Molecular characteristics of hereditary red blood cell membrane disorders in Thailand: a multi-center registry.

Red blood cell (RBC) membrane disorders represent a significant category of hereditary hemolytic anemia; however, information from Southeast Asia is limited. We established a national registry aiming to characterize RBC membrane disorders and their molecular features in Thailand. A total of 100 patients (99 kindreds) diagnosed with RBC membrane disorders between 2011 and 2020 from seven university hospitals were enrolled. The most prevalent disorders observed were hereditary elliptocytosis (HE; n=33), hereditary pyropoikilocytosis (HPP; n=28), hereditary spherocytosis (HS; n=19), Southeast Asian ovalocytosis (SAO; n=10 of 9 kindreds), and two cases of homozygous SAO. The remaining cases were grouped as unclassified membrane disorder. Seventy-six patients (76%) were molecularly confirmed by PCR, direct DNA sequencing, or hi-throughput sequencing. The primary causative gene for HE and HPP was SPTB, accounting for 28 out of 29 studied alleles for HE and 56 of 56 studied alleles for HPP. In the case of HS, dominant sporadic mutations in the ANK1 gene (n=4) and SPTB gene (n=3) were identified as the underlying cause. Notably, the four most common variants causing HE and HPP were SPTB Providence (c.6055 T>C), SPTB Buffalo (c.6074 T>G), SPTB Chiang Mai (c.6224 A>G), and SPTB c.6171__82delins TGCCCAGCT. These recurrent SPTB mutations accounted for 79 out of 84 mutated SPTB alleles (94%). In summary, HE and hereditary HPP associated with recurrent SPTB mutations are the predominant types of RBC membrane disorders observed in Thailand. These findings have significant implications for the clinical management and future research of RBC membrane disorders in the region.

National strategic advocacy to manage patients with inherited bleeding disorders in low and lower-middle income countries.

INTRODUCTION: Inherited bleeding disorders (IBDs) including hemophilia, von Willebrand disease, platelet disorders, mucocutaneous bleeding disorders and coagulation factor deficiencies are rarely found and under-recognized in low and lower-middle-income countries. Some patients succumbed to serious bleeding without diagnosis and treatment during childhood. AREA COVERED: Diagnosis, management, and prevention should be integrated into the existing health care system. Although some countries have not implemented appropriate health care infrastructure, an initiative plan should be set up by cooperation of experienced experts and health care providers. Identification of patients with IBDs should be started in the antenatal setting to search for females at risk of carrier state. The investigations include bleeding assessment, mixing venous clotting time, coagulogram, coagulation factor assay and mutation detection. Genotypic analysis is helpful for confirming the definite diagnosis, carrier detection as well as prenatal diagnosis for females at risk of bearing an offspring with severe bleeding manifestations. Management involves replacement therapy ranging from blood component to virus-inactivated factor concentrate. Appropriate research is an essential backbone for improving patients' care. EXPERT OPINION: Effective national strategic advocacy to manage patients with IBDs requires intensive collaboration among policy makers, health care providers, patients, and family members.

Thalassemia-related complications in pediatric, adolescent, and young adult patients with transfusion-dependent thalassemia: A multicenter study in Thailand.

INTRODUCTION: Management of transfusion-dependent thalassemia (TDT) can be challenging due to numerous potential disease-related complications and comorbidities in particular age groups. The objective of this study was to report thalassemia-related complications and risk factors in pediatric, adolescent, and young adult patients with TDT. METHODS: A multicenter web-based registry was conducted in patients with TDT aged 25 years and younger from eight university hospitals covering all parts of Thailand. Factors significantly associated with each complication were analyzed by logistic regression methods. RESULTS: Of 605 patients, 267 thalassemia-related complications were reported from 231 pediatric, adolescent, and young adult patients with TDT patients (38.2%). The most common complications were infections, followed by cholelithiasis and growth failure. Splenectomy and elevated pre-transfusion hemoglobin were statistically significant risk factors for infections (adjusted odds ratio [AOR] = 2.3, 95% confidence interval [CI]: 1.2-4.5, p-value = .01 and AOR = 1.5, 95% CI: 1.2-1.7, p-value < .005, respectively). There were two statistically significant risk factors conferred endocrinopathies, including older age (AOR = 1.06, 95% CI: 1.01-1.1, p-value = .01) and being male (AOR = 2.4, 95% CI: 1.4-4.0, p-value = .002). CONCLUSION: Nearly 40% of the patients in this cohort had thalassemia-related complications. Periodic surveillance and optimal care for respective complications may minimize comorbidities in pediatric, adolescent, and young adult patients with TDT.

