Eculizumab Therapy Research Articles

Real-World Use of Therapeutic Anticoagulation in Patients with Paroxysmal Nocturnal Hemoglobinuria. Results of a Survey of Physicians in Australia

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare and life-threatening hematopoietic stem cell disorder characterized by uncontrolled complement-mediated hemolysis. Patients with PNH are at increased risk of thromboembolism and premature death. This risk is predominantly due to the effects of chronic hemolysis and platelet activation. Eculizumab, a monoclonal antibody that inhibits terminal complement activation, has been shown to reduce hemolysis and dramatically reduce the rate of thromboembolism. A previous publication (Kelly et al, 2011) suggested that cessation of therapeutic anticoagulation (TAC) in PNH patients on eculizumab with no prior history of thrombosis is safe. There are very few reports on the outcomes of cessation of TAC in PNH patients on eculizumab who have a prior history of thrombosis or on the use of non-vitamin K antagonist oral anticoagulant (NOAC) agents in PNH patients with a history of thrombosis.In Australia, patients with PNH are predominantly managed by individual hematologists rather than at a single centre and hence anticoagulation practices following the introduction of eculizumab therapy are variable. We surveyed Australian hematologists managing eculizumab-treated patients with PNH to obtain the details of anticoagulation management and incidence of thrombotic events in their patients.We received responses from 30 hematologists caring for a total of 58 patients with PNH on eculizumab (1-17 patients per hematologist) and the table summarises the results. TAC as primary prophylaxis had been ceased in 10 patients with no recurrent thrombotic events. One (1) patient remains on primary prophylaxis due to persistently high D-dimer and factor VIII levels. TAC for secondary prophylaxis had been ceased in 2 patients due to bleeding (1 patient with subdural hematoma, 1 patient with gastrointestinal bleeding) and neither of these patients had a further thrombotic event. One patient, with a prior history of thrombosis, requested cessation of TAC and subsequently developed a provoked thrombosis.Three patients not receiving TAC when eculizumab was commenced developed thrombosis; two (2) patients had provoked deep venous thromboses and one patient developed a splanchnic vein thrombosis following a cholecystectomy in association with severe sepsis.One patient had a portal vein thrombosis immediately prior to commencing eculizumab therapy but has never received TAC due to severe coexistent thrombocytopenia from myelodysplasia. This patient has not had a recurrent thrombosis.Three (3) patients with thrombotic events prior to eculizumab therapy (1 patient with pulmonary emboli, 1 patient with cerebral venous sinus thrombosis and 1 patient with inferior vena cava thrombosis) had anticoagulant therapy changed from warfarin to rivaroxaban. At a follow-up of at least twelve months for all 3 patients there have been no recurrent thrombotic events and no bleeding complications.In conclusion, these Australian data are consistent with those reported by Kelly suggesting that cessation of primary prophylaxis in PNH patients on eculizumab is safe. Cessation of TAC in PNH patients on eculizumab with a prior thrombosis can be considered if there are clear contraindications to anticoagulation. Thromboprophylaxis in situations of increased risk of venous thromboembolism remains essential for all PNH patients not on TAC, even when they are on eculizumab therapy. The three patients on rivaroxaban as secondary prophylaxis are, to our knowledge, the first reported patients with PNH treated on a NOAC.TableNumber of patientsNew thrombotic eventsEculizumab treated58Ceased TAC: Total1. As 1o prophylaxis2. As 2o prophylaxis(i) Due to bleeding(ii) At patient request1410431-None-None1 (provoked)TE in patients not on TAC at commencement of eculizumab33 (provoked)NOAC as 2o prophylaxis3None DisclosuresSzer:Alexion: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Alexion: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Amgen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Alexion Australia: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Amgen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Pfizer: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Pfizer: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Shire: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Shire: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Forsyth:Alexion: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Giese:Alexion: Employment.

Circulating Endothelial Progenitor Cells and Their Relation to Thrombosis in Paroxysmal Nocturnal Hemoglobinuria

