Long Term Safety and Efficacy of Recombinant Factor IX Fc Fusion Protein (rFIXFc) Prophylaxis in Children with Hemophilia B: Interim Results of the B-Yond Extension Study

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 4976-4976 ◽  
Author(s):  
Jonathan M. Ducore ◽  
Kathelijn Fischer ◽  
Roshni Kulkarni ◽  
Beatrice Nolan ◽  
Carolyn M. Bennett ◽  
...  

Abstract Introduction: The phase 3 Kids B-LONG study (NCT01440946) demonstrated the safety, efficacy, and pharmacokinetics of prophylactic recombinant factor IX Fc fusion protein (rFIXFc) for the prevention and treatment of bleeding episodes in children with severe hemophilia B. The ongoing rFIXFc extension study B-YOND (NCT01425723) is evaluating long-term safety and efficacy of rFIXFc in children and adults with hemophilia B. The safety and efficacy data for pediatric subjects from the second B-YOND interim data cut (11 Sep 2015) are reported here. Methods: The Kids B-LONG study enrolled males aged <12 years with severe hemophilia B (≤2 IU/dL endogenous factor IX [FIX] activity) who had ≥50 exposure days (EDs) of a prior FIX product. Subjects completing Kids B-LONG (median time on study: 49.4 wk) could enroll in 1 of 3 prophylactic treatment groups in B-YOND: weekly prophylaxis (WP; 20-100 IU/kg every 7 d), individualized prophylaxis (IP; 100 IU/kg every 8-16 d), or modified prophylaxis (MP, to optimize prophylaxis with IP or WP). Subjects could change treatment groups at any point in B-YOND. The primary endpoint was development of inhibitors (neutralizing antibody value ≥0.6 BU/mL as measured by the Nijmegen-modified Bethesda assay). Secondary outcomes included annualized bleeding rate (ABR) and rFIXFc exposure days (EDs). Additional outcomes included adverse events (AEs) and evaluation of treatment of bleeding episodes. This analysis reports data for pediatric B-YOND subjects (includes subjects who were <12 y at enrollment into Kids B-LONG) treated with ≥1 dose of rFIXFc. Results: At the time of the second B-YOND interim data cut, 27 subjects had completed Kids B-LONG and enrolled in B-YOND (<6 y cohort, n=13; 6 to <12 y cohort, n=14). Ten subjects had completed (ie, ended participation in the study without premature discontinuation), 16 subjects were ongoing in B-YOND, and 1 subject withdrew due to subject request. From the start of Kids B-LONG to the second B-YOND interim data cut, subjects had a median (range) 2.3 y (0.9-3.0 y) of treatment with rFIXFc, and a median (range) 127.0 (50.0-183.0) cumulative rFIXFc EDs.No inhibitors were observed. AEs were generally typical of the pediatric hemophilia B study population. There were no reports of serious allergic reactions or anaphylaxis associated with rFIXFc, and no vascular thrombotic events; no subjects had AEs related to the study drug. Median (interquartile range [IQR]) overall, spontaneous, and traumatic ABRs were low in both age groups for subjects in the IP and WP treatment groups (Figure; 1 subject in each age cohort was in the MP group [data not shown]). Median (IQR) joint ABRs were 0.0 (0.0-2.2) for subjects < 6 years in the WP treatment group and 0.9 (0.0-2.7) and 1.1 (0.0-2.4) for subjects 6 to <12 years in WP and IP treatment groups, respectively. Regardless of age or treatment group, the majority of bleeding episodes were controlled with 1-2 intravenous injections (<6 y, 97.3%; 6 to <12 y, 97.2%). At the end of Kids B-LONG, 26/27 subjects were dosing once weekly and 1/27 subject was dosing every 5 days. Compared with these dosing intervals, 14.8% of subjects lengthened, 77.8% of subjects did not change, and 7.4% of subjects decreased their prophylactic dosing interval during B-YOND. The median (IQR) dosing interval during B-YOND for pediatric subjects in the IP treatment groups was 10.0 [10.0, 10.7] days. Compared with the end of B-LONG, the median (IQR) total weekly prophylactic dose of rFIXFc was similar at the second B-YOND interim data cut (60.0 [50.0-60.0] vs 60.0 [57.0-70.0]). Conclusion: These data confirm the long-term safety of rFIXFc with maintenance of low ABRs and extended-interval prophylaxis in children with hemophilia B. This research was funded by Biogen and Sobi. Biogen and Sobi reviewed and provided feedback on the abstract. The authors had full editorial control of the abstract and provided their final approval of all content. Disclosures Ducore: Octapharama: Membership on an entity's Board of Directors or advisory committees; Baxalta (Shire): Membership on an entity's Board of Directors or advisory committees; LFB: Membership on an entity's Board of Directors or advisory committees; Bayer: Membership on an entity's Board of Directors or advisory committees; Pfizer: Membership on an entity's Board of Directors or advisory committees; CSL Behring: Membership on an entity's Board of Directors or advisory committees; Biogen: Membership on an entity's Board of Directors or advisory committees. Fischer:Baxter: Consultancy, Research Funding, Speakers Bureau; NovoNordisk: Consultancy, Research Funding, Speakers Bureau; Octapharma: Speakers Bureau; Biogen: Consultancy; Biotest: Consultancy, Speakers Bureau; Baxalta/Baxter: Consultancy, Research Funding, Speakers Bureau; Wyeth: Research Funding; Pfizer: Consultancy, Research Funding, Speakers Bureau; CSL Behring: Consultancy, Speakers Bureau; Bayer: Consultancy, Research Funding, Speakers Bureau; Freeline: Consultancy. Kulkarni:Kedrion: Membership on an entity's Board of Directors or advisory committees; BPL: Membership on an entity's Board of Directors or advisory committees; Biogen: Research Funding, Speakers Bureau; Pfizer: Membership on an entity's Board of Directors or advisory committees; Novo Nordisk: Membership on an entity's Board of Directors or advisory committees, Research Funding; Bayer: Membership on an entity's Board of Directors or advisory committees, Research Funding; Baxter: Membership on an entity's Board of Directors or advisory committees, Research Funding. Nolan:Sobi: Research Funding; Biogen: Research Funding. Perry:Biogen: Consultancy, Honoraria; Novo Nordisk: Consultancy, Membership on an entity's Board of Directors or advisory committees. Yuan:Biogen: Employment, Equity Ownership. Ramirez-Santiago:Biogen: Employment, Equity Ownership. Ferrante:Sobi: Employment. Lethagen:Sobi: Employment.

