Eculizumab Treatment Research Articles

Outcome of children with Shiga toxin-associated haemolytic uraemic syndrome treated with eculizumab: a matched cohort study.

Treatment with eculizumab in Shiga toxin-associated haemolytic and uraemic syndrome (STEC-HUS) remains controversial despite its increasing utilization. The aim of our study was to evaluate the outcomes of children treated with eculizumab for STEC-HUS in a single-centre matched cohort study. Data were retrospectively collected from medical records of children diagnosed with STEC-HUS. The outcomes of patients treated with eculizumab for STEC-HUS were compared with those of a control group of untreated patients matched for age, sex and severity of acute kidney injury with a 1:2 matching scheme. Eighteen children (median age 40.6 months) with STEC-HUS treated with eculizumab were compared with 36 matched control patients (median age 36.4 months) who did not receive eculizumab. All patients survived in the two groups. Within 1 month of HUS onset, the evolution of haematological and renal parameters did not differ between the two groups. At 12 months of follow-up, renal outcome was not significantly different between the two groups. At the last follow-up, the prevalence of decreased glomerular filtration rate in the eculizumab group (27%) was not statistically different from that in controls (38%), as was the prevalence of proteinuria and high blood pressure. Children who received eculizumab more often had extrarenal sequelae during follow-up. Eculizumab treatment appeared to be safe in children with STEC-HUS. The benefit of eculizumab on renal and extrarenal outcomes in STEC-HUS could not be established based on our findings. However, efficacy and safety are not best assessed by the observational design and small sample size of our study. Randomized controlled trials are thus required to determine the efficacy of eculizumab in this indication.

Reduced membrane attack complex formation in umbilical cord blood during Eculizumab treatment of the mother: a case report

BackgroundAtypical hemolytic uremic syndrome (aHUS) is a disorder of the microvasculature with hemolytic anemia, thrombocytopenia and acute kidney injury. Nowadays, aHUS is successfully treated with eculizumab, a humanized, chimeric IgG2/4 kappa antibody, which binds human complement C5 and blocks generation of C5a and membrane-attack-complex.Case presentationA 25-year-old woman with end stage renal disease due to relapsing atypical hemolytic uremic syndrome had a relapse of the disease during pregnancy. She was treated with eculizumab. We measured reduced formation of the membrane-attack complex in newborn’s umbilical cord vein blood using the sensitive and specific Palarasah-Nielsen-ELISA.ConclusionsEculizumab treatment of the mother with end stage renal disease may cause reduced innate immunity which could render newborns more susceptible to infections.

Best abstract award. The electrophysiological assessment of eculizumab treatment for Guillain–Barré syndrome

Best abstract award. The electrophysiological assessment of eculizumab treatment for Guillain–Barré syndrome

Different Levels of Incomplete Terminal Pathway Inhibition by Eculizumab and the Clinical Response of PNH Patients.

Background: Eculizumab blocks the lytic complement pathway by inhibiting C5 and has become the standard of care for certain complement-mediated diseases. Previously, we have shown that strong complement activation in vitro overrides the C5 inhibition by Eculizumab, which accounts for residual terminal pathway activity.Results: Here we show that the levels of residual hemolysis in ex vivo assays differ markedly (up to 3.4-fold) across sera collected from different paroxysmal nocturnal hemoglobinuria (PNH) patients on Eculizumab treatment. This large variability of residual activity was also found in sera of healthy donors, thus cross-validating the findings in patients. While PNH patients with residual lytic activities of 11–30% exhibited hemolysis levels around the upper limit of normal (i.e., plasma LDH of ~250 u/L), as expected for PNH patients on Eculizumab therapy, we found sustained and markedly increased LDH levels of around 400 u/L for the patient with the highest residual activity of 37%. Furthermore, the clinical history of nine out of 14 PNH patients showed intravascular breakthrough hemolysis at the time of documented infections despite ample amounts of administered Eculizumab and/or experimentally determined excess over C5.Conclusion: The occurrence of extraordinary high levels of residual terminal pathway activity in PNH patients receiving Eculizumab is rare, but can impair the suppression of hemolysis. The commonly observed low levels of residual terminal pathway activity seen for most PNH patients can exacerbate during severe infections and, thus, can cause pharmacodynamic breakthrough hemolysis in PNH patients treated with Eculizumab.

Anti-complement Treatment for Paroxysmal Nocturnal Hemoglobinuria: Time for Proximal Complement Inhibition? A Position Paper From the SAAWP of the EBMT.