Practices and challenges for hemophilia management under resource constraints in Thailand.

Hemophilia is an inherited bleeding disorder caused by deficiency of a specific coagulation factor. Factor VIII deficiency is responsible for hemophilia A while factor IX deficiency is responsible for hemophilia B. As per the 2020 annual global survey by the World Federation of Hemophilia, only 1828 Thai hemophiliacs have been registered to the national healthcare system. The reason for the low number is the underdiagnosis which is a major concern in the real-world practice among Asian countries. In Thailand, most hemophiliacs are diagnosed by general practitioners, pediatricians or internists at rural hospitals and are referred to hemophilia specialists at the Hemophilia Treatment Centers (HTCs). Despite the challenges pertaining to infrastructure and cost of treatment, Thailand has progressed substantially in providing the required hemophilia care, as evidenced by an evolution in acquiring and sharing knowledge as well as collaborative efforts among multiple stakeholders over the past three decades. In this letter-to-the-editor, the authors have summarized the practices for and challenges faced with hemophilia management in Thailand.

Outcomes of Overt and Non-overt Disseminated Intravascular Coagulation Using the ISTH DIC Scoring System in Children: A Single-Center Study.

Background: Several disseminated intravascular coagulation (DIC) scoring systems are used for prognosticating the clinical outcomes of patients with DIC. However, research on children is scarce. Therefore, this study compared the clinical outcomes of overt and non-overt DIC using the International Society on Thrombosis and Hemostasis (ISTH) DIC scoring system. Methods: This retrospective study reviewed data on children aged one month to 15 years diagnosed with DIC between 2003 and 2014. Results: Of 244 patients, 179 (73.4%) had overt DIC, and 65 (26.6%) had non-overt DIC. The most common causes were infection (84.8%), tissue injury (7%), and malignancies (2.9%). The 28-day case fatality rate was significantly higher for overt than non-overt DIC (76% vs. 15.6%; P < 0.001). DIC scores were significantly associated with mortality (R2 = 0.89). Each clinical parameter (platelet count, prothrombin time, and fibrin degradation products) was associated with mortality (P = 0.01). On multivariable analysis, the factors associated with death were platelet counts ≤ 50 000 cells/mm3 (OR, 2.42; 95% CI, 1.08-5.42; P = 0.031); overt DIC score (OR, 7.62; 95% CI, 2.94-19.75; P < 0.001); renal dysfunction (OR, 2.92; 95% CI, 1.34-6.37; P = 0.007); shock (OR, 39.62; 95% CI, 4.99-314.84; P = 0.001); and acute respiratory distress syndrome (OR, 25.90; 95% CI, 3.12-214.80; P = 0.003). Conclusions: The 28-day case-fatality rate was significantly higher for patients with overt than non-overt DIC and concordant with ISTH scores. ISTH DIC scores can be used as a clinical predictor for DIC in children.

Red blood cell alloimmunization and other transfusion-related complications in patients with transfusion-dependent thalassemia: A multi-center study in Thailand.