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 2294-2294
Author(s):  
Amy D Shapiro ◽  
David J Perry ◽  
Ross I Baker ◽  
Elisa Tsao ◽  
Baisong Mei

Abstract Background: The phase 3 B-LONG study demonstrated the safety, efficacy, and pharmacokinetics of recombinant factor IX Fc fusion protein (rFIXFc) for the prevention and treatment of bleeding episodes in subjects with severe hemophilia B. For people with hemophilia, frequent bleeding events occur in target joints, which are a known precursor to hemophilic arthropathy (chronic joint disease). There is currently limited information available on the outcomes of prophylaxis in subjects with target joints who have severe hemophilia B. Aims: To assess the frequency of bleeding events and the dosing of rFIXFc in subjects who had ≥1 target joint at baseline in the B-LONG study. Methods: B-LONG was a Phase 3, multicenter, open-label study that enrolled males aged ≥12 years with severe hemophilia B (≤2 IU/dL endogenous FIX activity) who had received prior treatment with FIX. Subjects in B-LONG were enrolled into 1 of 4 arms: Arm 1, weekly prophylaxis; Arm 2, individualized interval prophylaxis; Arm 3, episodic treatment; or Arm 4, perioperative management. For the current post-hoc analysis, subjects with ≥1 target joint at baseline (per protocol, a target joint was defined as a major joint with ≥3 bleeding episodes in a 3-month period) and who received on-study rFIXFc prophylaxis (Arms 1 and 2 only) were included. On-study per subject target joint ABR (annualized number of bleeding episodes per year in all target joints combined), including overall, spontaneous, and traumatic target joint ABR, were assessed. In subjects with available prestudy and on-study ABR data, prestudy 12-month bleeding rates were compared with on-study overall ABR. Results: Forty-three subjects from the prophylaxis arms had target joints at entry into B-LONG and data collected during the efficacy period of the study (weekly prophylaxis, n = 35; individualized interval prophylaxis, n = 8). Of these, 40 subjects had both prestudy and on-study bleeding information available. Regardless of prestudy treatment regimen (prophylactic or episodic rFIX), on-study median ABRs were low among subjects with target joints at baseline compared with prestudy ABRs (Fig. 1). The on-study overall target joint, spontaneous target joint, and traumatic target joint median (interquartile range, [IQR]) ABRs were low for subjects in the weekly prophylaxis arm (1.03 [0.00, 3.07], 0.00 [0.00, 1.10], and 0.00 [0.00, 1.11], respectively) and for subjects in the individualized interval prophylaxis arm (2.20 [0.00, 3.75], 2.20 [0.00, 3.75], and 0.00 [0.00, 0.00], respectively; Fig. 2). A total of 17 (48.6%) subjects receiving weekly prophylaxis and 3 (37.5%) subjects receiving individualized interval prophylaxis had no target joint bleeding episodes on-study. The average weekly prophylactic rFIXFc dose for subjects with target joints at baseline was (median [IQR]) 46.26 (37.98, 54.55) IU/kg and 69.48 (57.28, 77.45) IU/kg for those receiving weekly prophylaxis and individualized interval prophylaxis, respectively. The median (IQR) average on-study dosing intervals for these groups were 6.98 (6.88, 7.00) days and 10.25 (9.45, 12.72) days, respectively. Among subjects with target joints at baseline who received prestudy rFIX and on-study rFIXFc prophylaxis (n = 6, weekly prophylaxis arm only; no subjects from the individualized interval prophylaxis arm who met these criteria had available data), the on-study median (IQR) average weekly prophylactic dose of 50.61 (39.61, 60.61) IU/kg with rFIXFc was lower than the prestudy median (IQR) average weekly prophylactic dose of 111.28 (95.56, 116.76) IU/kg with rFIX. Additionally, the on-study median (IQR) dosing interval (6.92 [6.79, 6.97]) with rFIXFc prophylaxis was longer than the pre-study median (IQR) dosing interval among these 6 subjects (3.50 [2.33, 3.50] days). Summary/Conclusion: For subjects in the current analysis with severe hemophilia B who entered B-LONG with target joints, rFIXFc prophylaxis was effective for reducing the frequency of bleeding episodes overall and in target joints. Furthermore, in subjects who received prestudy and on-study prophylaxis, rFIXFc was associated with reduced consumption and prolonged dosing intervals compared with conventional prestudy rFIX products. These results suggest that target joints can be effectively managed and controlled with rFIXFc dosed prophylactically every 1 to 2 weeks. Disclosures Shapiro: Baxalta, Novo Nordisk, Biogen, ProMetic Life Sciences, and Kedrion Biopharma: Consultancy; Biogen: Speakers Bureau; Bayer Healthcare, Baxalta, Biogen, CSL Behring, Daiichi Sankyo, Kedrion Biopharma, Octapharma, OPKO, ProMetic Life Sciences, PTC Therapeutics, and Selexys: Research Funding; Baxalta, Novo Nordisk, Biogen,: Membership on an entity's Board of Directors or advisory committees. Perry:Novo Nordisk: Consultancy, Membership on an entity's Board of Directors or advisory committees; Biogen: Consultancy, Honoraria. Baker:Biogen Idec: Membership on an entity's Board of Directors or advisory committees, Research Funding; Boehringer Ingelheim: conference travel support, Membership on an entity's Board of Directors or advisory committees, Research Funding; Bayer: Membership on an entity's Board of Directors or advisory committees, Research Funding; Baxter Healthcare: Membership on an entity's Board of Directors or advisory committees, Other: conference travel support, Research Funding; Pfizer: Membership on an entity's Board of Directors or advisory committees, Research Funding; Daiichi Sankyo: Research Funding; Portola Pharmaceuticals: Research Funding; Astellas: Research Funding; CSL Behring: Research Funding; Amgen: Membership on an entity's Board of Directors or advisory committees, Other: conference travel support; Alexion Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Other: conference travel support; Bristol- Myers Squibb: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novo Nordisk: Other: conference travel support. Tsao:Biogen: Employment, Equity Ownership. Mei:Biogen: Employment, Equity Ownership.


2017 ◽  
Vol 117 (03) ◽  
pp. 508-518 ◽  
Author(s):  
K.John Pasi ◽  
Kathelijn Fischer ◽  
Margaret Ragni ◽  
Beatrice Nolan ◽  
David J. Perry ◽  
...  

SummaryThe safety, efficacy, and prolonged half-life of recombinant factor IX Fc fusion protein (rFIXFc) were demonstrated in the Phase 3 B-LONG (adults/adolescents ≥12 years) and Kids B-LONG (children <12 years) studies of subjects with haemophilia B (≤2 IU/dl). Here, we report interim, long-term safety and efficacy data from B-YOND, the rFIXFc extension study. Eligible subjects who completed B-LONG or Kids B-LONG could enrol in B-YOND. There were four treatment groups: weekly prophylaxis (20–100 IU/kg every 7 days), individualised prophylaxis (100 IU/kg every 8–16 days), modified prophylaxis (further dosing personalisation to optimise prophylaxis), and episodic (ondemand) treatment. Subjects could change treatment groups at any point. Primary endpoint was inhibitor development. One hundred sixteen subjects enrolled in B-YOND. From the start of the parent studies to the B-YOND interim data cut, median duration of rFIXFc treatment was 39.5 months and 21.9 months among adults/adolescents and children, respectively; 68/93 (73.1 %) adults/adolescents and 9/23 (39.1 %) children had ≥100 cumulative rFIXFc exposure days. No inhibitors were observed. Median annualised bleeding rates (ABRs) were low in all prophylaxis regimens: weekly (≥12 years: 2.3; <6 years: 0.0; 6 to <12 years: 2.7), individualised (≥12 years: 2.3; 6 to <12 years: 2.4), and modified (≥12 years: 2.4). One or two infusions were sufficient to control 97 % (adults/adolescents) and 95 % (children) of bleeding episodes. Interim data from B-YOND are consistent with data from B-LONG and Kids B-LONG, and confirm the longterm safety of rFIXFc, absence of inhibitors, and maintenance of low ABRs with prophylactic dosing every 1 to 2 weeks.Supplementary Material to this article is available online at www.thrombosis-online.com.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 2407-2407 ◽  
Author(s):  
Lynn M Malec ◽  
Stacy E. Croteau ◽  
Michael Callaghan ◽  
Davide Matino ◽  
Kenneth Dale Friedman ◽  
...  

