Transfusion-dependent Β-thalassemia Patients Research Articles

Combination of a TGF-β ligand trap (RAP-GRL) and TMPRSS6-ASO is superior for correcting β-thalassemia.

A recently approved drug that induces erythroid cell maturation (luspatercept) has been shown to improve anemia and reduce the need for blood transfusion in non-transfusion-dependent as well as transfusion-dependent β-thalassemia (BT) patients. Although these results were predominantly positive, not all the patients showed the expected increase in hemoglobin (Hb) levels or transfusion burden reduction. Additional studies indicated that administration of luspatercept in transfusion-dependent BT was associated with increased erythropoietic markers, decreased hepcidin levels, and increased liver iron content. Altogether, these studies suggest that luspatercept may necessitate additional drugs for improved erythroid and iron management. As luspatercept does not appear to directly affect iron metabolism, we hypothesized that TMPRSS6-ASO could improve iron parameters and iron overload when co-administered with luspatercept. We used an agent analogous to murine luspatercept (RAP-GRL) and another novel therapeutic, IONIS TMPRSS6-LRx (TMPRSS6-ASO), a hepcidin inducer, to treat non-transfusion-dependent BT-intermedia mice. Our study shows that RAP-GRL alone improved red blood cell (RBC) production, with no or limited effect on splenomegaly and iron parameters. In contrast, TMPRSS6-ASO improved RBC measurements, ameliorated splenomegaly, and improved iron overload most effectively. Our results provide pre-clinical support for combining TMPRSS6-ASO and luspatercept in treating BT, as these drugs together show potential for simultaneously improving both erythroid and iron parameters in BT patients.

Revisiting iron overload status and change thresholds as predictors of mortality in transfusion-dependent β-thalassemia: a 10-year cohort study.

Data on iron overload status and change thresholds that can predict mortality in patients with transfusion-dependent β-thalassemia (TDT) are limited. This was a retrospective cohort study of 912 TDT patients followed for up to 10years at treatment centers in Italy (median age 32years, 51.6% female). The crude mortality rate was 2.9%. Following best-predictive threshold identification through receiver operating characteristic curve analyses, data from multivariate Cox-regression models showed that patients with Period Average Serum Ferritin (SF) > 2145 vs ≤ 2145ng/mL were 7.1-fold (P < 0.001) or with Absolute Change SF > 1330 vs ≤ 1330ng/mL increase were 21.5-fold (P < 0.001) more likely to die from any cause. Patients with Period Average Liver Iron Concentration (LIC) > 8 vs ≤ 8mg/g were 20.2-fold (P < 0.001) or with Absolute Change LIC > 1.4 vs ≤ 1.4mg/g increase were 27.6-fold (P < 0.001) more likely to die from any cause. Patients with Index (first) cardiac T2* (cT2*) < 27 vs ≥ 27ms were 8.6-fold (P < 0.001) more likely to die from any cause. Similarly, results at varying thresholds were identified for death from cardiovascular disease. These findings should support decisions on iron chelation therapy by establishing treatment targets, including safe iron levels and clinically meaningful changes over time.

Audiologic and vestibular assessment in children and adolescents with transfusion dependent beta thalassemia major: The era of deferasirox film coated tablet

BackgroundHearing impairment has frequently been described in β-thalassemia patients with a significant impact on the patients’ quality of life. Most studies provided evidence of deferoxamine (DFO) dose-related ototoxicity, however, the data is scarce regarding deferasirox (DFX) as a sole iron chelator. AimWe aimed to assess the prevalence and risk factors of sensorineural hearing loss (SNHL) and vestibular dysfunction in regularly transfused β-thalassemia patients who had been treated with DFX film coated tablets. MethodsWe conducted a case control study on 57 transfusion dependent β-thalassemia patients with a mean age of 15.3 years who received DFX FCT as monotherapy for at least one consecutive year, and 57 healthy age and sex-matching controls. Comprehensive audiological evaluations using pure tone audiometry (PTA) and transient evoked otoacoustic emission (TEOAE) as well as vestibular evaluation using Video-nystagmography (VNG) were done. ResultsSNHL was identified in 12 patients (21.1 %) using PTA and a statistically significant difference was detected between controls and patients at 6 KHz and 12 KHz frequencies. A higher incidence of SNHL was detected using TEOAE, 22 patients (43.1 %) failed to pass TEOAE, with a statistically significant decrease in the signal at frequencies 1, 4 KHz bilaterally and at frequencies 1.5, 2 KHz in the right ear compared to controls. Canal paresis was detected in 21 (36.8 %) of thalassemic children using bithermal caloric test with significantly more unilateral weakness than control children (P = 0.008). We found no significant correlation between audio-vestibular dysfunction and age, sex, serum ferritin, frequency of blood transfusion and dose of DFX FCT in thalassemic children. ConclusionWe conclude that the incidence of SNHL and vestibular dysfunction was high among transfusion dependent β-thalassemia patients. Therefore, we recommend performing pre-treatment baseline audio-vestibular assessment and yearly audio-vestibular monitoring to early detect high risk patients and initiate timely management to prevent permanent damage.