BACKGROUND: Thalassemia is a common genetic disease in Southeast Asia. Red blood cell (RBC) transfusion is an essential treatment for severe forms of thalassemia. We performed a study to demonstrate RBC alloimmunization and other transfusion-related complications in patients with transfusion-dependent thalassemia (TDT). STUDY DESIGN AND METHODS: A multi-center web-based registry of TDT was conducted in eight medical centers across Thailand. Thalassemia information, transfusion therapy, and transfusion-related complications were collected. Factors associated with each complication were demonstrated using the logistic regression analysis. RESULTS: Of 1000 patients recruited for the study, 449 were males (44.9%). The mean age was 23.9 ± 15.4 years. The majority of patients, 738 (73.8%) had hemoglobin E/beta-thalassemia. In the study, 421 transfusion-related complications were reported from 357 patients (35.7%). Alloimmunization was the most common complication which was found in 156 patients (15.6%) with 284 positive antibody tests. The most frequent antibodies against RBC were anti-E (80/284, 28.2%) followed by anti-Mia (45/284, 15.8%) and anti-c (32/284, 11.3%). Age ≥3 years at initial blood transfusion, splenomegaly, higher frequencies, and volumes of transfusion were significant factors associated with alloimmunization. None of the patients had to terminate blood transfusion due to multiple alloantibodies. Other commonly seen complications were allergic reactions (130, 13.0%), autoimmune hemolytic anemia (70, 7.0%) and febrile non-hemolytic transfusion reaction (54, 5.4%). CONCLUSIONS: Transfusion-related complications, especially alloimmunization, were common among Thai patients with TDT. Extended RBC antigen-matching for the Rh system and Mia should be implemented to prevent the development of alloantibodies in multi-transfused patients.

Long-Term Effectiveness, Safety, and Tolerability of Twice-Daily Dosing with Deferasirox in Children with Transfusion-Dependent Thalassemias Unresponsive to Standard Once-Daily Dosing.

BACKGROUND: Patients with transfusion-dependent thalassemia (TDT) risk iron overload and require iron chelation therapy. Second-line therapy is warranted for patients demonstrating poor chelation responses. PATIENTS AND METHODS: We retrospectively studied the serum-ferritin (SF), and liver-iron-concentration (LIC) outcomes of patients with TDT treated with twice-daily dosing of deferasirox (TDD-DFX) > 24 months, after failing to respond to once-daily deferasirox (OD-DFX). RESULTS: We enrolled 22 OD-DFX nonresponders (14 males and eight females; median age, 9.2 [3-15.5] years). The median blood transfusion was 216 (206-277) ml/kg/year. The median TDD-DFX treatment period was 30 (24-35) months. Before initiating TDD-DFX, the median SF level was 2,486 (1,562-8,183) ng/ml, while the median LIC was 6.6 (3.2-19) mg/g dry wt. There were 18 TDD-DFX responders (81.8%) and 4 TDD-DFX nonresponders. The median SF-level change was -724 (-4,916 to 1,490) ng/mL. The median LIC change was -2.14 (-13.7 to 6.8) mg/g dry wt. The 1-year and 2-year SF levels and LICs were statistically significant (SF, P = 0.006/0.005; and LIC, 0.006/0.005, respectively). There were no treatment interruptions secondary to adverse events. In the follow-up of the TDD-DFX responder group, 11 of the 18 had a reduced dose, whereas the remaining seven continued with the same dose. CONCLUSIONS: TDD-DFX appears to be an alternative treatment approach for patients refractory to OD-DFX, with a favorable long-term safety profile. Further studies with larger groups and pharmacogenetic analyses of OD-DFX responders are warranted to determine the efficacy and safety profile of TDD-DFX.

Antifungal Prophylaxis with Posaconazole versus Fluconazole in Children with Neutropenia Following Allogeneic Hematopoietic Stem Cell Transplantation: Single Center Experience.