Background: Factor IX (FIX) has distinct pharmacokinetic properties compared to factor VIII including significant distribution to the extravascular space. Extravascular distribution and binding to type IV collagen is important in hemostasis but not readily measureable in clinical practice for patients with hemophilia B receiving factor products. We previously reported data regarding use of EHL-FIX products in a cohort of patients who demonstrated issues with spontaneous bleeding and poorly controlled bleeding events; we now report data from an expanded cohort including performance of all EHL-FIX products available in US and Canada. Aims: To characterize the use and performance of EHL-FIX in clinical practice at six hemophilia treatment centers (HTCs). Methods: An electronic survey regarding center specific use of EHL-FIX amongst patients with severe hemophilia B (HB) was sent in summer 2019, including 4 previously surveyed centers and 2 additional centers. Providers were asked if patients utilizing EHL-FIX for prophylaxis had experienced 1) spontaneous/minimally traumatic bleeding events at factor levels >10% or 2) poorly controlled bleeding events requiring more frequent/higher doses of EHL-FIX than anticipated in addition to patterns of EHL-FIX product switching. Results: Surveyed HTCs cared for 90 patients with HB including 67 (74%) who utilized EHL-FIX, including 26 (39%) recombinant factor IX (FIX) albumin fusion protein (rFIX-FP), 37 (55%) recombinant factor IX Fc fusion protein (rFIXFc), and 4 (6%) received glycopegylated recombinant FIX (rFIX-GP). All patients had severe hemophilia B with the exception of one smaller center also contributing data regarding moderate HB patients on prophylaxis. All centers reported having patients with unexpected spontaneous/minimally traumatic bleeding and poorly controlled bleeding which did not seem to be dependent on age (median age 14.5 years, range 1.4-44). This occurred in 18 patients on prophylaxis, including 16 of 26 (62%) patients using rFIX-FP, and 2 of 4 (50%) of patients using rFIX-GP. Conclusions: Although plasma FIX activity levels have driven prophylaxis and bleed management decisions, clinical experience suggests novel properties of EHL-FIX may impact hemostasis. Although achieving seemingly adequate FIX plasma troughs (>10%), limited clinical experience suggests patients with SHB may have a differential response to EHL-FIX, noted in our cohort with FIX-FP and rFIX-GP. Successful bleed prevention or control in SHB may be predicted by the distribution of FIX in circulation and extravascular space, and the presence of FIX in tissues at time of injury. These data demonstrate the importance of real-world monitoring of efficacy of new FIX products and suggest the need for more robust mechanisms to understand the hemostatic performance of products. Disclosures Malec: Bayer: Honoraria; Spark: Honoraria; CSL: Honoraria; Sanofi: Consultancy, Honoraria, Speakers Bureau; Takeda: Honoraria. Croteau:Novo Nordisk: Consultancy, Honoraria, Research Funding; Shire: Consultancy, Honoraria; Bayer: Consultancy, Honoraria; Bayer: Consultancy, Honoraria; Octapharma: Honoraria; Octapharma: Honoraria; Genentech: Consultancy, Honoraria; Pfizer: Research Funding; Spark Therapeutics: Research Funding; Novo Nordisk: Consultancy, Honoraria, Research Funding; Spark Therapeutics: Research Funding; Pfizer: Research Funding; Genentech: Consultancy, Honoraria; CSL Behring: Consultancy, Honoraria; CSL Behring: Consultancy, Honoraria; Shire: Consultancy, Honoraria. Callaghan:Biomarin, Bioverativ, Grifols, Kedrion, Pfizer, Roche/Genentech, Shire, and Spark Therapeutics: Consultancy; Alnylum: Equity Ownership; Bayer: Consultancy, Speakers Bureau; Takeda: Consultancy, Research Funding; Sanofi: Consultancy; Global Blood Therapeutics: Consultancy; Novonordisk: Consultancy, Speakers Bureau; Octapharma: Consultancy; Pfizer: Research Funding; Roche: Research Funding; Shire/Takeda: Speakers Bureau; Roche/Genentech: Speakers Bureau. Matino:Bayer: Honoraria, Research Funding; Sobi: Honoraria, Research Funding; Pfizer: Honoraria, Research Funding; Roche: Research Funding; Bioviiix: Honoraria; Sanofi: Honoraria. Friedman:CSL: Consultancy; Bayer: Consultancy; Genentech: Consultancy; Instrumentation Laboratory: Consultancy; Siemens: Consultancy. Sidonio:Grifols: Membership on an entity's Board of Directors or advisory committees, Research Funding; Genetech: Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda-Shire: Membership on an entity's Board of Directors or advisory committees, Research Funding; Bioverativ: Membership on an entity's Board of Directors or advisory committees, Research Funding; Octapharma: Membership on an entity's Board of Directors or advisory committees, Research Funding; Uniqure: Membership on an entity's Board of Directors or advisory committees; Novo Nordisk: Membership on an entity's Board of Directors or advisory committees; Biomarin: Membership on an entity's Board of Directors or advisory committees; Kedrion: Research Funding.


Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 4978-4978
Author(s):  
Jerzy Windyga ◽  
Toshko Jelev Lissitchkov ◽  
Miranda Chapman ◽  
Srilatha D. Tangada ◽  
Nirjhar Chatterjee