Introduction: Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired clonal hematopoietic stem cell disorder. Chronic intravascular hemolytic anemia, bone marrow failure and thrombophilia are the main clinical findings. Thrombosis is one of the most important cause of morbidity and mortality of this disease. Multiple factors are held responsible for thrombotic tendency in these patients. Endothelial progenitor cells (EPCs) originate from primitive hematopoietic stem cells and are able to turn into endothelial cells. There are extremely small numbers of EPCs in the circulation under normal conditions. The level of EPCs is considered to be indicative of restoration capacity in case of vascular disease and potential damage. Lower EPC levels are also considered as a risk factor in cardiovascular diseases. In this study, our aim was to investigate circulating EPCs in PNH and their relationship with thrombosis. Seventeen patients with PNH, 18 patients with aplastic anemia and 10 healthy volunteers were included in the study. CD309, CD133 and CD34 antibodies were used in order to determine circulating EPCs by flow cytometry and cells which expressed all three antibodies were analyzed as EPC. Prepared samples were read using a prepared list mode software for endothelial progenitor cells on FACS Diva software in BD FACS Canto II device with 6 color lasers and a total of 1,000,000 cells per analysis were evaluated. EPC levels were compared between untreated PNH patients and who were on eculizumab therapy. Statistical analysis was performed using SPSS 22.0 software. The distribution of variables was evaluated by Kolmogorov-Smirnov test, the analysis of quantitative data was evaluated by ANOVA, Kruskal-Wallis, Mann-Whitney U tests and the analysis of the qualitative data was evaluated by chi-square test.Findings and Discussion: The thrombotic complications were observed in five PNH patients. All of these patients had a history of portal vein thrombosis. One of them also had a history of peripheral arterial disease and amputation related to this. There was not a significant difference in EPC levels between patients with and without a history of thrombosis (p>0,05). We also did not find any significant difference between levels of EPC's in PNH groups with or without eculizumab therapy (p˃0,05). There was no significant difference in levels of EPC between aplastic anemia and PNH groups (p ˃ 0,05). However, we found a significant positive correlation between the levels of EPC and LDH in multivariate analysis (p < 0,05). This finding suggests that hemolysis causes vascular endothelium and promotes new blood vessel formations. Increased EPCs in PNH might be an indirect indicator for vascular endothelium damage in PNH.TableGeneral Features and Rates of EPC of PNH, AA, Healthy Volunteers GroupsAplastic Anemia groupPNH groupControl grouppAgemean±s.smedian (min-max)40.0±14.7 37.5 (20.0-67.0)41.9±13.9 43.0 (19.0-78.0)29.3±3.5 29.5(24.0-34.0)0.047SexFemale n-% Male n-%7 38,9% 11 61.1%9 52.9% 8 47.1%5 50% 5 50%0.687EPC(%)mean±s.s median (min-max)0.2% 0.2% 0.1% (0.0-0.6%)0.3%±0.3% 0.1% (0.0-0.9%)0.1%±0.0% %0,0(%0,0-0,2)0.393All Events (x1000)mean±s.s median (min-max)617±172* 565 (360-914)588±255* 471 (250-1000)878±143 950(655-1000)0.003CD309 and CD34mean±s.s median (min-max)0.003±0.002 0.002 (0.001-0.007)0.005±0.004 0.000-0.011)0.001±0.001 0.001 (0.000-0.002)0.009CD133mean±s.s median (min-max)45.8±36.3 58.3 (0.0-88.2)45.8±39.6 60 (0.0-94.7)42.0±19.4 46.4 (11.1-81.3)0.867ANOVA / Kruskal-Wallis / Mann-Whitney U test / Chi-square test*The difference with the control group, p <0.05EPCs: Endothelial progenitor cells DisclosuresYenerel:Alexion: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau.

Complement Inhibition with Eculizumab in Patients with Cold Agglutinin Disease (CAD): Results from a Prospective Phase II Trial (DECADE Trial)

▪BACKGROUND: Cold agglutinin disease (CAD) is a rare autoimmune hemolytic anemia characterized by hemagglutination and complement-mediated extra- and intravascular hemolysis. Conventional therapeutic approaches, such as corticosteroids, intravenous immunoglobulin G, alkylating agents or other immunosuppressive drugs, are largely ineffective, and the therapeutic efficacy of rituximab is limited. Successful treatment of a patient with CAD with the terminal complement inhibitor eculizumab reported by us previously (Röth et al., Blood 2009) prompted us to test this novel approach in a larger number of patients.PATIENTS and METHODS: We conducted a prospective, controlled, non-randomized, multicenter phase II trial with pre- and post-treatment comparison. Inclusion criteria were symptomatic cold agglutinin-mediated hemolysis with a serum lactate dehydrogenase (LDH) level ≥ 2 x upper limit of normal and a cold agglutinin titer > 64 at 4°C. Eculizumab was given by intravenous infusion at 600 mg weekly for 4 weeks, followed 1 week later by a 900 mg dose and then 900 mg every other week through week 26. Two weeks before the first dose patients received vaccination against N. meningitidis. The primary endpoint was LDH level, secondary endpoints included transfusion requirements, parameters of intravascular hemolysis, quality of life, 6-minute walk test (6MWT), circulatory symptoms and thrombosis. The analysis was performed in the intent-to-treat population. Missing data were replaced by carrying the last observation forward. The trial was registered at http://clinicaltrials.gov as NCT01303952.RESULTS: Between 2011 and 2014 13 treatment-naïve or pretreated patients with CAD were enrolled. The median age was 74 years (range: 64 - 80), with a male-to-female ratio of 3 to 10. After treatment with eculizumab the LDH decreased from a median pre-treatment level of 572 U/L (mean ± standard deviation: 670 ± 300 U/L) by an average of 56% to a median end-of-treatment level of 327 U/L (400 ± 279 U/L; p = 0.0215, Wilcoxon signed-rank test). This was accompanied by a reduction in transfusion requirement from a median of 4.0 red blood cell units per patient in the 12-month period preceding participation in the study to 0.0 units during treatment with eculizumab. In 9 patients, transfusion requirements decreased during eculizumab therapy, in 3 patients, transfusions were required neither before nor during the study, and in one patient, transfusion requirement deteriorated (p = 0.0215, Exact McNemar's test). The result of the 6MWT improved from a median of 358 m at baseline to a median of 420 m at the end of treatment (p = 0.078). Questionnaires for quality of life showed no significant changes. During the enrollment phase, 7 thromboembolic events including 1 pulmonary embolism were recorded in a total of 4 patients; by contrast, no thromboembolic events were observed during treatment with eculizumab. A total of 37 adverse events were reported of which one was considered as probably related to eculizumab (pneumonia, patient recovered). All in all, 57% of adverse events were classified as unrelated, 5% as unlikely to be related, 32% as possibly related, and 3% as probably related to treatment. There were 4 serious adverse events.CONCLUSIONS: Treatment with eculizumab was safe and well tolerated in patients with CAD. It resulted in a statistically significant reduction in hemolysis and transfusion requirements and appeared to have a favorable impact on thromboembolic complications. The results of this trial support the notion that terminal complement activation is a relevant mediator of erythrocyte destruction in CAD. DisclosuresRöth:Alexion Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Geron: Research Funding. Off Label Use: Use of eculizumab in CAD. Bommer:Alexion Pharmaceuticals: Honoraria. Hüttmann:Celgene: Other: Travel support, Speakers Bureau; Takeda: Consultancy, Other: Travel support; Gilead: Consultancy; Amgen: Consultancy, Research Funding; Roche: Research Funding. Schrezenmeier:Alexion Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Dührsen:Amgen: Honoraria, Research Funding; Roche: Honoraria, Research Funding; Alexion Pharmaceuticals: Honoraria, Research Funding.