The treatment of paroxysmal nocturnal hemoglobinuria has been revolutionized by the introduction of the anti-C5 agent eculizumab; however, eculizumab is not the cure for Paroxysmal nocturnal hemoglobinuria (PNH), and room for improvement remains. Indeed, the hematological benefit during eculizumab treatment for PNH is very heterogeneous among patients, and different response categories can be identified. Complete normalization of hemoglobin (complete and major hematological response), is seen in no more than one third of patients, while the remaining continue to experience some degree of anemia (good and partial hematological responses), in some cases requiring regular red blood cell transfusions (minor hematological response). Different factors contribute to residual anemia during eculizumab treatment: underlying bone marrow dysfunction, residual intravascular hemolysis and the emergence of C3-mediated extravascular hemolysis. These two latter pathogenic mechanisms are the target of novel strategies of anti-complement treatments, which can be split into terminal and proximal complement inhibitors. Many novel terminal complement inhibitors are now in clinical development: they all target C5 (as eculizumab), potentially paralleling the efficacy and safety profile of eculizumab. Possible advantages over eculizumab are long-lasting activity and subcutaneous self-administration. However, novel anti-C5 agents do not improve hematological response to eculizumab, even if some seem associated with a lower risk of breakthrough hemolysis caused by pharmacokinetic reasons (it remains unclear whether more effective inhibition of C5 is possible and clinically beneficial). Indeed, proximal inhibitors are designed to interfere with early phases of complement activation, eventually preventing C3-mediated extravascular hemolysis in addition to intravascular hemolysis. At the moment there are three strategies of proximal complement inhibition: anti-C3 agents, anti-factor D agents and anti-factor B agents. These agents are available either subcutaneously or orally, and have been investigated in monotherapy or in association with eculizumab in PNH patients. Preliminary data clearly demonstrate that proximal complement inhibition is pharmacologically feasible and apparently safe, and may drastically improve the hematological response to complement inhibition in PNH. Indeed, we envision a new scenario of therapeutic complement inhibition, where proximal inhibitors (either anti-C3, anti-FD or anti-FB) may prove effective for the treatment of PNH, either in monotherapy or in combination with anti-C5 agents, eventually leading to drastic improvement of hematological response.

A.01 Relieving the burden of myasthenia gravis: eculizumab reduces exacerbation, hospitalization and rescue therapy rates

Background: Patients with anti-acetylcholine receptor antibody-positive (AChR+) generalized myasthenia gravis (MG) unresponsive to conventional treatment experience greater disease burden than responsive patients. This is partly due to exacerbations, which may result in significant healthcare resource utilization. Eculizumab is well tolerated and gives clinically meaningful benefits in these patients. We evaluated the effect of long-term eculizumab treatment on exacerbations, hospitalizations and rescue therapy in the REGAIN study and its open-label extension. Methods: Exacerbations were defined as clinical worsening/deterioration, MG crises or rescue therapy usage; pre-study exacerbations/hospitalizations were defined from patient records. Event rates adjusted for patient-years were calculated for all patients in the pre-study year, patients receiving placebo during REGAIN, and patients receiving eculizumab during REGAIN and its open-label extension (median exposure, 27.5 months [range, 22 days–42.8 months]); rates were compared using a Poisson regression model. Results: Eculizumab treatment reduced exacerbations by 65% (p=0.0057), hospitalizations by 71% (p=0.0316) and rescue therapy use by 66% (p=0.0072) versus placebo. Eculizumab treatment reduced exacerbations by 74% and hospitalizations by 83% (both p<0.0001) versus the pre-study year. Conclusions: Long-term eculizumab treatment reduces disease burden and healthcare resource utilization, demonstrating continuing improvements in clinical endpoints that lead to additional meaningful outcomes for patients with AChR+ generalized MG. (NCT01997229, NCT02301624).

PF734 PATIENT PREFERENCES FOR THE TREATMENT OF PAROXYSMAL NOCTURNAL HEMOGLOBINURIA: RESULTS OF A PATIENT SURVEY OF RAVULIZUMAB (ALXN1210) AND ECULIZUMAB