When should gene therapy be considered for transfusion-dependent β-thalassemia patients?

When should gene therapy be considered for transfusion-dependent β-thalassemia patients?

A retrospective study of glucose homeostasis, insulin secretion, sensitivity/resistance in non- transfusion-dependent β-thalassemia patients (NTD- β Thal): reduced β-cell secretion rather than insulin resistance seems to be the dominant defect for glucose dysregulation (GD).

Non-transfusion - dependent β-thalassemias (NTD-βThal) can cause iron overload and serious iron-related organ complications as endocrine dysfunction, including glucose dysregulation (GD). We retrieved data of all NTD- β Thal patients referred consecutively to a single Outpatient Italian Clinic from October 2010 to April 2023. All patients underwent a standard 3-h oral glucose tolerance test (OGTT) for analysis of glucose homeostasis, insulin secretion and sensitivity/resistance (IR), using conventional surrogate indices derived from the OGTT. The collected data in NTD- β Thal patients were compared to 20 healthy subjects. Seventeen of 26 (65.3 %) NTD- β Thal patients (aged: 7.8 -35.1 years) had normal glucose tolerance, 1/26 (3.8 %) had impaired fasting glucose (IFG), 5/26 (19.2 %) impaired glucose tolerance (IGT), 1/26 (3.8%) IFG plus IGT and 2/26 (7.6%) plasma glucose (PG) level ≥155 mg/dL 1-h after glucose load. GD was observed exclusively in young adult patients; none of them had diabetes mellitus (DM). These findings were associated with a low insulinogenic index (IGI) and oral disposition index. HOMA-IR and QUICKI were not significantly different compared to controls. Interestingly, in young adult patients, ISI-Matsuda index was statistically higher compared to the control group, suggesting an increased insulin sensitivity. This study reported a high prevalence of GD in young adults with NTD- β Thal. The documented reduction of IGI rather than the presence of IR, indicates reduced insulin secretory capacity as the pathophysiological basis of dysglycemia that may represent a novel investigational path for future studies on the mechanism(s) responsible for GD in NTD- β Thal patients.

Safety and Efficacy of RM-001 (Autologous HBG1/2 Promoter-modified CD34+ Hematopoietic Stem and Progenitor Cells) in Patients with Transfusion-Dependent β-Thalassemia

Background: Reactivating fetal globin (HbF) is a promising treatment for β-hemoglobinopathies. Natural mutations in the promoter region of γ-globin genes ( HBG1/2) that disrupt the binding of the transcriptional repressors BCL11A could lead to a lifelong persistence of fetal γ-globin expression. Using gene editing to mimic these mutations should reactivate γ-globin in patients with transfusion-dependent β-thalassemia (TDT) and ameliorate the symptoms of patients. RM-001 is a novel cell therapy that uses non-viral, ex vivo CRISPR-Cas9 gene editing in autologous hematopoietic stem and progenitor cells (HSPCs) at the promoter of the γ-globin genes ( HBG1/2) to disrupt the binding site of BCL11A. Aims: ChiCTR2100053406 and ChiCTR2100052858 are ongoing multi-center, first-in-human studies of RM-001 for TDT. Here, we present available safety and efficacy results from 7 patients that have been dosed with RM-001. Methods: Patients (6-35 y of age) with TDT receiving packed red blood cell (pRBC) transfusions of ≥100 mL/kg/y or ≥10 units/y in the previous 2ys were eligible. Peripheral CD34+ HSPCs were collected by apheresis after mobilization with G-CSF and plerixafor. CD34+ cells were edited with CRISPR-Cas9 using a guide RNA specific for the binding site of BCL11A on the HBG1/2 promoter. Prior to RM-001 product infusion (day 0), patients received myeloablative conditioning with Busulfan from day-7 to day-3. Patients were monitored for stem cell engraftment/hematopoietic recovery, adverse events (AEs), Hb production, HbF and F-cell expression, and pRBC transfusion requirements. Bone marrow cells were obtained at 3, 6, 12 and 24 months after RM-001 infusion to measure the on-target allelic editing frequency using next-generation sequencing. Results: Data presented here for 7 TDT patients have been treated with RM-001. As of July 31, 2023, patients were followed up from 1 to 20 months and 5 of them have been followed up more than 15 months. Six patients have β 0/β 0 genotype (CD17/CD41-42, n=1; CD41-42/CD41-42, n=5) and the other has β 0/β + genotype (CD41-42/IVS-II-654). In addition to β-thalassemia (CD41-42/CD41-42), two patients also carry a Southeast Asian deletion of α-globin genes (– SEA/αα). Patients had received a mean of 55.8 units/y pRBC transfusions (range: 39-79.6 units/y). All patients received a single dose of RM-001 cells, and achieved both neutrophil and platelet engraftments 2 to 3 weeks after RM-001 infusion (neutrophil: day 11-19, platelet: day 10-22). All patients ceased pRBC transfusions within 1 month after RM-001 infusion and remained transfusion-free through the reported period (Figure). For the 6 patients that have been followed up more than 6 months, HbF reached 9g/dL at 4 month post-RM-001 infusion and continuously maintained over this level through the reported period. From 6 month post-RM-001 infusion, hemoglobin in all patients consists of HbF (97.6%-99.8%) and HbA2 only, including the fifth patient who has a β0/β+ genotype (99.5% HbF). Five participants have remained transfusion independent more than 15 months and the mean HbF in the first 4 patients was 11g/dL(10.9-11.3 g/dL) at 18 month post-RM-001 infusion. The safety profile was generally consistent with busulfan myeloablation and autologous hematopoietic stem cell transplantation. No RM-001 related SAE report. Summary/Conclusion: This updated data reported here from 7 patients with TDT infused with RM-001 demonstrated clinically meaningful increases in total hemoglobin (Hb) and HbF levels. All patients stopped receiving pRBC transfusions within 1 month after RM-001 infusion and remained transfusion-free through the time of this analysis. The safety profile of RM-001 is generally consistent with myeloablative conditioning and autologous hematopoietic stem cell transplantation. These results strongly support continued investigation of RM-001 as a potential cure for patients with TDT. Data will be updated for the presentation. Submitted on behalf of the RM-001 Investigators.

