Post-Transplant Cyclophosphamide versus Anti-Thymocyte Globulin in Patients with Hematological Malignancies Treated with Allogeneic Hematopoietic Stem Cell Transplantation from Haploidentical and Matched Unrelated Donors: A Real-Life Experience.

Background: Post-transplant cyclophosphamide (PTCY) is widely used as graft versus host disease (GvHD) prophylaxis in allogeneic hematopoietic stem cell transplant (HSCT) recipients, with reported clinical benefits in patients who underwent transplant from a matched unrelated donor (MUD). However, real-life data on clinical efficacy and safety of PTCY in haploidentical and MUD transplantations are still poor. Methods: In our real-life retrospective observational study, we included a total of 40 consecutive adult patients who underwent haploidentical or MUD HSCT for various hematological malignancies and who received PTCY (n = 24) or ATG (n = 16) as GvHD prophylaxis at Hematology Units from hospitals of Salerno and Avellino, Italy, and clinical outcomes were compared. Results: We showed protective effects of PTCY against disease relapse with the relapse rate after transplantation of 16% versus 50% in the ATG arm (p = 0.02). All-cause mortality was lower (36% vs. 75%; p = 0.02) and the 2-year overall survival was slightly superior in patients administered PTCY (61% vs. 42%; p = 0.26). Conclusions: We support the use of PTCY, even in a real-life setting; however, the optimization of this protocol should be further investigated to better balance relapse prevention and GvHD prophylaxis.

Management of erythropoietic protoporphyria with cholestatic liver disease: A case report.

Erythropoietic protoporphyria (EPP) is a rare metabolic disease of the heme biosynthetic pathway where an enzymatic dysfunction results in protoporphyrin IX (PPIX) accumulation in erythroid cells. The porphyrins are photo-reactive and are responsible for severe photosensitivity in patients, thus drastically decreasing their quality of life. The liver eliminates PPIX and as such, the main and rare complication of EPP is progressive cholestatic liver disease, which can lead to liver failure. The management of this complication is challenging, as it often requires a combination of approaches to promote PPIX elimination and suppress the patient's erythropoiesis. Here we described a 3-year follow-up of an EPP patient, with three episodes of liver involvement, aggravated by the coexistence of a factor VII deficiency. It covers all the different types of intervention available for the management of liver disease, right through to successful allogeneic hematopoietic stem cell transplantation.

The complement alternative pathway in paroxysmal nocturnal hemoglobinuria: From a pathogenic mechanism to a therapeutic target.

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare clonal, not malignant, hematological disease characterized by intravascular hemolysis, thrombophilia and bone marrow failure. While this latter presentation is due to a T-cell mediated auto-immune disorder resembling acquired aplastic anemia, the first two clinical presentations are largely driven by the complement pathway. Indeed, PNH is characterized by a broad impairment of complement regulation on affected cells, which is due to the lack of the complement regulators CD55 and CD59. The deficiency of these two proteins from PNH blood cells is due to the somatic mutation in the phosphatidylinositol N-acetylglucosaminyltransferase subunit A gene causing the disease, which impairs the surface expression of all proteins linked via the glycosylphosphatidylinositol anchor. The lack of the complement regulators CD55 and CD59 on PNH erythrocytes accounts for the hallmark of PNH, which is the chronic, complement-mediated intravascular hemolysis. This hemolysis results from the impaired regulation of the alternative pathway upstream in the complement cascade, as well as of the downstream terminal pathway. PNH represented the first indication for the development of anti-complement agents, and the therapeutic interception of the complement cascade at the level of C5 led to remarkable changes in the natural history of the disease. Nevertheless, the clinical use of an inhibitor of the terminal pathway highlighted the broader derangement of complement regulation in PNH, shedding light on the pivotal role of the complement alternative pathway. Here we review the current understanding of the role of the alternative pathway in PNH, including the emergence of C3-mediated extravascular hemolysis in PNH patients on anti-C5 therapies. These observations provide the rationale for the development of novel complement inhibitors for the treatment of PNH. Recent preclinical and clinical data on proximal complement inhibitors intercepting the alternative pathway with the aim of improving the treatment of PNH are discussed, together with their clinical implications which are animating a lively debate in the scientific community.

Impact of second-degree related donor on the outcomes of T cell-replete haploidentical transplantation with post-transplant cyclophosphamide.

