Blocking Protein S Improves Hemostasis in Hemophilia a and B

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 79-79
Author(s):  
Luca Bologna ◽  
Raja Prince ◽  
Mirko Manetti ◽  
Daniela Melchiorre ◽  
Irene Rosa ◽  
...  

Abstract Introduction&Aim Hemophilia A and B are X-linked disorders caused by an absence or a reduction in coagulation FVIII and respectively, FIX. Patients with hemophilia often suffer from spontaneous bleeding within the musculoskeletal system, such as hemarthrosis. Here, we investigated whether targeting protein S (PS) could promote hemostasis in hemophilia by re-balancing coagulation. PS is a natural anticoagulant, acting as non-enzymatic cofactor for activated protein C (APC) in the inactivation of FVa and FVIIIa, and for tissue factor pathway inhibitor (TFPI) in the inhibition of FXa. This dual role makes PS a key regulator of the inhibition of thrombin generation (TG). Methods & Results Hemophilic (F8-/- or F9-/-) Pros1+/- mice were intercrossed. F8-/-Pros1-/- and F9-/- Pros1-/- mice were viable and found at the expected Mendelian frequency with no increased mortality compared to hemophilic mice. F8-/-Pros1-/- mice did not show DIC onset neither an increased mortality once challenge with tissue factor (TF). Ex vivo evaluation of TG potential showed that F8-/-Pros1-/- mice were APC-resistant, they had an improved low TF induced-TG and a 20% more dense fibrin network with larger fibrin fibers diameter as compared to F8-/-mice. Comparable results were found in human HA plasma where blocking PS raised TG even in the presence of high inhibitor titer. To assess the in vivo effect of PS inhibition on HA mice hemostasis, two tail- clipping (TC) assays were used. In both, mild TC model (2 mm cut) and severe TC (4 mm cut), blood loss significantly decreased in F8-/-Pros1-/- compared to F8- /- mice (mild TC: 407±21 vs 661±29ul, p<0.0001; severe TC:173±14 vs 249±24ul, p<0.05). In addition, the infusion of anti-hPS antibody on F8-/-Pros1+/- mice, reduced the blood loss compared to F8-/-Pros1+/- mice infused with an isotype IgG (196±10 vs 302±25ul, p=0.005). As recurrent joint bleeding is the most common manifestation of HA, we challenged F8-/-Pros1-/- mice in an acute hemarthrosis (AH) model. Joint swelling 72 hours after injury was reduced in F8-/-Pros1-/- compared to F8-/- (0.11±0.03 vs 1.02±0.07mm, p<0.0001, n=10). These results were also confirmed by s.c. injection of anti-hPS antibody (0.46±0.0 vs 0.78±0.09mm isotype IgG, p=0.02, n=9) and by i.v. injection of PS-siRNA prior to AH challenge in F8-/-Pros1+/- (0.29±0.09 vs 0.92±0.12mm siRNA control, p=0.03, n=5) and F8-/- mice(0.35±0.08 vs 0.78±0.09mm siRNA control, p=0.05, n=5). Similar results were obtained in F9-/-Pros1-/- mice. Histological analysis of joint showed joint bleeding reduction in F8-/-Pros1-/- compared to F8-/- and an increased fibrin staining comparable to F8+/+ mice.To understand the intra-articular hemostatic effect of blocking PS, joint sections were stained for TFPI. Preliminary results indicate a massive staining in the synovia of F8-/- mice, while F8-/-Pros1-/- and F8+/+ mice present a less intense signal. These data suggest that the intra-articular space is a modulable anticoagulant environment. Human HA joint tissues were then analyzed for both PS and TFPI. A strong signal was found for TFPI and PS in the synovial lining and sublining layers of HA patients on demand (n=7). Interestingly, PS and TFPI stainings were remarkably decreased in HA patients under prophylaxis (n=5). Joint section from osteoarthritis patients (n=7) did not show an intense staining for TFPI and PS similarly to hemophilic patients under prophylaxis. To understand the improved phenotype of F8-/-Pros1-/- after AH, the function of macrophages were investigated. At the steady state, F8-/-Pros1-/- presented significantly 2-fold increased levels of inflammatory macrophages (M1) than in F8-/- mice. In addition bone marrow derived macrophages from F8-/-Pros1-/- exhibit 10-fold higher RBC phagocytic activity than F8-/- . Preliminary results indicate an increase of a monocyte attractant MCP-1 level, in knee lavage after AH in F8-/-Pros1-/- than F8-/- mice. Conclusion These data provide the first evidence that blocking PS has the ability to ameliorate hemophilia as judged by in vivo improvement of bleeding phenotype in the TC assay as well as in the AH model, suggesting a new valuable tool for hemophilia therapy. In addition, the modulable presence of PS and TFPI in human and mice joints is a novel pathophysiological aspect of hemarthrosis and constitutes a potential therapeutical target. Disclosures Kremer Hovinga: NovoNordisk: Membership on an entity's Board of Directors or advisory committees, Research Funding; CSL-Behring: 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.

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 2304-2304
Author(s):  
Luigi Solimeno ◽  
Steven R. Lentz ◽  
Irina Matytsina ◽  
Niels Zeuthen ◽  
Faraizah Abdul Karim ◽  
...  

