ALBERT

Description: A severely reduced ADAMTS13 activity due to inhibitory autoantibodies is a key feature of acquired thrombotic thrombocytopenic purpura (TTP), leading to the persistence of ultralarge VWF multimers, platelet aggregation and disturbance of microcirculation. We followed 39 patients (8 male, 31 female, mean age 38 years) with clinical signs of TTP over a period between 5 days to 16 years and observed a total of 53 episodes of TTP. ADAMTS13 was measured with a collagen-binding assay and the FRETS-VWF73 based Technozym ADAMTS-13 assay (activity and antigen, respectively). ADAMTS13 inhibitor was measured with a modified Bethesda method with both the above mentioned assays, and with the Technozym ADAMTS-13 INH ELISA. Thirty-one patients had autoimmune TTP, and 47 episodes of TTP were analyzed in these patients. In all acute episodes, ADAMTS13 activity was below the detection limit (0.2 U/ml in 66% of the episodes (after median 160 days). In the remaining cases anti-ADAMTS13 antibodies persisted during remissions for up to 2 years. In 3 cases the antibody reoccurred after initial normalization of ADAMTS13 activity, and clinical relapses followed. In total, 21 relapses were observed after a median of 46 months (range 1– 87), all associated with low ADAMTS13 levels. Rituximab was given in 7 cases of relapsing TTP and resulted in complete, durable clearance of the antibodies in 100%. Determination of ADAMTS13-related parameters is useful to distinguish between autoimmune, hereditary, and secondary forms of TTP and to choose an appropriate therapy. It is also useful to predict the risk of relapse in patients with TTP in remission.

Description: Background Protein C (PC) is a naturally occurring, vitamin-K dependent anticoagulant produced by the liver. Deficiency of PC, which can be congenital or acquired, results in a hypercoagulable state. Patients with severe PC deficiency may manifest severe, often life-threatening, disseminated intravascular coagulation (DIC), purpura fulminans (PF), and/or thromboembolism. Highly purified protein C concentrate prepared from human donor plasma (Ceprotin; Baxter Healthcare Corporation, Westlake Village, CA) is an approved therapy for prevention and treatment of venous thrombosis and PF in patients with severe congenital PC deficiency (SCPCD) in the United States. It is indicated in patients with SCPCD for PF and coumarin-induced skin necrosis, and short-term prophylaxis in the European Union and other countries. Use of protein C concentrate (human) has been reported in patients with acquired PC deficiency. The Ceprotin Treatment Registry is a prospective, international, multi-center, open-label, non-interventional, observational study designed to examine the long-term safety and effectiveness of protein C concentrate (human) in the clinical setting. This is the first large, real-world assessment of the treatment of a rare disease with protein C concentrate (human). Here we report data from the first interim analysis in June 2013 covering a 3-year enrollment period. Methods Patients of any age who received, or were initiating/receiving protein C concentrate are included. The study duration is 5 years (3-year enrollment period plus 2 years of follow-up). All study visits/assessments are in accordance with standard of care, with protein C concentrate dose, dose frequency, duration and route of administration determined by the investigator. The study objectives are to determine the most common medical diagnoses associated with protein C concentrate treatment, protein C concentrate treatment regimens, and safety information based on all serious adverse events (SAEs) and rate of treatment-related AE. Other objectives include: an examination of the relationship between protein C concentrate treatment and outcomes in all registry participants, as well as various subgroups. Descriptive statistical analyses are used. Results At the time of data extraction, 34 patients were enrolled from 26 centers; 10 centers in the United States and 16 centers in Europe. Half of the patients were males. The primary diagnosis of PC deficiency was congenital in 25 patients (73.5%) and acquired in 9 patients (26.5%). The median age at diagnosis was 0.03 years (range 0–19.9). Mean plasma PC activity level was 9% (range 1–40.0). The most common (in ≥3 patients) thrombotic