Donor selection may contribute to improve clinical outcomes of T cell-replete haploidentical stem cell transplantation (Haplo-SCT) with post-transplant cyclophosphamide (PT-Cy). Impact of second-degree related donor (SRD) was not fully elucidated in this platform. We retrospectively compared the outcome of patients receiving Haplo-SCT either from a SRD (n = 31) or a first-degree related donor (FRD, n = 957). Median time to neutrophil and platelet recovery did not differ between a SRD and a FRD transplant (p = 0.599 and 0.587). Cumulative incidence of grade II-IV acute graft-versus host disease (GVHD) and moderate-severe chronic GVHD was 13% and 19% after SRD vs 24% (p = 0.126) and 13% (p = 0.395) after FRD transplant. One-year cumulative incidence of non-relapse mortality (NRM) was 19% for SRD and 20% for FRD (p = 0.435) cohort. The 3-year probability of overall survival (OS) and progression-free survival (PFS) was 42% vs 55% (p = 0.273) and 49% vs 35% (p = 0.280) after SRD and FRD transplant, respectively. After propensity score adjustment or matched pair analysis, the outcome of patients receiving Haplo-SCT from a SRD or a FRD did not differ in terms of NRM, OS, PFS, acute and chronic GVHD. Our results suggest that a SRD is a viable option for Haplo-SCT with PT-Cy when a FRD is not available.

Life expectancy and burden of late complications after reduced intensity conditioning allogeneic transplantation.

Reduced intensity conditionings (RIC) before after allogeneic hematopoietic stem cell transplantation (HSCT) allow older or unfit patients of being transplanted, but survival expectancy and burden of late complications are poorly described in this setting. All patients (N = 456) who were alive and relapse-free 2 years after HSCT following RIC were included. Cumulative incidences (CI), standardized incidence, or mortality, ratio (SIR or SMR), and competing risk models were used. The 10-year CIs of relapse and non-relapse mortality incidences were 13.9 and 13.4%, respectively. Seventy-eight patients died, late relapse being the most frequent cause of death leading to a SMR of 6.38 (95% CI, 5.1-8.0; p < 0.001). Among non-relapsing patients (n = 412), 30 died (SMR 4.38; 95% CI, 3.3-5.8: p < 0.001). A total of 37 patients developed 41 SM leading to a 10-year cumulative incidence of 12.9%, and a significant SIR relative to the general population (1.4). Finally, we found high CI of cardiovascular (CVC) and venous thromboembolic complications (VTE) (10-year CI; 15.1% and 11.7%, respectively). Older age was the only significant risk factor for CVC and VTE in multivariable analysis. In conclusion, with life expectancy rate of 70%, late survivors after RIC warrants long-term follow-up and active intervention on averting cardiovascular disease and screening cancers.

Discovering C3 targeting therapies for paroxysmal nocturnal hemoglobinuria: Achievements and pitfalls.

The treatment of paroxysmal nocturnal hemoglobinuria (PNH) was revolutionized by the introduction of the anti-C5 agent eculizumab, which resulted in sustained control of intravascular hemolysis, leading to transfusion avoidance and hemoglobin stabilization in at least half of all patients. Nevertheless, extravascular hemolysis mediated by C3 has emerged as inescapable phenomenon in PNH patients on anti-C5 treatment, frequently limiting its hematological benefit. More than 10 years ago we postulated that therapeutic interception of the complement cascade at the level of C3 should improve the clinical response in PNH. Compstatin is a 13-residue disulfide-bridged peptide binding to both human C3 and C3b, eventually disabling the formation of C3 convertases and thereby preventing complement activation via all three of its activating pathways. Several generations of compstatin analogs have been tested in vitro, and their clinical evaluation has begun in PNH and other complement-mediated diseases. Pegcetacoplan, a pegylated form of the compstatin analog POT-4, has been investigated in two phase I/II and one phase III study in PNH patients. In the phase III study, PNH patients with residual anemia already on eculizumab were randomized to receive either pegcetacoplan or eculizumab in a head-to-head comparison. At week 16, pegcetacoplan was superior to eculizumab in terms of hemoglobin change from baseline (the primary endpoint), as well as in other secondary endpoints tracking intravascular and extravascular hemolysis. Pegcetacoplan showed a good safety profile, even though breakthrough hemolysis emerged as a possible risk requiring additional attention. Here we review all the available data regarding this innovative treatment that has recently been approved for the treatment of PNH.

Eltrombopag Added to Immunosuppression in Severe Aplastic Anemia.