Abstract Introduction Recombinant factor VIII can be used to provide hemostatic coverage during surgery in patients with hemophilia A (Santagostino E, et al. Haemophilia 2015;21(1):34-40). Turoctocog alfa is a third-generation, human recombinant B-domain truncated FVIII molecule that has previously been found to be safe and effective in a limited number of patients with hemophilia A undergoing surgery (Santagostino, et al. Haemophilia 2015;21(1):34-40). We report new, previously unreported data that support and extend the findings of this publication. Objectives The primary objective was to assess the clinical safety and hemostatic effect of turoctocog alfa in patients with severe hemophilia A (FVIII ≤1%) undergoing surgery in the ongoing guardian™2 clinical trial (interim cut-off date, 31 December 2013). Hemostatic outcomes were assessed according to a predefined 4-point scale: excellent, good, moderate, none. Secondary objectives included consumption of turoctocog alfa; comparison of actual and anticipated blood loss; hemoglobin level prior to, during, and after surgery; and use of blood-product transfusions. Methods A total of 57 procedures were performed in 40 patients aged 2-57 years with severe hemophilia A and no history of inhibitors (patients <12 years and ≥12 years had ≥50 and ≥150 exposure days prior to surgery, respectively). Before, during, and after surgery, turoctocog alfa dosing was at the investigators' discretion. Only 1 patient received continuous infusion during surgery. In 12 major (9 orthopedic) and 3 minor surgeries on 15 patients (aged 6-56 years) data on hemostatic outcomes were collected during and after surgery (5 of the major surgeries have been presented previously [Santagostino E, et al. Haemophilia 2015;21(1):34-40]). In 42 other surgical procedures (those requiring <7 days of surgery-related treatment with turoctocog alfa) on 31 patients (aged 2-57 years), data were collected during the procedure only. Results Turoctocog alfa provided successful (defined as 'excellent' or 'good' hemostatic outcome) coverage in 15/15 (100%) major or minor surgeries where data were collected during and after surgery. Successful outcomes were reported in 41/42 (98%) other surgical procedures; 1 endoscopy procedure was not provided with a rating. None of the patients developed FVIII inhibitors during the surgery period, and no safety concerns were observed when reviewing adverse events, consumption of turoctocog alfa, blood loss, hemoglobin levels, or use of blood-product transfusions. Conclusions The success rate for hemostatic response during both major and minor surgeries was 100%. No inhibitors or other safety concerns were identified. Turoctocog alfa has a favorable efficacy and safety profile that makes it suitable for use in patients with severe hemophilia A undergoing surgery. Disclosures Solimeno: Novo Nordisk: Speakers Bureau; Baxter: Consultancy, Speakers Bureau. Lentz:Novo Nordisk: Consultancy, Research Funding. Matytsina:Novo Nordisk: Employment. Zeuthen:Novo Nordisk: Employment. Santagostino:CSL Behring: Membership on an entity's Board of Directors or advisory committees, Research Funding; Biotest: Speakers Bureau; Grifols: Membership on an entity's Board of Directors or advisory committees; Novo Nordisk: Membership on an entity's Board of Directors or advisory committees; Baxter: Membership on an entity's Board of Directors or advisory committees; Bayer: Membership on an entity's Board of Directors or advisory committees; Pfizer: Research Funding; Octapharma: Speakers Bureau; Kedrion: Speakers Bureau; Biogen/Sobi: Membership on an entity's Board of Directors or advisory committees.


Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 3190-3190
Author(s):  
Koichiro Yoneyama ◽  
Kazuo Tokuda ◽  
Tetsuhiro Soeda ◽  
Tomohisa Saito ◽  
Midori Shima

Abstract INTRODUCTION: Emicizumab is a bispecific antibody that mimics the cofactor function of activated factor VIII (FVIIIa) and is currently indicated for routine prophylaxis of bleeds in patients with congenital hemophilia A (PwCHA) regardless of factor VIII (FVIII) inhibitor status. Given its mechanism of action, the treatment response of emicizumab is expected to be similar between PwCHA and patients with acquired hemophilia A (AHA; PwAHA). However, it has not been well evidenced. We aimed to address this question by elucidating whether a healthy volunteer (HV)-derived, FVIII-neutralized, AHA-mimetic plasma produces similar pharmacodynamic (PD) responses of emicizumab to those in PwCHA. METHODS: In the phase I-I/II studies of emicizumab (Blood 2016;127:1633-41; N Engl J Med 2016;374:2044-53; Blood Adv 2017;1:1891-9; Haemophilia 2021;27:81-9), 40 Japanese HVs, 24 Caucasian HVs, 11 Japanese PwCHA with inhibitors (PwCHAwI), and 7 Japanese PwCHA without inhibitors (PwCHAwoI) were enrolled to receive emicizumab or placebo. These studies were conducted in accordance with relevant ethical standards as previously reported. Plasma samples were collected before first administration of the study drug, and they were spiked with emicizumab at 0, 0.3, 3, 30, or 300 μg/mL for HVs or 0, 3, or 300 μg/mL for PwCHA in combination with two anti-FVIII neutralizing antibodies (VIII-2236, anti-A2 type 1 inhibitor; VIII-9222, anti-C2 type 2 inhibitor) at approximately 300 μg/mL each (termed "ex vivo spiked plasma") for the measurement of activated partial thromboplastin time (APTT) and activated factor XI-triggered thrombin generation (TG). Separate plasma samples were collected before and after first administration (termed "in vivo exposed plasma") to be used for measuring APTT and TG, with ex vivo FVIII neutralization for HVs or without for PwCHA, as well as emicizumab concentration. Due to the difference in the given dosing regimens, observed plasma emicizumab concentrations did not largely overlap between HVs and PwCHA (up to 5.92 μg/mL as mean maximum concentration in HVs versus 10.3 to 120 μg/mL as mean steady-state trough concentration in PwCHA), which precluded simple comparison of the concentration-response (C-R) relationships between HVs and PwCHA in the in vivo exposed plasma. To overcome this limitation, nonlinear mixed-effect ("population") modeling was performed to analyze the C-R data from the ex vivo spiked plasma from HVs for APTT and TG each, and the developed population PD (PopPD) models were used to simulate C-R relationships in HVs over a wide range of plasma emicizumab concentration for comparison with those observed in the in vivo exposed plasma from PwCHA. RESULTS: In the ex vivo spiked plasma, the observed C-R relationships of APTT and TG were similar among Japanese HVs, Caucasian HVs, Japanese PwCHAwI, and Japanese PwCHAwoI, indicating similar FVIIIa-mimetic activity of emicizumab between HVs and PwCHA under the artificial FVIII-depleted condition ex vivo. The developed PopPD models adequately described the C-R data from HVs which were used for the model development. In the in vivo exposed plasma (Figure), the observed C-R relationships of APTT and TG were similar between Japanese HVs and Caucasian HVs as well as between Japanese PwCHAwI and Japanese PwCHAwoI. The observed C-R relationships in HVs were well captured by the PopPD model-based simulations despite these data being not directly used for the model development, which demonstrated the ability of the ex vivo data to be extrapolated in vivo. The PopPD models also well captured the observed C-R relationships in PwCHA, suggesting similar FVIIIa-mimetic activity of emicizumab between HVs and PwCHA in vivo. Some deviating observations from the PopPD model-based simulations might be attributed to the residual activity of given coagulation factor products, e.g., relatively short APTT and promoted TG at a plasma emicizumab concentration of 0 μg/mL (before first administration) in PwCHAwoI prior treated with FVIII prophylaxis. CONCLUSIONS: A HV-derived, FVIII-neutralized, AHA-mimetic plasma produced similar PD responses of emicizumab to those in PwCHA with or without inhibitors. Given its potential nature of mimicking AHA, i.e., coexistence of FVIII and multiple inhibitors including a type 2 one, the findings derived using this plasma may suggest similarity in the treatment response of emicizumab between PwCHA and PwAHA. Figure 1 Figure 1. Disclosures Yoneyama: Chugai Pharmaceutical Co., Ltd.: Current Employment, Patents & Royalties: Inventor of patents related to anti-FIXa/FX bispecific antibodies. Tokuda: Chugai Pharmaceutical Co., Ltd.: Current Employment. Soeda: Chugai Pharmaceutical Co., Ltd.: Current Employment, Patents & Royalties: Inventor of patents related to anti-FIXa/FX bispecific antibodies. Saito: Chugai Pharmaceutical Co., Ltd.: Current Employment. Shima: BioMarin Pharmaceutical Inc.: Membership on an entity's Board of Directors or advisory committees; Bayer AG: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novo Nordisk A/S: Honoraria, Speakers Bureau; Takeda: Research Funding; CSL Behring: Research Funding, Speakers Bureau; F. Hoffmann-La Roche Ltd.: Membership on an entity's Board of Directors or advisory committees; Chugai Pharmaceutical Co., Ltd.: Consultancy, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties: Inventor of patents related to anti-FIXa/FX bispecific antibodies, Research Funding, Speakers Bureau; Sanofi S.A.: Speakers Bureau; Fujimoto Seiyaku: Consultancy, Speakers Bureau. OffLabel Disclosure: Emicizumab for acquired hemophilia A


Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 43-45
Author(s):  
Kate Khair ◽  
Francis Nissen ◽  
Mariabeth Silkey ◽  
Tom Burke ◽  
Aijing Shang ◽  
...  

