Introduction In children with severe acquired aplastic anemia, although matched sibling donor (MSD) hematopoietic stem cell transplant (HSCT) is standard of care. If it's not available then usually immune suppressive therapy (IST) is offered. But the success of IST at best is 50-70% and many children only achieve partial response and still have risk of developing clonal disorders or relapse in follow up. Recent data has shown upfront matched unrelated donor (MUD) HSCT can be as good an option as MSD. However, MUD is not easily available in the developing world due to lack of registries and Non-Caucasian population and multiple ethnicities. Recently, John Hopkins group showed in a series of 14 patients of severe aplastic anemia, refractory to initial therapy with IST, that haploidentical donor HSCT with post-transplant cyclophosphamide (PTCy) can be offered as a treatment with event free survival (EFS) and overall survival (OS) of 100%. In the developing world, due to lack of funds, usually the first chance at therapy is the best chance and most people can't afford further therapy after failure of IST. So, we offered upfront haploidentical HSCT with PTCy to 4 children with severe aplastic anemia and here we describe outcomes of the same. Methods After informed consent of the parents four children (median age- 4 years, range 2-11 years and male: female = 1:3)) underwent haploidentical HSCT with PTCy from a family donor. Conditioning was Rabbit ATG 1.5 mg/kg x 3 days (day-8 to day-6), Fludarabine 40 mg/m2 × 4 days (day-5 to -2), Cyclophosphamide 14.5 mg/kg x 2 days (day-5 & -4) and total body irradiation 2 Gy (day-1). Peripheral blood stem cell was the graft in all cases (median CD34 cell dose -9 million/kg; range-5 to 11 million/kg). Donor was father in 3 cases and mother in 1. GVHD prophylaxis was PTCy 50 mg/kg on day +3 & +4 and cyclosporine and MMF. Results All children were transplanted within 2-months from diagnosis of aplastic anemia. All four children engrafted (Neutrophil engraftment on median day+17; range-16-19 and platelet median engraftment on day+16; range12-27). All were fully donor on day+30, 60 and 100. Acute GVHD grade 1 was seen in 1 child. No chronic GVHD was seen. CMV reactivation was seen in 2 children. All are alive and disease free and GVHD free at median follow up of 1 year (range 6 month to 30 months). Two are off immune suppression whilst one is on tapering dose and one with 6 months follow up is still on immune suppression. Conclusion Upfront haploidentical HSCT with PTCy is safe and effective option for children with aplastic anemia lacking a matched donor.
Introduction CD19 directed chimeric antigen receptor T cell (CART19) therapy has shown remarkable activity in B cell lymphoma and acute lymphoblastic leukemia (ALL). With the emergence of therapeutic anti CD19 antibodies for the treatment of B cell malignancies, it remains to be elucidated whether such antibodies would interfere with the ability of CART19 to exert their antitumor effect in a subsequent therapy.Tafasitamab is an Fc enhanced humanized anti CD19 monoclonal antibody which mediates antibody dependent cellular toxicity (ADCC), antibody dependent cellular phagocytosis and direct cytotoxicity. It is currently being studied in phase 2/3 clinical trials in diffuse large B cell lymphoma (DLBCL) in combination with lenalidomide and bendamustine. Objectives To investigate the potential for functional interference between tafasitamab and CART19. Methods CART19 cells were generated through lentiviral transduction of healthy donor T cells with a second generation CD19 CAR construct (FMC63-CD8h-CD8TM-41BBζ). In vitro functional activity of tafasitamab was assessed through killing assays against CD19+ cell lines, JEKO (mantel cell lymphoma), Ly7 (DLBCL) and NALM6 (ALL). To study whether the observed CART19 activity may be influenced by tafasitamab in case of a direct CD19 binding competition we incubated NALM6 or JEKO with up to 100 μg/ml tafasitamab, to saturate the receptors, and then performed flow cytometry using FMC63 anti CD19 antibody (it carries the same CD19 binding domain as CAR19). To investigate the potential impact of such binding competition on CART19 cell effector functions, we cocultured tafasitamab with JEKO at increasing concentrations of up to 100 μg/ml, and then added CART19 at different effector to target (E:T) ratios to the cell culture. Results In a 24 hours ADCC (Fig 1A) and T cell cytotoxicity assays (CART19, E:T titrations) distinct activity was observed for both therapies on all tested cell lines. Secondly, after testing the CD19 binding competition, FMC63 antibody failed to detect CD19 expression, indicating a direct binding competition between FMC63 and tafasitamab (Fig 1B). Next, after coculturing tafasitamab and CART19 in JEKO, it was evident that the presence of tafasitamab, binding to the CD19 antigen, did not affect important CART cell effector functions such as antigen specific killing (Fig 1C), degranulation (Fig 1D), cytokine production or proliferation of CART19 (Fig 1E). Conclusions Our studies indicate that CART19 cells continue to exhibit potent antigen specific effector functions despite presence of tafasitamab and the related competition for CD19 binding. The question of therapeutic sequencing of tafasitamab and CART19 is being studied in xenograft models.