Eculizumab Prevents Thrombotic Microangiopathy: Long-Term Follow-up Study of Patients with Atypical Hemolytic Uremic Syndrome

▪Background: Eculizumab was demonstrated to effectively treat and prevent thrombotic microangiopathy (TMA) and to improve renal function and hematologic parameters for up to 2 years in4 previous prospective clinical trials and in 1 retrospective study of patients with atypical hemolytic uremic syndrome (aHUS). Patients in these studies enrolled in a long-term follow-up study, in which rates of TMA were evaluated during eculizumab treatment and during discontinuation from eculizumab.Methods: Data were gathered from an ongoing, observational, multicenter study of aHUS patients treated with eculizumab in 5 prior clinical studies. The primary endpoint was TMA event rate post-parent study during on-treatment (ON; among patients receiving eculizumab) and off-treatment (OFF; among patients who discontinued eculizumab) periods.Results: As of March 28, 2015, 87 patients, including 35 children <18 years of age (40%) and 52 adults ≥18 years of age (60%), enrolled in the study (Table). Of these, 76 patients had ON and 39 patients had OFF treatment periods with median follow-up of 26.1 and 20.1 months, respectively. A reduced dosage of eculizumab was received by 33 of 87 patients (38%). Seventeen of 39 patients (44%) reinitiated eculizumab after therapy discontinuation. The TMA event rates were 7.3 and 19.9 per 100 patient-years for ON and OFF patients, respectively. The rate of TMA in ON patients was greater in those receiving reduced dosing compared with label recommendations (Table). OFF patients had higher estimated glomerular filtration rates at time of discontinuation than ON patients. Age, frequencies of higher-risk complement factor mutations (CFH, C3, or CFB) and kidney transplant status were not different between ON and OFF patients. Factors that independently predicted TMA events included: ON treatment status (compared with OFF; hazard ratio [HR], 0.19; 95% confidence interval [CI], 0.07‒0.49; P<0.001), higher-risk mutations (compared with no mutation; HR, 5.51; 95% CI, 1.61‒18.84; P =0.007), and lower-risk mutations (compared with no mutation; HR, 3.70; 95% CI, 1.05‒13.02; P =0.04).Conclusions: The TMA event rate was 2.7-fold higher after eculizumab discontinuation compared with patients receiving ongoing eculizumab therapy. TMA event rates were lowest during on-label dosing, higher during reduced dosing, and highest during off-treatment periods. These findings suggest that patients with aHUS have a progressive increase in the risk of TMA events during periods of reduced dosing and after discontinuation of eculizumab, compared with on-label eculizumab dosing. [Display omitted] DisclosuresGreenbaum:Alexion Pharmaceuticals: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Fakhouri:Alexion Pharmaceuticals: Consultancy. Kincaid:Alexion Pharmaceuticals: Employment, Equity Ownership. Licht:Alexion Pharmaceuticals: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Achillon: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Mix:Alexion Pharmaceuticals: Employment, Equity Ownership. Provôt:Alexion Pharmaceuticals: Honoraria. Rondeau:Alexion Pharmaceuticals: Consultancy, Membership on an entity's Board of Directors or advisory committees. Sheerin:Alexion Pharmaceuticals: Honoraria. Wang:Alexion Pharmaceuticals: Employment, Equity Ownership. Menne:Alexion Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees.

