patients (82%) completed the study. Twenty-one (64%), 26 (79%), and 28 patients (85%) had ≥50, ≥20, and ≥10 exposure days (EDs) to rFIXFc, respectively. One patient (3.03%; 95% confidence interval, 0.08% to 15.76%) developed a low-titer inhibitor after 11 EDs; no high-titer inhibitors were detected. Twenty-three patients (70%) had 58 treatment-emergent serious adverse events; 2 were assessed as related (FIX inhibition and hypersensitivity in 1 patient, resulting in withdrawal). Median ABR was 1.24 (interquartile range, 0.00-2.49) for patients receiving prophylaxis. Most (>85%) bleeding episodes required only 1 infusion for bleed resolution. In this first study reporting results with rFIXFc in pediatric PUPs with hemophilia B, rFIXFc was well tolerated, with the adverse event profile as expected in a pediatric hemophilia population. rFIXFc was effective, both as prophylaxis and in the treatment of bleeding episodes. This trial was registered at www.clinicaltrials.gov as #NCT02234310.

Efficacy and safety of simoctocog alfa (Nuwiq®) in patients with severe hemophilia A: a review of clinical trial data from the GENA program.

Simoctocog alfa (human-cl rhFVIII, Nuwiq®) is a 4th generation recombinant FVIII (rFVIII), without chemical modification or fusion with any other protein/fragment. Nuwiq® is produced in a human embryonic kidney cell line (HEK293F), which ensures human-specific post-translational protein processing. Nuwiq® was evaluated in seven prospective clinical studies in 201 adult and pediatric previously treated patients (PTPs) with severe hemophilia A. The NuProtect study in 110 previously untreated patients (PUPs) is ongoing. The mean half-life of Nuwiq® was 15.1-17.1 h in PTP studies with adults and adolescents, and 12.5 h in children aged 2-12 years. Clinical trials in PTPs demonstrated the efficacy and safety of Nuwiq® in the prevention and treatment of bleeds and as surgical prophylaxis. In the NuPreviq study of pharmacokinetic (PK)-guided personalized prophylaxis in 66 adult PTPs, 83% of patients had no spontaneous bleeds during 6 months of personalized prophylaxis and 57% were treated ⩽2 per week. No FVIII inhibitors were detected in PTPs after treatment with 43,267 injections and >80 million IU of Nuwiq®. Interim data for 66 PUPs with ⩾20 exposure days to Nuwiq® in NuProtect demonstrated a low cumulative high-titer inhibitor rate of 12.8% [actual incidence 12.1% (8/66)] and convincing efficacy and safety.

Risk Factors for the Progression from Low to High Titres in 260 Children with Severe Haemophilia A and Newly Developed Inhibitors.

In children with severe haemophilia A, inhibitors to factor VIII (FVIII) usually develop during the first 50 treatment exposure days and are classified as low or high titre depending on the peak inhibitor titre being greater or less than 5 Bethesda units/mL (BU/mL). Classification of the inhibitor may change with time, as some low-titre inhibitors progress to high titre following re-exposure to FVIII concentrate. The aim of this study was to investigate potential risk factors for such a progression in children with severe haemophilia A and newly diagnosed inhibitors. This study was a follow-up study of the PedNet Registry and included 260 children with severe haemophilia A and inhibitors born between 1990 and 2009 and recruited consecutively from 31 haemophilia centres. Clinical and laboratory data were collected from the date of each child's first positive inhibitor test for at least 3 years. At the time of first positive inhibitor test, 49% (n = 127) had low-titre inhibitors, with 50% of them progressing to high titre and only 25% maintaining low titres. The FVIII gene (F8) mutation type was known in 247 patients (95%), and included 202 (82%) null mutations. The progression to high-titre inhibitors was associated with null F8 mutations (odds ratio [OR]: 2.6; 95% confidence interval [CI]: 1.0­6.5), family history of inhibitors (OR: 7.2; 95% CI: 1.8­28.4) and the use of high-dose immune tolerance induction, defined as ≥100 IU FVIII concentrate/kg/d (OR: 3.9; 95% CI: 1.5­10.0). These results suggest that high-dose immune tolerance induction should be avoided as the initial strategy in patients who develop low-titre FVIII inhibitors.

Experience of Advate rAHF-PFM in previously untreated patients and minimally treated patients with haemophilia A.

We report a prospective trial of 55 previously untreated patients (PUPs) and minimally treated patients (MTPs) with severe/moderately severe haemophilia A (baseline factor VIII [FVIII] ≤2%) treated with a single FVIII replacement product. It was the objective of this study to evaluate the immunogenicity, efficacy, and safety of rAHF-PFM (Advate®). On-demand or prophylactic treatment regimens were determined at the discretion of the investigator. rAHF-PFM was also permitted for perioperative management. There were 633 bleeding episodes (BEs), including 517 treated, and 466 rated for efficacy. Haemostatic efficacy was considered excellent/good in 93% of 466 rated treatments. Of 517 treated BEs, 463/517 (90%) were managed with one (356/517 [69%]) or two infusions (107/517 [21%]). There were 27 surgeries. Intraoperative (n=22) and postoperative (n=25) haemostatic efficacies were considered excellent or good in 100% of rated surgeries. Related serious adverse events (SAEs) were inhibitor development in 16/55 (29.1%) subjects who received at least one infusion of rAHF-PFM. Non-serious, related adverse events (AEs) were few in number (14 in eight subjects). The odds ratio (OR [95% Confidence Interval, CI]) of developing inhibitors was significantly higher in subjects with a family history of inhibitor (4.95[1.29-19.06]), non-Caucasian ethnicity (4.18, [1.18-14.82]), and intensive treatment at high dose (4.5 [1.05-19.25]) within ≤20 exposure days (EDs). In conclusion, rAHF-PFM was safe and effective for the management and perioperative coverage of PUPs/MTPs with severe/moderately severe haemophilia A. This report supports previous findings from studies in which family history of inhibitor, non-Caucasian ethnicity, and high intensity treatment were associated with high risk of inhibitor development.