Background:Since 2007, eculizumab has transformed the management of paroxysmal nocturnal hemoglobinuria (PNH). However, it has a treatment burden associated with q2w dosing. Recently, the FDA approved ravulizumab for PNH treatment. Ravulizumab administered q8w demonstrated noninferiority to eculizumab in two phase 3 trials on all primary and key secondary efficacy measures. In view of these two treatment options, it is important to consider patient preference in determining a treatment plan for these patients (pts).Aims:To assess patient preference for ravulizumab or eculizumab treatment, in clinical trial substudy ALXN1210‐PNH‐302 s.Methods:The substudy enrolled PNH pts who participated in the extension period of the phase 3 study (ALXN1210‐PNH‐302) and provided informed consent. In the phase 3 study, adult PNH pts stable on eculizumab for at least 6 months received ravulizumab or eculizumab in accordance with protocol for 26 wks (randomized period). All pts in the extension period received ravulizumab. In the substudy, patient treatment preference was evaluated at one time point using an 11‐item PNH‐specific Patient Preference Questionnaire (PNH‐PPQ©). Prior to the administration of the PNH‐PPQ, pts must have received at least two doses of ravulizumab during the extension period. Differences in preference between ravulizumab and eculizumab were examined with an exact binomial test (Q1), frequency distributions (Q2–3), and paired t‐tests (Q4–11), with P < 0.05 considered statistically significant. Standardized effect sizes (d) were calculated for differences between evaluations of ravulizumab and eculizumab on Q4‐11.Results:Of 98 pts enrolled, 95 pts from 8 countries (European Union, North America, and Australia) completed PNH‐PPQs per protocol for analysis. The mean age of responders was 50 years (range: 22–78); 56% were male and 44% female. Mean time since diagnosis was 14 years (range: 2–48) and the mean number of days between the last randomized study treatment and completion of PNH‐PPQ was 306 (range: 196–457). Overall, 93% of pts (n = 88) preferred ravulizumab vs 7% (n = 7; P < 0.001) who had no preference (n = 6) or preferred eculizumab (n = 1) (Table). With regard to specific aspects of treatment, ravulizumab was widely preferred on frequency of infusions (98%), ability to plan activities (98%), overall quality of life (88%), convenience of receiving treatment (85%), and effectiveness of medication until the next infusion (78%). Among pts who preferred eculizumab or had no preference, side effects of treatment (n = 52; 55%) and anxiety related to infusions (n = 49; 51%) were the leading factors in determining their choice. Frequency of infusions was selected by the most respondents (n = 41; 43%) as the most important factor determining treatment preference, followed by overall quality of life (n = 22; 23%). Moderate to large effect sizes were observed for factors favoring ravulizumab over eculizumab, including the frequency of infusions disrupting everyday life (d = –1.46, P < 0.001), feeling fatigued after infusions (d = –0.56, P < 0.001), and being able to enjoy life while receiving treatment (d = 0.88, P < 0.001).Summary/Conclusion:In this clinical substudy of eculizumab‐experienced PNH pts, a vast majority preferred ravulizumab due to reduced infusion frequency (q8w vs q2w), ability to plan activities, overall quality of life, convenience of treatment, and effectiveness of medication compared to eculizumab. The study had a global outreach and imparts important patient perspective for treatment of PNH when there is more than one treatment option.image

PB1867 USE OF THERAPY WITH COMPLEMENT INHIBITOR AND THROMBOPOIETIN RECEPTOR AGONISTS IN TREATMENT OF PATIENT WITH SAA/PNH. CLINICAL CASE.

Background:Aplastic anemia (AA) is severe blood system disease, in which more than half of patients may have PNH clone, and there may occur associated variants AA with PNH (AA/PNH). The most frequently observed is the development of classical hemolytic PNH at AA remission, but possibly a combination of the two diseases. For such cases, there is a positive experience of AA combined treatment with immunosupressive therapy (IST) and targeted therapy using complement activation inhibitors. With resistant AA a therapeutic optionis possible using thrombopoietin receptor agonists.Aims:To treat of patient with SAA/PNH in absence of possibility of full use of ISTMethods:A clinical observation of a 53‐year‐old female with AA/PNH in the course of the disease is presented. Since 1994 patient, aged 53 yrs, has been under our supervision. The diagnosis was established according to a comprehensive examination, with severity determination in accordance to international criteria. The examination used morphological, histological, immunological (including highly sensitive flow cytometry), biochemical methods. No compatible donor for bone marrow transplantation was found. Anti‐lymphocyte globulin (ALG), cyclosporin‐A (CyA), Eculizumab and thrombopoietin receptor agonists were used in treatment.Results:ALG and cyclosporine treatment gave only a temporary effect – an improvement in hemogram parameters and a reduction in transfusion dependence. CyA doses were reduced (about 3 mg per day) due to adverse effects. The possibilities of active IST were also limited by comorbidities, including chronic hepatitis B. Since 1999, signs of chronic intravascular hemolysis and hemolytic crises have been observed. Flow cytometry have detected PNH clone. Subsequently, according to ICNN protocol testing data, from 2011 to the present, the clone size was determined 96‐99% with a predominance of type III erythrocytes. According to repeated bone marrow assessments, severe aplasia with pancytopenia in the peripheral blood was maintained. Anemia persisted up to 65 g/dL with transfusion dependence (up to 12‐16 doses of red blood cells per year), leukopenia within 0.9‐1.5 x109/l and thrombocytopenia 5‐15 x109/l with cutaneous hemorrhagic syndrome. On 2013, after vaccination with meningococcal vaccine, Eculizumab treatment was started according to the standard scheme with achievement of an adequate control of hemolysis. Clinical manifestations of hemolysis are absent; the level of LDH does not exceed 1.5 ULN. Therapy continues to the present. Until 2015, CyA therapy was periodically resumed due to the persistence of SAA criteria. In 2013‐2015 the patient additionally received thrombopoetin agonist therapy: Romiplostimum (4‐6 ug/kg once a week) with breaks every 3‐4 months. Two months after the start of therapy, a clinical effect was obtained – a decrease in hemorrhagic syndrome. After 3 months, there was a trend towards an increase in platelet levels. At present, severe leukopenia (1.0 – 2.2 x109/l) and neutropenia (0.5‐0.7x109/l) persist. At the same time, the platelet level is 30‐70 x109/l without spontaneous hemorrhages, since January 2018 the patient does not receive blood transfusions and hemoglobin stays at 10.2‐11.0 g/dL. Also there has been a significant improvement in the quality of life.Summary/Conclusion:This case demonstrates the possibility of a significant improvement in the course of sAA/PNH (including quality of life) in the absence of a sufficient effect of IST, but adequate target control of hemolysis and the use of thrombopoietin receptor agonists.