Clinical Benefit of Eculizumab in Patients with No Transfusion History in the International Paroxysmal Nocturnal Hemoglobinuria Registry

▪Introduction: Studies in patients with paroxysmal nocturnal hemoglobinuria (PNH) have shown that eculizumab reduces intravascular hemolysis, improves disease symptoms, and increases life expectancy. The objective of this analysis was to characterize, in a real-world setting, the benefit of eculizumab therapy in patients with PNH with no history of red blood cell (RBC) transfusion, with a special focus on high disease activity (HDA).Methods: The International PNH Registry is a prospective, observational study of patients with a PNH clone of 0.01-100%. Three patient populations were studied: 1) non-transfused untreated patients, 2) non-transfused eculizumab-treated patients, 3) eculizumab-treated patients who received ≥1 RBC transfusions in the 6 months prior to initiation of eculizumab. Transfused treated patients served as an additional comparison group. The primary outcome, assessed using multivariate linear regression, was mean absolute change from baseline to 6 months in LDH (U/L) in non-transfused treated and non-transfused untreated patients. Secondary outcomes were mean changes in patient-reported FACIT-Fatigue and EORTC-QLQ-C30 Fatigue scores from baseline to last available assessment.Results: A total of 1,547 patients were enrolled on or before April 30, 2012. The total study population (N=294) consisted of 1) 144 non-transfused untreated patients, 2) 45 non-transfused eculizumab-treated patients, and 3) 105 transfused eculizumab-treated patients. Of these, 136/144, 43/45, and 99/105 had HDA, respectively (Figure). At baseline, non-transfused untreated patients had the highest mean hemoglobin and lowest clone size (Table 1). Mean absolute reticulocytes were highest in the transfused treated group. Non-transfused untreated patients had the least mean absolute change in LDH from baseline to 6 months (-39.4 U/L) compared to non-transfused treated patients (-1318.8 U/L) and transfused treated patients (-1722.2 U/L) (Table 2). Non-transfused treated patients had a clinically meaningful mean percentage change in LDH compared with untreated patients (-69.9% versus -1.6%; p<0.001 in multivariate linear regression model evaluating absolute change). Statistically significant and clinically meaningful improvements in FACIT-Fatigue scores (increase by ≥4 points) were seen in 73.7% of non-transfused treated patients vs. 24.6% of untreated patients; for EORTC-Fatigue (decrease ≥10 points) in 84.2% vs. 33.3%, respectively. Similarly, non-transfused treated patients with HDA (n=43) had significantly reduced LDH levels (p<0.001) and clinically meaningful improvements in FACIT-Fatigue (p=0.004) and EORTC (p=0.02) compared with untreated patients (n=136).Conclusions: Data from the International PNH Registry demonstrate that patients with PNH carry a heavy disease burden. Findings show statistically significant and clinically meaningful differences in LDH reduction and improvement in fatigue in patients treated with eculizumab, irrespective of transfusion history, and in patients with HDA.Table 1Baseline Patient Clinical CharacteristicsNon-transfusedTransfusedUntreated(N=144)Eculizumab Treated(N=45)Eculizumab Treated(N=105)Hemoglobin (g/L)Mean (SD)114.1 (24.0)103.3 (20.6)101.3 (88.2)Absolute reticulocytes (x109 /L)Mean (SD)128.7 (95.02)124.4 (68.9)157.4 (79.0)%GPI-deficient granulocytesMean (SD)61.7 (28.0)68.0 (24.2)82.1 (18.4)History of TE, n (%)16 (11.1)13 (28.9)23 (21.9)GPI, glycosylphosphatidylinositol; RBC, red blood cell; SD, standard deviation; TE, thrombotic eventTable 2Change in LDH and FACIT-Fatigue and EORTC ScoresNon-transfusedTransfusedUntreated(N=144)Eculizumab Treated(N=45)Eculizumab Treated(N=105)LDH, U/LMean (SD) change from baseline to 6 months-39.4 (357.5)-1318.8 (1065.3)-1722.2 (1152.7)FACIT-FatigueAbsolute change nMean (SD) change from baseline to last available assessment69 0.1 (9.6)19 10.5 (11.6)*29 5.5 (12.3)Clinically meaningful improvement, % (n)24.6 (17)73.7 (14)55.2 (16)EORTC-FatigueAbsolute change n Mean (SD) change from baseline to last available assessment69 −1.5 (26.9)19 −22.8 (22.1)†30 -11.9 (29.3)Clinically meaningful improvement, % (n)33.3 (23)84.2 (16)46.7 (14)LDH, lactate dehydrogenase; SD, standard deviation*p<0.01 vs. untreated group and †p<0.05 vs. untreated group in multivariable models [Display omitted] DisclosuresAlmeida:Celgene: Consultancy; Novartis: Consultancy; Bristol Meyer Squibb: Speakers Bureau; Shire: Speakers Bureau. Bedrosian:Alexion Pharmaceutials: Employment, Equity Ownership, Patents & Royalties. Cole:Alexion Pharmaceuticals: Employment, Equity Ownership. Muus:Alexion Pharmaceuticals: Honoraria. Schrezenmeier:Alexion Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Szer:Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Shire Australia: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Pfizer Australia: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Alexion Pharmaceuticals Australasia Pty Ltd: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sanofi: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Rosse:Alexion Pharmaceuticals: Consultancy.