BACKGROUND: Invasive fungal diseases (IFDs) are common and contribute to mortality in patients undergoing hematopoietic stem cell transplantation (HSCT). The relative efficacies of posaconazole (POS) and fluconazole (FLU) as primary antifungal prophylaxes are uncertain. METHODS: A retrospective study was performed on children treated with allogeneic HSCT who received POS or FLU during the early neutropenic period. The efficacies, safety, and tolerabilities of the prophylaxes were compared. RESULTS: Data on 78 HSCT recipients were analyzed. Most had thalassemia (58%). Pre-engraftment, POS and FLU were administered to 41 and 37 cases, respectively. There were no proven cases of IFD. However, 2 POS cases and 1 FLU case had probable IFDs. The IFD incidences of the POS (5%) and FLU (3%) groups demonstrated no statistical difference (p = 0.620). Of the 75 surviving cases receiving FLU post-engraftment (including 39 cases previously given POS), 3 had proven IFDs whereas 3 had probable IFDs (total, 6 [8%]) within 1 year post-HSCT. No cases discontinued the prophylaxes due to drug intolerance. The common adverse events with POS and FLU were not significantly different. Only 19% of the patients achieved the therapeutic POS level, with a starting dose of 4 mg/kg thrice daily. CONCLUSION: POS and FLU demonstrate comparable levels of effectiveness, safety, and tolerability as IFD prophylaxes for neutropenic children treated with allogeneic HSCT. Determination of the optimum POS dose and duration requires larger studies.

Invasive Fungal Diseases in Children with Acute Leukemia and Severe Aplastic Anemia.

Although the outcomes of childhood leukemia and severe aplastic anemia (SAA) have improved, infectious complications are still the major concern. Particularly worrisome are invasive fungal diseases (IFDs), one of the most common causes of infectious-related deaths in patients with prolonged neutropenia. A retrospective study was conducted of IFDs in pediatric patients with newly diagnosed or relapsed acute leukemia, or with SAA, at Siriraj Hospital, Mahidol University, Thailand. There were 241 patients: 150 with acute lymphoblastic leukemia (ALL), 35 with acute myeloid leukemia (AML), 31 with relapsed leukemia, and 25 with SAA. Their median age was 5.4 years (range, 0.3-16.0 years). The overall IFD prevalence was 10.7%, with a breakdown in the ALL, AML, relapsed leukemia, and SAA patients of 8%, 11.4%, 19.3%, and 16%, respectively. Pulmonary IFD caused by invasive aspergillosis was the most common, accounting for 38.5% of all infection sites. Candidemia was present in 34.6% of the IFD patients; Candida tropicalis was the most common organism. The overall case-fatality rate was 38.5%, with the highest rate found in relapsed leukemia (75%). The incidences of IFDs in patients with relapsed leukemia and SAA who received fungal prophylaxis were significantly lower than in those who did not (P = N/A and 0.04, respectively). IFDs in Thai children with hematological diseases appeared to be prevalent, with a high fatality rate. The usage of antifungal prophylaxes should be considered for patients with SAA to prevent IFDs.

MYH9 disorder: Identification and a novel mutation in patients with macrothrombocytopenia.

The diagnosis of MYH9 disorder is guided by recognizing granulocyte Döhle body-like inclusion bodies and large/giant platelets in the peripheral blood smear. Immunofluorescence study of nonmuscle myosin heavy chain IIA is a sensitive screening method for diagnosis of MYH9 disorder. The diagnosis can then be confirmed by genetic analysis. A total of 67 patients with macrothrombocytopenia were included, of which 11 patients (16%), aged 4 months to 22 years, were ultimately diagnosed with MYH9 disorder. One novel mutation in exon 30 at c.4338T>C (p.F1446A) was detected. This mutation was associated with nonhematologic manifestations presenting in late adolescence with cataracts, hearing loss, and hematuria.

Clinical outcomes and prognosis of Thai retinoblastoma patients.