PS1118 IDENTIFICATION OF MIRNA SIGNATURES CORRELATING WITH CLINICAL OUTCOMES IN APLASTIC ANAEMIA

Background: There are limited data regarding the effectiveness and safety of either eculizumab or immunosuppressive therapy (IST) when used concomitantly in patients with paroxysmal nocturnal hemoglobinuria (PNH) and aplastic anemia (AA). The International PNH Registry (NCT01374360) is a prospective, multinational, observational study to collect data on the long-term efficacy and safety of eculizumab treatment. Aims: To evaluate the safety and effectiveness of IST in patients with PNH and AA who are treated concomitantly with eculizumab. Methods: Patients enrolled in the PNH Registry on or before January 1, 2018, with known demographics and enrollment date, who (1) ever reported a diagnosis of AA, (2) were ever treated with eculizumab, and (3) were ever treated with IST (defined as cyclosporine and/or anti-thymocyte globulin) were included. Patients were categorized into 3 cohorts: (I) IST before eculizumab, no overlap; (II) IST before eculizumab, with overlap; (III) eculizumab before IST, with overlap (Panel A). For this analysis, baseline was defined as the later of initiation of IST or PNH disease onset, and last follow-up as the last follow-up on IST (cohort I) or concomitant IST and eculizumab (cohorts II and III). Laboratory values were calculated as the most recent value within 6 months of baseline and last follow-up, and change was analyzed using generalized linear mixed models adjusted for baseline and cohort. Numbers of units of packed red blood cells (RBCs) received were summarized as rates with 95% confidence intervals (CIs) between baseline and last follow-up. Results: The analysis included 283 patients (cohort I, n = 88; cohort II, n = 162; cohort III, n = 33), although not all patients had available laboratory test results at baseline. Results of interest for IST by treatment sequence are shown in Panel B. Overall, 54.1% of patients were female and 85.2% were white. Mean (standard deviation) age at baseline was 35.5 (16.43) years in cohort I, 36.7 (18.21) years in cohort II, and 41.3 (17.05) years in cohort III. Adjusted mean platelet and neutrophil counts improved in patients receiving IST before concomitant eculizumab (cohort II) as well as in those receiving eculizumab before IST, with overlap (cohort III; Panel B) as expected with treatment with IST. Adjusted mean reticulocyte counts and hemoglobin levels both showed a clinically meaningful increase after baseline in cohort II; a clinically meaningful decrease in reticulocyte count was also observed after baseline in cohort III (Panel B). Patients receiving eculizumab prior to concomitant IST (cohort III) had a higher rate (95% CI) of RBC transfusions per patient-years during follow-up (7.2 [6.7, 7.8]) than patients receiving IST prior to concomitant eculizumab (cohort II; 2.8 [2.7, 2.9]). Cohort III also had a higher rate (95% CI) of infections per 100 patient-years during follow-up (23.4 [5.8, 93.4]) than cohort I (1.9 [0.5, 7.4]) and cohort II (4.3 [2.8, 6.6]).Summary/Conclusion: The numbers of patients with available data were limited due to the fact that the Registry was not designed to evaluate the effectiveness of IST. Nevertheless, our findings suggest that IST was effective when used concomitantly with eculizumab in this clinical setting, regardless of the sequence for initiation of treatment with IST or eculizumab. Differences in RBC transfusion rates and laboratory parameters observed across cohorts possibly reflect underlying AA.

Eculizumab Treatment for Refractory Generalized Myasthenia Gravis

Myasthenia gravis (MG) is an autoimmune disease of the neuromuscular junction mainly caused by anti-nicotinic acetylcholine receptor (AChR) antibodies. Complements are known to play a prominent role in the pathogenesis of MG. Long-term remission may not necessarily be achieved in MG patients with conventional therapies. Recently, complement inhibitor, the humanized monoclonal anti-C5 antibody eculizumab, complement inhibitor, was approved for patients with anti-AChR antibody-positive generalized refractory MG in Japan. In this review, we focus on the role of complements in the pathogenesis of MG and the action mechanism, efficacy, and future prospects of eculizumab.