Complement Genotype and Multiparametric Laboratory Analysis to Predict Response to Eculizumab and to Adjust Treatment in Patients with Paroxysmal Nocturnal Hemoglobinuria

▪Background: Paroxysmal Nocturnal Hemoglobinuria (PNH) is a disorder caused by the proliferation of hematopoietic stem cells carrying a somatic mutation in the gene PIG-A, which is necessary for the biosynthesis of the glycosyl phosphatidyl-inositol anchor. As a consequence, PNH erythrocytes lack, among other proteins, the complement regulators CD55 and CD59 and become susceptible to complement-mediated intravascular hemolysis. Before Eculizumab, a monoclonal antibody that prevents C5 cleavage, life expectancy of PNH patients was about 10-15 years from diagnosis, being thrombotic events the main cause of death. Despite the unquestionable success of Eculizumab therapy to treat PNH, the responses among PNH patients show heterogeneity, with some patients remaining transfusion-dependent for reasons not completely understood.Methods: To get further insight into the different responses to Eculizumab treatment among patients, we have generated a PNH cohort including 12 PNH patients treated with Eculizumab. All patients included in the study had previously a minimum of ≥12 months on treatment with the drug (ten receiving 900 mg every 14 days, and two patients on 1200 mg every 14 days because breakthrough hemolysis). We have collected samples during two Eculizumab cycles (4 weeks) at different points during treatment: before and after Eculizumab injection and in the intermediate week. We have searched for correlations between clinical and hematological parameters, complement genetic findings, and deposition of C3 fragments on erythrocytes and plasma levels of complement activation components.Results: We report the CR1 genotypes, complement and hematological determinations in 12 PNH patients during their treatment with Eculizumab. We have established that concentrations of free Eculizumab above 110 µg/mL completely inhibit serum hemolytic activity. Consistent with this, in our patient cohort, most patients with levels of free Eculizumab close or below 110 µg/mL exhibited traces of C5b9 and/or CH50. In general, lowest levels of free Eculizumab correlate with higher levels of C5b9. Our results indicate that proper monitoring of PNH patients would be useful to optimize Eculizumab dosage. We have 3 patients that showed symptoms of intravascular hemolysis (high LDH and hemosiderinuria) despite having a negative CH50 accompanied with sufficient free Eculizumab levels. Further studies are currently being done to elucidate the causes. We have found a correlation between CR1 haplotype, red cellsopsonization and C3 plasma levels: H/L individuals present higher % of C3 positive erythrocytes and low C3 plasma levels. Two of these patients also had low C4 plasma levels, one of them presenting also low levels of FH. These individuals are currently being studied to determine whether these low levels are due to genetic factors or consumption. We found a correlation between levels of bilirubin and % of reticulocytes; patients who had more than the 30% of their erythrocytes opsonized presented higher percentage of reticulocytes and bilirubin in plasma, which could be taken as indicatives of slight extravascular hemolysis. In this regard, individuals carrying the CR1 L allele might require special attention. DisclosuresOjeda:Alexion Pharmaceuticals: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Fores:Alexion Pharmaceuticals: Consultancy, Speakers Bureau. Villegas-Martinez:Alexion Pharmaceuticals: Consultancy, Speakers Bureau. Rodriguez-Cordoba:Alexion Pharmaceuticals: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau.

Prophylactic Eculizumab Use in Kidney Transplantation: A Review of the Literature and Report of a Case with Atypical Hemolytic Uremic Syndrome

Atypical hemolytic uremic syndrome (aHUS) is a very rare disease, which presents with microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury. Progression to end-stage renal disease (ESRD) from acute kidney injury is observed in 60% of aHUS cases. The prognosis of aHUS patients who undergo kidney transplantation (Ktx) is generally poor, but these patients should be treated prophylactically with eculizumab to prevent recurrence after transplantation. An 18-year-old man was referred to our center with a history of rapid progression to ESRD with unknown etiology. He had anemia, thrombocytopenia, high levels of LDH, and indirect bilirubin and creatinine on initial laboratory results. Our diagnosis was aHUS due to initial results, normal level of ADAMTS activity, and lack of predisposing factors seen in typical HUS. We planned to perform genetic analysis for the patient and the donor candidate (mother). The variations found on exon 7 of the CFH gene had not been reported previously. According to PolyPhen analysis, this mutation was reported as a potential cause for aHUS. We decided to perform Ktx under eculizumab prophylaxis. Weekly administration of prophylaxis was extended to 1 month. The graft functioned immediately after Ktx. The patient has completed his first year uneventfully in our follow-up, with a creatinine 0.79 mg/dl at his last control visit. We found favorable results of an aHUS case successfully treated with kidney transplantation combined with short-term prophylactic eculizumab therapy.

Post-streptococcal glomerulonephritis associated with atypical hemolytic uremic syndrome: to treat or not to treat with eculizumab?

A 7-year-old male with poststreptococcal glomerulonephritis (PSGN) developed hemolytic uremic syndrome (HUS) and achieved remission. He was treated with eculizumab for 1 year. The eculizumab was discontinued and the patient remained in remission. This is the 10th reported case of PSGN associated with HUS. The histopathological feature observed at the 1-year follow-up was indistinguishable from the expected findings in an individual with healed PSGN without associated HUS. The relatively good prognosis in most prior cases and the absence of any reported recurrences strongly suggest that this form of atypical HUS does not warrant long-term eculizumab therapy.

