The World Federation of Hemophilia World Bleeding Disorders Registry: A Two-year Update

The World Federation of Hemophilia World Bleeding Disorders Registry: A Two-year Update

Year: 2020
Grants:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
Author(s):
Barbara Konkle, MD, Bloodworks Northwest; Cedric Hermans, MD Ph.D., St-Luc University Hospital; Donna Coffin, M.Sc., World Federation of Hemophilia; Declan Noone, M.Sc., European Haemophilia Consortium; Emily Ayoub, Ph.D., World Federation of Hemophilia; Ellia Tootoonchian, M.Sc., World Federation of Hemophilia; Glenn Pierce, MD, World Federation of Hemophilia; Alfonso Iorio, MD PhD FRCPC, McMaster University; Jamie O'Hara, M.Sc., HCD Economics; Mayss Naccache, M.Sc., World Federation of Hemophilia; Saliou Diop, MD, Cheikh Anta Diop University; Toong Youttananukorn, Ph.D., World Federation of Hemophilia; Vanessa Byams, DrPH, Centers for Disease Control and Prevention

Objective:

As a prospective, longitudinal, observational registry of patients with hemophilia (PWH) A and B, the World Bleeding Disorders Registry (WBDR) aims to collect uniform and standardized patient data and guide clinical practice across the world. The WBDR was established in January 2018 by the World Federation of Hemophilia (WFH), with a five-year target of 10,000 patients at 200 Hemophilia Treatment Centres (HTCs) in at least 50 countries.

Methods:

Data collection occurs at the level of participating HTCs and include data on basic demographics, diagnostics, and clinical variables included in the Minimal Data Set, in addition to an Extended Data Set to obtain more complete patient data. All data entered in the WBDR are quality assessed through the WFH Data Quality Accreditation Program. Additionally, an international data integration component was developed to conduct data transfer from existing patient registries to the WBDR.

Summary:

In the first two years, 80 HTCs from 38 countries have received ethics approval. Over 5200 PWH have been enrolled, including 771 patients imported directly from the Czech National Hemophilia Program Registry via data transfer. Patients registered in the WBDR represent all regions of the world and all World Bank Gross National Income (GNI) categories. Trends in global care around the world are beginning to emerge from this early data: the median age at diagnosis for severe patients, an indicator of the level of care in a country, varies considerably based on GNI: ranging from 45 months in low income countries, to 25, 12 and 10 in lower-middle, upper-middle and high income countries respectively. Bleed rates, treatment regimens and factor use also highlight large discrepancies in care globally.

Conclusions:

The significant progress the WBDR has accomplished in its first two years laid a solid foundation on which the registry will continue to expand. This global network of HTCs and patients has started providing real-world data, on which evidence to improve the quality of care worldwide will be generated. The WFH thanks the many dedicated health care providers and patients who are part of this important initiative.

The WBDR is supported by our Visionary Partners: SOBI and Takeda; and our Collaborating Partners: Bayer, CSL Behring, Grifols, Pfizer, and Roche.

Bone and joint health markers in persons with hemophilia A treated with emicizumab in the HAVEN 3 clinical trial

Bone and joint health markers in persons with hemophilia A treated with emicizumab in the HAVEN 3 clinical trial

AWARDED/PRESENTED: 2020
GRANT/PROGRAM:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
RESEARCHERS:
Joanne I. Adamkewicz, PhD, Genentech, Inc.; Anna Kiialainen, PhD, F. Hoffmann-La Roche Ltd; Tiffany Chang, MD, MAS, Genentech, Inc.; Christine L. Kempton, MD, MSc, Emory University School of Medicine; Giancarlo Castaman, MD, Careggi University Hospital; Markus Niggli, PhD, F. Hoffmann-La Roche Ltd; Ido Paz-Priel, MD, Genentech, Inc.
Final Results of PUPs B-LONG Study: Evaluating Safety and Efficacy of rFIXFc in Previously Untreated Patients With Hemophilia B

Final Results of PUPs B-LONG Study: Evaluating Safety and Efficacy of rFIXFc in Previously Untreated Patients With Hemophilia B

AWARDED/PRESENTED: 2020
GRANT/PROGRAM:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
RESEARCHERS:
Anna Klukowska, MD, MedIcal University of Warsaw; Antoine Rauch, MD, PhD, Lille University Hospital Center (CHU) Lille; Amy Shapiro, MD, Indiana Hemophilia and Thrombosis Center; Bent Winding, MD, Swedish Orphan Biovitrum AB; Deepthi Jayawardene, MD, Sanofi; Beatrice Nolan, MD, Our Lady's Children's Hospital; Julie Curtin, MBBS, PhD, The Children's Hospital at Westmead; Kathelijn Fischer, MD, PhD, University Medical Center Utrecht; Margaret Ragni, MD, MPH, University of Pittsburgh Medical Center; Michael Recht, MD, PhD, Oregon Health and Science University; Raina Liesner, MD, Great Ormond Street Hospital; Sriya Gunawardene, MD, Sanofi; Stacey Poloskey, MD, Sanofi
Final Results of PUPs A-LONG Study: Evaluating Safety and Efficacy of rFVIIIFc in Previously Untreated Patients With Hemophilia A

Final Results of PUPs A-LONG Study: Evaluating Safety and Efficacy of rFVIIIFc in Previously Untreated Patients With Hemophilia A

AWARDED/PRESENTED: 2020
GRANT/PROGRAM:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
RESEARCHERS:
Amy Dunn, MD, Nationwide Children's Hospital; Bent Winding, MD, Swedish Orphan Biovitrum AB; Christoph Königs, MD, University Hospital Frankfurt; Deepthi Jayawardene, MS, Sanofi; Beatrice Nolan, MD, Our Lady's Children's Hospital; Manuel Carcao, MD, The Hospital for Sick Children; Margareth C. Ozelo, MD, PhD, University of Campinas; Michele Schiavulli, MD, A.O.R.N. Santobono-Pausilipon; Raina Liesner, MD, Great Ormond Street Hospital; Roshni Kulkarni, MD, Michigan State University; Simon A. Brown, MBBS, MD, Queensland Children’s Hospital; Sriya Gunawardena, MD, Sanofi; Sutirtha Mukhopadhyay, MBBS, Sanofi
Four-year safety and efficacy of N8-GP (ESPEROCT®) in previously treated adolescents/adults with hemophilia A in the completed pathfinder 2 trial

Four-year safety and efficacy of N8-GP (ESPEROCT®) in previously treated adolescents/adults with hemophilia A in the completed pathfinder 2 trial

Year: 2019
Grants:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
Author(s):
Miguel Escobar, Allison P Wheeler, Milan S Geybels, David L Cooper, Steven Lentz

Objective:

The adolescent/adult pivotal phase 3 pathfinder 2 trial assessed N8-GP (turoctocog alfa pegol, ESPEROCT®) use for routine prophylaxis and treatment of bleeds in previously treated patients (PTPs).

Methods:

pathfinder 2 was a multi-center, multi-national, single-arm study evaluating safety, efficacy and pharmacokinetics. Adolescents/adults (aged ≥12 y) with severe hemophilia A were administered prophylaxis (50 IU/kg Q4D) in the main phase with option for eligible patients (0-2 bleeds in prior 6 months) to randomize (2:1) to 75 IU/kg Q7D or 50 IU/kg Q4D during extension 1 (24 weeks) and continue treatment into extension 2. An on-demand group was included throughout. Current analysis covers January 2012 through December 2018.

Summary:

Of the 186 PTPs (including 46 [25%] from the US) enrolled in the main phase, 150 (81%) started extension 1, 139 (75%) completed extension 1, and 128 (69%) completed the study. Mean age was 31.1 years, weight 75 kg and BMI 24.3.

The complete trial covers 785 patient-years of treatment (66,577 exposure days [ED]) during which there were 2,758 bleeds, including 1,807 (66%) spontaneous bleeds and 1,735 (63%) joint bleeds. Twelve patients treated on-demand for a mean 3.1 years reported nearly half of all bleeds (1,270, 46%), including 971 (54%) spontaneous bleeds and 627 (36%) joint bleeds. Hemostatic efficacy was rated excellent/good in 2,470 (90%) episodes; 2,614 bleeds (95%) were treated with 1-2 injections.

Of 175 patients on prophylaxis, 55 of 110 eligible were randomized in extension 1. For 177 patients treated with 50 IU/kg Q4D prophylaxis for 613 years (57,723 ED), 126 (71%) experienced 1,312 bleeds. For 61 low-bleed patients with 134 years (7,255 ED) on 75 IU/kg Q7D prophylaxis, 53 (87%) experienced 176 bleeds. Median ABRs are shown in the TABLE.

  50 IU/kg Q4D 75 IU/kg Q7D
n 177 61
Mean treatment 3.5 years 2.2 years
Median ABR 0.8 1.7

 

N8-GP mean trough levels were 3.1 IU/dL on 50 IU/kg Q4D and 1.0 IU/dL on 75 IU/kg Q7D.

A total of 1,827 adverse events were reported over 785 exposure years, including 63 serious adverse events. One patient with an intron 22 inversion developed a low-titer inhibitor at 93 ED and was withdrawn when it progressed to >5 BU. Non-neutralizing anti-PEG antibodies were seen at baseline in 12 patients (6.5%) prior to first N8-GP exposure and 11 (5.9%), who had negative anti-PEG at baseline, had positive antibodies after exposure.

Conclusion:

These data support the safety and efficacy of N8-GP in a controlled phase 3 trial setting in adolescents/adults. Prophylaxis with N8-GP with a consistent dose/interval (50 IU/kg Q4D) was effective in preventing bleeds; extended dosing was evaluated as successful for a subgroup of low-bleed patients. No significant safety issues were identified. 