AsCas12a Gene Editing of HBG1/2 Promoters with EDIT-301 Results in Rapid and Sustained Normalization of Hemoglobin and Increased Fetal Hemoglobin in Patients with Severe Sickle Cell Disease and Transfusion-Dependent Beta-Thalassemia

Background: Sickle cell disease (SCD) and transfusion-dependent β-thalassemia (TDT) are hereditary blood disorders caused by mutations in the β-globin gene. Clinical evidence has demonstrated that increased fetal hemoglobin (HbF, α2γ2) can reduce or eliminate SCD and TDT complications. EDIT-301, an investigational gene-edited autologous hematopoietic stem cell medicine, has a unique genomic modification that mimics naturally occurring mutations of hereditary persistence of fetal hemoglobin in the γ-globin gene ( HBG1/2) promoters. These mutations reactivate γ-globin expression and increase HbF production. EDIT-301 is manufactured with a highly efficient and specific, proprietary gene editing nuclease, AsCas12a. In preclinical studies, edited CD34 + cells from patients with SCD or TDT increased HbF production in red blood cells (RBCs) sufficient for a therapeutic effect, including reduced sickling (SCD) and improved erythropoiesis (TDT). Aim: RUBY (NCT04853576) and EdiThal (NCT05444894) are Phase I/II, multicenter, open-label, single-arm studies evaluating the safety, efficacy, and tolerability of EDIT-301 in patients with severe SCD and TDT, respectively. As of June 28, 2023, 7 SCD patients and 2 TDT patients have received EDIT-301 treatment. Preliminary clinical efficacy and safety data are reported. Methods: Patients aged 18-50 years with severe SCD (defined as ≥2 severe vaso-occlusive events [VOEs] per year in the 2 years prior to informed consent [IC]) and patients aged 18-35 years with TDT (defined as at least 100 mL/kg/year or 10 U/year of packed RBC transfusions in the 2 years prior to IC) were eligible to enroll in RUBY and EdiThal, respectively. Autologous CD34 + hematopoietic stem and progenitor cells collected by apheresis after plerixafor (RUBY) or plerixafor + filgrastim (EdiThal) mobilization were edited at the HBG1/2 promoters with AsCas12a. After myeloablative conditioning with busulfan, patients received a single infusion of EDIT-301 (a minimum of 3 × 10 6 CD34 + cells/kg), and were monitored for engraftment, total hemoglobin (Hb), HbF, mean HbF concentration/F-cell (MCH-F/F-cell), percentage of F-cells, markers of hemolysis, transfusion requirement, VOEs (SCD only), and adverse events (AEs) for 24 months. Results: Based on a data cut of June 28, 2023, Patients 1-4 with SCD were 12-, 9-, 4-, and 4-months post-EDIT-301 infusion, respectively. Patients 5-7 with SCD were &amp;lt;1-month post-EDIT-301 infusion. Patients 1-2 with TDT were 3- and &amp;lt;1-months post-EDIT-301 infusion, respectively. Neutrophil and platelet engraftment were achieved after a mean (range) of 25 (23-29) and 27 (19-37) days in Patients 1-4 with SCD and on Day 23 and 26 in Patient 1 with TDT, respectively. There were no VOEs in SCD patients post-EDIT-301 infusion, compared with a mean (range) of 4.2 (3.0-5.5) VOEs/year in the 2 years before enrollment (n=6). Following EDIT-301 infusion, Hb levels rapidly increased to 14.2 (12.4-15.7) g/dL by Month 4 (n=4), reaching the normal physiological range, from a mean (range) of 10.5 (8.5-11.9) g/dL at baseline (n=5). By Month 4, the mean (range) HbF concentration was 6.8 (5.7-7.6) g/dL and HbF was &amp;gt;40% (n=4); Patients 3 and 4 had &amp;gt;50% HbF. Percentage of F-cells and MCH-F/F-cell also increased. Key markers of hemolysis improved or normalized in all patients with SCD. Patient 1 with TDT had a HbF concentration of 7.2 g/dL by Month 3, stopped receiving RBC transfusions 20 days after EDIT-301 infusion, and remained transfusion free through the 3-month period. Patient 2 with TDT also showed early improvements. The safety profile of EDIT-301 in both SCD and TDT was consistent with myeloablative conditioning with busulfan. No serious AEs were reported after EDIT-301 infusion. Conclusion: These data demonstrated successful engraftment, a rapid and sustained normalization of Hb as early as 4 months after infusion, an increase in HbF and percentage of F-cells, resolution of VOEs (SCD) and transfusion independence (TDT). In addition, there were improvements in key markers of hemolysis (SCD) and a favorable safety profile in EDIT-301-treated patients. EDIT-301 treatment showed promising results for the first clinical use of AsCas12a in both SCD and TDT patients after gene editing of the γ-globin gene ( HBG1/2) promoters. These findings support further investigation of EDIT-301 in the RUBY and EdiThal trials. Updated data with additional outcomes will be presented.