Introduction: Hemophilia A (HA) is a congenital bleeding disorder, caused by a deficiency in clotting factor VIII (FVIII) and characterized by uncontrolled bleeding and progressive joint damage. This analysis assesses the impact of disease burden on the daily life of children with hemophilia A (CwHA) and their caregivers, addressing a deficit of current research on this topic. Methods: The Cost of Haemophilia in Europe: a Socioeconomic Survey in a Paediatric Population (CHESS Paediatrics) is a retrospective, burden-of-illness study in children with moderate and severe HA (defined by endogenous FVIII [IU/dL] relative to normal; moderate, 1-5%; severe, &lt;1%) across France, Germany, Italy, Spain and the UK. CwHA were recruited and stratified by both age group (0-5 years:6-11 years:12-17 years=1:1:1) and disease severity (severe:moderate=approximately 2:1, prioritizing children with severe HA [CwSHA]). Data for this analysis were captured from physicians, children, and their caregivers. Physicians completed online case report forms for treated children, and the child and/or their caregivers completed a paper-based questionnaire utilizing 5-point Likert scales. For CwHA aged 0-7, the questionnaire was completed by the caregiver, while for CwHA aged 8-17, children and caregivers completed different sections. Hours of care provided by the caregiver and work lost by the caregiver were reported as median values due to non-normal data distribution. Informed consent was obtained for all participants. Upon review, the study was approved by the University of Chester ethical committee. Results: Data from child/caregiver questionnaires were available for 196 CwHA (moderate, 25.5%; severe, 74.5%); the majority of these children, as expected, were receiving prophylaxis (72.4%), and did not have FVIII inhibitors (89.8%; Table 1). There was a direct impact of disease burden on CwHA, particularly with regard to physical and social activities (Figure 1). Overall, it was agreed or strongly agreed by the child or caregiver that 48.0% and 57.5% of children with moderate HA (CwMHA) and CwSHA respectively, have reduced physical activity due to HA, and 46.0% and 57.5%, respectively, have reduced social activity due to HA. A total of 36.0% and 61.0% of CwMHA and CwSHA, respectively, had adapted their treatment in anticipation of physical or social activity (Table 1). Furthermore, 34.0% of CwMHA and 55.4% of CwSHA were frustrated due to their disease, and many (CwMHA, 36.0%; CwSHA, 50.7%) felt that they had missed opportunities (Figure 1). For 66.0% of CwMHA and 76.0% of CwSHA, it was reported that their daily life was compromised due to their HA. Caregivers provided a median (interquartile range [IQR]) of 19.0 (10.0-59.5) and 12.0 (5.0-20.0) hours a week of care for the hemophilia-related needs of their CwMHA (n=30) or CwSHA (n=105), respectively. Of those who responded, 17.4% (n=4/23) and 25.0% (n=20/80) of caregivers to CwMHA or CwSHA, respectively, stated they have lost work due to their caregiving duty. This was more than twice as common for caregivers in families with multiple CwHA (42.9%, n=9/21 responses) compared with those in families with one CwHA (18.5%, n=15/81 responses). Median (IQR) hours of work per week estimated to be lost were 20.0 (17.0-22.0) for caregivers of CwMHA (n=4) and 12.5 (4.50-20.0) for caregivers of CwSHA (n=20). Conclusions: In conclusion, both children and caregivers make sacrifices in their daily lives due to HA; many CwHA reported reduced physical and social activities, fewer opportunities and feelings of frustration due to their HA. Caregivers reported spending a significant number of hours caring for their child and some reported losing work due to their caring responsibilities. However, some outcomes may be limited by the small number of respondents and narrow response options, particularly those regarding the caregiver burden. Responses on the hours of work lost may be subject to selection bias, as caregivers who have lost work may be more likely to respond to this question. Additionally, as this question is targeted at caregivers in employment, it is unknown if some caregivers have left employment due to their caregiving responsibilities. According to this analysis, children/caregivers are frequently required to adapt the child's treatment before the child engages in activities. Overall, the burden of disease was similar in children with moderate and severe HA. Disclosures Khair: Takeda: Honoraria, Speakers Bureau; Bayer: Consultancy, Honoraria, Speakers Bureau; Biomarin: Consultancy; HCD Economics: Consultancy; Novo Nordisk: Consultancy, Membership on an entity's Board of Directors or advisory committees; Medikhair: Membership on an entity's Board of Directors or advisory committees; Sobi: Consultancy, Honoraria, Research Funding, Speakers Bureau; CSL Behring: Honoraria, Research Funding; F. Hoffmann-La Roche Ltd: Honoraria, Research Funding; Haemnet: Membership on an entity's Board of Directors or advisory committees. Nissen:GSK: Research Funding; Novartis: Research Funding; Actelion: Consultancy; F. Hoffmann-La Roche Ltd: Current Employment. Silkey:Aerotek AG: Current Employment; F. Hoffmann-La Roche Ltd: Consultancy. Burke:HCD Economics: Current Employment; University of Chester: Current Employment; F. Hoffmann-La Roche Ltd: Consultancy. Shang:F. Hoffmann-La Roche Ltd: Current Employment, Current equity holder in publicly-traded company, Other: All authors received support for third party writing assistance, furnished by Scott Battle, PhD, provided by F. Hoffmann-La Roche, Basel, Switzerland.. Aizenas:F. Hoffmann-La Roche Ltd: Current Employment, Current equity holder in publicly-traded company. Meier:F. Hoffmann-La Roche Ltd: Current Employment, Current equity holder in publicly-traded company. O'Hara:HCD Economics: Current Employment, Current equity holder in private company; F. Hoffmann-La Roche Ltd: Consultancy. Noone:Research Investigator PROBE: Research Funding; Healthcare Decision Consultants: Membership on an entity's Board of Directors or advisory committees; European Haemophilia Consortium: Membership on an entity's Board of Directors or advisory committees.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 2409-2409
Author(s):  
Tiffany Lin Lucas ◽  
Shveta Gupta ◽  
Joanna A. Davis ◽  
Fernando F. Corrales-Medina