BACKGROUND: A single-group, phase 1-2 study indicated that eltrombopag improved the efficacy of standard immunosuppressive therapy that entailed horse antithymocyte globulin (ATG) plus cyclosporine in patients with severe aplastic anemia. METHODS: In this prospective, investigator-led, open-label, multicenter, randomized, phase 3 trial, we compared the efficacy and safety of horse ATG plus cyclosporine with or without eltrombopag as front-line therapy in previously untreated patients with severe aplastic anemia. The primary end point was a hematologic complete response at 3 months. RESULTS: Patients were assigned to receive immunosuppressive therapy (Group A, 101 patients) or immunosuppressive therapy plus eltrombopag (Group B, 96 patients). The percentage of patients who had a complete response at 3 months was 10% in Group A and 22% in Group B (odds ratio, 3.2; 95% confidence interval [CI], 1.3 to 7.8; P = 0.01). At 6 months, the overall response rate (the percentage of patients who had a complete or partial response) was 41% in Group A and 68% in Group B. The median times to the first response were 8.8 months (Group A) and 3.0 months (Group B). The incidence of severe adverse events was similar in the two groups. With a median follow-up of 24 months, a karyotypic abnormality that was classified as myelodysplastic syndrome developed in 1 patient (Group A) and 2 patients (Group B); event-free survival was 34% and 46%, respectively. Somatic mutations were detected in 29% (Group A) and 31% (Group Β) of the patients at baseline; these percentages increased to 66% and 55%, respectively, at 6 months, without affecting the hematologic response and 2-year outcome. CONCLUSIONS: The addition of eltrombopag to standard immunosuppressive therapy improved the rate, rapidity, and strength of hematologic response among previously untreated patients with severe aplastic anemia, without additional toxic effects. (Funded by Novartis and others; RACE ClinicalTrials.gov number, NCT02099747; EudraCT number, 2014-000363-40.).

Emerging drugs for the treatment of paroxysmal nocturnal hemoglobinuria.

INTRODUCTION: Eculizumab, the first anti-C5 monoclonal antibody approved for patients with paroxysmal nocturnal hemoglobinuria (PNH), has revolutionized the natural history of this disease, blocking intravascular hemolysis, reducing the risk of thromboembolic events, resulting in a significant improvement in survival and quality of life. However, the hematological response to eculizumab is extremely heterogeneous, with only one-third of PNH patients reaching normal hemoglobin levels. AREAS COVERED: This article reviews the current new drugs being investigated in phase II and III trials for adult PNH patients. Literature search was performed using Medline and Clinicaltrials.org databases. EXPERT OPINION: The new molecules have been classified according to the target of the complement system on which they act; we have novel terminal complement inhibitors, which target C5, and proximal complement inhibitors, which interfere with C3 or even further upstream (factor B and D). Ravulizumab is the first next-generation C5 inhibitor, approved by FDA and EMA, which reproduced the excellent results achieved with eculizumab, trying to improve the convenience of patients. However, unresolved issues remain, such as C3-mediated extravascular hemolysis, on which novel proximal complement inhibitors are showing their efficacy. Pegcetacoplan is the first C3-inihibitor approved by FDA. Long-term safety data for novel complement inhibitors are needed.

Addition of iptacopan, an oral factor B inhibitor, to eculizumab in patients with paroxysmal nocturnal haemoglobinuria and active haemolysis: an open-label, single-arm, phase 2, proof-of-concept trial.