Gene Therapy of Transfusion-Dependent β-Thalassemia Patients with Quick Engraftment of Reinfused Hematopoietic Stem Cells: An Investigator-Initiated Trial of KL003

Introduction In recent years, autologous hematopoietic stem cell (HSC)-based gene therapy has emerged as one of the most promising curative therapies for the treatment of severe hereditary anemia, including β-thalassemia major. Although several clinical trials of gene therapy for β-thalassemia major patients have been completed in developed countries, clinical data of gene therapy remain scarce for patients in developing countries. These patients are often in poor clinical condition because of severe iron overload and insufficient blood transfusion due to limited blood supply. They account for the majority of the β-thalassemia major patients in developing countries. Unlike in developed countries, most β-thalassemia major patients in developing countries cannot survive to adulthood as a consequence of irregular treatments due to the limitation of medical facilities and/or personal financial conditions. Methods We conducted a non-randomized, single-dose, open-label investigator-initiated clinical trial (ChiCTR2200055565) in representative patients in southern China, including those with ferritin above 5000 µg/L. Among the 11 β-thalassemia major patients (aged 6-22) we enrolled, 6 of the patients were in poor clinical conditions (e.g., medium (3000-5000 µg/L ferritin) to severe (&amp;gt;5000 µg/L ferritin) iron overload) due to inconsistent blood transfusions and iron chelation therapy before enrollment (Table). We treated patients using their own HSCs after transduced ex vivo with KL003, a lentiviral vector expressing a functional β-globin gene. We then monitored patients closely for safety and evaluated efficacy of KL003, including stem cell engraftment, hematopoietic reconstitution/recovery, and blood transfusion requirement. Results Blood transfusion was no longer needed for all 11 patients from median day 14 (range: 10-30 days) after treatment. The longest duration of no blood transfusion has been 18 months. The median engraftment time was 14 days for neutrophils (range: 8-15 days) and 14 days (range: 11-33 days) for platelets. This is a significant improvement compared with much longer engraftment time from previous autologous HSC-based gene therapies in the literature, which were around 4 weeks for neutrophils and 6 weeks for platelets. It is worth noting that the platelet engraftment time (33 days) for patient No. 07, who had a severe iron overload, was much longer than others (Table). This may represent a common challenge for treating patients with severe iron overload. The safety profile was consistent with that typical of busulfan-based myeloablation conditioning. There were no severe adverse events associated with KL003. Conclusion Our clinical trial results demonstrate potentially curative results in β-thalassemia major patients, including those in poor clinical condition. In addition, the optimized transduction process of HSCs may have contributed to maintaining stemness of HSCs, which is essential for quick engraftment and often gets lost during ex vivo manipulation. This has led to significantly faster engraftment and better efficacy. Thus, KL003 could be a potential functional cure for β-thalassemia major patients.

Long-term clinical efficacy and safety of thalidomide in patients with transfusion-dependent β-thalassemia: results from Thal-Thalido study

Regular blood transfusion is the mainstay of treatment in transfusion-dependent β-thalassemia (TDT); however, transfusions culminate in an array of serious complications. Therefore, a single-arm, non-randomized clinical trial was conducted in hydroxyurea refractory TDT patients to explore the long-term safety and efficacy of thalidomide. The primary outcomes for efficacy were rise in hemoglobin (Hb) level and changes in transfusion frequency. Whereas, several clinical and laboratory parameters were assessed for safety of thalidomide. Secondary outcomes included changes in serum ferritin, serum lactate dehydrogenase (LDH), serum uric acid, red blood cell indices, and size of liver and spleen. A total of 532 patients were followed for a period of 30 months. Significant increase in mean Hb level was identified at 6 months (1.4 g/dL, p ≤ 0.001) and 30 months (2 g/dL, p ≤ 0.001) in comparison with baseline. A total of 408 (76.7%) patients responded to thalidomide therapy (excellent responders 25.8%, good responders 31%, and partial responders 19.9%) and attained transfusion independence within 6 months of therapy. A significant decline in mean ferritin, LDH level, liver size, and spleen size was observed. No unfavorable effects were observed on kidney and liver functions. Mild adverse events were reported in 48 (9%) patients and serious adverse events, including cerebral vascular accident and portal vein thrombosis were reported in two patients each. This study concludes that thalidomide is an effective and well-tolerated drug that can improve Hb levels and reduce transfusion burden in hydroxyurea refractory TDT patients.Trial registration: This trial is registered at http://www.clinicaltrial.gov as # NCT03651102.