PS1119 PNH CLONE SIZE BY FLOW CYTOMETRY AND ITS CORRELATION TO PIG GENE MUTATION

Background:Routine diagnosis of paroxysmal nocturnal hemoglobinuria (PNH) is based on flow cytometric measurement of PNH clone in RBC and granulocyte. However there is no well‐established consensus on the clinically significant size of PNH clone.Aims:So we investigated whether quantitative results of PNH clone size measured by flow cytometry (FCM) correlate with mutant burden of PIG gene.Methods:A total of 89 specimens from 63 patients whose PNH clone size was ≥0.1% by FCM was enrolled. We performed ultra‐deep sequencing for PIGA, PIGM and PIGX genes on these 89 consecutive specimens. Also, we followed up 6 patients who were treated with Eculizumab and analyzed their laboratory changes including hemoglobin, lactate dehydrogenase level, PNH flow cytometry and PIG gene mutant burden. Treatment response was evaluated every 6 months.Results:Sixteen out of 63 patients had >10% granulocyte PNH clone and they all had PIG gene mutation. Fifteen (93.8%) had PIGA mutation and one (6.3%) PIGM mutation. Patients with >15% RBC PNH clone (n = 12) all had PNH‐related symptoms (p <0.001). Granulocyte clone size showed better correlation with VAF than RBC clone size (Granulocyte r = 0.61, p = 0.01, RBC r = 0.39, p = 0.14). On the other hand, RBC clone size was better reflective of PNH‐related symptoms with a cut‐off of 15% (p <0.001). We found no significant laboratory parameter for prediction of Eculizumab treatment response.Summary/Conclusion:Patients with >10% granulocyte PNH clone by FCM were always accompanied by PIG gene mutation. Those with >15% RBC PNH clone by FCM all had PNH‐related symptoms. Weak correlation between granulocyte clone size and VAF of PIG gene mutation implies that granulocyte clone reflects the real PNH clonal burden.image

Severe and malignant hypertension are common in primary atypical hemolytic uremic syndrome

Malignant hypertension is listed among the causes of secondary thrombotic microangiopathy, but pathogenic mutations in complement genes have been reported in patients with hypertension-induced thrombotic microangiopathy. Here we investigated the frequency and severity of hypertension in 55 patients with primary atypical hemolytic uremic syndrome (aHUS). A genetic analysis was performed in all patients, and funduscopic examination was performed in all the patients with Grades 2 and 3 hypertension. A cohort of 110 patients with malignant hypertension caused by diseases other than aHUS served as control. Thirty-six patients with aHUS presented Grade 2 or Grade 3 hypertension and funduscopic examination showed malignant hypertension in 19. Genetic abnormalities in complement were found in 19 patients (37% among patients with malignant hypertension). Plasmapheresis was performed in 46 patients and 26 received eculizumab. Renal and hematological responses were significantly lower after plasmapheresis (24%) than after eculizumab (81%). Renal survival was significantly higher in patients treated with eculizumab (85% at one, three and five years) compared to patients who did not receive this treatment (54%, 46% and 41%), respectively. Response to eculizumab was independent of hypertension severity and the presence of complement genetic abnormalities. Among patients with malignant hypertension caused by other diseases the prevalence of thrombotic microangiopathy was very low (5%). Thus, severe and malignant hypertension are common among patients with aHUS and eculizumab treatment leads to a higher renal survival when compared to plasmapheresis. However, thrombotic microangiopathy is uncommon among patients presenting with malignant hypertension caused by diseases other than aHUS.

Complement-mediated thrombotic microangiopathy or sepsis with disseminated intravascular coagulation -what is primary?

Thrombotic microangiopathies (TMAs) are induced by several underlying conditions; most are resolved by treating background disease. Eculizumab is a human monoclonal antibody that blocks the final stage of the complement system and effectively treats atypical hemolytic uremic syndrome (aHUS). In this report, we present a patient with TMA related to sepsis- induced coagulopathy, who was successfully treated with eculizumab.A 44-year-old woman, who had no special medical history or familial history of TMAs, hospitalized for acute kidney injury.Blood tests revealed a decreased platelet count, disseminated intravascular coagulation (DIC), renal dysfunction, hemolysis, and infection. Although the coagulation disorder improved with intensive care, the low platelet count, elevated lactate dehydrogenase levels, and renal dysfunction persisted. Our investigations subsequently excluded thrombotic thrombocytopenic purpura and Shiga toxin-producing Escherichia coli-induced HUS. Plasma exchange only improved lactate dehydrogenase levels. We clinically diagnosed this case as atypical HUS and started eculizumab treatment. The patient's platelet count increased, her renal dysfunction improved. We encountered a case of complement-mediated TMA accompanied by DIC, which was successfully treated with eculizumab. Further studies are necessary to support the optimal use of eculizumab for TMA with background diseases.

An Ex Vivo Test of Complement Activation on Endothelium for Individualized Eculizumab Therapy in Hemolytic Uremic Syndrome