Electron-dense deposit in renal transplant patients on eculizumab may be drug-derived

ABSTRACTEculizumab is a monoclonal antibody that inhibits the conversion of complement protein C5 to C5a and C5b. Eculizumab has been used to treat some disorders of complement regulation owing to its ability to inhibit terminal complement activation. The efficacy of eculizumab in reducing complement-mediated microvascular injury in renal allografts is currently the subject of trials. Electron-dense deposit was detected in allograft biopsies from three highly sensitized recipients of renal transplants, all of whom had received prophylactic eculizumab therapy. In two cases, the deposit was probably drug-derived whilst in the third case the deposit was probably derived from recurrent disease. The cases demonstrate the potential difficulty in interpreting electron-dense deposit in renal allograft biopsies, particularly in the setting of eculizumab therapy.

Background Paper for the update of meningococcal vaccination recommendations in Germany: use of the serogroup B vaccine in persons at increased risk for meningococcal disease.

In December 2013 Bexsero® became available in Germany for vaccination against serogroup B meningococci (MenB). In August 2015 the German Standing Committee on Vaccination (STIKO) endorsed a recommendation for use of this vaccine in persons at increased risk of invasive meningococcal disease (IMD). This background paper summarizes the evidence underlying the recommendation. Bexsero® is based on surface protein antigens expressed by about 80% of circulating serogroup B meningococci in Germany. The paper reviews available data on immunogenicity and safety of Bexsero® in healthy children and adolescents; data in persons with underlying illness and on the effectiveness in preventing clinical outcomes are thus far unavailable.STIKO recommends MenB vaccination for the following persons based on an individual risk assessment: (1) Persons with congenital or acquired immune deficiency or suppression. Among these, persons with terminal complement defects and properdin deficiency, including those under eculizumab therapy, are at highest risk with reported invasive meningococcal disease (IMD) incidences up 10,000-fold higher than in the general population. Persons with asplenia were estimated to have a ~ 20-30-fold increased risk of IMD, while the risk in individuals with other immune defects such as HIV infection or hypogammaglobulinaemia was estimated at no more than 5-10-fold higher than the background risk. (2) Laboratory staff with a risk of exposure to N. meningitidis aerosols, for whom an up to 271-fold increased risk for IMD has been reported. (3) Unvaccinated household (-like) contacts of a MenB IMD index case, who have a roughly 100-200-fold increased IMD risk in the year after the contact despite chemoprophylaxis. Because the risk is highest in the first 3 months and full protective immunity requires more than one dose (particularly in infants and toddlers), MenB vaccine should be administered as soon as possible following identification of the serogroup of the index case.

Atypical haemolytic uraemic syndrome treated with the complement inhibitor eculizumab: the experience of the Australian compassionate access cohort.

This study aimed to report the clinical characteristics and outcomes of Australian patients treated with eculizumab for atypical haemolytic uraemic syndrome (aHUS). A retrospective cohort study was undertaken of all patients in Australia treated with eculizumab provided in a compassionate access programme for a clinical diagnosis of aHUS using prospectively collected clinical data. A total of 10 patients with a median age of 23.5 years (interquartile range (IQR) 24.83 years) received compassionate access eculizumab for aHUS in Australia. Eight patients were female, and three had a family history of aHUS. Three received eculizumab for an initial acute aHUS presentation, three for relapsing and refractory acute aHUS, two for de novo aHUS post-renal transplantation, and one each for aHUS recurrence post-transplantation and facilitation of transplantation with a history of aHUS. The median duration of eculizumab therapy has been 911.5 days (IQR 569 days) with a cumulative exposure of 9184 days. At baseline all patients had renal and extra-renal aHUS involvement, with up to three non-renal organs affected. All but one patient, who died from uncontrollable gastrointestinal aHUS manifestations, have continued. The nine continuing patients achieved remission of aHUS. Two of the four patients requiring renal replacement therapy (RRT) at eculizumab commencement subsequently ceased RRT. Clinical events occurring in this cohort while on eculizumab treatment included neutropenia (two), posterior reversible encephalopathy syndrome (one), cardiomyopathy (one), pulmonary embolus (one), antibody-mediated rejection resulting in renal graft failure (one), iron deficiency (one), gastrointestinal haemorrhage (one) and death (one). Eculizumab has been an effective therapy for aHUS in this cohort, including when other therapies have failed.

Timing of eculizumab therapy for C3 glomerulonephritis.

Eculizumab is an anti-C5 antibody that inhibits C5 cleavage and prevents the generation of the terminal complement complex C5b-9. Eculizumab is licensed to treat paroxysmal nocturnal haemoglobinuria or atypical haemolytic uraemic syndrome (aHUS). Clinical trials are ongoing for C3 glomerulopathy. Given the unfamiliarity of physicians with these rare diseases and the variability of clinical presentation, a delayed initiation of eculizumab therapy is common. Thus, the question arises as to what extent improvement of kidney function may be expected when patients have been dialysis dependent for weeks or months already when eculizumab is initiated. Furthermore, given the high cost and potential adverse effects of eculizumab, the question arises of when to stop therapy because of futility when patients with kidney-only manifestations remain dialysis dependent. In literature reports, eculizumab was stopped as early as after 3 weeks because the patient remained dialysis dependent. In this issue of CKJ, Inman et al. report on eculizumab-induced reversal of dialysis-dependent kidney failure from C3 glomerulonephritis, illustrating both the potential benefit of eculizumab for this complement-mediated disease and the need for lengthy therapy—dialysis independency was reached after 5 months of eculizumab. Indeed, there are reports of renal function recovery when eculizumab was initiated after 4 months on dialysis and of recovery of renal function 2.0–3.5 months after initiation of eculizumab in dialysis-dependent patients with C3 glomerulopathy or aHUS.