Evidence that platelets from transfusion-dependent β-thalassemia patients induce T cell activation

A hypercoagulable state leading to increased risk for thrombotic events represents one of the most common complications observed in transfusion-dependent β-thalassemia (TDT) patients. TDT patients have increased frequencies of circulating activated platelets. However, there is no information so far if platelets from TDT patients can activate T cells. In the present study we showed that T cells treated with platelets from TDT patients showed significant increased surface expression of CD69 compared to the T cells treated with platelets from healthy individuals. Patients with splenectomy showed increased T cell activation compared to patients with intact spleen. No T cell activation was observed following incubation with plasma alone, nor with platelets from healthy subjects. The percentages of regulatory T cells (Tregs) were also examined. TDT patients showed statistically significant increased percentages of Tregs compared to healthy controls. Additionally, we observed a positive statistically significant correlation between the percentages of Tregs and the platelet-induced activated T cells in patients who were not treated with aspirin. TDT patients showed increased levels of sP-selectin, suPAR and GDF-15, molecules implicated in platelet activation. We show that platelets from TDT patients can activate T cells in vitro. This activation correlates with markers of platelet activation and increased numbers of Tregs, perhaps in an effort to eliminate immune dysregulation, conceivably secondary to platelet activation.

Real-world complication burden and disease management paradigms in transfusion-related β-thalassaemia in Greece: Results from ULYSSES, an epidemiological, multicentre, retrospective cross-sectional study.

Patients with transfusion-dependent beta (β)-thalassaemia experience a broad range of complications. ULYSSES, an epidemiological, multicentre, retrospective cross-sectional study, aimed to assess the prevalence and severity of treatment and disease complications, capture disease management and identify predictors of complications in patients with transfusion-dependent β-thalassaemia, treated in routine settings in Greece. Eligible patients were adults diagnosed with β-thalassaemia ≥12 months before enrolment and having received ≥6 red blood cell (RBC) units (excluding elective surgery) with no transfusion-free period ≥35 days in the 24weeks before enrolment. Primary data were collected at a single visit and through chart review. Between Oct 21, 2019, and Jun 15, 2020, 201 eligible patients [median (interquartile range, IQR) age 45.7 (40.2-50.5) years; 75.6%>40 years old; 64.2% female] were enrolled, a mean (standard deviation) of 42.9 (7.8) years after diagnosis. Median (IQR) age at diagnosis and RBC transfusion initiation were 0.8 (0.4-2.8) and 1.3 (1.0-5.0) years, respectively. From diagnosis to enrolment, patients had developed a median of six (range: 1-55) complications; 19.6% were grade ≥3. The most represented complications were endocrine/metabolic/nutrition disorders (91.5%), surgical/medical procedures (67.7%) and blood/lymphatic system disorders (64.7%). Real-world data generated by ULYSSES underscore the substantial complication burden of transfusion-dependent β-thalassaemia patients, routinely managed in Greece.

Red Blood Cell Alloimmunization and Autoimmunization in Blood Transfusion-Dependent Sickle Cell Disease and β-Thalassemia Patients in Al-Ahsa Region, Saudi Arabia.

The risk of developing transfusion-related complications, especially alloimmunization, is an ongoing concern for transfusion-dependent patients. It is important to determine the rate of alloimmunization and autoimmunization in Al-Ahsa Region, Saudi Arabia, where sickle cell disease (SCD) and thalassemia incidence rates are the highest in Saudi Arabia. A cross-sectional study was conducted to review the transfusion history of patients with SCD and thalassemia at the King Fahad Hospital (KFH) in Al-Ahsa, Saudi Arabia. 364 transfusion-dependent patients were included in this study. Alloimmunization rates in patients with SCD and thalassemia were 16.7% and 11.97%, respectively, while autoimmunization rates in patients with SCD and thalassemia were 5.3% and 0.7%, respectively. The most frequent alloantibodies among the study participants were against Kell, Rh blood group systems. Blood transfusion-related alloimmunization and autoimmunization compromise the proper management of chronically transfused patients. Ideally, extended matched phenotyping should be implemented to prevent alloimmunization and reduce the risk of developing blood transfusion-related alloantibodies.

Efficacy of Hydroxyurea in Transfusion-Dependent Major β-Thalassemia Patients: A Meta-Analysis.