Five-year safety and efficacy of N8-GP (ESPEROCT®) in previously treated children with hemophilia A in the completed pathfinder 5 trial

Five-year safety and efficacy of N8-GP (ESPEROCT®) in previously treated children with hemophilia A in the completed pathfinder 5 trial

Year: 2019
Grants:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
Author(s):
Leslie Raffini, Janice M Staber, Donald L Yee, Suchitra Acharya, Wan Hui Ong Clausen, David L Cooper, Susan Kearney

Objective:

The completed pediatric phase 3 pathfinder 5 trial assessed the safety and efficacy of N8-GP (turoctocog alfa pegol, ESPEROCT®) use for routine prophylaxis and treatment of breakthrough bleeds in previously treated children.

Methods:

pathfinder 5 was a multicenter, multinational, single-arm study evaluating safety, efficacy, and pharmacokinetics. Children (aged <12) with severe hemophilia A were administered prophylaxis (target 60 [50-75] IU/kg twice weekly) in the main phase (26 weeks) followed by an extension phase. Current analysis covers study initiation (February 2013) through completion (September 2018).

Summary:

Of the 68 children (34 aged 0-5, 34 aged 6-11) enrolled, 63 completed the main phase and 62 completed the extension. Most (95%) were previously on prophylaxis. The total study period amounted to 306 patient-years (32,138 exposure days); median (mean) patient exposure was 4.9 (4.5) years.

Overall, 838 adverse events (AEs) were reported; 18 serious AEs included 2 possibly/probably related to N8-GP (severe allergic reaction [1] and increasing bleeding symptoms [1]). No inhibitor development was observed in the trial. Two AEs resulted in withdrawal; a third patient with severe allergic reactions (after 4 doses) that resolved after 2 hours without any treatment met preestablished withdrawal criteria. There were no anti-PEG antibodies of clinical significance; however, 21 (31%) patients had anti-PEG antibodies at baseline (prior to exposure), and 1 patient had a single positive measurement after exposure at a titer <1.

Overall, 55 patients (81%) reported 330 bleeds during the study; most were traumatic (67%). The success rate for hemostasis was 84% (excellent/good); 71% were treated with 1 injection, and 88% of patients were successfully treated with 1-2 injections. Median (mean) utilization for bleeds was 68 (95) IU/kg.

Median ABRs are shown below; estimated mean ABR was 1.1. Forty-seven percent of children had no spontaneous bleeds throughout the trial. Of 13 children with 17 target joints at baseline, 77% (main phase) and 46% (complete trial) reported no bleeds in their target joints. For those previously on prophylaxis, the mean observed ABR was 2.3 compared with the historical ABR of 6.4. The mean prophylaxis dose was 64.7 IU/kg with an interval of 3.5 days.

Median ABR Age 0-5 y Age 6-11 y Total
Overall 0.6 0.9 0.8
Spontaneous 0.1 0.2 0.2
Traumatic 0.3 0.8 0.5

 

N8-GP prolonged single dose half-life by 1.9x compared with the child’s prior FVIII product. The mean trough levels on twice-weekly dosing were 0.019 IU/mL (0.016 ages 0-5, 0.024 ages 6-11).

Conclusion:

These data support the safety and efficacy of N8-GP in a controlled phase 3 trial setting in children. Prophylaxis with N8-GP using a consistent dose/interval (65 IU/kg twice weekly) was effective in preventing bleeds. No unexpected safety issues were identified. 

Baseline patient characteristics in ReITIrate: A prospective study of rescue ITI with recombinant factor VIII Fc fusion protein (rFVIIIFc) in patients who have failed previous ITI attempts

Baseline patient characteristics in ReITIrate: A prospective study of rescue ITI with recombinant factor VIII Fc fusion protein (rFVIIIFc) in patients who have failed previous ITI attempts

Year: 2019
Grants:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
Author(s):
Stefan Lethagen, Christoph Königs, Shannon Meeks, Håkan Malmström, Nisha Jain

Objective:

Inhibitor development is the most serious complication of hemophilia A therapy. Immune tolerance induction (ITI) is the gold standard for inhibitor eradication, restoring factor VIII (FVIII) responsiveness. Retrospective data on ITI therapy using rFVIIIFc have been reported (Carcao et al. Haemophilia. 2018). The ReITIrate study (NCT03103542) was designed to prospectively evaluate success of rescue ITI with rFVIIIFc.

Methods:

ReITIrate, a prospective, interventional, multicenter, open-label study, enrolled patients with severe hemophilia A and inhibitors, who failed previous ITI attempts. The primary purpose is to describe the outcome of ITI performed with rFVIIIFc (200 IU/kg/day) within a maximum of 60 weeks. Here, patient baseline characteristics are reported using descriptive statistics and listings.

Summary:

Sixteen subjects were included in the study between November 2017 and December 2018. The median (range) age at study enrollment was 7.5 (2–46) years. Seven subjects had a known family history of inhibitors. The median (range) number of prior ITI attempts was 1 (1–3) and the median (range) total ITI duration was 51.5 (12–155) months. All subjects had previously received high-dose ITI, with 3 subjects receiving plasma products, 6 subjects receiving recombinant products, and 7 subjects receiving both recombinant and plasma products for previous courses of ITI. Four subjects received prior immunomodulatory therapy. The median (range) inhibitor titer at screening and historical peak were 11 (0.9–635) BU/mL and 127 (8–3000) BU/mL, respectively. During the 12 months prior to enrollment, the median (range) number of bleeds was 5 (0–24); 11 subjects used activated prothrombin complex concentrate (aPCC) for treatment of bleeds, 5 subjects received recombinant factor VIIa (rFVIIa), and 1 subject each received FVIII/von Willebrand factor, recombinant FVIII, and tranexamic acid. Twelve subjects received prophylaxis with bypassing agents during this period (10 aPCC, 1 rFVIIa, and 1 both products).

Conclusions:

This is the first prospective study describing rescue ITI with an extended half-life recombinant FVIII product. Enrolled subjects had multiple risk factors for poor ITI outcomes and a long duration of previous ITI. There is an unmet need for successful tolerization in such patients, allowing regular FVIII prophylaxis and potentially leading to improved clinical outcomes and quality of life.

Efficacy of on-demand treatment of bleeding episodes in hemophilia B patients with extended half-life N9-GP in pivotal trials: an in-depth analysis of treatment

Efficacy of on-demand treatment of bleeding episodes in hemophilia B patients with extended half-life N9-GP in pivotal trials: an in-depth analysis of treatment

Year: 2018
Grants:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
Author(s):
Christopher Walsh, David Cooper, Guy Young, Miguel Escobar

Objective:

N9-GP is a glycoPEGylated recombinant factor-IX (rFIX) product that provides approximately two times incremental recovery, five times half-life, and 10 times area under the plasma concentration-time curve compared with standard rFIX. Phase 3 single-dose (40 IU/kg) in adults showed incremental recovery 2.34 %/IU/kg and 17% mean FIX activity at 7 days. This analysis investigates N9-GP 40 IU/kg as a single-dose on-demand (OD) treatment for hemophilia B, focusing on predictors of a second dose.

Methods:

In the paradigm™2 pivotal trial of previously treated adult/adolescent patients (≤2% FIX), the FDA requested that a group receive OD treatment prior to US enrollment into prophylaxis. This case-by-case analysis evaluated OD treatment in relationship to bleed type/pattern and prestudy treatment regimen. Hemostatic efficacy was reported by patients on a 4-point scale.

Summary:

Fifteen patients were enrolled for OD treatment (13 severe, two moderate); 13 were previously treated OD and two with prophylaxis. Overall, 14/15 patients experienced 143 bleeds during 26 weeks, of which 120 (84%) in 13 patients were treated with one dose. Seven patients (five severe, two moderate) treated all bleeds (62) with one dose (36 ‘excellent’ and 26 ‘good’ response). The other seven patients, described below, experienced 58 bleeds (72%) treated with one dose (seven ‘excellent’, 49 ‘good’, one ‘moderate’, one not reported); their other 23 bleeds (28%) required ≥2 doses (17 ‘good’, six ‘moderate’). Two of these seven had 4/11 (36%) recurrent target joints (TJ) bleeds/rebleeds treated with additional doses. An 18-year-old previously treating with plasma-derived FIX (pdFIX), 76 IU/kg/bleed, had three right elbow TJ bleeds in two months treated with one, five, and two doses. A 27-year-old previously on prophylaxis (pdFIX 100 IU/kg every 3 days and 100 IU/kg/bleed) had two bleeds in a right ankle TJ in 2 weeks treated with two doses (including one for early rebleeding) and six doses prior to withdrawing from the study. Another four patients with bleeds requiring multiple doses had been historically treated with multiple high FIX doses (IU/kg x doses per bleed: 60×2, 80×2, 80×2, and 81×3) with prescribed dosing of 120, 160, 160, and 243 IU/kg/bleed; they reported 63 bleeds, of which 45 (71%) were treated with a single 40-IU/kg dose, 17 with two, and one with four doses. Average N9-GP dosing was 44.0, 74.7, 97.9, and 52.8 IU/kg/bleed (63%, 53%, 39%, and 78% reduction in FIX use per episode). The last patient was treated prestudy with 10 IU/kg/bleed had seven bleeds (six treated with one dose, mean 46.8 IU/kg/bleed).

Conclusions:

N9-GP 40 IU/kg was effective as a single-dose OD bleed treatment (84%). Additional dose(s) for some bleeds were associated with recurrent TJ bleeds in patients not on prophylaxis or patients previously taking multiple high doses for bleeding.

Achievement of therapeutic levels of factor VIII activity following gene transfer with valoctocogene roxaparvovec (BMN 270): Long-term efficacy and safety results in patients with severe hemophilia A

Achievement of therapeutic levels of factor VIII activity following gene transfer with valoctocogene roxaparvovec (BMN 270): Long-term efficacy and safety results in patients with severe hemophilia A

Year: 2018
Grants:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
Author(s):
Bella Madan, Benjamin Kim, Emily Symington, Fatemeh Tavakkoli, Glenn Pierce, John Pasi, Ke Yang, Michael Laffan, Savita Rangarajan, Will Lester, Wing Yen Wong

Objective:

As a single gene disorder of Factor VIII (FVIII), hemophilia A (HA) is an ideal candidate for gene therapy. We present results from an ongoing Phase 1/2 study of valoctocogene roxaparvovec (BMN 270; AAV5-FVIII-SQ) gene transfer in patients with severe HA.