Introduction: With the Federal Drug and Administration approval of the use of emicizumab from birth to adulthood, clinicians will now grapple with when to choose and offer emicizumab for routine prophylaxis, especially in previously untreated patients (PUPs). Given the overall limited real-world reported data and experience using emicizumab in PUPs, we created and administered a survey to medical providers in the United States who care for paediatric patients with haemophilia to investigate real-world practice strategies and treatment selection for PUPs. Methods: After review and endorsement by the Haemostasis and Thrombosis Research Society (HTRS), the survey was electronically distributed by e-mail to all providers included in the HTRS core member list. The survey was also sent to those providers included in a list of Haemophilia Treatment Centre (HTC) physicians (with duplicate emails reconciled). Providers needed to self-identify as ones that treat pediatric patients to be included. The survey was developed as a tiered survey with questions presented to each recipient based on their prior responses. Results: Seventy-seven completed surveys were included and analysed. All participants were active providers at a comprehensive HTC and the majority (93.4%) were practicing at an academically affiliated site. In terms of characteristics of those that answered the survey, forty-eight percent of responders reported that 1-20% of their patients had expressed interest in emicizumab. 46% of participants (34/74) reported that they would personally consider emicizumab as their prophylaxis recommendation for the majority (>50%) of their hemophilia A patients without inhibitors. 57% (44/76) reported that 1-10% of their non-inhibitor hemophilia A patients were already prescribed emicizumab prophylaxis. Each participant was then asked about his or her consideration of emicizumab as prophylaxis therapy for a 2 month old PUP. Just over the majority were unsure or said no to this consideration (51.3%) and their concerns were lack of information on safety and efficacy in this young age group and increased risk for inhibitor development. If the 2 month old PUP had a high risk of inhibitor, the majority of providers who initially were hesitant to start emicizumab prophylaxis would remain so. Of note, those providers went on to be asked if the patient had gone on to complete 50 exposure days without inhibitor development, they would then become more likely to initiate emicizumab prophylaxis therapy. Use of concurrent factor replacement was posed to all participants and there were varied responses. Discussion: Overall, our results reflect a widespread practice variation and a not yet well-standardized or defined approach for the use of emicizumab in PUPs with haemophilia A. In this survey, patient preference and individual bleeding risk were the top reasons for which a provider would consider using switching to emicizumab prophylaxis in both severe and mild/moderate haemophilia A patients. This pattern of practice reflects the current era of individualized medicine. Overall, our findings reinforce the need for more studies to investigate the outcomes of a combined treatment approach with FVIII concentrates and emicizumab focusing in the potential benefit of this approach in decreasing the risk for inhibitor development PUPs. Clinicians also feel the need for further data to help clarifying the safety of emicizumab in this population. Figure Disclosures Gupta: Novartis: Honoraria, Speakers Bureau; CSL Behring: Research Funding; Novo Nordisk: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Octapharma: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda-Shire: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Davis:Sanofi: Membership on an entity's Board of Directors or advisory committees; Kedrion: Membership on an entity's Board of Directors or advisory committees; Novo Nordisk: Membership on an entity's Board of Directors or advisory committees; CSL Behring: Consultancy, Membership on an entity's Board of Directors or advisory committees; Takeda Shire: Consultancy; Spark Therapeutics: Consultancy. Corrales-Medina:Kedrion: Membership on an entity's Board of Directors or advisory committees; Bayer: 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; Octapharma: Membership on an entity's Board of Directors or advisory committees.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 1126-1126
Author(s):  
Karen L. Zimowski ◽  
Glaivy M. Batsuli ◽  
Paulette Bryant ◽  
Jenny McDaniel ◽  
Kelly Tickle ◽  
...  

Introduction : Emicizumab is a novel humanized bispecific antibody that mimics the function of activated coagulation factor VIII (fVIII). It has significantly changed the management of patients with hemophilia A and inhibitors by achieving baseline hemostatic control. Based on the HAVEN studies, emicizumab markedly reduces annualized bleeding rates and is FDA-approved for prophylaxis in hemophilia A patients of all ages, regardless of inhibitor status. In the HAVEN2 interim analysis, only 3/57 pediatric patients receiving emicizumab prophylaxis required treatment for an acute bleeding event after a 9-week median observation time. We report 3 patients with severe hemophilia A and a history of inhibitors receiving emicizumab prophylaxis with severe or refractory bleeding episodes to highlight the importance of vigilance and surveillance of children with severe hemophilia A on emicizumab. Methods: This retrospective analysis includes patients between 0-21 years of age with severe hemophilia A (fVIII activity < 1%) receiving emicizumab prophylaxis and admitted for the management of an acute bleeding episode following emicizumab's FDA approval in November 2017. Patients were followed at the Pediatric Hemophilia Treatment Center at the Hemophilia of Georgia Center for Bleeding & Clotting Disorders of Emory and the St. Jude Affiliate Clinic at Novant Health Hemby Children's Hospital. Data collected included demographics, past medical history including inhibitor status, bleeding history, and treatment modalities, and details regarding the presentation, management, and outcome of acute severe bleeding events. Due to the nature of the study, descriptive statistics were primarily used for data analysis. Results: Three patients with severe hemophilia A receiving emicizumab prophylaxis were admitted for the management of 4 severe bleeding episodes. All patients had a history of a fVIII inhibitor. Three of the 4 bleeding episodes were trauma-induced while 1 occurred spontaneously. For the traumatic episodes, all patients presented with worsening symptoms approximately 1 week following the inciting event. All patients had a normal aPTT at the time of presentation, ruling out a significant anti-drug antibody (emicizumab level not available). A patient with a low-titer inhibitor developed an epidural hematoma following a trampoline injury and was treated with continuous infusion of recombinant factor VIII (rfVIII), adjusting the rate to achieve chromogenic fVIII activity of 100% for 14 days. Following 14 days, he was started on rfVIII 50 IU/kg Q12 hours with a goal fVIII activity of 50%. His rfVIII dosing interval was gradually weaned to every other day while in inpatient rehabilitation. As outlined in Table 1, the remaining 3 bleeding events were initially managed with recombinant activated factor VII (rfVIIa) dosed at 80-90 mcg/kg/dose with escalating frequency for an average of 8 days. However, due to lack of improvement, treatment was changed to low-dose activated prothrombin complex concentrates (aPCC; 10-15 IU/kg/dose Q12-24 hours for an average of 7 days). In all 3 of these events, the hematomas improved after treatment with aPCC. No patient experienced thrombotic microangiopathy, thrombosis, or had evidence of DIC while receiving these treatment regimens. Discussion/Conclusion: Pharmacokinetic analysis of emicizumab suggests that following the standard 4-week loading phase, trough plasma emicizumab concentrations obtained prior to a 1.5 mg/kg once weekly maintenance dose correlates with at least 10-15 IU/dL equivalent fVIII activity. This degree of thrombin generation should be sufficient to prevent severe spontaneous bleeding episodes in most patients. However it does not preclude significant trauma-induced bleeding or spontaneous bleeding in inhibitor patients. Based on our cases, providers should maintain a high index of suspicion for acute bleeding in patients receiving emicizumab prophylaxis. Serious bleeding events, although rare, may have a more insidious onset in patients receiving emicizumab. Furthermore, despite the baseline hemostasis achieved with emicizumab, acute bleeding events may still require aggressive therapy. Our cases suggest that low-dose aPCC or continuous infusion fVIII may be feasible options for treating acute bleeding events in patients with hemophilia A and inhibitors receiving emicizumab prophylaxis. Disclosures Zimowski: Pfizer: Research Funding; National Hemophilia Foundation: Other: Medical Loan Reimbursement, Research Funding. Batsuli:Octapharma: Membership on an entity's Board of Directors or advisory committees; Bayer: Membership on an entity's Board of Directors or advisory committees; Genetech: Membership on an entity's Board of Directors or advisory committees. Bryant:Novo Nordisk: Other: PI on Novo Nordisk sponsored Studies. McDaniel:Genentech: Membership on an entity's Board of Directors or advisory committees. Tickle:National Hemophilia Foundation: Research Funding. Meeks:Bayer: Membership on an entity's Board of Directors or advisory committees; Genentech: Membership on an entity's Board of Directors or advisory committees; Novo Nordisk: Membership on an entity's Board of Directors or advisory committees; Bioverativ: Membership on an entity's Board of Directors or advisory committees; Takeda-Shire: Membership on an entity's Board of Directors or advisory committees; HEMA Biologics: Membership on an entity's Board of Directors or advisory committees. Sidonio: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; Grifols: Membership on an entity's Board of Directors or advisory committees, Research Funding; Biomarin: Membership on an entity's Board of Directors or advisory committees; 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; Kedrion: Research Funding.