Although primary atypical hemolytic uremic syndrome (aHUS) is associated with abnormalities in complement genes and antibodies to complement factor H, the role ofcomplement in secondary aHUS remains debatable. We evaluated the usefulness of an exvivo test to: (1) detect complement activation within the endothelium in primary and secondary aHUS, (2) differentiate active disease from remission, (3) monitor the effectiveness of eculizumab therapy, and (4) identify relapses during eculizumab dosage tapering and after discontinuation of treatment. Case series. 121 patients with primary aHUS and 28 with secondary aHUS. Serum samples were collected during acute episodes, following remission, and during eculizumab treatment and were assessed using a serum-induced exvivo C5b-9 endothelial deposition test. Serum-induced C5b-9 deposition on cultured microvascular endothelium was quantified by calculating the endothelial area covered by C5b-9 staining; values were expressed as percentage of C5b-9 deposits induced by a serum pool from healthy controls. Testing with adenosine diphosphate-activated endothelium demonstrated elevated C5b-9 deposits for all untreated patients with aHUS independent of disease activity, while testing with unstimulated endothelium demonstrated deposits only in active disease. Similar findings were observed in secondary aHUS. Serum-induced C5b-9 deposits on activated and unstimulated endothelium normalized during eculizumab treatment. 96% (22/23) of patients receiving eculizumab at extended 3- or 4-week dosing intervals demonstrated normal C5b-9 deposits on activated endothelium, despite most patients having CH50Eq (serum complement activity) > 20 UEq/mL, indicating that adequate complement control was achieved even with incomplete blockade of circulating C5. During eculizumab dosage tapering or after treatment discontinuation, all patients experiencing relapses versus only 6% (1/17) of those in stable remission had elevated C5b-9 deposits on unstimulated endothelium. The C5b-9 endothelial deposition test can be performed in only specialized laboratories. Findings on eculizumab dosage tapering need to be confirmed with longitudinal monitoring of C5b-9 deposition. The C5b-9 endothelial deposition assay may represent an advance in our ability to monitor aHUS activity and individualize therapy.

Differential miRNA expression profile and proteome in plasma exosomes from patients with paroxysmal nocturnal hemoglobinuria

Paroxysmal Nocturnal Hemoglobinuria (PNH) is a clonal disease of blood cells caused by the lack of glycosyl phosphatidyl inositol anchored proteins bound to the cell membrane. In consequence, erythrocytes lead to intravascular hemolysis upon complement activation, which promotes high risk of thrombosis, intravascular hemolytic anemia, and bone marrow failure in patients. The mechanisms of thrombosis in PNH are still poorly understood. Treatment with eculizumab reduces intravascular hemolysis and thrombotic risk, but not in all cases. Exosomes are extracellular vesicles released by cells and whose secretion is closely related to the inflammatory status. They participate in cell communication by activating signaling pathways and transferring genetic material and proteins to host cells. In consequence, exosomes may serve as surrogate biomarkers for the prognosis and/or diagnosis of a disease. Isolation of exosomes was carried out from healthy controls and from three groups of PNH patients, i.e. i) with no eculizumab treatment; ii) under treatment with eculizumab that have not suffered thrombosis; and iii) under treatment with eculizumab but that have suffered thrombosis. The miRNAome and proteome was analyzed using plasma focus miRNAs PCR panel and LC-MS analysis respectively. We found differential expression of miRNAs miR-148b-3p, miR-423-3p, miR29b-3p, miR15b-5p, let-7e-5p, miR126-3p, miR-125b-5p and miR-376c-3p as well as hemoglobin, haptoglobin, protein S and C4-binding protein in healthy controls vs PNH patients. Our results warrant further research and provide new information on the content of exosomes that could play a role in the hypercoagulable state in this disease.

Eculizumab Is Safe and Effective as a Long-term Treatment for Protein-losing Enteropathy Due to CD55 Deficiency.

Loss of the complement inhibitor CD55 leads to a syndrome of early-onset protein-losing enteropathy (PLE), associated with intestinal lymphangiectasia and susceptibility to large-vein thrombosis. The in vitro and short-term treatment benefits of eculizumab (C5-inhibitor) therapy for CD55-deficiency have been previously demonstrated. Here we present the 18-months treatment outcomes for 3 CD55-deficiency patients with sustained therapeutic response. Three CD55-deficiency patients received off-label eculizumab treatment. Clinical and laboratory treatment outcomes included frequency and consistency of bowl movements, weight, patient/parent reports of overall well-being, and serum albumin and total protein levels. Membrane attack complex deposition on leukocytes was tested by flow cytometry, before and during eculizumab treatment. Marked clinical improvement was noted in all 3 patients with resolution of PLE manifestations, that is, diarrhea, edema, malabsorption, overall well-being, growth, and quality of life. In correlation with the clinical observations, we observed progress in all laboratory outcome parameters, including increase in albumin and total protein levels, and up to 80% reduction in membrane attack complex deposition on leukocytes (P < 0.001). The progress persisted over 18 months of treatment without any severe adverse events. CD55-deficiency patients present with early-onset diarrhea, edema, severe hypoalbuminemia, abdominal pain, and malnutrition. Targeted therapy with the terminal complement inhibitor eculizumab has positive clinical and laboratory outcomes in PLE related to CD55 loss-of-function mutations, previously a life-threatening condition. Our results demonstrate the potential of genetic diagnosis to guide tailored treatment, and underscore the significant role of the complement system in the intestine.