Abstract Pharmacokinetic (PK) parameters are important surrogate indicators for hemostatic efficacy replacement therapy in the treatment of haemophilia patients. Nonacog gamma (Rixubis) is a recombinant factor IX (rFIX) concentrate that is manufactured using two viral inactivation steps (solvent/detergent treatment and nanofiltration) and without any materials of animal origin. Clinical trials of nonacog gamma included a comprehensive evaluation of PK in hemophilia B patients across multiple age groups and a direct comparison to determine equivalence with another licensed, commercially-available factor IX product. The objective of this evaluation was to assess the factor IX activity across clinical development with nonacog gamma. PK parameters for nonacog gamma were evaluated in a non-bleeding state in previously-treated patients with severe (FIX level < 1%) or moderately severe (FIX level 1-2%) hemophilia B in three prospective clinical trials (a pivotal trial in adults,1 a pediatric trial in children aged 2 to 12 years,2 and a third trial in patients undergoing surgical procedures3). Factor IX activity was determined using a one-stage clotting assay. In the pivotal trial, PK equivalence with a comparator recombinant factor IX product (nonacog alfa) was determined by the ratio of AUC0-72 h (area under the plasma concentration versus time curve from 0 to 72 hours post-infusion), per dose with a type I error of 5% for the two-sided 90% confidence interval (equivalence margin: 80% to 125%). Windyga et al. (2014) established bioequivalence of nonacog gamma with a comparator recombinant factor IX in the pivotal trial (N=27), as the 90% CI for the ratio of the AUC0-72 h per dose ranged from 103% to 109%.1 A plot of mean factor IX activity levels versus time after start of infusion on a linear scale and log scale (figure 1a and 1b) depicts the equivalence throughout the 72-hour follow-up period. A similar pattern can be observed in the linear and log regression for mean factor IX activity in pediatric patients (N=23). These results are further supported by consistent PK parameters determined prior to surgical intervention in the surgery trial (N=12).3 Two important PK parameters determined in each study were as follows: mean [STD] T ½ 26.70h (9.55), incremental recovery (IR) 0.87 (0.22) for nonacog gamma and 27.87h (9.22), IR 0.76 (0.20) for the comparator rFIX in the pivotal trial, 25.31h (3.130), IR 0.67 (0.16) in the pediatric trial, and 23.60h (3.60), IR 1.06 (0.35) in the surgery trial. Conclusion Factor IX activity of nonacog gamma throughout its clinical development support previous finding of its equivalence with another licensed recombinant factor IX concentrate in patients with severe to moderately severe hemophilia B. References 1. Windyga J, Lissitchkov T, Stasyshyn O, et al. Pharmacokinetics, efficacy and safety of BAX326, a novel recombinant factor IX: a prospective, controlled, multicentre phase I/III study in previously treated patients with severe (FIX level <1%) or moderately severe (FIX level ≤2%) haemophilia B. Haemophilia. 2014 Jan;20(1):15-24. 2. Urasinski T, Stasyshyn O, Andreeva T, et al. Recombinant factor IX (BAX326) in previously treated paediatric patients with haemophilia B: a prospective clinical trial. Haemophilia. 2015 Mar;21(2):196-203. 3. Windyga J, Lissitchkov T, Stasyshyn O, et al. Efficacy and safety of a recombinant factor IX (Bax326) in previously treated patients with severe or moderately severe haemophilia B undergoing surgical or other invasive procedures: a prospective, open-label, uncontrolled, multicentre, phase III study. Haemophilia. 2014 Sep;20(5):651-8. Disclosures Windyga: Baxalta, now part of Shire: Consultancy, Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Investigator Clinical Studies, Patents & Royalties, Research Funding, Speakers Bureau; Nordisk: Consultancy, Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding, Speakers Bureau; Sanofi: Consultancy, Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding, Speakers Bureau; Biogen: Consultancy, Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding, Speakers Bureau; CSL Behring: Consultancy, Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding, Speakers Bureau; Octapharma: Consultancy, Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding, Speakers Bureau; Alexion: Other: Speaker's honorarium; Aspen: Consultancy, Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding, Speakers Bureau. Chapman:Baxalta (Now part of Shire): Employment, Equity Ownership. Tangada:Baxalta US Inc., now part of Shire: Employment, Equity Ownership. Chatterjee:Baxalta (Now part of Shire): Employment, Equity Ownership.


Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 2585-2585
Author(s):  
Jerzy Windyga ◽  
Toshko Jelev Lissitchkov ◽  
Vasily Mamonov ◽  
Miranda Chapman ◽  
Srilatha D. Tangada ◽  
...  

Abstract Management of hemostasis with factor IX replacement during surgical procedures on patients with hemophilia B is vital to patient safety. A recombinant factor IX (rFIX, nonacog gamma, RIXUBIS, BAX 326) presents a treatment alternative for hemophilia B; nonacog gamma is manufactured with no materials of human or animal origin, and includes as two-step virus inactivation (solvent/detergent treatment and nanofiltration). This multi-national clinical trial was conducted to investigate the efficacy and safety of nonacog gamma for perioperative use in previously-treated patients with severe (FIX level < 1%) or moderately severe (FIX level 1-2%) hemophilia B. Interim results of 14 (11 major) surgeries showed that nonacog gamma is safe and effective in maintaining hemostasis in the surgical setting;1 the results of all 38 surgeries are presented here. Previously-treated hemophilia B immunocompetent patients aged 12 to 65 years with no evidence of a history of FIX inhibitors were eligible for participation if they were either: 1) participating in another trial with nonacog gamma and required an emergency or elective major or minor surgical, dental, or other invasive procedure; or 2) if not participating in any other nonacog gamma clinical study, they required elective major surgery and had been treated previously with plasma-derived and/or recombinant FIX concentrate(s) for a minimum of 150 exposure days. Pre-operative FIX levels were targeted at 80%-100% of normal for major, and 30%-60% of normal for minor surgeries, through an individualized nonacog gamma dosing approach. Hemostatic efficacy was evaluated intra- and post-operatively by determination of actual versus predicted blood loss and a semi-quantitative 4-point hemostatic efficacy rating scale (excellent, good, fair, none); safety was assessed in terms of the occurrence of adverse events. Thirty patients participated in this study, 10 of whom underwent multiple surgeries and were re-enrolled for each surgery. Of a total of 38 surgeries performed, 21 were major (14 orthopedic) and 17 were minor. Hemostatic efficacy for 37/38 surgeries (including 20/21 major surgeries) had a rating of 'excellent' and one was 'good' (a knee joint replacement). At drain removal (n=14), the ratings for all major surgeries were either 'excellent' (10/14) or 'good' (4/14). On postoperative day 3, 6 of 7 major surgeries where no drain was employed had a rating of 'excellent', and one had a rating of 'good'. At discharge from hospital, 12/21 were 'excellent', 7/21 were 'good' and 2 were 'fair' (both had ratings of 'excellent' intraoperatively and at drain removal). For 16/21 major surgeries, the actual blood loss was below (n=8) or equal to (n=8) the average predicted blood loss and the mean post-operative blood loss was 552.4 mL (range: 11-1100 mL) in subjects who had a drain placed. For 12/17 minor surgeries, actual intraoperative blood loss was below the average predicted blood loss, for 4/17 minor surgeries, the actual intraoperative blood loss matched the average predicted blood loss, and for 1 minor surgery (intra-articular infiltration) actual blood loss was between the average predicted and maximum predicted blood loss. Nonacog gamma was safe and well tolerated. One possibly related AE (hemorrhagic anemia) was reported. This event was resolved at the completion of the study. No thrombogenic events or severe allergic reactions, nor induction of inhibitory antibodies to FIX or total binding antibodies to FIX were observed. Conclusion: Nonacog gamma provides a safe and effective treatment alternative for perioperative management of hemostasis in hemophilia B patients in a variety of surgical settings. References 1 Windyga J, Lissitchkov T, Stasyshyn O, et al. Efficacy and safety of a recombinant factor IX (Bax326) in previously treated patients with severe or moderately severe haemophilia B undergoing surgical or other invasive procedures: a prospective, open-label, uncontrolled, multicentre, phase III study. Haemophilia. 2014 Sep;20(5):651-8. Disclosures Windyga: CSL Behring: Consultancy, Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding, Speakers Bureau; Biogen: Consultancy, Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding, Speakers Bureau; Nordisk: Consultancy, Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding, Speakers Bureau; Aspen: Consultancy, Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding, Speakers Bureau; Sanofi: Consultancy, Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding, Speakers Bureau; Baxalta, now part of Shire: Consultancy, Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Investigator Clinical Studies, Patents & Royalties, Research Funding, Speakers Bureau; Octapharma: Consultancy, Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding, Speakers Bureau; Alexion: Other: Speaker's honorarium. Mamonov:Baxalta (Now part of Shire): Research Funding. Chapman:Baxalta (Now part of Shire): Employment, Equity Ownership. Tangada:Baxalta US Inc., now part of Shire: Employment, Equity Ownership. Abbuehl:Shire, formerly Baxalta and Baxter: Employment, Equity Ownership.


Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 26-26
Author(s):  
Frank W.G. Leebeek ◽  
Karina Meijer ◽  
Michiel Coppens ◽  
Peter Kampmann ◽  
Robert Klamroth ◽  
...  

Background: Gene therapy aims to provide long-term therapeutic benefit from a single administration. AMT-060 is an adeno-associated virus serotype 5 (AAV5) vector with a codon-optimized wildtype human factor IX (FIX) gene and liver-specific promoter. AMT-060 is being evaluated in an ongoing study of 10 participants with severe/moderate-severe hemophilia B (Phase 1/2 study, NCT02396342) over 5 years. Aim: To describe efficacy and safety outcomes from an analysis at up to 5-years post-AMT-060. Methods: Adult males with FIX activity ≤2% and a severe bleeding phenotype received a single intravenous infusion of AMT-060 (5x1012 gc/kg, Cohort 1, n=5) or (2×1013 gc/kg, Cohort 2, n=5). Assessments included FIX activity, FIX replacement use, annualized bleeding rate (ABR), treatment-related adverse events (TRAE), immunological and inflammatory biomarkers up to 5 years (Cohort 1) and 4.5 years (Cohort 2). Results: As of November 2019, for Cohort 1 the mean FIX activity (at 4.0 years) was 5.1% as compared to 4.4% in the first year, 6.8% in the second year, 7.3% in the third year and 7.0% in the fourth year. Mean FIX activity for Cohort 2 was 7.5% as compared to 7.1% in the first year, 8.4% in the second year 7.9% in the third year, and 7.4% in the fourth year. Eight of 9 participants using prophylaxis at baseline were able to discontinue use. During the last 12, and 6 months of observation respectively, the mean annualized bleed rate (ABR) was 3.3. for Cohort 1 and 0.0 for Cohort 2. These represent, respectively, a reduction in mean ABR to the year prior to treatment of 77% and 100% for Cohort 1 and Cohort 2. During this same period the consumption of FIX replacement therapy declined 90% and 100% relative to pre-treatment, respectively for Cohort 1 and Cohort 2. No participants developed FIX inhibitors or signs of sustained AAV5 capsid-specific T-cell activation. As previously reported, TRAE were mainly reported in the first 3.5 months after treatment, including three participants who experienced transient mild elevations in alanine aminotransferase. One additional TRAE (joint swelling post-exercise) was observed during the last 12 months of observation post-treatment. Updated data, up to 5-years of observation, will be presented for the first time. Conclusions: Long-term stable endogenous FIX activity and reductions in ABR and FIX replacement use were sustained over multiple years following a single treatment with AMT-060. There were no additional safety concerns with longer term follow-up. This data supports the ongoing Phase 3 study of the enhanced construct etranacogene dezaparvovec (AMT-061), which encodes the highly active Padua FIX variant. Disclosures Meijer: Bayer: Research Funding; Sanquin: Research Funding; Pfizer: Research Funding; Bayer: Speakers Bureau; Sanquin: Speakers Bureau; Boehringer Ingelheim: Speakers Bureau; BMS: Speakers Bureau; Aspen: Speakers Bureau; Uniqure: Consultancy. Kampmann:Uniqure: Speakers Bureau; Shire Pharmaceuticals: Speakers Bureau. Klamroth:CSL Behring: Research Funding, Speakers Bureau; Novo Nordisk: Consultancy, Research Funding, Speakers Bureau; Octapharma: Consultancy, Research Funding, Speakers Bureau; Pfizer: Consultancy, Research Funding, Speakers Bureau; Roche: Consultancy, Speakers Bureau; Takeda/Shire: Consultancy, Research Funding, Speakers Bureau; Sobi: Consultancy, Speakers Bureau; Biotest: Speakers Bureau; Grifols: Speakers Bureau; Biomarin: Consultancy, Research Funding, Speakers Bureau; Bayer: Consultancy, Research Funding, Speakers Bureau. Castaman:Novo Nordisk: Honoraria, Speakers Bureau; Roche: Consultancy, Honoraria, Speakers Bureau; Pfizer: Honoraria, Research Funding; Ablynx: Honoraria; Alexion: Honoraria; Bayer: Honoraria; CSL Behring: Honoraria, Research Funding; Kedrion: Speakers Bureau; Sobi: Honoraria, Research Funding, Speakers Bureau; Uniqure: Honoraria, Membership on an entity's Board of Directors or advisory committees; Werfen: Speakers Bureau; Baxalta/Shire: Honoraria. Bönig:Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees; Genzyme: Consultancy, Membership on an entity's Board of Directors or advisory committees; Healthineers: Current equity holder in publicly-traded company; Sandor-Hexal: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Polyphor: Research Funding; Miltenyi: Honoraria, Research Funding; Erydel: Research Funding; Chugai: Honoraria, Research Funding; Bayer: Research Funding; Terumo BCT: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Kiadis: Honoraria; Uniqure: Research Funding; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Stage: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Fresenius: Honoraria; medac: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties. Sawyer:uniQure: Current Employment. Miesbach:UniQure: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Pfizer: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; BioMarin Pharmaceutical Inc: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Bayer: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. OffLabel Disclosure: AMT-060 = AAV5 vector gene therapy in subjects with moderate to severe hemophilia B


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 3512-3512
Author(s):  
Rachael F. Grace ◽  
D. Mark Layton ◽  
Frédéric Galactéros ◽  
Wilma Barcellini ◽  
Eduard J. van Beers ◽  
...  