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 514-514 ◽  
Author(s):  
Bin Zhang ◽  
David Irvine ◽  
Yin Wei Ho ◽  
Silvia Buonamici ◽  
Paul Manley ◽  
...  

Abstract Abstract 514 Background: Tyrosine kinase inhibitors (TKI), although effective in inducing remissions and improving survival in CML patients, fail to eliminate leukemia stem cells (LSC), which remain a potential source of relapse on stopping treatment. Additional strategies to enhance elimination of LSC in TKI-treated CML patients are required. The Hedgehog (Hh) pathway, important for developmental hematopoiesis, has been shown to be activated in BCR-ABL-expressing LSC, in association with upregulation of Smoothened (SMO), and contributes to maintenance of BCR-ABL+ LSC. However the role of Hh signaling in chronic phase (CP) CML LSC is not clear. LDE225 (LDE, Novartis Pharma) is a small molecule SMO antagonist which is being clinically evaluated in patients with solid tumors. We have reported that LDE does not significantly affect proliferation and apoptosis of primary CP CML CD34+ cells, or reduce colony growth in CFC assays, but results in significant reduction in CML CFC replating efficiency and secondary colony formation. Treatment with LDE + Nilotinib resulted in significant reduction in colony formation from CD34+ CML cells in LTCIC assays compared to Nilotinib alone or untreated controls. These observations suggest that LDE may preferentially inhibit growth of primitive CML progenitors and progenitor self-renewal. We therefore further investigated the effect of LDE on growth of primitive CML LSC in vivo. Methods and Results: 1) CP CML CD34+ cells were treated with LDE (10nM), Nilotinib (5μ M) or LDE + Nilotinib for 72 hours followed by transplantation into NOD-SCID γ-chain- (NSG) mice. Treatment with LDE + Nilotinib resulted in reduced engraftment of CML CD45+ cells (p=0.06) and CD34+ cells (p=0.02) compared with controls, and significantly reduced engraftment of CML cells with CFC capacity (p=0.005). In contrast LDE or Nilotinib alone did not reduce CML cell engraftment in the bone marrow (BM) compared with untreated controls. LDE, Nilotinib, or LDE + Nilotinib treatment did not significantly inhibit engraftment of normal human CD34+ cells in NSG mice compared to controls. 2) We also used the transgenic Scl-tTa-BCR-ABL mouse model of CP CML to investigate the effect of in vivo treatment with LDE on CML LSC. BM cells from GFP-SCL-tTA/BCR-ABL mice were transplanted into wild type congenic recipients to establish a cohort of mice with CML-like disease. Recipient mice developed CML-like disease 3–4 weeks after transplantation. Transplanted CML cells were identifiable through GFP expression. Mice were treated with LDE225 (80mg/kg/d by gavage), Nilotinib (50 mg/kg/d by gavage), LDE + Nilotinib, or vehicle alone (control) for 3 weeks. Treatment with Nilotinib, LDE, and LDE + Nilotinib resulted in normalization of WBC and neutrophil counts in peripheral blood. LDE + Nilotinib treatment significantly reduced the number of splenic long term hematopoietic stem cells (LT-HSC, Lin-Sca-1+Kit+Flt3-CD150+CD48-, p<0.01) and granulocyte-macrophage progenitors (GMP) compared to controls, but did not significantly alter LT-HSC numbers in the BM. LDE alone reduced splenic LT-HSC but not GMP, whereas Nilotinib alone did not reduce LT-HSC numbers in spleen or BM but significantly reduced splenic GMP numbers. The mechanisms underlying enhanced targeting of LSC in the spleen compared to the BM are not clear but could reflect greater dependence on Hh signaling in the context of the splenic microenvironment and/or relocalization of LDE treated LT-HSC to BM. Experiments in which BM and spleen cells from treated mice were transplanted into secondary recipients to determine functional stem cell capacity of remaining LT-HSC are ongoing. Importantly mice treated with LDE + Nilotinib demonstrated enhanced survival on follow up after discontinuation of treatment compared with control mice or mice treated with LDE or Nilotinib alone. Conclusions: We conclude that LDE225 can target LSC from CP CML patients and in a transgenic BCR-ABL model of CP CML, and that LDE + Nilotinib treatment may represent a promising strategy to enhance elimination of residual LSC in TKI-treated CML patients. Disclosures: Buonamici: Novartis: Employment. Manley:Novartis: Employment. Holyoake:Novartis: Consultancy, Research Funding. Copland:Novartis Pharma: Honoraria, Research Funding; Bristol-Myers Squibb: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees. Bhatia:Novartis: Consultancy, Honoraria.


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 27-27 ◽  
Author(s):  
Cindy A. Leissinger ◽  
Rebecca Kruse-Jarres ◽  
Suzanne Granger ◽  
Barbara A Konkle ◽  
Margaret V. Ragni ◽  
...  