disease-associated conditions were PF (50.0%); blindness (44.1%); thromboembolic disease (41.2%), which included deep vein thrombosis, arterial thrombosis and DIC; stroke (32.4%), and renal dysfunction (8.8%). Of the 23 patients being treated with protein C concentrate, 15 were administered protein C concentrate intravenously, and 8 patients received protein C concentrate subcutaneously. The body weights of patients receiving subcutaneous treatment ranged from 10.0 kg to 57.9 kg. A total of 15 patients received an anticoagulant treatment in addition to protein C concentrate. Eight patients reported 23 SAEs, all of which were considered not related to treatment. Eighteen (52.9%) patients reported 72 AEs; only 1 of them, an episode of upper respiratory infection, was considered possibly treatment-related. In 18 patients in whom PC activity recovery was determined after protein C concentrate treatment, there were no patients documented with poor recovery. Protein C concentrate was used during 18 surgeries/invasive procedures and considered effective in all interventions for which data were available. Conclusions Data from the first interim analysis of the Ceprotin Treatment Registry demonstrate that patients with both congenital and acquired severe PC deficiency who are treated with protein C concentrate (human) have a low incidence of treatment related SAEs and AEs, and treatment with protein C concentrate appears to be effective when used during surgery/invasive procedures. Further patient follow up will shed light onto clinical treatment outcomes. Disclosures: Manco-Johnson: CSL Behring: Membership on an entity’s Board of Directors or advisory committees, Research Funding; Novo Nordisk: Membership on an entity’s Board of Directors or advisory committees; Biogen Idec: Membership on an entity’s Board of Directors or advisory committees; Baxter BioScience: Membership on an entity’s Board of Directors or advisory committees; Bayer HealthCare: Membership on an entity’s Board of Directors or advisory committees, Research Funding; Eisai: Research Funding. Knoebl:Novo Nordisk: Consultancy, Honoraria; Baxter: Consultancy, Honoraria. Shapiro:Cangene: Research Funding; Biogen Idec: Research Funding; Baxter BioScience: Research Funding; Bayer HealthCare: Research Funding. Finnerty:Baxter: Employment, Equity Ownership. Yel:Baxter: Employment, Equity Ownership. Gelmont:Baxter: Employment, Equity Ownership.

Description: Introduction : Acquired thrombotic thrombocytopenic purpura (aTTP) is a rare, life-threatening thrombotic microangiopathy. A severe deficiency in ADAMTS13 activity caused by inhibitory autoantibodies leads to accumulation of ultra large von Willebrand factor (ULvWF) multimers and formation of microthrombi in small blood vessels with associated thrombocytopenia, hemolytic anemia, tissue ischemia and organ dysfunction (e.g., brain, heart, and kidneys). Caplacizumab directly blocks the interaction of the vWF A1 domain with the GPIb platelet receptor and prevents formation of microthrombi. The key efficacy and safety results of the double-blind (DB), placebo-controlled, phase 3 HERCULES study of caplacizumab for the treatment of aTTP were reported previously (Scully et al., Blood 2017 130:LBA-1). Herein, we present the results of a post-hoc analysis of the safety results normalized to time of exposure during the DB treatment period. Methods : Patients with an acute episode of aTTP who had received one plasma exchange (PE) treatment were randomized 1:1 to placebo or 10 mg caplacizumab, in addition to daily PE and corticosteroids. A single IV dose of study drug was given before the first on-study PE and a SC dose was given daily during the PE period and 30 days thereafter. If at the end of this period there was evidence of ongoing disease, such as suppressed ADAMTS13 activity, investigators were encouraged to extend the blinded treatment for a maximum of 4 weeks together with optimization of immunosuppression. All patients entered a 28-day treatment-free follow up period after the last dose of study drug. In case of a recurrence during the DB treatment period, patients were switched to open-label (OL) caplacizumab, together with re-initiation of daily PE and immunosuppression, while maintaining the blind for the initial treatment allocation. Analysis of treatment-emergent adverse events (TEAEs) was performed on the study's safety population (i.e., all patients who received at least 1 administration of study drug). To control for differences in time of exposure, incidence rates (IR) per 100 patients months were calculated as 100 x number of events / (total number of months observed within analysis period, summed for all patients in the treatment group). Results : The safety population consisted of 71 caplacizumab-treated and 73 placebo-treated patients. 