Background: Pyruvate kinase (PK) deficiency is a congenital hemolytic anemia caused by mutations in the PKLR gene, leading to a deficiency of the glycolytic enzyme red cell PK (PK-R). Current treatments for PK deficiency are supportive only. Mitapivat (AG-348) is an oral, small-molecule, allosteric PK-R activator in clinical trials for PK deficiency. We previously described results from DRIVE PK, a phase 2, randomized, open-label, dose-ranging study in adults with PK deficiency (N=52) treated with mitapivat for a median of 6 months. Aim: To report long-term safety and efficacy of mitapivat in patients who continue treatment in the ongoing Extension period of the DRIVE PK study (ClinicalTrials.gov NCT02476916). Methods: Patients were eligible to participate if ≥18 years of age with a confirmed diagnosis of PK deficiency (enzyme and molecular testing); baseline hemoglobin (Hb) levels ≤12.0 g/dL (males) or ≤11.0 g/dL (females); and if they had not received more than 3 units of red blood cells in the prior 12 months, with no transfusions in the prior 4 months. Patients were initially randomized 1:1 to receive mitapivat 50 mg twice daily (BID) or 300 mg BID for a 6-month Core period. Dose adjustment was allowed during the Core period based on safety and efficacy. Patients experiencing clinical benefit without concerning safety issues related to mitapivat (investigator discretion) could opt to enter the Extension period, with follow-up visits every 3 months. Safety (adverse events [AEs]) and efficacy (hematologic parameters including Hb) were assessed. Protocol amendments during the Extension period required that (1) patients who did not have an increase from baseline Hb of ≥1.0 g/dL for ≥3 of the prior 4 measurements withdraw from the study, and (2) patients treated with mitapivat doses &gt;25 mg BID undergo a dose taper and continue on the dose that maintained their Hb level no lower than 1.0 g/dL below their pre-taper Hb level. Results: Fifty-two patients enrolled in this study and were treated in the 24-week Core period; 43 (83%) patients completed the Core period and 36 (69%) entered the Extension period. Eighteen patients discontinued from the Extension period: investigator decision (n=8), AEs (n=1), consent withdrawal (n=1), noncompliance (n=1), or other (n=7). Thus, 18 patients, all of whom received ≥29 months of treatment with mitapivat (median 35.6, range 28.7-41.9) have continued treatment. Ten of these 18 patients were male, 11 had a prior splenectomy, and 5 had a history of iron chelation. Median age was 33.5 (range 19-61) years; mean baseline Hb was 9.7 (range 7.9-12.0) g/dL. All patients had ≥1 missense PKLR mutation. The doses (post-taper) at which treatment was continued were (BID): ≤25 mg (n=12), 50 mg (n=5), and 200 mg (n=1). Improvements in Hb levels and markers of hemolysis (reticulocytes, indirect bilirubin, haptoglobin) were sustained (Figure). Among the 18 patients, headache was the most commonly reported AE during both the Extension (n=7, 38.9%) and Core (n=10, 55.6%) periods. Reports of insomnia and fatigue during the Extension period (n=5, 27.8% each) were the same as or similar to those during the Core period. There were fewer reports of nausea (2 vs 6) and hot flush (0 vs 5) in the Extension period. Nasopharyngitis was reported in 5 patients in the Extension period vs 1 patient in the Core period. These data are consistent with the AE profile for the 52 patients treated overall in the Core period, in that headache (44%), insomnia (40%), and nausea (38%) were the most commonly reported AEs and were transient (generally resolved within 7 days without intervention). Conclusion: Chronic daily dosing with mitapivat for a median of 3 years was well tolerated, with no new safety signals reported. Increased Hb levels and improvements in hemolysis markers were sustained at the optimized individual doses. These long-term data support the potential of mitapivat as the first disease-altering therapy for PK deficiency. Two phase 3 trials are underway to further study the effect of mitapivat in patients with PK deficiency. Disclosures Grace: Novartis: Research Funding; Agios Pharmaceuticals, Inc: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Layton:Novartis: Membership on an entity's Board of Directors or advisory committees; Cerus Corporation: Membership on an entity's Board of Directors or advisory committees; Agios: Membership on an entity's Board of Directors or advisory committees. Galactéros:Addmedica: Membership on an entity's Board of Directors or advisory committees. Barcellini:Novartis: Research Funding, Speakers Bureau; Alexion: Consultancy, Research Funding, Speakers Bureau; Apellis: Consultancy; Incyte: Consultancy, Other: Advisory board; Agios: Consultancy, Other: Advisory board; Bioverativ: Consultancy, Other: Advisory board. van Beers:Agios Pharmaceuticals, Inc.: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Consultancy, Research Funding; Pfizer: Research Funding; RR Mechatronics: Research Funding. Ravindranath:Agios Pharmaceuticals, Inc.: Other: I am site PI on several Agios-sponsored studies, Research Funding. Kuo:Agios: Consultancy; Alexion: Consultancy, Honoraria; Apellis: Consultancy; Bioverativ: Other: Data Safety Monitoring Board; Bluebird Bio: Consultancy; Celgene: Consultancy; Novartis: Consultancy, Honoraria; Pfizer: Consultancy. Sheth:Apopharma: Other: Clinical trial DSMB; CRSPR/Vertex: Other: Clinical Trial Steering committee; Celgene: Consultancy. Kwiatkowski:bluebird bio, Inc.: Consultancy, Research Funding; Apopharma: Research Funding; Novartis: Research Funding; Terumo: Research Funding; Celgene: Consultancy; Imara: Consultancy; Agios: Consultancy. Hua:Agios Pharmaceuticals, Inc.: Employment, Equity Ownership. Hawkins:Bristol Myers Squibb: Equity Ownership; Infinity Pharma: Equity Ownership; Agios: Employment, Equity Ownership; Jazz Pharmaceuticals: Equity Ownership. Mix:Agios: Employment, Equity Ownership. Glader:Agios Pharmaceuticals, Inc: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding.


Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 59-59 ◽  
Author(s):  
Claire N. Harrison ◽  
Alessandro M. Vannucchi ◽  
Jean-Jacques Kiladjian ◽  
Haifa Kathrin Al-Ali ◽  
Heinz Gisslinger ◽  
...  