BACKGROUND: The haematological benefit of standard-of-care anti-C5 treatment for haemolytic paroxysmal nocturnal haemoglobinuria is limited by residual intravascular haemolysis or emerging C3-mediated extravascular haemolysis. Therefore, the aim of this phase 2 study was to assess the safety, tolerability, pharmacokinetics and pharmacodynamics, and activity of the new complement factor B inhibitor, iptacopan, in patients with paroxysmal nocturnal haemoglobinuria who have active haemolysis despite anti-C5 therapy. METHODS: In this multicentre, open-label, single-arm, phase 2 trial, we enrolled adult patients (aged 18-80 years) with paroxysmal nocturnal haemoglobinuria who showed signs of active haemolysis despite receiving eculizumab treatment. Patients were enrolled at Federico II University Hospital (Naples, Italy), Hôpital Saint-Louis (Paris, France), and University Hospital Essen (Essen, Germany). For enrolment, patients were required to show lactate dehydrogenase more than 1·5-times the upper limit of normal and a paroxysmal nocturnal haemoglobinuria type 3 erythrocyte or granulocyte clone size of 10% or greater. Patients with bone marrow failure, on systemic steroid or immunosuppressive drugs, or with severe comorbidities were excluded from the study. Iptacopan was given orally as an add-on therapy at a dose of 200 mg twice daily. The primary endpoint was the effect of iptacopan on the reduction of chronic residual intravascular haemolysis measured as change in lactate dehydrogenase from baseline value to week 13. At 13 weeks, patients could opt into a long-term study extension (ongoing), allowing for modifications of standard treatment. This trial is registered at ClinicialTrials.gov, NCT03439839. FINDINGS: Between May 31, 2018, and April 9, 2019, ten patients had twice daily 200 mg iptacopan. Iptacopan resulted in marked reduction of lactate dehydrogenase from baseline versus at week 13 (mean 539 IU/L [SD 263] vs 235 IU/L [44], change from baseline -309·2 IU/L [SD 265·5], 90% CI -473·77 to -144·68, p=0·0081), associated with significant improvement of haemoglobin concentrations (mean 97·7 g/L [SD 10·5] vs 129·5 g/L [18·3] change from baseline 31·9 g/L [14·5], 90% CI 23·42-40·28, p<0·0001). All biomarkers of haemolysis improved on iptacopan treatment. Observed haematological benefits were maintained longer than the 13-week study period, throughout the study extension, including seven patients who stopped concomitant standard-of-care treatment and continued iptacopan as monotherapy. There were no deaths or treatment-related serious adverse events during the study period. Of three non-related serious adverse events, two occurred in the same patient (one during run-in and before exposure to iptacopan). INTERPRETATION: Iptacopan at a chronic dose of 200 mg twice daily was well tolerated without any major drug-related safety findings and shows lactate dehydrogenase reduction and haemoglobin normalisation in most patients with paroxysmal nocturnal haemoglobinuria at week 13 and beyond, even in monotherapy. On the basis of these data, iptacopan will be tested as monotherapy in pivotal trials investigating its haematological benefit in a broader paroxysmal nocturnal haemoglobinuria population. FUNDING: Novartis Institutes for Biomedical Research.

Long-term outcomes and risk factor analysis of steroid-refractory graft versus host disease after hematopoietic stem cell transplantation.

Steroid-refractory graft versus host disease (GVHD) represents a fearsome complication after allogeneic hematopoietic stem cell transplantation (HSCT). We conducted a retrospective study on outcomes and risk factors associated with acute and chronic steroid-refractory GVHD in a large cohort of 1207 patients receiving HSCT in Saint Louis Hospital between 2007 and 2017. Among patients who developed an acute and/or a chronic GVHD, the cumulative incidences of acute and chronic steroid-refractory disease were 31% and 48%, respectively, at day +100 and 1-year post-HSCT. Through a multivariable analysis we selected several risk factors associated with the development of a steroid-refractory disease. For acute GVHD steroid refractoriness, we identified (1) a very high disease risk index, (2) an unrelated donor, (3) the absence of in vivo T-depletion as GVHD prophylaxis, and (4) a reduced intensity conditioning regimen. For chronic GVHD, (1) the use of peripheral blood stem cells, (2) unrelated donors, and (3) absence of in vivo T-depletion were more likely associated with a steroid-refractory disease. After the construction of a multistate dynamic model, we found that the probability of being alive without relapse after the resolution of all GVHD episodes was about 36% in the long term.

Impact of donor age and kinship on clinical outcomes after T-cell-replete haploidentical transplantation with PT-Cy.

Donor selection contributes to improve clinical outcomes of T-cell-replete haploidentical stem cell transplantation (haplo-SCT) with posttransplant cyclophosphamide (PT-Cy). The impact of donor age and other non-HLA donor characteristics remains a matter of debate. We performed a multicenter retrospective analysis on 990 haplo-SCTs with PT-Cy. By multivariable analysis, after adjusting for donor/recipient kinship, increasing donor age and peripheral blood stem cell graft were associated with a higher risk of grade 2 to 4 acute graft-versus-host-disease (aGVHD), whereas 2-year cumulative incidence of moderate-to-severe chronic GVHD was higher for transplants from female donors into male recipients and after myeloablative conditioning. Increasing donor age was associated with a trend for higher nonrelapse mortality (NRM) (hazard ratio [HR], 1.05; P = .057) but with a significant reduced risk of disease relapse (HR, 0.92; P = .001) and improved progression-free survival (PFS) (HR, 0.97; P = .036). Increasing recipient age was a predictor of worse overall survival (OS). Risk of relapse was higher (HR, 1.39; P < .001) in patients aged ≤40 years receiving a transplant from a parent as compared with a sibling. Moreover, OS and PFS were lower when the donor was the mother rather than the father. Pretransplant active disease status was an invariably independent predictor of worse clinical outcomes, while recipient positive cytomegalovirus serostatus and hematopoietic cell transplant comorbidity index >3 were associated with worse OS and PFS. Our results suggest that younger donors may reduce the incidence of aGVHD and NRM, though at higher risk of relapse. A parent donor, particularly the mother, is not recommended in recipients ≤40 years.