Methods:

As of 16 April 2018, 13 subjects (6E13 vg/kg, n=7; 4E13 vg/kg, n=6) received a single intravenous dose of valoctocogene roxaparvovec, an AAV5 vector containing a B-domain-deleted FVIII gene. Safety, efficacy, immunogenicity, and other endpoints are being evaluated.

Summary:

FVIII activity is presented as median levels over 4-week intervals. In the 6E13 cohort, FVIII activity plateaued by Week 20 post-valoctocogene roxaparvovec, with median levels between Weeks 20-104 in the non-hemophilic range ([range] 46-122 IU/dL); Week 104 median FVIII activity was 46 IU/dL ([range] 6-145 IU/dL). In the 4E13 cohort, median [range] FVIII activity increased to just below the normal range (NR) at Week 52 [n=6]: 32 [3-59] IU/dL. Prior FVIII prophylaxis subjects had median [interquartile range, IQR] annualized FVIII infusions decline from 139 [122-157] (6E13) and 156 [126-183] (4E13) to 0 [0-0.4] and 0 [0-1] 4 weeks post-infusion through last follow-up; median [IQR] annualized bleeding rates post-infusion were 0 [0-0] in both cohorts (no bleeding episodes in 5 subjects in each cohort). Mild, grade 1, asymptomatic alanine aminotransferase (ALT) increases were reported in six of seven 6E13 and four of six 4E13 subjects; one 4E13 subject had a grade 2 ALT increase. Peak ALT levels ranged from 44-141 U/L (upper limit of normal=43 U/L). All subjects had a normal ALT level at last follow-up and all subjects were off of corticosteroid therapy. No subjects developed inhibitors to FVIII.

Conclusions:

Gene transfer with valoctocogene roxaparvovec in subjects with severe HA resulted in sustained, clinically relevant FVIII activity that reduced self-reported bleeding and exogenous FVIII use 2 years post-infusion in the 6E13 cohort. FVIII activity in the 4E13 cohort was maintained at the upper range of mild HA 1 year post-infusion. Both doses enabled achievement of long-term therapeutic levels of FVIII activity and prevention of hemophilia-related bleeding with a favorable safety profile.

A Multicenter, Retrospective Data Collection Study on the Compassionate Use of a Plasma-Derived Factor X Concentrate to Treat Patients with Hereditary Factor X Deficiency

A Multicenter, Retrospective Data Collection Study on the Compassionate Use of a Plasma-Derived Factor X Concentrate to Treat Patients with Hereditary Factor X Deficiency

Year: 2018
Grants:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
Author(s):
Chioma Akanezi, James N. Huang, Kaan Kavakli, Ri Liesner, Steven K. Austin

Objective:

Report results of an open-label international study that collected retrospective data on compassionate use of high-purity plasma-derived FX concentrate (pdFX) in subjects with hereditary factor X (FX) deficiency (FXD).

Methods:

This study included subjects with hereditary FXD (irrespective of severity) who received compassionate use pdFX as routine prophylaxis (RP), on-demand (OD) treatment, short-term prevention, and/or perisurgical hemostatic cover. Dosing was at the investigator’s discretion and tailored to each patient. Data from date of first compassionate use dose until data cutoff (31 December 2015) were collected retrospectively.

Summary:

All 15 enrolled subjects from 12 study centers received ≥1 pdFX dose for compassionate use. Of these, 13 subjects were aged ≥12 years (mean, 22.8 years) and 2 were aged <12 years, 8 (53.3%) were female, 12 (80.0%) were white, 3 (20.0%) were Asian. All subjects had moderate or severe FXD (FX activity [FX:C] <5 IU/dL).Of the 15 patients, 7 received only RP, 7 received only OD, and 1 alternated between OD and RP. The 8 subjects on RP received a total of 1239 RP infusions (mean, 154.9 infusions/subject, range 39–492), with a mean dose/infusion/subject of 32.5 IU/kg. The 2 subjects aged <12 years received larger RP doses than the 6 older subjects (mean doses/infusion/subject of 51.1 vs 26.3 IU/kg).Twelve subjects (8 OD, 4 RP; all aged ≥12 years) reported 88 bleeds (34 minor, 7 major, and 47 not rated); 37 bleeds were menorrhagic, 28 were traumatic, 17 were spontaneous, 4 were other, and 2 had unknown cause. pdFX efficacy was rated as effective for the 79 bleeds (including 1 subdural hematoma) treated with OD pdFX. Mean pdFX dose was 22.2 IU/kg/infusion/subject, with a mean of 9.5 infusions/subject to treat a bleed. More bleeds occurred in the OD than in the RP population.Two subjects underwent 1 dental procedure each, with only 1 presurgical pdFX dose required per patient; a third surgery, a portacath insertion, required 6 infusions to prevent postoperative bleeding. Two successful pregnancies/childbirths were also reported, with no abnormal bleeding complications or efficacy/safety concerns reported.The mean duration of compassionate use was 87.6 weeks for the 15 subjects, with a range of 15–211 weeks (0.3–4.0 years). Over the 1373 infusions administered across 25.2 subject-years, investigators rated overall pdFX efficacy as excellent in 14 (93.3%) subjects and good in 1 (6.7%) subject. No adverse drug reactions, safety concerns, infusion site reactions, tolerability issues, or inhibitor development were reported during pdFX compassionate use.

Conclusions:

The higher bleed rate in OD versus RP use and the treatment duration (up to 4 years) support the efficacy and safety of pdFX demonstrated in prospective clinical studies and its continued use in the treatment of subjects with hereditary FXD.

Efficacy, safety and pharmacokinetics of once-weekly prophylactic emicizumab (ACE910) in pediatric persons (<12 years) with hemophilia A with inhibitors: interim analysis of single-arm, multicenter, open-label, phase 3 study (HAVEN 2)

Efficacy, safety and pharmacokinetics of once-weekly prophylactic emicizumab (ACE910) in pediatric persons (<12 years) with hemophilia A with inhibitors: interim analysis of single-arm, multicenter, open-label, phase 3 study (HAVEN 2)

AWARDED/PRESENTED: 2017
GRANT/PROGRAM:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
RESEARCHERS:
Guy Young, Johannes Oldenburg, Ri Liesner, Victor Jiménez-Yuste, Maria Elisa Mancuso, Tiffany Chang, Marianne Uguen, Christophe Dhalluin, Christophe Schmitt, Sabine Fuerst-Recktenwald, Midori Shima, Rebecca Kruse-Jarres
Efficacy, safety and pharmacokinetics of emicizumab (ACE910) prophylaxis in persons with hemophilia A with inhibitors: randomized, multicenter, open-label, phase 3 study (HAVEN 1)

Efficacy, safety and pharmacokinetics of emicizumab (ACE910) prophylaxis in persons with hemophilia A with inhibitors: randomized, multicenter, open-label, phase 3 study (HAVEN 1)

Year: 2017
Grants:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
Author(s):
Johannes Oldenburg, Johnny Mahlangu, Benjamin Kim, Christophe Schmitt, Michael Callaghan, Guy Young, Elena Santagostino, Rebecca Kruse-Jarres, Claude Negrier, Craig Kessler, Nancy Valente, Elina Asikanius, Gallia Levy, Jerzy Windyga, Midori Shima

Objectives:

Emicizumab, a bispecific humanized monoclonal antibody in development to address unmet medical needs in persons with hemophilia A with inhibitors (PwHAwI), bridges FIXa and FX to replace the function of missing FVIIIa, needed for effective hemostasis. This study assessed efficacy, safety and PK of emicizumab prophylaxis in PwHAwI.

Methods:

Study NCT02622321 was conducted at 43 centers/sites, and enrolled PwHAwI ≥12 y.o. Participants (pts) receiving prior episodic bypassing agents (BPAs) were randomized (2:1) to emicizumab prophylaxis vs no prophylaxis (Arm A vs B). Primary endpoint compared treated bleed rates in Arm A vs B. PwHAwI receiving prior prophylactic BPA received emicizumab prophylaxis in Arm C. Emicizumab was injected subcutaneously at 3 mg/kg/wk for 4 wks, and 1.5 mg/kg/wk thereafter.

Summary:

109 male PwHAwI were enrolled; median age 28 (range 12–75) yrs. Median (range) emicizumab treatment exposure was 24.0 (3.0–47.9) wk overall and 29.5 (3.3–47.9) wk in Arm A. Statistically significant, clinically meaningful reductions (87%) in treated bleed rates were observed between emicizumab prophylaxis vs no prophylaxis (Arm A vs B) (annualized bleeding rate [95% confidence interval] 2.9 [1.69 to 5.02] versus 23.3 [12.33 to 43.89], P<0.0001), and in all secondary bleed-related endpoints (spontaneous, joint, target joint, and all bleeds). Of note, a 79% reduction in treated bleed rate was seen with emicizumab prophylaxis (Arm C) vs BPA prophylaxis prior to study entry in a non-interventional study (NCT02476942; intra-individual comparison, P=0.0003). Overall, 67.3% of PwHAwI on emicizumab prophylaxis had zero treated bleeds. Statistically significant, clinically meaningful improvements in health-related quality of life (HRQoL) and health status were seen for Arm A vs B. Emicizumab was well tolerated. Total of 198 adverse events (AEs) were reported in 103 pts; most common AEs were injection-site reactions (15%), and 12 serious AEs were reported in 9 (8.7%) pts. Thrombotic microangiopathy and thrombosis (2 pts each in primary analysis) were reported and associated with high cumulative aPCC doses averaging >100 U/kg daily for >24 hr prior to event onset. No events occurred with emicizumab prophylaxis alone. Both TMA events resolved once aPCC treatment was stopped, and the thrombotic events did not require anticoagulation; 2 pts resumed emicizumab without sequelae (1 with TMA, 1 with thrombosis). No antidrug antibodies were detected. Mean trough emicizumab concentrations >50 μg/mL were achieved after 4 loading doses (3 mg/kg/wk) and sustained with maintenance doses of 1.5 mg/kg/wk.