BACKGROUND: Retinoblastoma (RB) outcomes in Thailand are unfavorable compared to those of developed countries. This study aims to determine whether the clinical outcomes of patients with RB significantly improved after the implementation of new therapeutic approaches and which clinical factors affect survival and globe-saving outcomes. METHODS: The medical records of patients newly diagnosed with RB and treated at Siriraj Hospital between January 2005 and December 2018 were reviewed retrospectively. Clinical data, treatments, and outcomes were collected and analyzed. RESULTS: In 194 eyes (144 patients), leukocoria was the most common presenting feature (76.8%); 129 (66.5%) eyes were staged in group E of the International Classification of Intraocular Retinoblastoma. Of the 149 enucleated eyes, 35 had high-risk histopathological features, mostly choroidal invasion; 45 eyes (23.2%) could be salvaged. The 5-year overall survival rate was 90.3%, an improvement compared to the previous study. The 5-year enucleation-free survival rates of Groups A and B, C, D and E were 100%, 83.1%, 36.7% and 16.6% respectively. Factors associated with a lower survival rate were interval from symptom onset to diagnosis >3 months (hazard ratio (HR): 5.8: 95% confidence interval (CI): 1.637, 20.579) and buphthalmos (HR: 12.57: 95% CI: 3.936, 40.153). Factors associated with high-risk features were secondary glaucoma (HR: 11.016: 95% CI: 1.24, 98.10) and pseudohypopyon (HR: 14.110: 95% CI: 2.16, 92.05). CONCLUSIONS: Survival rates and globe-saving rates appear to have improved; however, advanced-stage presentation remains the major hindrance. Further studies with a larger cohort and longer follow-up are warranted.

Using of deferasirox and deferoxamine in refractory iron overload thalassemia.

BACKGROUND: Iron overload is a major complication of transfusion-dependent thalassemia (TDT) and requires iron chelation (IC) therapy. However, a combination therapy may be required for patients responding poorly to monotherapy. METHODS: Nine TDT patients previously treated with IC were enrolled; five patients were previously treated with deferasirox (DFX) twice daily. The dose of DFX was 20-40 mg/kg/day, while the dose of deferoxamine (DFO) was 18-40 mg/kg/day for 3-6 days/week. RESULTS: At the 6- and 12-month time points, six and eight patients demonstrated decreased serum ferritin levels, with median reductions of 707 ng/mL (range, 1,653-5,444 ng/mL) and 1,129 ng/mL (range, 1,781-7,725 ng/mL) compared to the baseline, respectively. Eight patients also had a reduced liver iron concentration (LIC), with a median reduction of 3.9 mg/g dry wt (range, 8.3-11.1 mg/g dry wt). Of the five patients treated with DFX twice daily, four responded to combination therapy. All responsive patients could finally stop DFO after the decline in LIC. Moreover, there were no treatment-related complications. CONCLUSION: The combination of DFX and DFO proved to be effective and without significant toxicities for TDT patients who had been unresponsive to standard IC therapy. Further studies with a larger cohort size and long-term follow-up are warranted to elucidate the efficacy of the combination.

Pediatric primary central nervous system tumors registry in Thailand under National Health Security Office schemes.

BACKGROUND: Few epidemiological studies of pediatric central nervous system (CNS) tumors have been performed using data from Southeast Asian national registries. Therefore, we aimed to examine data on CNS tumors from the first national childhood CNS tumor registry in Thailand. METHODS: Newly diagnosed children with benign and malignant primary CNS tumors from 20 nationwide hospitals were included. Two eras in the Thai registry were studied to compare national protocol effectiveness, including 2003-2005 (before establishment of a pediatric CNS tumor protocol) and 2011-2012 (post-establishment). RESULTS: The first study period had 300 patients with an incidence of 7.5/1,000,000 person-years and the second had 168 patients with an incidence of 13.24/1,000,000 person-years. The three most common tumors were gliomas, medulloblastoma/primitive neuroectodermal tumor (PNET), and germ cell tumors. The most common tumor site was the cerebellum, followed by the brainstem and pineal region. Five- and 10-year overall survival (OS) rates were 46.62% (95% confidence interval [CI] 40.85-52.18) and 41.78% (95% CI 36.11-47.34), respectively, for the first period. The second period had a 5-year OS of 64.75% (95% CI 56.70-71.68). OS rates for gliomas, germ cell tumors, medulloblastoma/PNET, and ependymomas were better in the second period than in the first period. CONCLUSIONS: The incidence of primary childhood CNS tumors in our study is lower compared with other reports. Improvement of OS in the second study period might be because of establishment of the Thai Pediatric Oncology Group, and national protocols for childhood CNS tumors.