Abstract BACKGROUND: Ruxolitinib (RUX) is a potent JAK1/JAK2 inhibitor that has demonstrated rapid and durable improvements in splenomegaly and symptoms as well as improved survival in the two phase 3 COMFORT studies in patients (pts) with myelofibrosis (MF). In COMFORT-II, significantly more pts achieved the primary endpoint (a ≥ 35% decrease in spleen volume from baseline at wk 48) with RUX compared with best available therapy (BAT) (28% vs 0%; P ˂ .0001). The 3-year follow-up confirmed that spleen volume reductions were sustained and RUX treatment remained tolerable with long-term use. Here, we report final study results on longer-term safety and efficacy after 5 years of RUX treatment in COMFORT-II. METHODS: COMFORT-II is a randomized (2:1), open-label phase 3 study of RUX vs BAT in pts with intermediate-2- or high-risk primary MF, post-PV MF, or post-ET MF. Pts initially received RUX 15 or 20 mg bid based on their platelet counts at baseline (100-200 and > 200 x 109/L, respectively), and doses were individually titrated to maximize safety and efficacy. Pts were allowed to cross over from the BAT arm to receive RUX upon protocol-defined progression (primarily progressive splenomegaly, a ≥ 25% increase in spleen volume from on-study nadir). All pts randomized to BAT had crossed over or discontinued by Nov 2011. The date of final database lock for the study is 20 Apr 2015. RESULTS: Pts were randomized to RUX (n = 146) or BAT (n = 73). Baseline characteristics were well balanced between arms and have been described previously (Harrison, N Engl J Med, 2012); disease and hematologic characteristics were representative of a population of pts with advanced primary or secondary MF. At study completion (median follow-up, 4.3 years), 39 pts (26.7%) in the RUX arm and 11 of the 45 pts (24.4%) who crossed over from BAT completed 5 years of on-study treatment. Primary reasons for premature discontinuation before 5 years were adverse events (AEs; 24.0%) and disease progression (21.9%) in the RUX arm and withdrawal of consent and other in the BAT arm (12.3% each). Overall 78 pts (53.4%) in the RUX arm achieved a ≥ 35% reduction in spleen volume from baseline at any time during treatment; the median duration of maintenance of spleen volume reduction was 3.2 years. The K-M estimated probability of maintaining this reduction was 0.51 (95% CI, 0.38-0.62) at 3 years and 0.48 (95% CI, 0.35-0.60) at 5 years. Approximately one-third of evaluable JAK2 V617F-positive pts had a ˃ 20% reduction in allele burden at 3.2 years (38.3%) and 3.7 years (31.0%). With RUX treatment, 23 pts (15.8%) had improved fibrosis (including 4 who improved to grade 0 from baseline fibrosis grades of 1 [n = 1], 2 [n = 2], and 3 [n = 1]), 47 pts (32.2%) had stable fibrosis, and 27 (18.5%) had a worsening at their last assessment. There was no relevant increase in the incidence of AEs with longer exposure (median: RUX arm, 2.6 years; BAT arm, 0.87 years; RUX after crossover, 1.2 years) compared with previous reports. The most commonly reported AEs in pts who received RUX any time (randomized treatment, extension phase or after cross over from BAT) were thrombocytopenia (52.4%), anemia (49.2%), diarrhea (35.6%), and peripheral edema (33.0%); grade 3/4 AEs included anemia (22.5%), thrombocytopenia (15.2%), pneumonia (5.8%), general physical health deterioration (4.2%), and dyspnea (4.2%). 8 pts (5.5%) and 5 pts (6.8%) developed leukemia in the RUX and BAT arms, respectively. There were no new or unexpected AEs. Overall, 59 (40.4%) and 35 (47.9%) deaths were reported in the RUX and BAT arms, respectively. Median OS was not reached in the RUX arm and was 4.1 years in the BAT arm. There was a 33% reduction in risk of death with RUX compared with BAT (HR, 0.67; 95% CI, 0.44-1.02; P = .06). The K-M estimated probability of survival at 5 years was 56% with RUX and 44% with BAT. As expected, the confounding effect on OS of crossover from BAT to RUX became apparent in this extended follow up compared with previous analyses; an analysis of OS correcting for crossover will be presented. SUMMARY/CONCLUSIONS: The immediate benefits of RUX treatment, such as improvements in spleen size, were maintained with long-term therapy. The previously reported OS benefit was maintained, although results are confounded by extensive crossover from the BAT arm following the primary analysis at wk 48, which becomes more apparent with longer follow-up. Long term safety and tolerability was consistent with previous findings. Disclosures Harrison: Novartis: Honoraria, Research Funding, Speakers Bureau; Gilead: Honoraria; Sanofi: Honoraria, Speakers Bureau; CTI Biopharma: Consultancy, Honoraria, Speakers Bureau; Shire: Speakers Bureau. Vannucchi:Shire: Speakers Bureau; Novartis: Other: Research Funding paid to institution (University of Florence), Research Funding; Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Baxalta: Membership on an entity's Board of Directors or advisory committees. Kiladjian:Incyte Corporation: Consultancy; Novartis: Other: Travel grant; Research Funding paid to institution (Hôpital Saint-Louis et Université Paris Diderot); Novartis: Consultancy. Al-Ali:Celgene: Honoraria, Research Funding; Novartis: Consultancy, Honoraria, Research Funding. Gisslinger:AOP ORPHAN: Consultancy, Honoraria, Research Funding, Speakers Bureau; Novartis: Honoraria, Research Funding, Speakers Bureau; Janssen Cilag: Honoraria, Speakers Bureau; Geron: Consultancy; Celgene: Consultancy, Honoraria, Research Funding, Speakers Bureau; Sanofi Aventis: Consultancy. Knoops:Novartis: Consultancy. Cervantes:Novartis: Consultancy, Speakers Bureau; CTI-Baxter: Consultancy, Speakers Bureau; Sanofi-Aventis: Consultancy. Jones:Incyte Corporation: Employment. Sun:Incyte Corporation: Employment. Descamps:Novartis Pharma S.A.S: Employment. Stalbovskaya:Novartis Pharma AG: Employment, Equity Ownership. Gopalakrishna:Novartis Pharma AG: Employment. Barbui:Novartis: Speakers Bureau.


Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 1087-1087 ◽  
Author(s):  
K John Pasi ◽  
David J Perry ◽  
Johnny Mahlangu ◽  
Barbara A Konkle ◽  
Savita Rangarajan ◽  
...  

Abstract Background: Prophylactic replacement of coagulation factor VIII (FVIII) is the standard of care for patients with hemophilia A; however, prophylactic treatment with conventional FVIII products usually requires frequent intravenous infusions (3-4 times/week). Recombinant FVIII Fc fusion protein (rFVIIIFc), which is produced in a human cell line, binds the neonatal Fc receptor and utilizes the natural IgG recycling pathway to prolong the half-life of FVIII. The safety, efficacy and prolonged half-life of rFVIIIFc in adults and adolescents with severe hemophilia A were demonstrated in the phase 3 A-LONG study (NCT01027377, completed) and ASPIRE extension study (NCT01454739, ongoing). Here, we report cumulative long-term data on the safety and efficacy of rFVIIIFc in participants in these studies. Methods: This longitudinal analysis includes cumulative data from A-LONG and ASPIRE (as of the interim data cut, 6 January 2014) for subjects treated with ≥1 dose of rFVIIIFc (n=164). A-LONG evaluated 2 prophylaxis regimens-individualized (IP): 25 IU/kg on day 1 and 50 IU/kg on day 4 to start, then 25-65 IU/kg every 3-5 days, to target a 1-3 IU/dL FVIII trough level, and weekly (WP): 65 IU/kg dosed once weekly-as well as episodic (on-demand) treatment. Subjects completing A-LONG and meeting enrollment criteria for ASPIRE could participate in the IP, WP, or episodic treatment groups, or, if optimal dosing could not be achieved with IP or WP, in an additional modified prophylaxis (MP) treatment group. Subjects could change treatment groups at any point during ASPIRE. For efficacy analyses, data were summarized according to the treatment group in which each subject participated, for the time period they were in that treatment group; thus, subjects may be included in the analysis of more than one treatment group. Outcomes evaluated included: incidence of inhibitors (neutralizing antibody value ≥0.6 BU/mL as measured by the Nijmegen-modified Bethesda assay at a central laboratory, confirmed upon retesting within 2 to 4 weeks), adverse events (AEs), annualized bleeding rate (ABR), treatment of acute bleeds, and prophylactic dose and dosing interval. Results: Of the 164 subjects dosed with rFVIIIFc during A-LONG, 153 completed the study and 150 enrolled in ASPIRE. At the time of the interim data cut, 140 subjects were ongoing in ASPIRE. Cumulatively, subjects had a median (IQR) of 25.5 (24.6, 26.7) months of rFVIIIFc treatment, and a median (IQR) of 183.0 (120.5, 232.5) rFVIIIFc exposure days (EDs). No inhibitors were reported. The estimated inhibitor incidence rate (95% CI) was 0.0% (0.0, 2.2) overall (N=164), and 0.0% (0.0, 2.7) in subjects with ≥100 rFVIIIFc EDs (n=136). The type and incidence of AEs observed were consistent with those expected for the general hemophilia population. 84.8% of subjects reported ≥1 AE on study, with the majority assessed by the investigator as mild and unrelated to rFVIIIFc treatment. 17.7% of subjects experienced at least 1 SAE; none were assessed by the investigator as related to rFVIIIFc. There were no reports of anaphylaxis or serious hypersensitivity events, and no serious vascular thrombotic events. Median ABRs for subjects on IP and WP (MP was not an option during A-LONG) were generally lower with rFVIIIFc treatment compared with prestudy FVIII (Figure). In the IP treatment group, the year 1 and year 2 median spontaneous ABRs were 0.0. Overall, 89.1% of bleeding episodes were controlled with 1 infusion; 97.3% with 1 or 2 infusions. Among subjects treated with FVIII prophylaxis prior to entering A-LONG (n=79), 86% were dosed at least 3 times/week. With rFVIIIFc, 96% of these subjects extended their dosing interval compared with their prestudy product, while the median (IQR) total weekly prophylactic dose was comparable (prestudy FVIII: 78.0 [60.0, 102.0] IU/kg; on-study rFVIIIFc: 75.0 [70.0, 113.2] IU/kg). Conclusions: Longitudinal data from patients with severe hemophilia A treated with rFVIIIFc in A-LONG and ASPIRE demonstrate long-term safety, with no inhibitors observed in any subjects, and efficacy in the prevention and treatment of bleeding. Low median ABRs were maintained with extended prophylactic dosing intervals, without an increase in median prophylactic factor consumption. Figure 1. Figure 1. Disclosures Pasi: Biogen, Octapharma, Genzyme, and Pfizer: Consultancy, Honoraria; Octapharma: Research Funding. Perry:Novo Nordisk: Consultancy, Membership on an entity's Board of Directors or advisory committees; Biogen: Consultancy, Honoraria. Mahlangu:Roche: Research Funding; Biotest: Speakers Bureau; Bayer, CSL, Novo Nordisk, and Biogen: Research Funding, Speakers Bureau; Amgen: Speakers Bureau. Konkle:Baxalta: Consultancy, Research Funding; Biogen: Consultancy, Research Funding; CSL Behring: Consultancy, Other: IDMC chair; Pfizer: Other: IDMC member; Octapharma: Research Funding; Novo Nordisk: Consultancy. Rangarajan:Grifols, Pfizer, and Baxter: Research Funding; Grifols: Honoraria; Sobi: Membership on an entity's Board of Directors or advisory committees; LFB: Other: Conference support. Brown:Biogen, Novo Nordisk, Baxter, and Pfizer: Other: Sponsorship to meeting. Hanabusa:Novo Nordisk, Baxalta, Bayer, Pfizer, Biogen, and KaketsuKen: Honoraria; Novo Nordisk, Baxalta, KaketsuKen, and Biogen: Membership on an entity's Board of Directors or advisory committees. Jackson:Biogen: Honoraria, Speakers Bureau; Baxalta: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Bayer: Membership on an entity's Board of Directors or advisory committees; Novo Nordisk: Membership on an entity's Board of Directors or advisory committees. Cristiano:Biogen: Employment, Equity Ownership. Dong:Biogen: Employment, Equity Ownership. Tsao:Biogen: Employment, Equity Ownership. Pierce:Biogen: Equity Ownership, Other: Former employee. Allen:Biogen: Employment, Equity Ownership.