31 patients experienced an exacerbation during the DB period, 28 in the placebo group and 3 in the caplacizumab group; 28 of them were switched to OL treatment with caplacizumab (26 of the 28 placebo-treated patients and 2 of the 3 caplacizumab-treated patients). As a consequence, the median (min; max) duration of study drug treatment during the DB treatment period, was 35 (1; 65) days for the DB caplacizumab group and 23 (2; 66) days for the DB placebo group. During the overall study period, at least one TEAE was reported in 69 patients (97.2%) in the caplacizumab group and 71 patients (97.3%) in the placebo group; the most frequent (occurring in 〉10% of patients in at least one of the treatment groups) TEAEs are presented in Table 1. After normalization for the time of exposure, the IR of any TEAE was lower in the caplacizumab group (535.6) vs. placebo group (821.7). TEAEs with a higher IR (≥5/100 patients months difference) in the caplacizumab group vs. placebo were epistaxis (39.1 vs. 3.3) and gingival bleeding (14.9 vs 1.7); TEAEs with a higher IR in the placebo group vs. caplacizumab were TTP (48.3 vs. 3.4), hypokalemia (25.0 vs 5.7), contusion (40.0 vs 8.0), rash (16.7 vs 5.7), insomnia (13.3 vs 8.0) and hypertension (13.4 vs 4.6). The IR of any SAE was 26.4 in the caplacizumab group and 83.3 in the placebo group. There were no SAEs with a higher IR (≥5/100 patients months difference) in the caplacizumab group compared to placebo. SAEs with an IR higher in the placebo group vs. caplacizumab were TTP (48.3 vs. 3.4) and anaphylactic transfusion reaction (5.0 vs. 0). Conclusions : After normalization to time of exposure, TEAEs occuring more frequently in the caplacizumab group were epistaxis and gingival bleeding, while TTP, hypokalemia, contusion, rash, imsomnia and hypertension occurred more frequently in the placebo group. This post-hoc analysis confirms the overall good tolerability of caplacizumab for the treatment of aTTP with mucocutaneous bleeding being the most relevant risk, consistent with the mechanism of action of this drug. Disclosures Kremer Hovinga: Shire: Other: Member of Advisory Board, Research Funding; Ablynx: Other: Member of Advisory Board. Scully:Novartis: Honoraria, Other: Member of Advisory Board, Speakers Bureau. Cataland:Alexion: Research Funding; Shire: Consultancy; Ablynx: Consultancy, Other: Member of Advisory Board. Peyvandi:Ablynx: Other: Member of Advisory Board, Speakers Bureau; Ablynx: Other: Member of Advisory Board, Speakers Bureau; Novo Nordisk: Speakers Bureau; Novo Nordisk: Speakers Bureau; Roche: Speakers Bureau; Roche: Speakers Bureau; Ablynx: Other: Member of Advisory Board, Speakers Bureau; Sobi: Speakers Bureau; Sobi: Speakers Bureau; Shire: Speakers Bureau; Novo Nordisk: Speakers Bureau; Octapharma US: Honoraria; Shire: Speakers Bureau; Ablynx: Other: Member of Advisory Board, Speakers Bureau; Octapharma US: Honoraria; Novo Nordisk: Speakers Bureau; Kedrion: Consultancy; Kedrion: Consultancy; Grifols: Speakers Bureau; Octapharma US: Honoraria; Shire: Speakers Bureau; Shire: Speakers Bureau; Grifols: Speakers Bureau; Roche: Speakers Bureau; Grifols: Speakers Bureau; Novo Nordisk: Speakers Bureau; Roche: Speakers Bureau; Kedrion: Consultancy; Kedrion: Consultancy; Shire: Speakers Bureau; Kedrion: Consultancy; Grifols: Speakers Bureau; Sobi: Speakers Bureau; Octapharma US: Honoraria; Octapharma US: Honoraria; Sobi: Speakers Bureau; Sobi: Speakers Bureau; Roche: Speakers Bureau; Grifols: Speakers Bureau; Ablynx: Other: Member of Advisory Board, Speakers Bureau. Coppo:Ablynx: Consultancy. Knöbl:Ablynx: Consultancy, Other: Member of Advisory Board. De La Rubia:Ablynx: Consultancy, Other: Member of Advisory Board. Minkue:Ablynx: Employment. Sousa:Ablynx: Employment. Callewaert:Ablynx: Employment. De Winter:Ablynx: Employment. Metjian:Ablynx: Other: Member of Advisory Board.