The present meta-analysis was conducted to determine the efficacy of hydroxyurea in patients with transfusion dependent major β-thalassemia.The present meta-analysis was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Meta-analyses of Observational Studies in Epidemiology (MOOSE) guidelines.A systematic search was carried out to evaluate the efficacy of hydroxyurea in patients with transfusion-dependent B-thalassaemia using electronic databases, including MEDLINE, Cochrane Central Register of Controlled Trials, and EMBASE. The keywords used to search for relevant studies included "hydroxyurea", "thalassemia", "transfusion-dependent", and "efficacy".Outcomes assessed in the present meta-analysis included transfusion in one year and intervals between transfusions (in days). Other outcomes assessed in the present meta-analysis were fetal hemoglobin (%), hemoglobin (%), and ferritin levels (ng/dl). Total of five studies were included in the analysis enrolling 294 patients with major B-thalassemia.The pooled analysis reported that the mean interval between transfusions was significantly higher in patients receiving hydroxyurea compared to those not receiving hydroxyurea (mean deviation {MD}: 10.07, 95% CI: 2.16, 17.99).Hemoglobin was significantly higher in patients receiving hydroxyurea compared to its counterparts (MD: 1.71, 95% CI: 0.84, 2.57).Patients receiving hydroxyurea had significantly lower ferritin levels compared to those not receiving hydroxyurea (MD: -299.65, 95% CI: -518.35, -80.96).These findings suggest that hydroxyurea may be a promising and cost-effective alternative to blood transfusions and iron chelation therapies for beta-thalassemia patients. However, the authors noted that further randomized controlled trials are needed to validate these findings and to determine the optimal dosages and treatment regimens for hydroxyurea in this patient population.

Evaluation of conventional renal function tests in β-thalassemia major patients in Nineveh province

β-thalassemia is an inherited anemia, caused by impaired β-globin chain synthesis. The disease leads to serious health problems unless treated by regular blood transfusion and iron chelating therapy. However, complications from continuous therapy may arise due to iron overload and toxicity of iron chelating therapy, it may affects many organs in the body including the renal system. The present study was directed to study the changes in conventional renal function tests that may occur in β-thalassemia patients. The present study consisted of two groups of β-thalassemia patients; group A, 40 transfusion dependent β-thalassemia patients receiving only regular blood transfusion, age ranged 1-4 years; Group B, 40 transfusion dependent β- thalassemia patients receiving regular blood transfusion and deferroxamine chelation therapy, age ranged 4-20 years old. In addition to a control group C, 40 subjects, age ranged 1-20 years. Blood samples were collected and serum was separated for measurement of creatinine, urea, and ferritin. Urine samples were also collected for measurement of microalbuminuria. There was a significant decrease in serum creatinine, and a significant increase in serum urea in group B when compared with their control (P≤0.01). In addition, there was a significant increase in serum ferritin in groups A and B when compared with their controls (P≤0.01). On the other hand, there were no significant changes in microalbuminuria between groups A and B when compared with their controls. The results of the present study showed no deterioration in renal functions in β-thalassemia patients in both groups A and B regarding serum creatinine and urea in addition to microalbuminuria, although, subclinical alteration in renal functions could be expected in those patients, so that measurement of other early markers of renal dysfunction is occasionally recommended.

Polyneuropathy Associated with Age of Starting the Transfusion and Serum Ferritin Level in Iranian Patients with Thalassemia Major and Intermedia

Considering the importance of managing patients with β-thalassemia and the importance of early detection of disease complications, we examined the rate of sensorimotor neuropathy in patients with β-thalassemia and the risk factors related to it. This cross-sectional study included 44 blood transfusion-dependent β-thalassemia patients aged 5 years and older. Nerve conduction studies (NCSs) were performed via standard procedures for both motor and sensory nerves. Neuropathy was observed in 14 patients (31.8%). NCS results for sensorimotor nerves in patients were within normal range. In motor NCS results, increased ulnar nerve amplitude was observed in patients with increasing age, and peroneal nerve delay in patients with an increase in serum ferritin level (p < 0.05). In sensory NCS results, delayed ulnar and sural nerves latencies were found in patients with an increase in serum ferritin level (p < 0.05). We provide data that sensorimotor neuropathy exists in thalassemia patients. It seems that with the increase of serum ferritin level and the age of patients, neuropathy becomes more obvious, while other factors such as gender, body mass index, and the number of transfusions may not be associated with neuropathy.