Conclusion:

Emicizumab prophylaxis prevented or substantially reduced bleeds in PwHAwI and meaningfully improved HRQoL. Emicizumab had acceptable safety without excess thrombotic risk in the absence of concomitant aPCC. PK levels were sustained with once- weekly maintenance doses. These promising data could support a paradigm shift in the management and lives of PwHAwI.

Estimating the prevalence of symptomatic, undiagnosed von Willebrand disease: analysis of medical insurance claims data

Estimating the prevalence of symptomatic, undiagnosed von Willebrand disease: analysis of medical insurance claims data

Year: 2017
Grants:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
Author(s):
Robert Sidonio, Ayesha Zia, Dana Fallaize

Objectives:

Von Willebrand disease (VWD) is a common inherited bleeding disorder, but awareness among healthcare professionals is low. Timely and proper diagnosis integral for reducing VWD burden, access to proper therapies, and avoidance of improper medication. Hence, we sought to estimate the prevalence of undiagnosed VWD among commercially insured patients in the United States with a recent history of bleeding events.

Methods:

Patients with a VWD diagnosis who were users of or candidates for von Willebrand factor were identified from the IMS PharMetrics Plus Database (2006─2015). We constructed a unary patient-finding model based on 12 prediagnosis variables that best defined this population, and applied to a set of undiagnosed patients with recent bleeding events from the same database. ‘Best fit’ (confidence level 5/6) and ‘good fit’ (confidence level 3/4) patients were identified. Prevalence of symptomatic undiagnosed VWD in the commercially insured population was estimated from the best-fit and good-fit population size (projection factor 10.4).

Summary:

Overall, 507 668 undiagnosed patients with recent bleeding events were identified (86% female, 14% male). Application of the VWD model identified 3318 best-fit and 37 163 good-fit patients; 91% of best-fit patients were females aged <46 years, with heavy menstrual bleeding the most common claim. Projection to the full commercially insured US population provided an estimate of 35 000 - 387 000 symptomatic, undiagnosed patients with VWD.

Conclusion:

There is a high prevalence of symptomatic, undiagnosed VWD (undiagnosed bleeding disorder patients that likely have VWD) in the commercially insured population. This data underscores the importance of improved disease education to both patients and the first line treaters, including OBGYN, emergency room, and pediatricians. Enhanced awareness of VWD symptoms and their impact, and of screening and testing procedures, may improve diagnosis of VWD and reduce the disease burden.

Physician practice patterns in the US show significant variation in how PK parameters are currently used to personalize care for US hemophilia A patients

Physician practice patterns in the US show significant variation in how PK parameters are currently used to personalize care for US hemophilia A patients

Year: 2017
Grants:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
Author(s):
Angela Forsyth, Josh Epstein, Tim Brown, Alessandro Gringeri, Elizabeth Schwartz, Jason Booth, Jimena Goldstine

Introduction & Objective:

Standard approaches to prophylaxis may be further improved by taking into account individuals’ pharmacokinetic (PK) profile, thereby increasing the likelihood of therapeutic success [Valentino 2012, Valentino 2014, Lissitckov 2017]. One study demonstrated an association between more time spent above higher FVIII levels (20 and 30%) and lower bleeding rates [Valentino 2016]. Furthermore, a consensus statement proposes to target specific factor levels to tailor treatment for different patient profiles [Iorio 2017]. Additionally, new extended half-life treatments provide physicians with another option to personalize therapy. As more data and therapeutic options become available, it is important to understand physicians’ current perceptions and practice patterns with respect to personalizing haemophilia A care in the US.

Materials & Methods:

Physicians in the US who treat persons with severe hemophilia A and provided informed consent were eligible to complete a cross-sectional, double-blinded web-based survey to evaluate physicians’ perceptions and practice patterns with respect to measuring PK and if/how they personalize FVIII treatment with this information, when and to what extent. This abstract presents results from the first half of the survey which focused on ways in which physicians measure FVIII pharmacokinetics and personalize care.

Results:

Ninety physicians completed the survey. The top three most important considerations for personalizing therapy in general were bleeding history, patient goals, and physical activity. The most commonly cited reason for conducting a PK assessment was product switch (74%) while the most common barrier was patient willingness/availability (60%). Physicians reported using a PK-based approach to personalize treatment in 25% (median) of their severe patients. Of physicians who use PK, trough levels (91%), half-life (58%), peak levels (56%) and Area Under the Curve (22%) were used. While 12% of these physicians reported using all PK parameters, 18% only used trough levels. 23% reported using peak, trough and half-life in combination. Most physicians (89%) indicated using PK data to adjust dose and 50% also used it as a patient education opportunity.

Conclusions:

There was significant variability across respondents as to how PK is assessed and how PK parameters are used in treatment decisions, suggesting an opportunity to increase awareness and use of PK-guided personalization to ultimately improve patient care. Additional education on the definitions and details of PK-guided dosing could help improve overall adoption of this treatment strategy and align the community on what it means to personalize therapy using PK information. More research studying the association between PK-guided prophylaxis and outcomes is encouraged to better understand how best to personalize PK-based prophylaxis for different patient scenarios.

An Integrated Safety and Efficacy Analysis of Sofosbuvir-Based Regimens in Patients with Hereditary Bleeding Disorders

An Integrated Safety and Efficacy Analysis of Sofosbuvir-Based Regimens in Patients with Hereditary Bleeding Disorders

AWARDED/PRESENTED: 2017
GRANT/PROGRAM:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
RESEARCHERS:
Christopher E. Walsh, Annette von Drygalski, Jordan J. Feld, Graham R. Foster, K. Rajender Reddy, Catherine Stedman, Kimberly Workowski, Nika Sajed, Frida Abramov, Gerald Crans, Robert H. Hyland, Luisa M. Stamm, Diana M. Brainard, John G. McHutchison, Gayle P. Balba, Edward J. Gane, Ira M. Jacobson
Efficacy, safety, and pharmacokinetics of a high-purity plasma-derived factor X (pdFX) concentrate in the prophylaxis of bleeding episodes in children <12 years with moderate to severe congenital factor X deficiency (FXD)

Efficacy, safety, and pharmacokinetics of a high-purity plasma-derived factor X (pdFX) concentrate in the prophylaxis of bleeding episodes in children <12 years with moderate to severe congenital factor X deficiency (FXD)

Year: 2017
Grants:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
Author(s):
Ri Liesner, Michael Gattens, Chioma Akanezi, Jeanette Payne

Background:

Congenital FXD is a rare bleeding disorder characterized by spontaneous joint and mucocutaneous bleeding and gastrointestinal or intracranial hemorrhage. pdFX is a US- and EU-approved treatment for congenital FXD, but data in children <12 years have been unavailable.

Aims:

To investigate pdFX efficacy, safety, and pharmacokinetics in children <12 years with moderate to severe congenital FXD.

Methods:

In this 6-month, open-label, multicenter, phase 3, prospective study in children <12 years, all subjects had a confirmed diagnosis of moderate to severe congenital FXD (basal FX:C <5%), severe bleeding history, or an F10 gene mutation causing a documented severe bleeding type. Subjects received routine prophylaxis at recommended 40–50 IU/kg twice weekly to maintain trough FX:C levels ≥5%. Each investigator assessed efficacy based on standardized criteria and presence of breakthrough bleeding. All subjects provided informed consent and the protocol was approved by appropriate independent ethics committees.

Results:

Mean age of the 9 trial completers was 6.8 years. Eight subjects had severe and 1 had moderate FXD. Overall, 537 prophylactic infusions were administered; mean dose/child was 38.6 IU/kg. Ten bleeds in 3 of 9 children were reported: 6 minor, 3 major, 1 unassessed. Investigators rated overall pdFX efficacy as excellent in all subjects. Overall mean incremental recovery was 1.74 IU/dL per IU/kg. FX trough levels were maintained >5% after visit 4 (days 29–42) in all subjects.

A total of 28 treatment-emergent adverse events (TEAEs) were reported in 8 children; none were considered pdFX related. No significant changes were noted in vital signs, physical exams, or laboratory measurements. No evidence of inhibitor development was seen.

Conclusion:

pdFX is efficacious in the prophylaxis of bleeding episodes in subjects <12 years with moderate to severe FXD. Safety profile in this population is consistent with previous results in subjects ≥12 years.

Funding: Bio Products Laboratory

Hereditary factor X (FX) deficiency in women and girls: treatment with a high purity plasma-derived factor X concentrate

Hereditary factor X (FX) deficiency in women and girls: treatment with a high purity plasma-derived factor X concentrate

Year: 2017
Grants:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
Author(s):
Roshni Kulkarni, Andra James, Miranda Norton, Amy Shapiro

Background:

A high-purity plasma-derived FX concentrate (pdFX) has been developed for treatment of hereditary FX deficiency, an autosomal recessive disorder.

Aim:

This post hoc analysis describes the pharmacokinetics, safety, and efficacy of pdFX in 10 women and girls with hereditary FX deficiency.

Methods:

In this open-label study, subjects (10 women/girls, 6 men/boys) aged ≥12 years with moderate or severe FX deficiency (basal plasma FX activity ≤5 IU/dL) were enrolled and received 25 IU/kg pdFX for on-demand treatment of bleeding episodes or preventative use for up to 2 years. All subjects provided informed consent and the protocol was approved by appropriate independent ethics committees.