Eculizumab Use for Kidney Transplantation in Patients With a Diagnosis of Atypical Hemolytic Uremic Syndrome

IntroductionRecurrence of atypical hemolytic uremic syndrome (aHUS) in renal allografts is common, leading to dialysis and graft failure. Pretransplant versus posttransplant initiation of eculizumab treatment in patients with aHUS has not been rigorously investigated. We hypothesized eculizumab pretransplant would reduce dialysis incidence posttransplant.MethodsOf patients enrolled in the Global aHUS Registry (n = 1549), 344 had ≥1 kidney transplant. Of these, 188 had received eculizumab. Eighty-eight patients (47%) were diagnosed with aHUS and received eculizumab before, and during, their most recent transplant (group 1). A total of 100 patients (53%; group 2) initiated eculizumab posttransplantation. This second group was subdivided into those diagnosed with aHUS before (n = 52; group 2a) or after (n = 48; group 2b) their most recent transplant.ResultsWithin 5 years of transplantation, 47 patients required dialysis; the risk of dialysis after transplantation was significantly increased in group 2b (hazard ratio [HR] 4.6; confidence interval [CI] 1.7–12.4) but not 2a (HR 2.3; CI 0.9–6.2). Graft function within 6 months of transplantation was significantly better in group 1 (median estimated glomerular filtration rate of 60.6 ml/min per 1.73 m2) compared with 31.5 and 9.6 ml/min per 1.73 m2 in groups 2a (P = 0.004) and 2b (P = 0.0001), respectively. One meningococcal infection (resolved with treatment) and 3 deaths (deemed unrelated to eculizumab) were reported.ConclusionsOutcomes for transplant patients with aHUS treated with eculizumab were improved compared with previous reports of patients with aHUS not treated with eculizumab. Our findings suggest delayed aHUS diagnosis and therefore treatment is associated with an increased risk of dialysis posttransplantation and reduced allograft function.

Treatment of hemolytic uremic syndrome related to Bordetella pertussis infection \u2014is plasma exchange or eculizumab use necessary?

BackgroundBordetella pertussis infection is a known trigger of atypical hemolytic uremic syndrome (HUS). For patients suspected of having atypical HUS, prompt plasma exchange/infusion (PE/PI) or eculizumab (ECZ) treatment is recommended.Case presentationWe report a 1-month-old female infant who was admitted with a severe cough and a B. pertussis-positive sputum culture. She was born at 38 weeks gestation and did not have a family history of renal diseases. Hemophagocytic syndrome was suspected and she was transferred to our hospital 17 days after her initial admission. One day later, she developed acute kidney injury and was diagnosed with HUS triggered by B. pertussis infection. Her plasma complement levels were low and her kidney function continued to worsen over the next few days. However, prior to starting ECZ treatment, her kidney function improved spontaneously; she did not receive PE/PI or ECZ. She was discharged 46 days after her initial hospitalization, without complications. A genetic workup revealed no mutations in CFH, CFI, CFB, C3, MCP, THBD, or DGKE.ConclusionsThis case demonstrates that B. pertussis infection-related HUS may resolve spontaneously. The decision to treat during the acute phase is challenging because B. pertussis often affects infants suspected of having atypical HUS. However, ECZ may not be the first treatment option for patients with B. pertussis infection-related HUS unless they show an indicated genetic abnormality; if ECZ is used, early discontinuation should be considered.

Thrombotic Microangiopathies Associated with Pregnancy: Diagnostic and Therapeutic Challenges

Several serious disorders may present during pregnancy or postpartum with thrombotic microangiopathy (p-TMA). Signs of microangiopathic hemolytic anemia and thrombocytopenia may arise due to pregnancy complications such as severe preeclampsia (sPE) and HELLP-syndrome (hemolysis, elevated liver enzymes, and low platelets) or severe independent diseases: atypical hemolytic uremic syndrome (aHUS), thrombotic thrombocytopenic purpura (TTP). Recent evidence and clinical similarities suggest a link sPE/HELLP to aHUS, a disease of excessive activation of the alternative complement pathway. Pregnancy-associated aHUS is a severe disorder with a high risk of maternal and fetal morbidity and mortality, defined by the occurrence of comlement-mediated TMA without ADAMTS13 deficiency. Triggered by pregnancy and another complement-amplifying conditions women develop the syndrome, leading to a disastrous hemolytic disease characterized by diffuse endothelial damage and platelet consumption. Delivery is the treatment of choice of sPE and HELLP, but can lead to progression in case of aHUS: even now it is associated with unfavorable outcomes.We observe 116 women with p-TMA: 43 aHUS, 36 HELLP, 35 sPE, 2 TTP. PE diagnosed in accordance with the WHO criteria of 2008. HELLP- in accordance with Tenessee criteria (laboratory parameters normalized beyond 48-72 hours after delivery). TTP was associated with ADAMTS 13 deficiency <10%. We compare results with those of 28 healthy pregnant women. All patients with aHUS and TTP received plasma therapy (30-40ml/kg), in 20 cases of aHUS eculizumab was administered.The overall outcomes differed depending on the TMA type. Condition of PE/HELLP patients improved only with supportive treatment in 28-72 hours after delivery. Women with TTP received successful prolonged plasma exchange. Survival was the worst in aHUS patients 32(74.4%), among other patients with TMA no one died. Neonates survived in 33(76,7%) mothers with aHUS, 70(98,6%) with PE and HELLP. Sepsis diagnosed only in aHUS-15(34,9%). Acute kidney injury registered in 100% aHUS patients, neurological symptoms had 61%, respiratory distress syndrome- 55%, dilated cardiomyopathy- 16,7%. 61,3% required hemodialysis, 51,8%- respiratory care. All of patients who died had 2 “waves” of TMA: first wave damaged 2-5 organs without any proved infections, but treated with combination of antibiotics. Second TMA wave was fatal due to superimposed septic disorders, resistant to antibiotic therapy. Patients on eculizumab treatment had more severe disease at debut with shorter history of aHUS and responded well to eculizumab (recovery of TMA laboratory signs - 87,2%, but a full course was not held anyone). Survival of aHUS patients on eculizumab treatment was 81,4%, without it - 66,5%.All p-TMA are life-threatening disorders with different therapeutic approaches. Start therapy before specification of the diagnosis can be carried out with the use of plasma exchange for 24-48 hours. Patients with aHUS have a worst prognosis and require the rapid differential diagnosis. The revealed regularities allow us to assume the presence of the following triggers for the development of aHUS: surgical interventions and gestational complications. Early specific therapy complement inhibitor in complex with escalation treatment of multiple organ failure can contribute to the improvement of aHUS outcomes. DisclosuresNo relevant conflicts of interest to declare.