Impact of splenectomy on outcomes of hematopoietic stem cell transplantation in pediatric patients with transfusion-dependent thalassemia.

BACKGROUND: The role of splenectomy prior to hematopoietic stem cell transplantation (HSCT) is controversial. Only few studies compared the outcomes of splenectomized and nonsplenectomized children with transfusion-dependent thalassemia (TDT) undergoing allogeneic HSCTs. METHODS: A retrospective analysis was undertaken on a transplantation cohort of TDT patients; August 1987-December 2014 to compare transplant outcomes between splenectomized and nonsplenectomized groups. RESULTS: Ninety-six transplants in 86 TDT patients were analyzed. Sixteen patients were splenectomized before HSCTs. The splenectomized patients were significantly older (8.0 ± 1.9 vs 4.7 ± 0.6 years; P = 0.001), had larger livers and spleens (P = 0.001), and had a significantly shorter neutrophil engraftment time (absolute neutrophil count > 500/mm3 ; 15.0 ± 2.3 vs 19.2 ± 1.3 days; P = 0.004). Graft rejection occurred in 13.8% of the nonsplenectomized group, but not among the splenectomized patients. Though the splenectomized group's mortality rate was higher (25.0% vs 8.8%), this was not statistically significant (P = 0.491). The main causes of death in both groups were severe infections. The five-year overall survival (OS) rate was better for the nonsplenectomized group (91.78% vs 75.00%; P = 0.06). CONCLUSIONS: Although splenectomies prior to HSCT for the TDT patients in our cohort were associated with faster neutrophil engraftments and lower rejection rates, they did not produce significantly better OS or affect the mortality. As the splenectomies did not provide any distinct advantages, this procedure should not be routinely performed as a pre-HSCT regimen for TDT patients with splenomegaly. Better pre-HSCT preparation for TDT patients, including early and adequate blood transfusions to avoid splenomegaly, is recommended.

Effect of NUDT15 on incidence of neutropenia in children with acute lymphoblastic leukemia.

BACKGROUND: 6-Mercaptopurine (6-MP) is considered the backbone of therapy in the maintenance phase of acute lymphoblastic leukemia (ALL). Gene polymorphisms involved in thiopurine degradation are predictors of toxicity in patients treated with 6-MP. We investigated the effects of nucleoside diphosphate linked moiety X (nudix) type motif 15 (NUDT15) polymorphism NUDT15c.415C>T on neutropenia incidence, dose adjustment for 6-MP, and survival rates in Thai children with ALL. METHODS: Children diagnosed with ALL who received 6-MP in the maintenance phase of treatment, in 2005-2016, were retrospectively enrolled. RESULTS: The subjects consisted of 102 patients (median age, 5.2 years; 58 boys). On genetic testing 78, 22, and two patients were normal (CC), heterozygous (CT), and homozygous (TT), respectively. The incidence of neutropenia at 3 months was significantly higher in the CT/TT than CC polymorphism groups (OR, 12; 95%CI: 3.781-38.085, P < 0.001). The mean dose of 6-MP at 3, 6, and 12 months was significantly lower in the CT/TT versus the CC group (P < 0.001). The 5 year overall survival (OS) rate for CC was 80.4%, and for CT/TT, 95.5% (P = 0.34). The 5 year event-free survival (EFS) for CC and CT/TT was 75.1% and 85.7%, respectively (P = 0.17). After adjusted risk classification, no significant differences were observed for OS or EFS between the CC and CT/TT groups. CONCLUSION: Patients harboring the CT/TT polymorphism of NUDT15 had a significantly higher incidence of neutropenia during the first 3 months of maintenance, resulting in significantly lower doses of 6-MP.