Results:

Nine women and girls had severe and 1 had moderate FX deficiency, were aged 25.5 (median; range 14–58) y, and received a total of 267 pdFX infusions (178 for on-demand and 89 for preventative treatment). Men and boys (5 severe and 1 moderate FX deficiency) received a total of 159 pdFX infusions (64 on-demand; 95 preventative). The mean number of infusions per subject per month was higher among women and girls (2.48) than males (1.62). The mean pdFX incremental recovery was similar between women/girls and men/boys (2.05 vs 1.91 IU/dL per IU/kg, respectively), as was mean half-life (29.3 and 29.5 h, respectively). Among women and girls, 132 assessable bleeding episodes (61 heavy menstrual bleeding, 47 joint, 15 muscle, and 9 other) were treated with pdFX. Women and girls reported a treatment success rate (ie, subject rating of “excellent” or “good” response to pdFX) of 98%, comparable to the 100% treatment success rate among men and boys. After study completion, 2 subjects received pdFX for hemostatic cover during obstetric delivery. Additional infusion, bleed, and safety data will be presented.

Conclusion:

These results show that, in women and girls with moderate or severe hereditary FX deficiency, who experience reproductive tract and other bleeding events, pdFX was safe and effective. The pharmacokinetic profile of pdFX in women and girls was similar to that of men and boys.

Funding: Bio Products Laboratory

Updated results from a dose-escalation study in adults with severe or moderate-severe hemophilia B treated with AMT-060 (AAV5-hFIX) gene therapy: up to 1.5 years follow-up

Updated results from a dose-escalation study in adults with severe or moderate-severe hemophilia B treated with AMT-060 (AAV5-hFIX) gene therapy: up to 1.5 years follow-up

Year: 2017
Grants:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
Author(s):
Wolfgang Miesbach, Karina Meijer, Michel Coppens, Peter Kampmann, Robert Klamroth, Roger Schutgens, Giancarlo Castaman, Erhard Seifried, Joachim Schwaeble, Halvard Bonig, Christian Meyer, Federica Cattaneo, Eileen Sawyer, Frank Leebeek

Background:

Gene transfer for hemophilia offers the potential to convert the disease from a severe to mild phenotype with a single treatment. AMT-060 consists of an AAV5 vector containing a codon-optimized wildtype hFIX gene under control of a liver-specific promoter.

Objective:

This phase 1/2 study investigates the safety and efficacy of AMT-060 at 2 dose levels in adults with moderate-severe or severe hemophilia B.

Methods:

Multi-national, open-label, dose-escalating study in patients with factor IX (FIX) activity ≤2% of normal, and a severe bleeding phenotype (prophylactic exogenous FIX; or ondemand exogenous FIX, plus ≥4 bleeds/year or hemophilic arthropathy). Patients received either 5x1012 gc/kg (n=5) or 2×1013 gc/kg (n=5) of AMT-060 iv. Efficacy assessments include endogenous FIX activity (measured ≥10 days after use of exogenous FIX); reduction of exogenous FIX use; and annualized spontaneous bleeding rates. Safety assessments include treatment related adverse events, immunological and inflammatory biomarkers.

Summary:

There were no screening failures due to AAV5 neutralizing antibodies. Mean FIX activity in the lower dose cohort was 5.2% (min-max, 3.0-6.8%; n=4; 1 patient remaining on prophylaxis excluded) during 1 year of follow-up, and 6.9% (min-max, 3.1-12.7%; n=5) in the higher dose cohort during 26 weeks follow-up. Eight of 9 patients on FIX prophylaxis discontinued use after AMT-060 infusion. Follow-up to up to 1.5 years will be presented, with annualized reduction of exogenous FIX use and spontaneous bleeding rates. Mild, temporary elevations in ALT were observed in 3 patients with higher mean FIX activity (6.3-12.7%; 1 in the lower and 2 in the higher dose cohort). Each received a tapering course of prednisolone. ALT elevations were not associated with changes in FIX activity or a capsid-specific T-cell response.

Conclusions:

Patients continue to show sustained clinical benefit and endogenous FIX activity with no T-cell activation ≥1 year after a single infusion of AMT-060.

An Evaluation of the Switch from Standard Factor VIII Prophylaxis to Prophylaxis with an Extended Half-Life, Pegylated, Full-length Recombinant Factor VIII (BAX 855)

An Evaluation of the Switch from Standard Factor VIII Prophylaxis to Prophylaxis with an Extended Half-Life, Pegylated, Full-length Recombinant Factor VIII (BAX 855)

Year: 2015
Grants:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
Author(s):
Oleksandra Stasyshyn, Ralph Gruppo, Barbara Konkle, Tung Wynn, Marilyn Manco-Johnson, Pratima Chowdary, Vladimir Komrska, Laimonas Griskevicius, Elaine Eyster, Krzysztof Chojnowski, Werner Engl, Lisa Patrone, Brigitt Abbuehl

Objective:

This report assesses the changes in bleeding patterns as previously treated severe hemophilia A patients were switched from their pre-study standard factor VIII (FVIII) prophylactic treatment regimen to prophylaxis with BAX 855 - an extended half-life, pegylated, full-length recombinant FVIII built on ADVATE - during their participation in the pivotal trial.

Methods:

Patients’ informed consent and appropriate ethics committee approvals were obtained. At baseline, eligible patients reported their pre-study treatment regimen and average annualized bleeding rate (ABR) for the previous 3-6 months. Patients assigned to the prophylactic arm were to receive 45±5 IU/kg of BAX 855 twice weekly for ≥50 exposure days or approximately 6 months. This per-protocol analysis included 101 treated patients in the prophylactic arm.

Summary:

The overall mean (SD) ABR for these treated patients was 3.7 (4.7), which was lower than the ABR for the 17 patients treated on-demand during the study (40.8 [16.3] - who were all treated on-demand pre-study). Of the 101 subjects in BAX 855 prophylactic arm, 82 were treated on prophylaxis and 19 were treated on-demand during the pre-study period. The BAX 855 prophylactic dosing frequency was reduced by a mean (SD) of 26.7% (27.9) compared to the frequency reported in the pre-study period, which is approximately equivalent to one less prophylactic infusion per week when using BAX 855 for prophylaxis. The mean dose per prophylactic infusion was higher for the BAX 855 treatment regimen compared to pre-study (44.53 vs 38.12 IU/kg), but FVIII consumption per week was lower during the study compared to pre-study (83.96 vs 97.79 IU/kg/week). More patients treated on BAX 855 prophylaxis during the study treatment period had zero bleeding episodes compared to during their pre-study period: 37.8% vs 23.2%. The mean ABR was lower for subjects on BAX 855 prophylaxis compared to pre-study: 4.13 vs 9.74.

As expected, the 19 patients treated on-demand pre-study had a higher mean ABR (31.53) and all experienced bleeding (ie, none had zero hemarthroses during the pre-study period) compared to during their BAX 855 prophylactic treatment period (mean ABR of 1.68 and 47.4% had zero bleeding episodes).

Conclusions:

These results further demonstrate the benefit of BAX 855 prophylaxis (45±5 IU/kg twice weekly) and support its efficacy profile for the prevention of bleeding when used twice weekly, which suggests that fewer infusions may be needed to maintain prophylactic efficacy.

Low Annualized Bleeding Rates in Phase 3 Studies of Recombinant Factor VIII Fc Fusion Protein (rFVIIIFc) in Subjects with Target Joints at Baseline

Low Annualized Bleeding Rates in Phase 3 Studies of Recombinant Factor VIII Fc Fusion Protein (rFVIIIFc) in Subjects with Target Joints at Baseline

Year: 2015
Grants:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
Author(s):
Michael Wang, Beatrice Nolan, Guy Young, Savita Rangarajan, Bryce Kerlin, Roshni Kulkarni, Margaret V. Ragni, Ross I. Baker, Elisa Tsao, Desilu Glazebrook, Glenn Pierce, Geoffrey Allen

Introduction and Objectives:

The phase 3 A-LONG and Kids A-LONG studies demonstrated the safety and efficacy of rFVIIIFc for the control and prevention of bleeding episodes in subjects with severe hemophilia A. This subgroup analysis of A-LONG and Kids A-LONG examined bleeding frequency with rFVIIIFc prophylaxis in subjects with target joints at baseline.

Methods:

A-LONG (≥12 y) and Kids A-LONG (<12 y) subjects with a history of target joints (a major joint with ≥3 bleeding episodes in a 6-month period) who were previously treated with FVIII and received on-study rFVIIIFc prophylaxis were identified. Self-reported pre-study 12- month bleeding history and on-study annualized bleeding rate (ABR) for all bleeds were evaluated.

Results:

93/141 subjects in A-LONG and 13/69 subjects in Kids A-LONG had target joints at baseline. The most prevalent locations of pre-study target joints identified at baseline among subjects in A-LONG were the elbow (61.7%) and ankle (59.6%). Similarly, in Kids A-LONG, these were the ankle (69.2%) and elbow (30.8%). A total of 59.7% and 52.4% of subjects receiving individualized (Arm 1) and weekly (Arm 2) rFVIIIFc prophylaxis in A-LONG, respectively, and 53.8% of subjects receiving rFVIIIFc prophylaxis in Kids A-LONG with target joints at baseline had no target joint bleeding episodes on-study. Median on-study ABRs with rFVIIIFc prophylaxis tended to be lower than pre-study bleeding rates in subjects with target joints at baseline (Table).

Conclusions:

For subjects with severe hemophilia A who had target joints at baseline, rFVIIIFc prophylaxis lowered bleeding rates across age groups compared with pre-study FVIII treatment.

Table. Median (Interquartile Range) Pre-study and On-study Bleeding Rates in Subjects Receiving On- study rFVIIIFc Prophylaxis With Target Joints at Baseline

 

Efficacy of a Recombinant Factor IX Investigational Product, IB1001 (trenonacog alfa) for Perioperative Management in Hemophilia B Patients

Efficacy of a Recombinant Factor IX Investigational Product, IB1001 (trenonacog alfa) for Perioperative Management in Hemophilia B Patients

Year: 2015
Grants:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
Author(s):
Bojan Drobic, Yi Hua, Tim Babinchak, Edward Gomperts

Objective:

To evaluate efficacy of IB1001 for perioperative management of bleeding under surgical circumstances in hemophilia B patients.