The Importance of Eculizumab in Paroxysmal Nocturnal Hemoglobinuria: A Cohort Study

IntroductionParoxysmal nocturnal hemoglobinuria (PNH) is a rare, often progressively debilitating and life-threatening acquired disease characterized by chronic, complement-mediated intravascular hemolysis. PNH is characterized by the deficiency of the endogenous glycosyl phosphatidylinositol-anchored complement regulatory proteins CD55 and CD59 and other proteins on the surface of blood cells, which results in chronic uncontrolled activation of the complement system at the site of the PNH cells and intravascular hemolysis and thrombosis. PNH may present in the absence of an underlying bone marrow disorder (BMD), as a condition secondary to BMDs, such as aplastic anemia (AA) or myelodysplastic syndrome, or as sub-clinical PNH. In this cohort study we will report clinical findings, management options and eculizumab response of 38 PNH cases in our clinic.Materials and MetodWe followed 38 PNH cases in this cohort study. We used flow cytometric PNH clone detection test since 1993 but HAM's test and sucrose lysis test were the only tests for the PNH diagnosis in older cases. We used eculizumab in 20 of our patients who had transfusion dependent chronic intravascular hemolysis and/or thrombosis. All of of the patients were vaccinated for Neisseria meningitides, Pneumococcus and Hemophilus influenza type B prior to 2 weeks of initiation of Eculizumab. Eculizumab was administered 600 mg/day for 4 weeks and dosage was elevated to 900 mg/day at week 5, then 900 mg/day every other week as maintenance therapy. The response to therapy was evaluated by LDH, blood cell counts and haptoglobin levels. Clinical and laboratory findings, management options and treatment effect on survival curves were evaluated.FindingsThirty-eight PNH patients who were followed in our clinic since 1985 were enrolled in this study. Twenty of 38 were female and the median age was 35 years (ranging from 18 - 62). The oldest one has been followed for 32 years. Chronic hemolytic anemia and at least one lineage of cytopenia were seen in each patient during diagnosis.Fifteen patients were diagnosed as AA and were treated with immunosuppressive therapy before PNH diagnosis. Following AA diagnosis, PNH was diagnosed on average 35 months (three to 192 months) . One of the patients was diagnosed as MDS and followed-up for five years with this diagnosis. Twenty-two of the cases were de-novo PNH disease. Thrombotic complications were seen at the diagnosis in two patients. Unfortunately, we also have seen thrombotic complications in 10 more patients during follow-up period before eculizumab availability.Five of our patients were lost on eight, 14, 60, 86 and 260 months after their diagnosis. We lost two of them with infection and two of them with thrombotic complications. Fifth patient that we lost at 260 months of her follow-up had complete response with eculizumab and was deceased following a fall from height. Two of our patients went to abroad for treatment. Six of them were lost to follow-up. We currently follow 25 of 38 patients. We still use eculizumab in 20 of our patients. We used eculizumab in median 8 months after PNH diagnosis (One to 360 months). In 15 patients, transfusion dependent chronic intravascular hemolysis was the main indication and for the remaining 5 patients thrombosis was the main indication. Quality of life parameters changed significantly in all of the patients and we didn't observe any new thrombotic episodes. We used eculizumab as an important treatment option for a median 63 months (eight to 98 months) and we didn't encounter any side effects other than mild headache and flu-like symptoms in 5 of the cases.Discussion and conclusionPNH is a life-threatening disease and four of the patients in our cohort died in median 37 months of their diagnosis. Although thrombosis was the main mortality and morbidity reason in our cohort, we didn't see any thrombotic episodes under eculizumab treatment. Even in induction period of the therapy, both clinical and laboratory findings improved significantly with Eculizumab. None of our patients needed transfusion on eculizumab treatment. The survival of our PNH patients on eculizumab is excellent and we didn't lose any of our patients since induction of eculizumab therapy.In conclusion, eculizumab is the first disease-modifying, targeted therapy for PNH and its availability has radically changed the management of patients with this rare disease. DisclosuresYenerel:Alexion: Honoraria, Speakers Bureau.