Outcomes of pediatric retinoblastoma treated with ICEV regimen: A single-center study.

Retinoblastoma is the most common intraocular malignancy in children. The aim of this study was to investigate the efficacy and toxicity of combination ifosfamide, carboplatin, etoposide, and vincristine (ICEV) in advanced-stage pediatric retinoblastoma [International Classification of Retinoblastoma (ICRB) group D or E], and in ICRB group C in the second eye in simultaneously treated bilateral retinoblastoma. The medical records of retinoblastoma patients treated with concurrent ICEV regimen and focal therapy were retrospectively reviewed. The ICEV treatment protocol was, as follows: ifosfamide 1800 mg/m2 on Days 1-3; MESNA 600 mg/m2 on Days 1-3; carboplatin 560 mg/m2 on Day 1; etoposide 150 mg/m2 on Days 1-3; and vincristine 1.5 mg/m2 on Day 1. Of 16 retinoblastoma patients, 13 had bilateral disease. Seven first eyes in bilateral disease that were enucleated prior to ICEV therapy were excluded. Twenty-two eyes were finally included (six group C, six group D, and ten group E). Median follow-up was 3.4 years, and the median number of ICEV courses was 7. Fifteen globes could be salvaged, 12 responded to ICEV (six group C, five group D, and one group E), and three unresponsive eyes could be salvaged with external beam radiation therapy (EBRT). Enucleation-free and relapse-free survival was 68.2 and 54.5%, respectively. The results of this study suggest ICEV as an alternative therapeutic approach for globe salvage in pediatric retinoblastoma, especially in ICRB groups C and D with manageable acute toxicity. Further study in larger cohort is needed to confirm the effectiveness of treatment.

Eltrombopag for children with chronic immune thrombocytopenia (PETIT2): a randomised, multicentre, placebo-controlled trial.