Methods:

The efficacy of IB1001 for perioperative management has been evaluated in a prospective, open-label, multicenter international study where 17 subjects (16 male PTPs and one female hemophilia B carrier) underwent 20 major surgical procedures. The PTPs were defined as patients with a minimum of 150 exposures to another factor IX preparation. The subjects had severe or moderately severe (factor IX level ≤ 2 IU/dL) hemophilia B without inhibitors, with exception of one mild hemophilia B female carrier. Efficacy of IB1001 was based on the surgeon’s assessment including estimation of blood loss as ‘less than expected’, ‘expected’, or ‘more than expected’ at the time of surgery and assessment of hemostasis at 12 and 24 hours post-surgery as ‘superior’, ‘adequate’, or ‘poorly controlled’. Transfusion requirements were also monitored.

Summary:

Thirteen major procedures in 12 male subjects were managed by bolus regimen, and 6 major procedures in 4 male subjects were managed by continuous infusion regimen. Mean loading dose for 13 major procedures managed by bolus regimen was 120 ± 11.4 IU/kg and mean maintenance bolus dose (given every 12 hours) was 59.7 ± 12.2 IU/kg. During the 24 hours following surgery, factor IX levels were successfully maintained over 60%, as intended. Factor IX levels at pre-infusion were 59.7% ± 15.9% at 12 hours after surgery and 54.4% ± 16.5% at 24 hours after surgery. For a major procedure in one female carrier, the bolus dose was 110 IU/kg, while the mean maintenance dose was 44.9 ± 7.0 IU/kg. Mean loading dose for 6 major procedures managed by continuous infusion regimen was 95.4 ± 14.5 IU/kg and the mean maintenance infusions were 7.1 ± 4.0 IU/kg/hr. In all major procedures, blood loss at the time of surgery was ‘expected’ or ‘less than expected’ as assessed by the surgeon. IB1001 was rated by the surgeon as ‘superior’ or ‘adequate’ in controlling hemostasis post-surgery, including 8 knee arthroplasties, two elbow arthroplasties, one knee amputation, one percutaneous Achilles tendon lengthening, one open inguinal hernia repair, one tibiotalar fusion, two arthroscopic synovectomies, three debridements and one total hysterectomy/bilateral oopherectomy. There were no transfusions required perioperatively.

Conclusions:

At the time of surgery, blood loss was expected or less than expected after IB1001 treatment, while post-surgery effective hemostasis control was achieved following IB1001 treatment in hemophilia B patients.

Efficacy of a Recombinant Factor IX Investigational Product, IB1001 (trenonacog alfa) in Previously Treated Patients with Hemophilia B

Efficacy of a Recombinant Factor IX Investigational Product, IB1001 (trenonacog alfa) in Previously Treated Patients with Hemophilia B

Year: 2015
Grants:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
Author(s):
Bojan Drobic, Yi Hua, Tim Babinchak, Edward Gomperts

Objective:

To evaluate efficacy of IB1001 with respect to breakthrough bleeding during prophylaxis and with respect to control of hemorrhaging in prophylaxis and on-demand treatment regimens in previously treated patients (PTPs) with hemophilia B.

Methods:

The efficacy of IB1001 has been evaluated in a prospective, open-label, uncontrolled multicenter international study in which a total of 68 male PTPs between 7 and 64 years of age received IB1001 either as prophylaxis or on-demand treatment. All subjects had severe or moderately severe (factor IX level ≤ 2 IU/dL) hemophilia B without inhibitors. There were 61 subjects who received prophylaxis [predominantly secondary or tertiary prophylaxis as defined by World Federation of Hemophilia (WFH) guidelines] and 12 were treated on-demand during the study conduct. Both, the subjects and the study investigators rated the efficacy of IB1001 in management of bleeding episodes.

Summary:

The mean number of exposure days (ED) was 138.2 (median: 127.5 ED), including 55 subjects with ≥ 50 ED and 45 subjects with ≥ 100 ED. Subjects on prophylaxis received a mean intravenous dose of 55.0 ± 12.8 IU/kg IB1001 twice weekly, while subjects in the on- demand regimen received a mean dose of 60.0 ± 18.2 IU/kg IB1001. In the prophylaxis group, median annualized bleed rate (ABR) was 1.52, and in the on-demand group, median ABR was 16.39. There were 19/61 (31.1%) subjects on IB1001 prophylaxis who reported no bleeding episodes. A total of 508 bleeding episodes were treated with IB1001; 286 bleeds were recorded for patients on prophylaxis and 222 in the on-demand regimen. Majority of the bleeds (70.9%) resolved after a single IB1001 infusion, while 13% of the bleeds required two infusions. A minority of the bleeds (4.7%) required 5 or more infusions; these bleeds were predominantly related to trauma, target joints and/or muscle bleeds. Subjects rated efficacy of IB1001 as ‘excellent’ or ‘good’ in 84% of all treated bleeding episodes. Of 414 subject visits where the efficacy of IB1001 was evaluated by the study investigators, 92% were rated as ‘effective’ in prevention and treatment of bleeding by IB1001.

Conclusions:

IB1001 is effective for the treatment of hemophilia B either as secondary or tertiary prophylaxis or on an episodic (on-demand) basis. Based on clinical trial data, IB1001 is effective in controlling breakthrough or episodic bleeding episodes.

Recombinant von Willebrand factor in severe von Willebrand disease: a prospective clinical trial

Recombinant von Willebrand factor in severe von Willebrand disease: a prospective clinical trial

Year: 2015
Grants:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
Author(s):
Joan C. Gill, Giancarlo Castaman, Jerzy Windyga, Peter Kouides, Margaret Ragni, Frank W.G. Leebeek, Ortrun Obermann-Slupetzky, Miranda Chapman, Sandor Fritsch, Borislava G. Pavlova, Isabella Presch, Bruce Ewenstein

Objectives:

This trial evaluated the hemostatic efficacy, pharmacokinetics, and safety of a recombinant VWF (rVWF) in adults with severe von Willebrand disease (VWD) (type 3 [VWF:Ag ≤ 3 IU/dL], severe type 1 [VWF:RCo< 20 IU/dL], 2A [VWF:RCo< 20 IU/dL], 2N [FVIII:C<10% ], 2B, or 2M).

Methods:

Bleeds were to be treated initially with rVWF and rFVIII (1.3:1 ratio), followed by rVWF alone (as long as FVIII:C >40%). Hemostatic efficacy was evaluated using a pre- defined 4-point rating scale (none=4, moderate=3, good=2, excellent=1). PK parameters for rVWF vs. rVWF:rFVIII were assessed in a randomized crossover design, and a 6-month repeated PK evaluation for rVWF alone.

Summary:

Of 31 subjects assigned to bleed treatment, 22 (17 type 3, 4 type 2A and 1 type 2N) experienced 192 bleeding episodes (several in multiple locations) that were treated with rVWF: 106 occurred in mucosal tissue (including 32 menorrhagic, 42 nasopharyngeal, 26 mouth/oral bleeds), 59 joint bleeds, 6 gastrointestinal bleeds, and 37 in other locations. Treatment success (mean efficacy rating <2.5) was achieved in all 22 subjects (100%; Clopper-Pearson exact 90% confidence interval: 87.3 to 100.0). ‘Excellent’ ratings were given for 186/192 (96.9%) bleeds (119/122 minor, 59/61 moderate, 6/7 severe, 2/2 unknown severity) and the remaining 3.1% were ‘good’. One infusion was effective in 81.8% of bleeds (median [range]: 1 [1-4] overall; 2 [1-3] for severe bleeds). The subject’s own assessment of treatment efficacy (an exploratory endpoint), was ‘excellent’ within 8 hours after the first infusion for 125/134 (93.3%), ‘good’ for 8/134 (6.0%) and ‘moderate’ for 1/134 (0.7%) bleeding episodes. A substantial increase in FVIII:C and sustained stabilization (> 40% by 6 hours, rising to >80% 24 hours post-infusion) was observed after infusion with rVWF. PK parameters for VWF Ristocetin cofactor (VWF:RCo, a surrogate for the platelet-dependent function of rVWF) were similar when rVWF was infused alone (mean T1/2 21.9 h vs. 19.6 h with rVWF:rFVIII). Eight adverse events (tachycardia, infusion site paraesthesia, ECG t wave inversion, dysgeusia, generalized pruritis, hot flush, chest discomfort and increased heart rate) in 5 subjects were assessed as related to rVWF. No inhibitor or anti-VWF binding antibody development was observed, and there were no thrombotic events or severe allergic reactions.

Conclusions:

rVWF was safe, well-tolerated and effective in the treatment of a variety of bleeding presentations in severe VWD. The sustained stabilization in FVIII:C after the initial infusion enables subsequent infusion of rVWF without rFVIII, when multiple infusions are required.

Pegylated full-length recombinant factor VIII (BAX 855) for prophylaxis in previously treated adolescent and adult patients with severe hemophilia A

Pegylated full-length recombinant factor VIII (BAX 855) for prophylaxis in previously treated adolescent and adult patients with severe hemophilia A

Year: 2015
Grants:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
Author(s):
Ralph Gruppo, Brian Wicklund, Barbara K. Konkle, Oleksandra Stasyshn, Pratima Chowdary, Brigitt E. Abbuehl, Werner Engl, Lisa Patrone, Bruce Ewenstein

Objective:

To assess the pharmacokinetics (PK) and efficacy of prophylactic treatment with BAX 855 - a novel polyethylene glycol (peg)ylated full-length recombinant factor VIII, built on the rAHF-PFM (ADVATE) protein - by age group in previously-treated male patients with severe hemophilia A.

Methods:

Adolescent (12 to <18 years) and adult (18 to 65 years) subjects received 45 ± 5 IU/kg BAX 855 twice weekly as prophylaxis for approximately 6 months. PK was assessed in a subgroup (n=25 planned, including ≥6 adolescents) for one ADVATE infusion, then for BAX 855 at the initial infusion and after ≥50 exposure days (EDs). Efficacy was assessed in all subjects.