Abstract Abstract 27 Antibodies (inhibitors) to exogenously administered factor VIII (FVIII) develop in as many as 30 – 40% of patients with severe hemophilia A. Patients with persistent inhibitors are at increased risk of serious, poorly controlled bleeding which results in significant morbidity and in some cases early death. Rituximab, a chimeric murine/human monoclonal antibody directed against CD20, suppresses circulating and tissue B cells and pre-B cells and has been used in the treatment of a variety of autoimmune and alloimmune disorders. The primary objective of this NHLBI Transfusion Medicine Hemostasis network-sponsored study was to evaluate the role of rituximab as an approach to inhibit the production of FVIII antibodies in patients with severe congenital hemophilia A and high titer inhibitors. Methods: This was a prospective, multi-institution, single-arm, open-label Phase II trial. Eligible subjects were males over 18 months of age with severe hemophilia A and a history of an inhibitor ≥5 Bethesda units (BU). Individuals who were HIV positive, undergoing immune tolerance, or receiving immune modulating therapies were excluded. Following a challenge dose of recombinant FVIII (rAHF-PFM) at 50 IU/kg, and evidence of an inhibitor titer ≥ 5 BU at 5 – 14 days after the challenge dose, subjects received rituximab 375 mg/m2 weekly for 4 weeks. Starting two weeks after the fourth rituximab treatment, inhibitor titers were drawn every 4 weeks. A major response was defined as a fall in the inhibitor titer to < 5 BU at any time up to and including week 22, with the titer remaining < 5 BU following re-challenge with FVIII. A minor response was defined as inhibitor falling to < 5 BU at any time up to and including week 22, with the anamnestic peak following re-challenge with FVIII between 5–10 BU and less than 50% of the original anamnestic peak. The null hypothesis was that no more than 5% of subjects treated with rituximab would be major responders. Results: A total of 23 subjects were enrolled; 21 received the initial FVIII challenge. Of these, 4 subjects did not meet the criteria to receive rituximab treatment, and 1 subject withdrew consent. A total of 16 subjects received at least one dose of rituximab and are included in this analysis. The median age was 14 y (range 4 – 38 y). Three subjects (18.8%) had a major response. If the null hypothesis were true, the probability of 3 or more major responses in 16 subjects would be 0.043, so the null hypothesis was rejected. One subject (6.2%) had a minor response to treatment. All 4 responders and 8 non-responders had a baseline inhibitor titer < 20 BU, resulting in a response rate of 33% in that group vs. 0% in the 4 subjects with a baseline inhibitor titer ≥ 20 BU. Discussion: Infusion of rituximab 375 mg/m2 once per week for four weeks was effective in reducing the anamnestic inhibitor response in 25% of severe hemophilia A subjects with inhibitors who were not receiving concurrent immune tolerance therapy. Those who responded tended to have lower baseline inhibitor levels compared to the group that did not meet the criteria for response. This Phase II study, designed as a proof of concept, demonstrated that rituximab may be useful in lowering inhibitor levels and anamnesis in some patients with inhibitors, but that the effect as a solo treatment strategy is modest, and possibly restricted to patients with inhibitor titers under 20 BU. Further studies are indicated to determine the role of rituximab as an adjunctive therapy in immune tolerization strategies. Acknowledgments: The authors acknowledge the support of Genentech for the provision of rituximab and partial financial support for the study. The authors also acknowledge Baxter Healthcare Corporation for donating the recombinant FVIII used in the trial. Disclosures: Leissinger: Baxter: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Off Label Use: Rituximab, a drug approved for use in treating lymphoma, was studied for its efficacy in suppressing inhibitors against factor VIII in patients with hemophilia and high titer inhibitors. Kruse-Jarres:Baxter: Consultancy, Honoraria; Bayer:; Griforls: Consultancy, Honoraria; Inspiration: Consultancy, Honoraria; NovoNordisk: Consultancy, Honoraria. Konkle:Baxter Corporation: Consultancy, Research Funding; Bayer Corp: Consultancy; Inspiration Biopharmaceuticals: Research Funding; CSL Behring: Consultancy, Membership on an entity's Board of Directors or advisory committees. Neufeld:Genentech: Research Funding; Baxter: Research Funding; Bayer: Research Funding. Bennett:Biogen IDEC: Honoraria. Valentino:Baxter Bioscience, Bayer Healthcare, GTC Biotherapeutics, NovoNordisk, Pfizer, CSL Behring, Inspiration Bioscience, and Biogen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding.


Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 206-206 ◽  
Author(s):  
Rebecca Kruse-Jarres ◽  
Jean St. Louis ◽  
Anne Greist ◽  
Amy D. Shapiro ◽  
Hedy Smith ◽  
...  