Description: Key Points A new technology is presented to assess apparent affinities of FVIII-specific antibodies, differentiated for isotypes and IgG subclasses. Affinities of FVIII-specific antibodies in patients with FVIII inhibitors are up to 100-fold higher than in patients without inhibitors.

Description: Acquired hemophilia A is a rare bleeding disorder caused by autoantibodies to coagulation FVIII. Bleeding episodes at presentation are spontaneous and severe in most cases. Optimal hemostatic therapy is controversial, and available data are from observational and retrospective studies only. The EACH2 registry, a multicenter, pan-European, Web-based database, reports current patient management. The aim was to assess the control of first bleeding episodes treated with a bypassing agent (rFVIIa or aPCC), FVIII, or DDAVP among 501 registered patients. Of 482 patients with one or more bleeding episodes, 144 (30%) received no treatment for bleeding; 31 were treated with symptomatic therapy only. Among 307 patients treated with a first-line hemostatic agent, 174 (56.7%) received rFVIIa, 63 (20.5%) aPCC, 56 (18.2%) FVIII, and 14 (4.6%) DDAVP. Bleeding was controlled in 269 of 338 (79.6%) patients treated with a first-line hemostatic agent or ancillary therapy alone. Propensity score matching was applied to allow unbiased comparison between treatment groups. Bleeding control was significantly higher in patients treated with bypassing agents versus FVIII/DDAVP (93.3% vs 68.3%; P = .003). Bleeding control was similar between rFVIIa and aPCC (93.0%; P = 1). Thrombotic events were reported in 3.6% of treated patients with a similar incidence between rFVIIa (2.9%) and aPCC (4.8%).

Description: Background: The investigational anti von Willebrand Factor (vWF) aptamer ARC1779 effectively inhibits vWF activity in blood samples of controls and of patients suffering from thrombotic thrombocytopenic purpura (TTP) (Jilma et al, Blood2007;110:279a, Gilbert et al. Circulation2007;116:2678–2686). Methods: A 39 year old comatose male patient with acute (TTP) was treated with daily plasma exchange. Further, the patient received rituximab (375mg/m2 first treatment on day 8, and weekly thereafter for 8 weeks) and was splenectomized on day 18. Due to the refractory nature of his TTP, the patient received a concomitant intravenous infusion of ARC1779 at a rate of 2 μg/kg/min beginning on day 30. Results: ARC1779 increased the platelet count slightly from 7 to a maximum of 30/nL; during this period septicaemia and DIC may have blunted the rise in platelet counts. However, platelet counts dropped to 5/nL by 16h after cessation of infusion (day 34). The infusion of ARC1779 was re-started on day 37, and platelet counts increased from 9 to 45/nL. (Figure) Due to a temporary lack of drug, the dose of ARC1779 was stopped at 78h, and platelet counts fell to 12/nL by 12 h after interruption of the infusion. (circle in the Figure) When ARC1779 was re-started, platelet counts increased to a maximum of 97/nL and the patient’s neurologic status improved to near normal under therapy with ARC1779 over the next week. Conclusions: ARC1779 was well-tolerated, and caused a reproducible rise in platelet counts, which alleviated severe thrombocytopenia, in an otherwise refractory TTP case. This effect was reproducible under serial “re-challenge”. Together with the observed improvement in neurologic function, the data provide clinical proof-of-concept and suggest that ARC1779 treatment might improve the organ dysfunction which typically occurs in acute TTP. These data provide a rational basis for ongoing and planned phase II trials of ARC1779. Figure Figure