Summary:

Twenty-six subjects (8 adolescents, 18 adults) were included in the PK evaluation, and 121 (23 adolescents, 98 adults) were included in the efficacy analysis (all subjects assigned to treatment, i.e. full analysis set). The extended half-life (T1/2) and mean residence time (MRT) of BAX 855 (initial dose) compared to ADVATE were demonstrated by fold increases in the means of 1.4 and 1.5, respectively in both adolescents and in adults, using the one-stage clotting assay. The initial and repeat PK assessments of BAX 855 showed similar results. Consistent trends were observed when PK was determined using the chromogenic assay. The arithmetic mean (SD) annualized bleeding rate (ABR) during prophylaxis with BAX 855 was higher in adolescents than in adults (6.2 [6.1] versus 3.2 [4.2]). ABRs for injury-related bleeding episodes (BEs) were higher in adolescents (arithmetic mean [SD]:2.3 [3.2] versus 1.7 [3.1] in adults), thus contributing to the overall higher ABR in this group. Joint ABRs were lower in adolescents (arithmetic mean [SD]: 1.8 [2.5] versus 3.2 [8.8] in adults) with an inverse relationship for non-joint ABRs. Six adolescents (26.1%) and 39 adults (40.2%) had zero BEs. A total of 48 BEs occurred in adolescents (20 minor; 26 moderate; 2 severe); 182 occurred in adults (69 minor; 103 moderate; 10 severe). The hemostatic efficacy of BAX 855 was rated excellent or good at resolution for the majority of BEs in both age groups (93.8% in adolescents; 92.9% in adults).

Conclusions:

Although fewer adolescents than adults were included in the study, the data suggest that BAX 855 is efficacious in both age groups for twice-weekly prophylaxis and control of BEs. As expected, joint ABR was higher in the adult group.

Long-term safety and efficacy of recombinant factor VIII Fc (rFVIIIFc) for the treatment of severe hemophilia A: United States subgroup interim analysis of the ASPIRE study

Long-term safety and efficacy of recombinant factor VIII Fc (rFVIIIFc) for the treatment of severe hemophilia A: United States subgroup interim analysis of the ASPIRE study

Year: 2015
Grants:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
Author(s):
Doris Quon, Guy Young, Margaret Ragni, Barbara Konkle, Roshni Kulkarni, Amy Shapiro, Elisa Tsao, Lynda Cristiano, Geoffrey Allen

Objective:

The ongoing rFVIIIFc extension study, ASPIRE (clinicaltrials.gov #NCT01454739), evaluates the long-term safety and efficacy of rFVIIIFc in adults, adolescents, and children with severe hemophilia A. Here we report interim outcomes for United States (US) subjects in ASPIRE.

Methods:

Eligible subjects could enroll in ASPIRE upon completing A-LONG or Kids A-LONG. There were 4 treatment groups: individualized prophylaxis (25-65 IU/kg every 3-5 days, or 20-65 IU/kg on D1, 40-65 IU/kg on D4 if twice weekly); weekly prophylaxis (65 IU/kg every 7 days); modified prophylaxis (to further personalize and optimize treatment when needed); or episodic treatment. Subjects could change treatment groups at any time. Subjects <12 yrs participated only in individualized and modified prophylaxis groups. Primary endpoint: development of inhibitors. Secondary outcomes included annualized bleeding rate (ABR) and rFVIIIFc exposure days (EDs).

Summary:

Sixty subjects (49 from A-LONG; 11 from Kids A-LONG) enrolled. As of the interim data cut (6 Jan 2014), the median time on ASPIRE was 80.37 (A-LONG) and 15.94 (Kids A-LONG) wks; 82% (A-LONG) and 27% (Kids A-LONG) of subjects had ≥100 cumulative rFVIIIFc EDs. 7/49 A-LONG subjects changed treatment groups upon enrollment into or during ASPIRE; 2 Kids A-LONG subjects switched from individualized to modified prophylaxis upon enrollment into ASPIRE. Median ABRs were low with rFVIIIFc prophylaxis (Table). Overall, most subjects treated prophylactically during the parent study did not experience changes to their total weekly prophylactic dose or dosing interval during ASPIRE. For subjects who enrolled from A-LONG and Kids A-LONG, 94% and 100% of all bleeding episodes during ASPIRE, respectively, were controlled with 1 infusion. In the overall study population, no inhibitors were observed during ASPIRE; adverse events were typical of the general adult and pediatric hemophilia A populations.

Conclusion:

Interim data from US subjects in ASPIRE are consistent with those of the phase 3 parent studies and the overall ASPIRE interim analysis. Results from ASPIRE confirm the longer-term safety of rFVIIIFc and the maintenance of a low ABR with extended interval prophylactic dosing in individuals with severe hemophilia A.

 

Table. ABR in US subjects during ASPIRE, by parent study

Increase or Maintenance of Physical Activity in Patients Treated with Recombinant Factor IX Fc Fusion Protein (rFIXFc) in the B-LONG and Kids B-LONG Studies

Increase or Maintenance of Physical Activity in Patients Treated with Recombinant Factor IX Fc Fusion Protein (rFIXFc) in the B-LONG and Kids B-LONG Studies

Year: 2015
Grants:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
Author(s):
Amy Shapiro, Roshni Kulkarni, Jerzy Windyga, Margaret Ragni, John Pasi, Margareth Ozelo, Elisa Tsao, Geoffrey Allen, Baisong Mei

Introduction and Objectives:

In the phase 3 B-LONG and Kids B-LONG studies, subjects with severe hemophilia B receiving rFIXFc prophylaxis had low annualized bleeding rates (ABRs), with decreased weekly factor consumption and fewer infusions compared with pre- study FIX treatment. This report evaluated the effect of rFIXFc on subjects’ physical activity across a variety of age groups using a subject-reported assessment.

Methods:

Eligible subjects for B-LONG (≥12 y) and Kids B-LONG (<12 y) were previously treated males with severe hemophilia B (≤2 IU/dL endogenous FIX activity). Subjects in B- LONG were enrolled into 1 of 4 treatment arms: Arm 1, weekly prophylaxis; Arm 2, individualized interval prophylaxis; Arm 3, episodic treatment; or Arm 4, perioperative management (not included in this analysis). All subjects in Kids B-LONG started on weekly prophylaxis. There were no restrictions regarding physical activity. Physical activity assessments were conducted at Weeks 4, 16, 26, 39, 52, and end of study (B-LONG) and Weeks 3, 12, 24, 36, 50, and end of study (Kids B-LONG). At each visit after their first rFIXFc dose, subjects were asked to rate their activity level relative to their prior study visit as: more (or more intensive), fewer (or less intensive), or about the same amount of physical activities. To summarize each subject’s change in physical activity over the course of the study compared to baseline, subjects’ reports were classified into four groups: less, the same, more, or undetermined.

Results:

Overall, 123 and 30 subjects enrolled in B-LONG and Kids B-LONG, respectively. The majority of subjects in B-LONG reported more or the same amount of physical activity, and few subjects reported less physical activity during the study (less, the same, more, undetermined in Arm 1 [n=60], 7%, 42%, 35%, 17%; Arm 2 [n=25], 16%, 28%, 48%, 8%; Arm 3 [n=27], 15%, 26%, 30%, 30%, respectively). Results were generally similar for subjects in Kids B-LONG (for subjects aged <6 y [n=15], 13%, 27%, 47%, 13%; for subjects aged 6 to <12 y [n=15], 7%, 13%, 67%, 13%).

Conclusions:

ABRs were low in B-LONG and Kids B-LONG despite similar or increased physical activity levels reported by the majority of subjects. These results suggest that people with severe hemophilia B across a variety of age groups may maintain or increase their physical activity levels with rFIXFc, while also reducing infusion frequency and weekly factor consumption, without compromising efficacy.

Patients Treated with Recombinant Factor VIII Fc Fusion Protein (rFVIIIFc) Reported Increased or Maintained Physical Activity in the A-LONG and Kids A-LONG Studies

Patients Treated with Recombinant Factor VIII Fc Fusion Protein (rFVIIIFc) Reported Increased or Maintained Physical Activity in the A-LONG and Kids A-LONG Studies

Year: 2015
Grants:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
Author(s):
Doris Quon, Robert Klamroth, Roshni Kulkarni, Amy Shapiro, Ross Baker, Giancarlo Castaman, Bryce Kerlin, Elisa Tsao, Geoffrey Allen

Introduction and Objectives:

In the phase 3 A-LONG and Kids A-LONG studies, subjects with severe hemophilia A receiving rFVIIIFc prophylaxis 1-2 times/week had low annualized bleeding rates (ABRs), with comparable pre-study and on-study weekly factor consumption for subjects previously on FVIII prophylaxis. This report evaluated the effect of rFVIIIFc on subjects’ physical activity across a variety of age groups using a subject-reported assessment.

Methods:

Subjects eligible for A-LONG (≥12 y) and Kids A-LONG (<12 y) were previously treated males with severe hemophilia A (<1 IU/dL endogenous FVIII activity). Subjects in A- LONG were enrolled into 1 of 3 arms: Arm 1, individualized prophylaxis; Arm 2, weekly prophylaxis; or Arm 3, episodic treatment. All subjects in Kids A-LONG received rFVIIIFc prophylaxis. There were no restrictions regarding physical activity. Physical activity assessments were conducted at Weeks 7, 14, 28, 38, 52, and end of study (A-LONG) and Weeks 2, 7, 12, 17, 22, 26, and end of study (Kids A-LONG). At each visit after their first rFVIIIFc dose, subjects were asked to report any changes in their activity levels relative to their prior study visit as: more (or more intensive), fewer (or less intensive), or about the same amount of physical activities. To summarize each subject’s change in physical activity during the study compared to baseline, subjects’ reports were classified into four groups: less, the same, more, or undetermined.