Abstract Introduction Acquired hemophilia A (AHA) is a rare bleeding disorder, resulting from auto-antibodies to human factor VIII (hFVIII). The challenges created by the management of AHA and the co-morbidities present in this typically elderly population, can be managed by a recombinant, highly pure, B-domain deleted, porcine sequence FVIII (OBI-1) that is not generally susceptible to the inhibitory activity of anti-human FVIII antibodies. Treatment with OBI-1 allows for monitoring of FVIII levels which provides a reproducible and objective surrogate predictor of hemostasis. Eradication of hFVIII inhibitors with immunosuppressive therapy is critical for disease management. During immunosuppression, the patient transitions from a bleeding state at initial presentation to a relative hypercoagulable state which can be an issue in patients who are susceptible to thromboembolic events due to their comorbidities. This transition period is of most concern especially when using traditionally utilized bypassing agents that cannot be monitored. OBI-1 enables measurement of FVIII levels, guiding dosing and enhancing treatment safety during this critical period. Methods This global, prospective, multi-center phase 2/3 open label clinical trial investigates the efficacy and safety of OBI-1 in the treatment of serious bleeds in adults with AHA conducted under ICH guidelines and local IRB/Ethics Committee oversight. Primary efficacy endpoint was assessed at 24 hours (eg. effective, partially effective). All subjects (N= 18) presented with a serious bleed and were treated with an initial dose of OBI-1 (200 U/kg), followed by additional doses based on the subject's target factor VIII levels, anti-OBI-1 titer, and clinical factors. Results In all 18 subjects, a positive response (14 effective/4 partially effective) to treatment was observed at 24 hours. This positive response to OBI-1 treatment was seen by 8 hours in 14/18 of the subjects and at 16 hours in 16/18 of the subjects. Median total exposure to OBI-1 per subject was 1782.5 U/kg. The median total first dose was 14,000 U. For subjects who received additional doses of OBI-1, the median dose was reduced from the initial dose, but did not differ considerably over subsequent doses (9180 to 13561 U; median 11000 U). The majority of subjects (17/18) received concomitant immunosuppressive therapies. No related serious adverse reactions occurred. Non-serious adverse events related to treatment were noted in 5/18 (27.8%) subjects. One subject had mild tachycardia, hypotension and constipation. One subject had 2 instances of mild PICC line occlusion. One subject had a mild hypofibrogenemia. All of these adverse effects completely resolved. Three subjects developed anti-porcine inhibitors after infusion of study drug (range 8-108 BU) and two were discontinued from treatment. Anti-porcine inhibitors were detected prior to infusion in 6/18 patients (range 0.8-29 BU). All of these subjects had a favorable clinical response at 24 hours post-OB-1 infusions. Conclusions Data from this prospective study demonstrate OBI-1 as a safe and effective treatment of bleeding episodes in patients with AHA, with the added advantage over other bypass therapies of allowing FVIII monitoring throughout treatment and healing phase. Disclosures: Kruse-Jarres: Baxter Healthcare: Consultancy; Bayer HealthCare: Consultancy; Biogen IDEC: Consultancy; Grifols: Consultancy; Kedrion: Consultancy; Novo Nordisk: Consultancy. St. Louis:CSL Behring: Research Funding; Octapharma: Consultancy, Research Funding; Baxter: Consultancy; Novo Nordisk: Honoraria. Shapiro:Kedrion Biopharma: Consultancy; Chugai Pharma USA: Consultancy; Biogen IDEC: Consultancy, Membership on an entity’s Board of Directors or advisory committees; Bayer HealthCare: Membership on an entity’s Board of Directors or advisory committees; Novo Nordisk: Consultancy, Membership on an entity’s Board of Directors or advisory committees; Baxter Healthcare: Consultancy, Membership on an entity’s Board of Directors or advisory committees. Chowdary:Baxter Healthcare: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Travel grant Other; Novo Nordisk: Honoraria, Research Funding, Travel grant, Travel grant Other; Bayer HealthCare: Honoraria, Travel grant, Travel grant Other; Pfizer: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding, Travel grant, Travel grant Other; CSL Behring: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding, Travel grant Other; Biogen IDEC: Honoraria, Travel, Travel Other. Drebes:Octapharma: Travel grant Other; CSL Behring: Travel grant, Travel grant Other; Leo-pharma: Travel grant, Travel grant Other; Bayer Healthcare: Consultancy, Honoraria. Gomperts:Baxter Healthcare: Consultancy; Asklepios Biopharmaceutoicals Inc: Consultancy; Cangene Inc: Consultancy. Chapman:Baxter Healthcare: Employment. Mo:Baxter Healthcare: Employment. Novack:Baxter Healthcare: Employment. Farin:Baxter Healthcare: Employment.


Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 297-297 ◽  
Author(s):  
Colleen Delaney ◽  
Filippo Milano ◽  
Ian Nicoud ◽  
Shelly Heimfeld ◽  
Chatchada Karanes ◽  
...  

Abstract Introduction There is a strong clinical need to overcome the increased early non relapse mortality (NRM) associated with delayed neutrophil recovery following cord blood transplant (CBT). Therefore we established a methodology using Notch ligand (Delta1) as a strategy for increasing the absolute number of marrow repopulating CB hematopoietic stem/progenitor cells (HSPC). We previously reported preliminary results of the first 10 patients in 2010 demonstrating the ability of Notch-expanded CB HSPC to provide rapid myeloid recovery post-CBT.1 Herein we present the updated results on 23 patients accrued to this trial aimed at assessment of efficacy as well as the feasibility of overnight shipment of the expanded cell product to three outside institutions. Methods Between July 2006 and March 2013, 23 patients with hematologic malignancies were enrolled in this prospective multi-center Phase I trial coordinated by the Fred Hutchinson Cancer Research Center in which one CB unit was ex vivo expanded prior to infusion. Conditioning consisted of Fludarabine (75mg/m2), Cyclophosphamide (120mg/kg) and TBI (13.2 Gy) over 8 days. On day 0, the unmanipulated CB unit was infused first followed 4 hours later by infusion of the freshly harvested expanded CB cells. Graft versus host disease (GVHD) prophylaxis consisted of cyclosporine and MMF beginning on day -3. All CB grafts were 4-6/6 HLA-matched (A/B antigen level, DRB1 allele level) to the recipient. Engraftment, NRM, relapse and GVHD were calculated using cumulative incidence rates to accommodate competing risks. Overall survival was analyzed using Kaplan-Meier estimates. Results Patient diagnosis was AML (n=16), ALL (n=5) and biphenotypic leukemia (n=2). Nine patients (39%) were ≥CR2 and 5 were MRD+ at the time of transplant. Median age was 28 years (range, 4-43) and weight 70 kg (range, 16-91) with a median follow-up of 614 days (range, 271-2443). 22 patients received the expanded graft with one product not meeting release criteria. The cell doses infused were significantly higher in the expanded CB graft: 2.7 (1.5-6.3) vs 6.9 (0.4-27.6) x107 TNC/kg, p<0.0008; 0.15 (0.02-0.57) vs 7.7 (0.62-49.5) x106 CD34/kg, p<0.0001. HLA-matching and ABO incompatibility of the expanded and unmanipulated products were similar. The incidence of neutrophil recovery was 95% (95% CI, 71-100) at a median of 13 days (range, 6-41 days) among the 22 patients receiving expanded CB cells which is significantly faster than that observed in 40 recipients of two unmanipulated units otherwise treated identically at a median time of 25 days (range, 14 to 45; p<0.0001). The incidence of platelet recovery (>20 x 10^9/L) was 77% (CI 95%: 53- 89) by day 100 at a median of 38 days (range, 19 – 134). There was one case of primary graft failure. Importantly, rate of neutrophil recovery correlated with CD34+ cell dose/kg with 8 out of 11 patients receiving greater than 8x106 CD34+cells/kg achieved an ANC ≥ 500/µl within 10 days. 21 patients were evaluable for in vivo persistence of the expanded cells. Ten (48%) demonstrated in vivo persistence beyond one month post infusion. The expanded cell graft was persistent at day 180 in 7 patients, and in those that survived to one year, dominance of the expanded cell graft persisted in one patient. The incidences of grade II-IV and III-IV acute GVHD was 77% (95% CI, 53-89) and 18% (95% CI, 5-36%), respectively; mild chronic GVHD was observed in 4 patients and severe chronic GVHD in one. Probability of OS was 62% (95% CI, 37-79%) at 4 years. Notably, the cumulative incidence of NRM at day 100 was 8% (95% CI, 14-24%) and at 4 years was 32% (95% CI, 8-40%). Nine patients died at a median time of 216 days (range, 31-1578 days) with respiratory failure/infection the most common cause (n=6). There were two relapses at day 156 and 365 post-transplant, with one death due to relapse. Secondary malignancy and primary graft failure were the other 2 causes of death. Conclusions Infusion of Notch-expanded CB progenitors is safe and effective, significantly reducing the time to neutrophil recovery and risks of NRM during the first 100 days. An advantage for infusion of higher numbers of CD34+ cells/kg further demonstrates the need to develop methods that reproducibly provide even greater expansion of repopulating cells than currently achieved to improve efficacy and potentially cost effectiveness. 1. Delaney C, et al, Nat Med. 2010 Feb;16(2):232-6. Disclosures: Delaney: Novartis: DSMB, DSMB Other; Biolife: Membership on an entity’s Board of Directors or advisory committees; medac: Research Funding. Wagner:Novartis: Research Funding; cord use: Membership on an entity’s Board of Directors or advisory committees.


Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 1413-1413
Author(s):  
Barbara Konkle ◽  
K John Pasi ◽  
David J Perry ◽  
Johnny Mahlangu ◽  
Savita Rangarajan ◽  
...  

Abstract Background: Prophylactic replacement of coagulation factor VIII (FVIII) is the standard of care for patients with hemophilia A; however, prophylaxis with conventional FVIII products usually requires frequent intravenous injections (3-4 times/week). The safety, efficacy, and prolonged half-life of rFVIIIFc in previously treated adults and adolescents (≥12 y) with severe hemophilia A were demonstrated in the phase 3 A-LONG study (NCT01181128, completed) and ASPIRE extension study (NCT01454739, ongoing). Here, we report cumulative long-term data on the safety and efficacy of rFVIIIFc in study participants as of the second interim data cut (8 Dec 2014). Methods: This longitudinal analysis includes cumulative data from A-LONG and ASPIRE (as of the second interim data cut 8 Dec 2014) for subjects treated with ≥1 dose of rFVIIIFc. 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 (ET). Subjects completing A-LONG and meeting enrollment criteria for ASPIRE could participate in the IP, WP, or ET groups, or, if optimal dosing could not be achieved with IP or WP, in an additional modified prophylaxis (MP) group. Subjects could change treatment groups at any point during ASPIRE. Efficacy analyses were performed using data 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 group. Outcomes evaluated included: incidence of inhibitors (neutralizing antibody value ≥0.6 BU/mL identified and confirmed on 2 separate samples drawn approximately 2-4 weeks apart and performed by the central laboratory as measured by the Nijmegen-modified Bethesda assay), adverse events (AEs), annualized bleeding rate (ABR), treatment of acute bleeds, and prophylactic consumption and dosing interval compared to pre-A-LONG (prestudy). Results: Of 164 subjects dosed with rFVIIIFc during A-LONG, 153 completed the study and 150 enrolled in ASPIRE; at the time of this second interim data cut, 97 subjects were ongoing in ASPIRE, 40 subjects had completed the study, and 13 subjects withdrew. Cumulatively, subjects had 38,662 rFVIIIFc exposure days (EDs), inclusive of surgery. As of this second interim data cut (8 Dec 2014), no inhibitors were observed; the type and incidence of adverse events (AEs) observed were typical of previous hemophilia A populations studied. 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 lower with rFVIIIFc compared with prestudy FVIII for subjects on prestudy prophylaxis or ET (Figure). In the IP group, the median (interquartile range [IQR]) spontaneous ABRs in Years 1, 2, and 3 on-study were 0.0 (0.0, 2.0), 0.0 (0.0, 1.0), and 0.0 (0.0, 1.0), respectively. In the WP treatment group, the median (IQR) spontaneous ABRs in Years 1, 2, and 3 on-study were 1.0 (0.5, 3.0), 0.5 (0.0, 2.1), and 0.0 (0.0, 1.0), respectively. Overall, 88.5% and 97.0% of bleeding episodes were controlled with 1 or ≤2 intervenous injections, respectively. Among subjects treated with FVIII prophylaxis prestudy (n = 79), 86% were dosed at least 3 times/week prestudy. Compared with prestudy dosing intervals, dosing intervals with rFVIIIFc were extended in 96.2% of subjects, were shortened in 2.5% of subjects, and were unchanged in 1.3% of subjects. The median (IQR) total weekly prophylactic consumption was comparable (prestudy FVIII: 78.0 [60.0, 102.0] IU/kg; on-study rFVIIIFc: 75.0 [70.0, 113.8] IU/kg). Conclusions: Longitudinal data from patients with severe hemophilia A treated with rFVIIIFc in A-LONG and ASPIRE confirm long-term safety, with no inhibitors observed in any subject. Low median ABRs were maintained, and rFVIIIFc demonstrated efficacy in the prevention and treatment of bleeding episodes. Prophylactic dosing intervals were extended, without an increase in median prophylactic factor consumption. 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 Pasi: Biogen: Consultancy, Honoraria; Genzyme: Consultancy, Honoraria; SOBI: Honoraria, Membership on an entity's Board of Directors or advisory committees; Octapharma: Consultancy, Honoraria, Research Funding; Pfizer: Consultancy, Honoraria. Perry:Novo Nordisk: Consultancy, Membership on an entity's Board of Directors or advisory committees; Biogen: Consultancy, Honoraria. Mahlangu:Bayer: Research Funding, Speakers Bureau; CSL: Consultancy, Research Funding, Speakers Bureau; Biotest: Speakers Bureau; Biogen: Consultancy, Research Funding, Speakers Bureau; Novo Nordisk: Consultancy, Research Funding, Speakers Bureau; Amgen: Speakers Bureau; Roche: Consultancy, Research Funding; Baxalta: Consultancy. Rangarajan:Baxter: Research Funding; Baxalta, now part of Shire: Other: Investigator Clinical Studies, Research Funding; Biogen: Consultancy; Biotest: Research Funding; Grifols: Consultancy, Research Funding; Pfizer: Research Funding; Novo Nordisk: Research Funding. Brown:Baxter: Consultancy; Biogen: Consultancy; Novo Nordisk: Consultancy. Hanabusa:Novo Nordisk: Honoraria, Membership on an entity's Board of Directors or advisory committees; Baxalta: Honoraria, Membership on an entity's Board of Directors or advisory committees; KaketsuKen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Pfizer: Honoraria; Bayer: Honoraria; Biogen: Honoraria, Membership on an entity's Board of Directors or advisory committees. Pabinger:Biotest: Honoraria, Membership on an entity's Board of Directors or advisory committees; CSL Behring: 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. Cristiano:Biogen: Employment, Equity Ownership. Tsao:Biogen: Employment, Equity Ownership. Winding:Sobi: Employment. Glazebrook:Biogen: Employment, Equity Ownership. Lethagen:Sobi: Employment. Jackson:Biogen: Consultancy, Research Funding; Pfizer: Research Funding; Bayer: Research Funding; Baxalta/Shire: Research Funding; Novo Nordisk: Research Funding; Baxter: Consultancy, Research Funding.


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