BACKGROUND: The thrombopoietin receptor agonist eltrombopag has been shown to be safe, tolerable, and effective for adults with chronic immune thrombocytopenia. We aimed to investigate the safety and efficacy of eltrombopag for children with chronic immune thrombocytopenia. METHODS: PETIT2 was a two part, randomised, multicentre, placebo-controlled study done at 38 centres in 12 countries (Argentina, Czech Republic, Germany, Hong Kong, Israel, Italy, Russia, Spain, Taiwan, Thailand, UK, and USA). Paediatric patients aged 1-17 years who had chronic immune thrombocytopenia and platelet counts less than 30 × 10(9) per L were randomly assigned (2:1) to receive eltrombopag or placebo. We stratified patients by age into three cohorts (patients aged 12-17 years, 6-11 years, and 1-5 years) before randomly entering them into a 13 week, double-blind period. Randomisation was done by the GlaxoSmithKline Registration and Medication Ordering System and both patients and study personnel were masked to treatment assignments. Patients who were allocated eltrombopag received tablets (except for those aged 1-5 years who received an oral suspension formulation) once per day for 13 weeks. Starting doses for patients aged 6-17 were based on bodyweight, and ethnic origin and ranged between 50 mg/day and 25 mg/day (starting dose for patients aged 1-5 years was 1·2 mg/kg/day or 0·8 mg/kg/day for east Asian patients). Patients who completed the double-blind period entered a 24 week open-label treatment period in which all patients received eltrombopag at either the starting dose (if they were formerly on placebo) or their established dose. The primary outcome was the proportion of patients achieving platelet counts of at least 50 × 10(9) per L in the absence of rescue therapy for 6 or more weeks from weeks 5 to 12 of the double-blind period. The intention-to-treat population included in the efficacy assessment consisted of all patients who were randomly assigned to one of the treatment groups, and the safety population included all patients who received at least one dose of study drug. This trial is registered with ClinicalTrials.gov, number NCT01520909. FINDINGS: Beginning in March 15, 2012, 92 patients were enrolled, and the trial was completed on Jan 2, 2014. 63 patients were assigned to receive eltrombopag and 29 were assigned to receive placebo. In the double-blind period, three patients discontinued treatment because of adverse events: two patients in the eltrombopag group withdrew because of increased liver aminotransferases and one in the placebo group withdrew because of abdominal haemorrhage. 25 (40%) patients who received eltrombopag compared with one (3%) patient who received placebo achieved the primary outcome of platelet counts of at least 50 × 10(9) per L for 6 of the last 8 weeks of the double-blind period (odds ratio 18·0, 95% CI, 2·3-140·9; p=0·0004). Responses were similar in all cohorts (eltrombopag vs placebo: 39% vs 10% for patients aged 12-17 years, 42% vs 0% for patients aged 6-11 years, and 36% vs 0% for patients aged 1-5 years). Proportionately fewer patients who received eltrombopag (23 [37%] of 63 patients) had WHO grades 1-4 bleeding at the end of the double-blind period than did those who received placebo (16 [55%] of 29 patients); grades 2-4 bleeding were similar (three [5%] patients who received eltrombopag vs two [7%] patients who received placebo). During the 24-week open-label treatment period, 70 [80%] of 87 patients achieved platelet counts of 50 × 10(9) per L or more at least once. Adverse events that occurred more frequently with eltrombopag than with placebo included nasopharyngitis (11 [17%] patients), rhinitis (10 [16%] patients), upper respiratory tract infection (7 [11%] patients), and cough (7 [11%] patients). Serious adverse events occurred in five (8%) patients who received eltrombopag and four (14%) who received placebo. Safety was consistent between the open-label and double-blind periods. No deaths, malignancies, or thromboses occurred during the trial. INTERPRETATION: Eltrombopag, which produced a sustained platelet response in 40% of patients with chronic immune thrombocytopenia, is a suitable therapeutic option for children with chronic symptomatic immune thrombocytopenia. We identified no new safety concerns and few patients discontinued treatment because of adverse events. FUNDING: GlaxoSmithKline.

Outcomes of thalassemia patients undergoing hematopoietic stem cell transplantation by using a standard myeloablative versus a novel reduced-toxicity conditioning regimen according to a new risk stratification.

Improving outcomes among class 3 thalassemia patients receiving allogeneic hematopoietic stem cell transplantations (HSCT) remains a challenge. Before HSCT, patients who were ≥ 7 years old and had a liver size ≥ 5 cm constitute what the Center for International Blood and Marrow Transplant Research defined as a very high-risk subset of a conventional high-risk class 3 group (here referred to as class 3 HR). We performed HSCT in 98 patients with related and unrelated donor stem cells. Seventy-six of the patients with age < 10 years received the more conventional myeloablative conditioning (MAC) regimen (cyclophosphamide, busulfan, ± fludarabine); the remaining 22 patients with age ≥ 10 years and hepatomegaly (class 3 HR), and in several instances additional comorbidity problems, underwent HSCT with a novel reduced-toxicity conditioning (RTC) regimen (fludarabine and busulfan). We then compared the outcomes between these 2 groups (MAC versus RTC). Event-free survival (86% versus 90%) and overall survival (95% versus 90%) were not significantly different between the respective groups; however, there was a higher incidence of serious treatment-related complications in the MAC group, and although we experienced 6 graft failures in the MAC group (8%), there were none in the RTC group. Based on these results, we suggest that (1) class 3 HR thalassemia patients can safely receive HSCT with our novel RTC regimen and achieve the same excellent outcome as low/standard-risk thalassemia patients who received the standard MAC regimen, and further, (2) that this novel RTC approach should be tested in the low/standard-risk patient population.