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 3124-3124 ◽  
Author(s):  
Paul E. Monahan ◽  
Junjiang Sun ◽  
Tong Gui ◽  
David G Wichlan ◽  
Scott W McPhee ◽  
...  

Abstract Abstract 3124 Persistent factor IX expression and phenotypic improvement have been achieved in a human clinical trial for hemophilia B using liver-directed adeno-associated virus (AAV) gene therapy vectors. An ongoing clinical trial uses a vector incorporating self-complementing AAV (scAAV) genome form, factor IX codon optimization (FIXopt) and AAV serotype 8 capsid. As was seen in a previous single-strand AAV serotype 2 trial, dose escalation has been associated with apparent immune-mediated transient inflammation of vector-transduced liver, although in contrast to the previous trial persistent FIX expression has been maintained for the first time. Taken together, these important trials define a consistent threshold load of AAV capsid that has stimulated capsid-specific cytotoxic lymphocyte recognition and potential transaminitis. To advance the successes achieved in these trials while providing a clear margin of safety so that this immunogenic threshold need not be approached, we have pursued steps to limit further the AAV capsid load. Single amino acid substitutions at arginine 338 in the FIX catalytic domain generate FIX variants with increased specific activity. We separately substituted either R338A, R338Q, or R338L (FIX Padua) into a codon optimized human factor IX cDNA and evaluated F.IX expression in tissue culture following plasmid DNA transfection of HEK 293t cells. Each R338 substitution improved FIX specific activity, up to 10 times increased over wild type using the R338LFIXopt cDNA. We next generated scAAV8 vectors incorporating a liver-specific transthyretin (TTR) promoter to express optimized codon F.IX cDNA with or without the R338L substitution. FIX−/− mice receiving portal vein injection of 1 × 1010 vg/animal (4 ×1011 vg/kg) expressed 86.5% of normal FIX activity at 2 months post-transduction from the WTopt vector and 330% normal from the R338LFIXopt. Incorporation of R338Lopt variant resulted in at least 6 to 10 fold increase in FIX specific activity over a follow-up of > 40 weeks. At ten months following FIX gene delivery, mice underwent a tail transection bleeding challenge. FIX vector mice demonstrated therapeutic protection from this major bleeding challenge and furthermore all survived with no late rebleeding (a hallmark of hemophilic phenotype). Greater than 100% normal human FIX activity was maintained for >40 weeks following treatment with the R338LFIX vector (v. 26.3% at euthanasia in WTopt vector group). The prolonged follow-up permitted extended safety evaluation. Factor IX inhibitor antibodies were not detected in any mice throughout the follow-up; FIX-binding IgG1 and IgG2 were negative also. Thrombin/antithrombin III complexes (TAT) examined at 12 weeks and at >30 weeks of age in R338LFIXopt vector mice did not differ from levels in WTFIXopt vector-treated or age-matched C57Bl/6 hemostatically normal mice. Necropsy at 40–44 weeks after vector (1 year of age) showed only age-related changes with no microvascular or macrovascular thrombosis on H&E staining or specific immunostaining for fibrin/fibrinogen deposition; specific staining for fibrosis within myocardium or other sites was negative. We next synthesized a R338LFIXopt expression cassette containing the LP1 promoter/enhancer/intron sequence being used in the ongoing clinical trial and demonstrated equivalent FIX activity from either promoter construct. We then established that the R338LFIXopt vector gives a predictable dose-response across a range of doses as low as 1x 1010 vg/kg I.V. and as high as 4 × 1012 vg/kg I.V. Hemarthrosis is the most common bleeding complication in hemophilia and leads to chronic joint destruction. Bleeding was induced in the joint of FIX−/− mice that had been transduced 4 weeks earlier with the R338LFIX vector. Joints were collected at 2 weeks after induced bleed and the bleeding-induced joint damage was graded using an established histologic score. I.V. R338LFIXopt vector pretreatment resulted in protection against joint degeneration in a dose-dependent fashion in this most relevant clinical scenario. These preclinical studies demonstrate a safety :efficacy profile to advance hemophilia gene therapy using the scAAV8.R338LFIXopt vector. Disclosures: Monahan: Baxter: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Bayer: Honoraria, Membership on an entity's Board of Directors or advisory committees; Pfizer: Membership on an entity's Board of Directors or advisory committees, Research Funding; Asklepios BioPharmaceutical: Patents & Royalties, Research Funding; CSL Behring: Honoraria; NovoNordisk: Honoraria, Membership on an entity's Board of Directors or advisory committees; PharmaIN: Research Funding; Prolor-Biotech: Research Funding. McPhee:Asklepios Biopharmaceutical: Employment. Samulski:Asklepios Biopharmaceutical: Employment, Patents & Royalties.


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