Efficacy and safety of eculizumab in childhood atypical hemolytic uremic syndrome in Japan.

Atypical hemolytic uremic syndrome (aHUS) is a severe life-threatening disease with frequent progression to end-stage renal disease (ESRD). Eculizumab, a humanized anti-C5 monoclonal antibody targeting the activated complement pathway, has recently been introduced as a novel therapy against aHUS. We, therefore, investigated the efficacy and safety of eculizumab in Japanese pediatric patients. We retrospectively analyzed clinical course and laboratory data of the first ten children with aHUS treated with eculizumab nationwide. Seven patients were resistant to plasma therapy and three were dependent on it. Causative gene mutations were found in five patients. Two patients had anti-complement factor H autoantibody. Three patients had a family history of thrombotic microangiopathy (TMA). After initiation of eculizumab, all patients immediately achieved hematological remission and could successfully discontinue plasma therapy. The median periods to normalization of platelet count, lactate dehydrogenase levels and disappearance of schistocytes were 5.5, 17 and 12 days, respectively. Nine patients recovered their renal function and the median period to terminate renal replacement therapy (RRT) was 3 days. However, two patients progressed to ESRD and required chronic RRT at the last observation. No patients had a relapse of TMA under regular eculizumab therapy. No serious adverse events occurred during the follow-up period. Eculizumab is efficacious and well-tolerated therapy for children with aHUS. Although pathogenic mutations could not be detected in five patients, all patients showed immediate normalization of hematological abnormalities, strongly suggesting complement-related aHUS. This prompt hematological amelioration can become an indicator for therapeutic efficacy of eculizumab. However, appropriate indications and optimal duration of the treatment remain unclear.

Sensitive, reliable and easy-performed laboratory monitoring of eculizumab therapy in atypical hemolytic uremic syndrome

Complement C5 inhibitor eculizumab treatment in atypical hemolytic uremic syndrome is effective, but associated with high costs. Complement inhibition monitoring in these patients has not been standardized. In this study we evaluated novel functional assays for application in routine follow-up.We documented that the Wieslab® complement screen assay showed a sensitivity of 1–2% of C5 activity by adding purified C5 or normal human serum to a C5 deficient serum. All the patient samples obtained during the treatment course, were completely blocked for terminal complement pathway activity for up to four weeks after the eculizumab infusion. Levels of complexes between eculizumab and C5 were inversely correlated to the complement activity (p=0.01). Moreover, titrating serum from eculizumab-treated patients into normal serum revealed that eculizumab was present in excess up to four weeks after infusion.Thus, we demonstrate sensitive, reliable and easy-performed assays which can be used to design individual eculizumab dosage regimens.

Eculizumab in Typical Hemolytic Uremic Syndrome (HUS) With Neurological Involvement

In typical hemolytic uremic syndrome (HUS) approximately 25% of patients show central nervous system (CNS) involvement often leading to serious long-term disabilities. We used the C5-complement inhibitor Eculizumab as rescue therapy.From 2011 to 2014, 11 children (median age 22 months, range 11–175) with enterohemorrhagic Escherichia coli-positive HUS requiring dialysis who had seizures (11/11) and/or were in a stupor or coma (10/11) were treated with Eculizumab. Two patients enrolled on the Safety and Efficacy Study of Eculizumab in Shiga-Toxin Producing E coli Hemolytic-Uremic Syndrome (STEC-HUS) each received 6 doses of Eculizumab, 3 patients 2 doses, and 6 patients 1 dose. Laboratory diagnostics of blood samples and magnetic resonance imaging (MRI) were performed as per center practice. Data were analyzed retrospectively.Cranial MRI was abnormal in 8 of 10 patients with findings in the basal ganglia and/or white matter. A 2-year-old boy with severe cardiac involvement and status epilepticus needed repeated cardio-pulmonary resuscitation and extracorporeal membrane oxygenation. He died 8 days after start of Eculizumab treatment. Two patients with hemorrhagic colitis and repeated seizures required artificial ventilation for 6 and 16 days, respectively. At the time of discharge, 1 patient showed severe neurological impairment and 1 mild neurological impairment. The 8 surviving patients experienced no further seizures after the first dose of Eculizumab. Three patients showed mild neurological impairment at discharge, whilst the remaining 5 showed no impairment. The platelets normalized 4 days (median) after the first dose of Eculizumab (range 0–20 days). The mean duration of dialysis after the first dose of Eculizumab was 14.1 ± 6.1 days.In children with typical HUS and CNS involvement early use of Eculizumab appears to improve neurological outcome. In severe HUS cases which progress rapidly with multiple organ involvement, late treatment with Eculizumab seems to show less benefit. We speculate that prophylactic Eculizumab therapy before development of neurological symptoms could be advantageous.