Description: Purpura fulminans (PF) is rapidly progressing, life-threatening disorder, characterized by skin lesions with a typical morphology, disseminated intravascular coagulopathy, multiple organ failure, septic shock, most often, but not exclusively caused by infections (meningococci, pneumococci, and others). It is associated with a breakdown of the protein C system, an important regulator of blood coagulation, leading to consumption coagulopathy, intravascular fibrin deposition, downregulated fibrinolysis, disturbance of microcirculation and finally death from multiple organ failure. Mortality of severe sepsis with coagulopathy is as high as 80-100%, and persistent disabilities (i.e. amputations) are frequent in survivors. Several case series including more than 340 patients, suggest that substitution of protein C zymogen can impressively improve coagulopathy, reduce amputation rate and improve survival compared to historical controls in PF associated with sepsis in neonates, children and adults, encouraging some centers to incorporate it in their local guidelines for treatment of purpura fulminans. We report a series of 9 consecutive patients with purpura fulminans, treated with a plasma-derived protein C zymogen concentrate (Ceprotin®, Baxter, Vienna, Austria) for acute onset PF in 3 Vienna hospitals, in which the treatment guidelines included protein C replacement. Median age was 29 years (range 2 months to 73 years), 5 male, 4 female, 5 adult, 4 pediatric patients were treated, respectively. Six patients had meningococcal sepsis, 2 had overwhelming post-splenectomy infections, and 1 had heat-shock induced coagulopathy. All patients presented with typical skin lesions and acute critical illness and were admitted to intensive care units. Coagulopathy was present in 100%, severe vasopressor-dependent sepsis in 100%, acute renal failure in 89%, respiratory failure in 89%. Median SAPS II score in the adults was 78 (range 45-97), predicting a mortality of 78.3% (range 31-88.5%). All pediatric patients had a Glasgow Meningococcal Septicemia prognostic score 〉8, indicating a fatal outcome. Renal replacement therapy was necessary in 56%, mechanical ventilation in 89%. Initial protein C levels were markedly decreased in the 8 patients with infections. Standardized sepsis therapy was applied according to the surviving sepsis guidelines. Protein C was given as an initial bolus infusion (100 U/kg) followed by a continuous infusion with 10 U/kg/h, adjusted to obtain plasma protein C activity levels of 1.0 U/mL. In addition, platelet, red blood cell, fibrinogen and antithrombin concentrates were given as needed. In one patient (PF caused by heat shock) protein C infusion was stopped after 2 days, and he died after 10 days from refractory multiple organ failure. All other patients (with infection-induced PF) survived. Coagulopathy resolved within a few days, and all patients could successfully be weaned from intensive care therapy. Organ function was completely restored without residual dysfunction. One patient needed amputation of both forefeet and nose reconstruction, 6 patients had, in part extended, scar formation at the skin. Median follow up was 8 months (range 2-20). At that time all patients were fully active without apparent limitations. In conclusion, standardized, full-code sepsis therapy, together with protein C substitution, resulted in very high survival rate of patients with infection-induced PF (as compared to predicted mortality) and a low rate of disabilities in this otherwise deleterious disease. As Ceprotin® is approved only for congenital protein C deficiency, controlled clinical studies are urgently needed to gain more scientific evidence for this potentially life-saving, but still off-label therapy in patients with PF. Disclosures: Knoebl: Novo Nordisk: Consultancy, Honoraria; Baxter: Consultancy, Honoraria. Off Label Use: plasma derived protein C concentrate (Ceprotin(R)) for acquired protein C deficiency in purpura fulminans.