Results:

A total of 165 and 71 subjects enrolled in A-LONG and Kids A-LONG, respectively. Overall, the majority of subjects in A-LONG reported more or the same amount of physical activity, and few subjects reported less physical activity during the study (less, the same, more, undetermined in Arm 1 [n=117], 8%, 36%, 51%, 5%; Arm 2 [n=23], 9%, 48%, 39%, 4%; Arm 3 [n=23], 9%, 52%, 26%, 13%, respectively). Results were generally similar for subjects in Kids A-LONG (for subjects aged <6 y [n=35], 3%, 26%, 66%, 6%; for subjects aged 6 to <12 y [n=34], 9%, 26%, 56%, 9%).

Conclusions:

The majority of subjects in A-LONG and Kids A-LONG reported similar or increased physical activity levels during the studies, while maintaining low ABRs. These self- reported data suggest that subjects across a variety of age groups with severe hemophilia A who are transitioning to rFVIIIFc may maintain or increase physical activity levels, while reducing infusion frequency and maintaining similar weekly factor consumption, without compromising efficacy.

SPINART 3-Year Analyses: Patient- and Joint-Level Changes in Colorado Adult Joint Assessment Scale and Magnetic Resonance Imaging Scores With Bayer’s Sucrose-Formulated Recombinant Factor VIII (rFVIII-FS) in Adolescents and Adults

SPINART 3-Year Analyses: Patient- and Joint-Level Changes in Colorado Adult Joint Assessment Scale and Magnetic Resonance Imaging Scores With Bayer’s Sucrose-Formulated Recombinant Factor VIII (rFVIII-FS) in Adolescents and Adults

Year: 2015
Grants:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
Author(s):
Sharon Funk, Björn Lundin, Walter Hong

Introduction:

Efficacy and safety of routine prophylaxis vs on-demand treatment with Bayer’s sucrose-formulated recombinant factor VIII (rFVIII-FS) in patients with severe hemophilia A were evaluated in the randomized, controlled SPINART study.

Aim:

Patient- and joint-level changes at year 3 in magnetic resonance imaging (MRI) and Colorado Adult Joint Assessment Scale (CAJAS) scores were compared to investigate if individual joint data revealed results that may have been obscured in previously reported patient-level analyses.

Methods:

SPINART included males aged 12–50 years with severe hemophilia A, ≥150 exposure days to FVIII, no inhibitors, and no prophylaxis for >12 months in the past 5 years. Patients were randomized 1:1 to rFVIII-FS on demand or prophylaxis (25 IU/kg 3x/wk). Changes from baseline to year 3 were evaluated for 6 index joints (knees, ankles, elbows) using the Extended MRI (eMRI) scale and CAJAS. Percentages of patients or joints with improved, unchanged, or worsened scores were evaluated.

Summary:

Of the 84 patients in SPINART, eMRI and CAJAS change from baseline data were available for 62 (prophylaxis, n=32; on demand, n=30) and 76 patients (n=39; n=37) and for 386 (n=197; n=189) and 446 joints (n=224; n=222), respectively. Categoric analysis of CAJAS data at year 3 showed a higher percentage of patients treated prophylactically vs on demand with improved scores (64.1% vs 43.2%) and a lower percentage with worsened scores (28.2% vs 51.4%); with eMRI, the percentage improved was smaller (12.5% vs 6.7% improved; 75.0% vs 73.3% worsened). At individual joints, improved, unchanged, and worsened CAJAS scores in patients treated with prophylaxis vs on demand were 46.0% vs 33.3%, 22.3% vs 24.3%, and 31.7% vs 42.3%; eMRI values were 8.1% vs 3.7%, 61.9% vs 69.8%, and 29.9% vs 26.5%.

Conclusions:

These data suggest that in adults and adolescents with severe hemophilia A, joint function as measured by CAJAS is more likely to improve after 3 years of routine prophylaxis with rFVIII-FS than joint structure as measured by MRI.

Interim results of the B-YOND study evaluating long-term safety and efficacy of recombinant factor IX Fc (rFIXFc) in children with severe hemophilia B

Interim results of the B-YOND study evaluating long-term safety and efficacy of recombinant factor IX Fc (rFIXFc) in children with severe hemophilia B

Year: 2015
Grants:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
Author(s):
Carolyn Bennett, Beatrice Nolan, Roshni Kulkarni, Kathelijn Fischer, David Perry, Christopher Barnes, Huixing Yuan, Alejandra Ramirez-Santiago, Glenn F Pierce, Baisong Mei

Objective:

The ongoing rFIXFc extension study, B-YOND (clinicaltrials.gov #NCT01425723) , evaluates the long-term safety and efficacy of rFIXFc for the treatment of severe hemophilia B. Here we report interim safety and efficacy data for children aged <12 yrs enrolled in B- YOND.

Methods:

Upon completing Kids B-LONG, eligible subjects could enroll in one of the 3 prophylactic treatment groups in B-YOND: weekly (20 to 100 IU/kg every 7 days), individualized (100 IU/kg every 8 to 16 days, or twice monthly), or modified (a prophylaxis regimen different from weekly or individualized prophylaxis). Subjects could change treatment groups at any point in the study. The primary endpoint was development of inhibitors. Secondary outcomes included annualized bleeding rate (ABR) and rFIXFc exposure days (EDs).

Summary:

At the time of the interim data cut (17 October 2014), 23 subjects had completed Kids B-LONG; all enrolled in B-YOND (<6 yrs of age cohort, n=9; 6 to <12 yrs of age cohort, n=14). As of the interim data cut, 2 subjects had completed and 21 subjects continued in B-YOND (median time on study: 47.7 weeks). From the start of Kids B-LONG to the B-YOND interim data cut, the median time on rFIXFc was 95.3 weeks, with a median of 94 cumulative rFIXFc EDs. All subjects were on weekly prophylaxis in Kids B-LONG; 5 subjects changed treatment groups at the start of or during B-YOND. In the weekly prophylaxis group, the median (IQR) average weekly prophylactic dose was 64 (52, 66) IU/kg and 63 (59, 64) IU/kg in the <6 yrs and 6 to <12 yrs of age cohorts, respectively. The median (IQR) dosing interval among subjects on individualized prophylaxis was 10 (10, 11) days. As of the interim data cut, no inhibitors were observed, there were no reports of anaphylaxis or serious hypersensitivity reactions associated with rFIXFc, and no thrombotic events. Adverse events were typical of the pediatric hemophilia B population; no subject discontinued the study due to an adverse event. Median ABRs were low in both age cohorts (Table). Overall, 95% of bleeding episodes were controlled with 1 or 2 infusions.

Conclusions:

Interim data in children with severe hemophilia B participating in B-YOND confirm the long-term safety of rFIXFc and the maintenance of a low ABR with extended-interval prophylactic dosing.

Table. Interim results of the B-YOND study

Pediatric Venous Thrombosis Associated With Staphylococcal Infections: A Single Institutional Experience

Pediatric Venous Thrombosis Associated With Staphylococcal Infections: A Single Institutional Experience

Year: 2015
Grants:
Bleeding Disorders Conference
Clinical Research/Clinical Trials
Author(s):
Divyaswathi Citla Sridhar, Ossama M. Maher, Fernando Corrales-Medina, Hatel Rana Moonat, Jorge Galvez Silva, Trinh Nguyen, Deborah Brown, Nidra I. Rodriguez

Introduction:

Since the emergence of community-acquired methicillin-resistant S. aureus (MRSA), severe manifestations of infection are encountered more frequently. Venous thrombosis (VT) has been previously reported in children with S. aureus infections. This study reviews our institutional experience and outcomes of children with VT and staphylococcal infections.

Methods:

A retrospective analysis of 15 pediatric patients (≤ 18 years) treated for VT and staphylococcal infections at Children’s Memorial Hermann Hospital between January 1, 2010 and December 31, 2014 was performed.

Results:

Fifteen patients were included (10 males, 5 females) with a median age at diagnosis of 8 years (range 2 mo-17yrs). Underlying infections included: osteomyelitis (n=7), soft tissue infection (n=3), aortitis (n=1), meningitis (n=1), septic arthritis (n=1), central line infection (n=1), septicemia (n=1). Primary presentation included: swelling (n=12), pain (n=11), tenderness (n= 8), and color changes (n=3). One patient had prior history of VT. Family history was positive for VT in one patient. Isolated organisms included: MRSA (n=9), MSSA (n=3), polymicrobial (n=2), and Staphylococcus non- aureus (n=1). Eight patients had central venous catheters (CVC) and 5 of them had thrombosis at the CVC site. VT sites identified by Doppler US (DUS) included: upper extremity (n= 5), lower extremity (n= 8), and neck (n=2). All thrombophilia work up was negative. The median D-dimer at diagnosis was 3 ug/ml (range: 0.31- 6.54 ug/ml). Median time elapsed between infection and VT diagnosis was 5.5 days (range: 0-35 days). All patients received anticoagulation using LMWH (1mg/kg/dose) except one who had superficial thrombophlebitis and was managed conservatively. Median time to achieve therapeutic anti- factor Xa level was 2.5 days (range 1- 6 days). Median duration of anticoagulation was 3 months. Three out of 13 patients (23%) had resolution of thrombosis within one week of anticoagulation. Four other patients had thrombus resolution by DUS at 3-6 months. Five patients did not have DUS at 3-6 months. None of the 15 patients required hospital re- admission for bleeding or thrombotic complications.

Discussion:

Staphylococcal infections may increase the risk of VT in children. Nine out of 15 patients (60%) with VT had a documented MRSA infection, which appears to confer an even higher risk for development of VT. Over half of the patients responded favorably to anticoagulation with resolution of VT within 6 months.

Conclusions:

A high index of suspicion for VT is warranted in children with Staphyloccoccal infections (particularly MRSA) to promptly diagnose and treat. This approach may improve outcomes and minimize complications including septic emboli and post-thrombotic syndrome. Prophylactic anticoagulation in presence of MRSA infection could be considered in future studies.

Keywords: Children, staphylococcal infection, venous thrombosis