Prevalence of hypogonadism in transfusion-dependent β-thalassemia patients of Bangladesh: investigating the role of serum ferritin level as a diagnostic tool

IntroductionHypogonadism is one of the most frequent complications in transfusion-dependent thalassemia patients and early recognition and treatment is the core element in restoring impaired gonadal function. Despite the high burden of disease, relevant studies are scarcely addressing the gonadal function of such patients in Bangladesh. The pattern of gonadal function in transfusion-dependent thalassemia patients must be characterized before planning a generalized management plan. Moreover, since iron overload is a key reason behind hypogonadism in thalassemia patients, investigating the role of serum ferritin level as a diagnostic tool for hypongadism was also an aim of this study. MethodsThis cross-sectional study was conducted at the Department of Transfusion Medicine of the Bangabandhu Sheikh Mujib Medical University. According to the inclusion and exclusion criteria, a total of 94 patients were enrolled in this study. A detailed history and thorough clinical examination were carried out in each patient and recorded using a pretested structured questionnaire. In addition, the laboratory assessment of serum ferritin, luteinizing hormone (LH), follicle stimulating hormone (FSH), testosterone and estradiol in serum were also performed. The data were analyzed using the STATA (v.16). ResultsThe mean age of the patients with transfusion-dependent thalassemia was 18.81 ± 4.65 (SD), with 53.3% of the patients being male. The overall prevalence of hypogonadism was 35.11%, 18.1% being normogonadotropic, 11.7% being hypogonadotropic and 5.3% being hypergonadotropic. The serum ferritin level was significantly higher (p < 0.001) in patients with hypogonadism (Eugonadal: 2,174.79 (± 749.12) ng/ml; Hypogonadal: 3,572.59 (± 1,199.49) ng/ml). The area under the receiver operating characteristic (ROC) curve of serum ferritin was high (0.83) and the p-value was highly significant (< 0.001). ConclusionTherefore, the serum ferritin level and gonadal hormone analysis of transfusion-dependent thalassemia patients can be considered a screening tool for assessing gonadal function and early detection and prevention of hypogonadism.

Optical coherence tomography findings in patients with transfusion-dependent β-thalassemia

BackgroundStructural ophthalmologic findings have been reported in patients with β-thalassemia due to chronic anemia, iron overload, and iron chelation therapy toxicity in few previous studies. We aimed to investigate structural ocular findings and their relationship with hematological parameters in patients with transfusion-dependent β-thalassemia (TDT).MethodsIn this cross-sectional study, from January 2018 to January 2019, 39 patients with TDT over the age of 18 participated. Multicolor fundus imaging, optical coherence tomography (OCT), and blue light fundus autofluorescence imaging were performed for all patients and 27 age- and sex-matched controls.ResultsThe mean age of patients was 28.6 ± 6.2 years. The central macular thickness and macular thicknesses in all quadrants were significantly thinner in patients than controls (P<0.05). None of the retinal nerve fiber layer (RNFL) measurements were significantly different between TDT patients and controls. There was a significantly negative correlation between hemoglobin with central macula thickness (r=-0.439, P=0.005). All measurements of macular subfield thickness were insignificantly thinner in patients with diabetes mellitus (DM) compared to the non-DM subgroup.ConclusionsMacular thickness was significantly thinner in central macula and entire quadrants in TDT patients compared to healthy individuals; however, all RNFL measurement thicknesses were comparable between the two groups. Close monitoring of TDT patients by periodic ophthalmologic examinations with more focus on diabetic patients, patients with severe anemia and iron overload should be warranted.

P1465: INITIAL SAFETY AND EFFICACY STUDY OF RM-001, AUTOLOGOUS HBG1/2 PROMOTER-MODIFIED CD34+ HEMATOPOIETIC STEM AND PROGENITOR CELLS, IN TRANSFUSION-DEPENDENT ΒETA-THALASSEMIA

Background: Natural mutations that cause hereditary persistence of fetal hemoglobin (HPFH) alleviate the symptoms of β-thalassemia. It is now known that small natural deletions and mutations in the γ- globin gene (HBG1/HBG2) promoters disrupt the binding of the transcriptional repressors BCL11A, causing HPFH. Using gene editing to mimic these mutations should reactivate γ- globin in patients with transfusion-dependent β-thalassemia (TDT) and ameliorate the debilitating effects of mutations in β-globin. Aims: To induce HbF production in erythrocytes, we used ex vivo CRISPR-Cas9–based gene editing to modify HBG1/HBG2 promoter in hematopoietic stem and progenitor cells (HSPCs), producing RM-001. We initiated initial safety and efficacy study of RM-001 in TDT patients. Here, we present initial results from the first 2 patients treated with RM-001. Methods: Patients (6–35 y of age) with TDT receiving packed red blood cell (pRBC) transfusions of ≥100 mL/kg/y or ≥10 units/y in the previous 2 y were eligible. Peripheral CD34+ HSPCs were collected by apheresis after mobilization with G-CSF and plerixafor. CD34+ cells were edited with CRISPR-Cas9 using a guide RNA specific for the binding site of BCL11A on the HBG1/HBG2 promoter. Prior to RM-001 DP infusion, patients received myeloablative conditioning with Busulfan from day-7 to day-3. Patients were monitored for stem cell engraftment/hematopoietic recovery, adverse events (AEs), Hb production, HbF and F-cell expression, pRBC transfusion requirements. Results: Data presented here for the first 2 TDT patients treated with RM-001. Both patients have β0/β0 genotype (CD17/CD41-42, CD41-42/CD41-42), with an annualized packed red blood cell (pRBC) transfusion history of 39 units/y and 54.8 units/y over 2 y prior to consent, respectively. Both patients received a single dose of RM-001 cells, ceased pRBC transfusions within 1 month after RM-001 infusion and remained transfusion-free through the reported period. The first patient (CD17/CD41-42, 9y) achieved neutrophil and platelet engraftment on Day(D+)19 and D+21; the other (CD41-42/CD41-42, 13y) achieved neutrophil and platelet engraftment on D+16 and D+21, respectively. No serious adverse event (SAE) occurred. The safety profile was generally consistent with busulfan myeloablation and autologous hematopoietic stem cell transplantation. Total Hb, HbF and F-cell percentage increased over time in both patients (Figure). Both patients received 6 units of pRBC before transfusion independent (TI) achieved (Hb stably ≥ 90g/L), with last pRBC transfusion on D+15 and D+28, respectively. The first patient achieved TI on D+28 and the other achieved TI on D+39. At 3 month post-RM-001 infusion, total Hb exceed 110 g/L in both patients, with 97-98 g/L HbF. Approximately 89% peripheral erythrocytes are F-cells at 3 month post-RM-001 infusion (Figure). Data will be updated for the presentation. Image:Summary/Conclusion: The first 2 patients treated with RM-001 demonstrated successful engraftment and both have been transfusion free within two month. Although both patients have β0/β0 genotype, they ceased pRBC transfusions within 1 month after RM-001 infusion and remained transfusion-free through the reported period. This is the first-in-human study of autologous HBG1/2 promoter-modified CD34+ HSPCs (RM-001) in TDT and both patients were treated successfully without SAE. Our studies provide novel and initial clinical evidence supporting the safety and efficacy of RM-001 for treating TDT.