Description: Background:Chronic myelomonocytic leukemia (CMML) is a hematopoietic malignancy of the elderly with a heterogenous molecular pathophysiology. Whereas mutations in components of the RAS pathways are among the most common somatic mutations in CMML the JAK2 V617F mutation which is a typical finding in polycythemia vera and around 50% of patients with essential thrombocythemia and primary myelofibrosis, respectively, is by far less frequently detected in CMML but can be consistently found in a subgroup of patients in larger series. Due to the fact that JAK2 V617F-positive CMML is a rare disease the clinical, hematological and in vitro growth characteristics of this entity are poorly investigated. In the "Austrian Biodatabase for Chronic Myelomonocytic Leukemia (ABCMML)" we retrospectively and prospectively collect clinical, biologic, and molecular information of patients with CMML from different centers in a real life setting. Aims:Our aim was to characterize the clinical, hematological, molecular and biologic features of CMML patients harboring a JAK2 V617F mutation. Methods:The diagnosis of CMML was established according to diagnostic criteria of the World Health Organization (WHO) classification of 2008 (Vardiman et al, Blood 2009). Clinical and hematological data were obtained from patients records. For molecular characterization we used next-generation sequencing with amplicon-based target enrichment of 39 CMML associated genes. Only mutations with an allele burden of 〉10% were considered positive in this analysis. Autonomous colony-forming units granulocyte/macrophage (CFU-GM) growth in the absence of exogenous cytokines was assessed using semisolid cultures as previously described (Geissler et al, J Exp Med 1996). Results:Up to now targeted NGS data are available in 116 patients and in vitro culture data in 75 patients respectively. We identified 13 CMML patients who had a JAK2 V617F mutation with an allele frequency 〉10%. Clinical, hematological, and biologic characteristics in these patients were compared with 103 patients who had NGS sequencing and were negative for the JAK2 V617F mutation. As shown in Table 1 JAK2 V617F-positive CMML patients had significantly higher WBC counts, higher hemoglobin values, higher platelet counts and more pronounced splenomegaly as compared to JAK2 V617F-negative patients. On the other hand the percentage on monocytes in peripheral blood and the numbers of CFU-GM growing in vitro without addition of exogenous growth factors were lower in CMML patients with the JAK2 V617F mutation as compared to patients without this mutation. The majority of JAK2 V617F-positive patients had additional mutations that can be also found in JAK2 V617F-negative patients, in particular mutations in genes of epigenetic regulation and RNA-splicing, respectively. As shown in Figure 1 there was a trend towards a better survival of patients with the JAK2 V617F mutation as compared to JAK2 V617F-negative patients (p=0.05). In a JAK2 V617F-positive CMML patient with splenomegaly, who was treated with the JAK1/2 inhibitor ruxolitinib off label, we were able to demonstrate the disappearance of constitutional symptoms and a durable spleen response lasting for over 56 months (Fig. 2). Conclusion:Out data show that CMML patients with the JAK2 V617F mutation have hematological, biologic and clinical characteristics different from JAK2 V617F-negative CMML patients. These findings suggest that JAK2 V617F-positive CMML patients should be regarded as a distinct subgroup which may benefit from specific targeted treatments. Disclosures Geissler: Novartis: Honoraria. Pfeilstöcker:Novartis: Consultancy, Speakers Bureau. Burgstaller:Novartis: Consultancy, Honoraria. Zach:Novartis: Other: Honoraria for Advisory Board. Hörmann:Novartis: Other: Honoraria for Advisory Board. Jäger:Roche: Other: Personal fees, Research Funding. Sperr:Amgen: Honoraria, Research Funding; Novartis: Honoraria. Kusec:Novartis: Other: Honoraria for lectures. Valent:Novartis: Honoraria, Research Funding; Amgen: Honoraria; Celegene: Honoraria, Research Funding.