Effective eculizumab therapy followed by BMT in a boy with paroxysmal nocturnal hemoglobinuria.

A 9-year-old boy with paroxysmal nocturnal hemoglobinuria/aplastic anemia syndrome (PNH/AA) developed hemolytic crisis after receiving immunosuppressive therapy. Eculizumab dramatically relieved the signs and symptoms and then he safely underwent unrelated bone marrow transplantation, suggesting the feasibility and effectiveness of eculizumab before stem cell transplantation in children with PNH/AA in hemolytic crisis.

Atypical Hemolytic Uremic Syndrome Recurrence after Renal Transplantation: C3-Glomerulonephritis as an Initial Presentation.

Risk for atypical hemolytic uremic syndrome (aHUS) recurrence after renal transplantation is low with an isolated membrane cofactor protein mutation (MCP). We report the case of a 32-year-old woman with a MCP who underwent kidney transplantation with a good evolution at 12 months. At 15 and 35 months, 2 episodes of thrombotic microangiopathy (TMA), after a miscarriage and a preeclampsia, were misinterpreted as triggered by tacrolimus. After each episode however serum creatinine returned to baseline. Five years after transplantation, she had a self-limited rhinosinusitis followed 3 weeks later by an oliguric renal failure. Her complement profile was normal. Graft biopsy showed C3 glomerulonephritis with no “humps” on electron microscopy. No significant renal function improvement followed methylprednisolone pulsing. A second biopsy showed severe acute TMA lesions with C3 glomerular deposits. Despite weekly eculizumab for 1 month, dialysis was resumed. A new workup identified the “at-risk” complement factor H haplotype. Thus, aHUS recurrence should be ruled out in aHUS patients considered at low recurrence risk when a TMA is found in graft biopsy. Prompt eculizumab therapy should be considered to avoid graft loss as aHUS recurrence can first present as a C3 glomerulonephritis.

Assessing complement blockade in patients with paroxysmal nocturnal hemoglobinuria receiving eculizumab

AbstractParoxysmal nocturnal hemoglobinuria (PNH) is characterized by intravascular hemolysis, which is effectively controlled with eculizumab, a humanized monoclonal antibody that binds complement protein 5 (C5). The residual functional activity of C5 can be screened using a 50% hemolytic complement (CH50) assay, which is sensitive to the reduction, absence, and/or inactivity of any components of the classical and terminal complement pathway. Little data exist on complement blockade during treatment. From 2010 to 2012, clinical data, hemolysis biomarkers, complement assessment, and free eculizumab circulating levels were systematically measured immediately before every injection given to 22 patients with hemolytic PNH while receiving eculizumab therapy. During the study, 6 patients received ≥1 red blood cell transfusion. Lack of detectable CH50 activity (defined by CH50 ≤ 10% of normal values) was found in 184 samples (51%) and was significantly associated with lower lactate dehydrogenase levels (P = .002). Low levels of circulating free eculizumab (<50 µg/mL) correlated with detectable CH50 activity (CH50 > 10%; P = .004), elevated bilirubin levels (P < .0001), and the need for transfusions (P = .034). This study suggests that both CH50 activity and circulating free eculizumab levels may help physicians to manage PNH patients receiving eculizumab.

Complement Inhibition in the Treatment of SLE-Associated Thrombotic Thrombocytopenic Purpura.

Thrombotic thrombocytopenic purpura (TTP) is a well-described complication of systemic lupus erythematosus (SLE).1 Historically, plasma exchange has been the mainstay of treatment for TTP as well as for other thrombotic microangiopathies.2 Recently, the complement inhibitor eculizumab has demonstrated efficacy in treating atypical hemolytic uremic syndrome (aHUS).3 Whether eculizumab therapy could be beneficial in the treatment of TTP is unknown. We report a case of pediatric SLE-associated TTP treated with eculizumab, in conjunction with steroids, plasma exchange, and additional immunosuppressant therapies.

Necrotizing Fasciitis in Paroxysmal Nocturnal Hemoglobinuria.

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, progressive, and life-threatening hematopoietic stem cell disorder characterized by complement-mediated intravascular hemolysis and a prothrombotic state. Patients with PNH might have slightly increased risk of infections due to complement-associated defects subsequent to CD59 deficiency. Here, we report a rare case of a 65-year-old male patient with necrotic ulcers on both legs, where the recognition of pancytopenia and microthrombi led to the diagnosis of PNH based on FLAER (FLuorescent AERolysin) flow cytometric analysis. He was subsequently started on eculizumab therapy, with starting and maintenance doses set as per drug labelling. Progression of the patient's leg ulcers during follow-up, with fulminant tissue destruction, purulent discharge, and necrotic patches, led to a later diagnosis of necrotizing fasciitis due to Pseudomonas aeruginosa and Klebsiella pneumonia infection. Courses of broad-spectrum antibiotics, surgical debridement, and superficial skin grafting were applied with successful effect during ongoing eculizumab therapy. This case highlights the point that it is important to maintain treatment of underlying disorders such as PNH in the presence of life-threatening infections like NF.