Erythropoietin treatment in chronic phase chronic myeloid leukemia patients treated with frontline imatinib who developed late anemia.

BACKGROUND: Role of erythropoietin (EPO) in the treatment of late anemia in patients with Chronic Myeloid Leukemia (CML) is still undefined. METHODS: Fifty CML patients treated at 14 institutions with frontline imatinib for at least 12 months and in stable complete cytogenetic response who developed a late chronic anemia treated with EPO were retrospectively evaluated. RESULTS: Median time from imatinib start to EPO treatment was 42.2 months [interquartile range (IQR) 20.8-91.9]. Median Hb value at EPO starting time was 9.9 g/dL (IQR 8.9-10.3): Eleven patients (22.0%) were transfusion dependent. Alpha-EPO (40 000 UI weekly) was employed in 37 patients, beta-EPO (30 000 UI weekly) in 9 patients, zeta-EPO (40 000 UI weekly) in 2 patients, and darbepoetin (150 mcg/weekly) in the remaining 2 patients. On the whole, 41 patients (82.0%) achieved an erythroid response, defined as a stable (>3 months) improvement >1.5 g/dL of Hb level, and 9 patients (18.0%) indeed resulted resistant. Among responding patients, 10 relapsed after a median time from EPO start of 20.7 months (IQR 10.8-63.7). No EPO-related toxicity was observed. CONCLUSIONS: Results of EPO treatment for late chronic anemia during long-lasting imatinib therapy are encouraging, with a high rate of response.

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.

Eltrombopag for post-transplant cytopenias due to poor graft function.

Persistent cytopenia due to poor graft function (PoGF) is a relatively common complication which may affect up to 20% of patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT). Treatment options for PoGF remain limited, and reinfusion of additional HSC is often the only way to rescue hematopoiesis. Here we describe a retrospective single-center experience with the thrombopoietin-mimetic agent eltrombopag for the treatment of PoGF. Thirteen patients have received eltrombopag for either PoGF (n = 12) or primary graft failure (n = 1). In the 12 PoGF patients eltrombopag was started at the median time of 79 days after HSCT, due to persistent thrombocytopenia, with concomitant anemia and neutropenia in 7 and 3 patients, respectively. The treatment was started at the dose of 50 mg per day, and eventually increased up to 150 mg in case of lack of response. Hematological response was seen in 7 patients, with 6 complete responses. Hematological responses were seen both in patients with evidence of immune-mediated pathophysiology, and with possible infectious/iatrogenic causes. In responding patients, eltrombopag was discontinued in 6/7 patients without further relapse. These results suggest that eltrombopag is safe and possibly effective in the setting of the treatment of PoGF, and pave the way for future prospective studies.

The expression of inhibitor of bruton's tyrosine kinase gene is progressively up regulated in the clinical course of chronic lymphocytic leukaemia conferring resistance to apoptosis.

Chronic lymphocytic leukaemia (CLL) is the most common B-cell malignancy with a variable clinical outcome. Biomarkers of CLL progression are required for optimising prognosis and therapy. The Inhibitor of Bruton's tyrosine kinase-isoform α (IBTKα) gene encodes a substrate receptor of Cullin 3-dependent E3 ubiquitin ligase, and promotes cell survival in response to the reticulum stress. Searching for novel markers of CLL progression, we analysed the expression of IBTKα in the peripheral blood B-cells of CLL patients, before and after first line therapy causing remission. The expression of IBTKα was significantly increased in disease progression, and decreased in remission after chemotherapy. Consistently with a pro-survival action, RNA interference of IBTKα increased the spontaneous and Fludarabine-induced apoptosis of MEC-1 CLL cells, and impaired the cell cycle of DeFew B-lymphoma cells by promoting the arrest in G0/G1 phase and apoptosis. Consistently, RNA interference of IBTKα up regulated the expression of pro-apoptotic genes, including TNF, CRADD, CASP7, BNIP3 and BIRC3. Our results indicate that IBTKα is a novel marker of CLL progression promoting cell growth and resistance to apoptosis. In this view, IBTKα may represent an attractive cancer drug target for counteracting the therapy-resistance of tumour cells.