The clinical characteristics, biochemical parameters and insulin response to oral glucose tolerance test (OGTT) in 25 transfusion dependent β-thalassemia (TDT) patients recently diagnosed with diabetes mellitus (DM).

Background:Patients with transfusion dependent β-thalassemia (TDT) are at high risk for developing, over the time, a form of diabetes distinct from type 1 and type 2 diabetes, but with similarities to both.Aims of study:The aim of this study is to describe the clinical and laboratory data, and the insulin secretion and sensitivity, in TDT patients recently diagnosed with diabetes mellitus (DM).Materials and Methods:The medical records of 25 TDT patients with DM, diagnosed by standardized oral glucose tolerance test (OGTT) and insulin secretion, were analysed; data were compared to TDT patients without diabetes and to a group of healthy subjects. Natural history of glucometabolic status before the diagnosis of DM was also reviewed.Results:On average, the TDT patients with DM were younger compared to TDT patients without diabetes. The mean age at diagnosis of DM in female and male TDT patients was 24.0 ± 7.1 years and 31.9 ± 5.6 years, respectively (P: 0.007). Serum alanine aminotransferase values, basal insulin levels and prevalence of hypogonadism were consistently higher in TDT patients with DM compared to those without diabetes. Decreased insulin secretion and increased insulin resistance was observed in patients with DM.Conclusion:The natural history of glucometabolic status in TDT patients is characterized by a deterioration of glucose tolerance over time. Iron overload and liver dysfuction are the main factors responsible for glucose disturbances (GD) in TDT patients. The therapeutic approach must be individualized and followed by a multidisciplinary team. (www.actabiomedica.it)

Prevalence of transfusion-transmitted infections in multiple blood transfusion-dependent thalassemic patients in Asia: A systemic review.

BackgroundThalassemia is a hereditary hemolytic anemia marked by a defect in synthesizing one or more globin chains in hemoglobin. In Pakistan, approximately 10,000 patients with thalassemia are primarily dependent on blood transfusions. The β-thalassemia patients require blood transfusions and iron chelation therapy. Patients who need blood transfusions are at an increased risk of contracting transfusion-transmitted infections (TTIs) such as hepatitis B and C viruses (HBV and HCV, respectively), as well as the human immunodeficiency virus (HIV).ObjectiveThis systemic review aims to assess the prevalence of TTIs in transfusion-dependent β-thalassemia patients in Asia.MethodsThe data for the systematic review were gathered from PubMed, Google Scholar, the Directory of Open Access Journals (DOAJ), and ScienceDirect using the following keywords: “prevalence, HBV, HCV, HIV, thalassemia, and transfusion-transmitted infections (TTIs)," and so on. This review includes the research articles that address the prevalence of viral infections in thalassemic patients following blood transfusion.ResultsA preliminary search of various databases identified 231 potential studies. 157 duplicate studies were eliminated, and the eligibility of 59 full-length articles was determined. Only 43 studies met the inclusion criteria. Among the 43 studies analyzed, 11 reported a high prevalence of HCV alone in thalassemic patients, while 21 reported a high prevalence of HCV and HBV infection in thalassemic patients. Eight studies reported the prevalence of all three TTIs examined, namely, HCV, HBV, and HIV, in patients with transfusion-dependent thalassemia.ConclusionPreventable transfusion-transmitted infections occur frequently, and robust national policies and hemovigilance are required to detect and mitigate the infection risk.