Rationale Chronic granulomatous disease (CGD) is a primary immune deficiency due to defects in the phagocyte oxidative burst leading to life-threatening infections and inflammatory disorders. Due to high mortality and morbidity, hematopoietic cell transplantation (HCT) is now considered a potentially curative option. We evaluated outcomes of HCT at our institution over 13 years. Methods Retrospective chart review of CGD HCTs performed at John Hopkins All Children's Hospital between August 2005-October 2018. Results Eight patients (median age=2.2 years, range=1.1-4.3 years) with CGD underwent HCT: 6 patients had X-linked (CYBB, gp91phox), 2 patients had autosomal recessive (CYBA, p22phox). Pre-HCT infections were controlled including; pneumonia (n=3, 2 Aspergillus, 2 requiring lobectomy) and staphylococcal lymphadenitis/skin abscesses(n=3). Five of eight (62%) had inflammatory disease pre-HCT: lung granulomas (n=2), autoimmune hepatitis (n=3), and colitis (n=2).Myeloablative conditioning was used in 3 and reduced intensity/toxicity (RIC) in 5. Four received matched related donor and 4 received matched unrelated-donor HCTs. Median neutrophil engraftment was 18.5 days (range=10-21 days). Overall survival was 87.5%. One patient died (day +21) from disseminated Trichosporon. All patients achieved primary engraftment; 42% (3/7) maintained full donor chimerism (≥99%) with normalization of DHR, median follow-up 4.3 years (range=4-8.3 years); 42% (3/7) are mixed chimera (58-84% myeloid donor), median follow-up of 0.9 years (range=0.8-1.2 years).One patient who received RIC (Fludarabine/Melphalan/Campath) had secondary graft failure 1 year after HCT, has since developed inflammatory colitis, uveitis, and pneumonitis and is awaiting second HCT. There was no grade III-IV GVHD; 2 had acute grade I GVHD. Post-HCT complications included EBV viremia (without PTLD) in 1, pericarditis in 1, autoimmune cytopenias in 1 and hypothyroidism in 1. Conclusions Patients with CGD are at high risk of early mortality. HCT is a viable treatment option but has considerable risk, often deterring providers and patients from pursuing HCT early. Our institution's experience shows safety and efficacy with early HCT approach.
Background As the workload for completing CIBMTR forms continues to increase, the resources required to complete them has not increased at the same pace. While CPI goals are met at the University of Maryland Marlene and Stewart Greenebaum Comprehensive Cancer Center (UMGCCC), because of resource limitations, achieving CPI is a constant struggle. When CIBMTR announced that the completion of Cellular Therapy forms were highly recommended, how to accurately and timely completion of CPI forms has become our top priority. Method The simplest solution to the problem would be to add resources by hiring an additional Data Manager. However, with the scarcity of knowledgeable resources available, hiring and training a new Data Manager is a challenge. Therefore, with the number of Data Managers at our center, we identified the following strategies to implement to maximize time and effort while maintaining quality and accuracy in completing CIBMTR forms. The first thing we identified was to extract from FormsNet 3 all the forms due for the current CPI period into an excel spreadsheet, and divided the workload up by transplant type. Next, we determined how many forms each Data Manager needed to complete per day to be able to achieve CPI for the reporting period. To ensure we achieved our set goal, we created measures to evaluate progress of form completion. Data Managers provide a biweekly report to the manager, summarizing what was accomplished in the prior two weeks. From the report, Data Managers can determine whether or not they accomplish their set goals and modify accordingly. Furthermore, CIBMTR provides a CPI summary sheet to each center on a weekly basis indicating the current CPI completion percentage with a tool that identifies progress toward CPI goals. In addition, to assist in verifying data accuracy, the Data Managers incorporated internal assessments between Data Managers as well as meeting with primary physicians to discuss and confirm that certain complex data was accurately reported to CIBMTR. Result CPI requirements were met, however, real-time reporting on patients receiving transplant and cell therapy has not been possible. Conclusion While CPI reporting requirements are met, we anticipate that by developing realistic, achievable methods to 1) increase the number of forms completed per day; 2) create a tool to accurately determine the number of forms and which forms are coming due in real time; and 3) create a schedule of additional tasks required of the Data Manager, forms will be completed as transplant and cell therapies are being conducted.
Introduction Cellular immunotherapy is a rapidly progressing field in multiple myeloma (MM). Multiple clinical trials have reported impressive efficacy of B cell maturation antigen (BCMA) directed chimeric antigen receptor cell therapy (BCMA CART) in MM. While trials demonstrated a high response rate, the durable response rate is around 30%. Most patients lose their CART cells, and the disease relapses within the first year, suggesting an inhibition by the MM tumor microenvironment (TME). Therefore strategies to overcome this inhibition would represent a major advance in this field. Cancer associated fibroblasts (CAFs) within the TME play a critical role in promoting tumor growth and immunosuppression. Objective CAFs from MM patients lead BCMA CART cell dysfunction and targeting both MM cells and CAFs can overcome this resistance. Methods CAFs were isolated from the bone marrow (BM) of MM patients and purified using anti fibroblast beads. MM-TME mouse model was established by injecting a 1:1 ratio of BCMA+ OPM2 (MM cell line) to CAFs. Five different CART cells were tested in this study. For single transduced CAR: BCMA, CS1, and fibroblast activation protein (FAP). For dual transduced CAR: BCMA-CS1 and BCMA-FAP CART. These were generated through the double transduction of two lentiviral vectors. Results BCMA CART cell proliferation assay showed inhibition of CART expansion in the presence of CAFs, and this was mediated by TGF-β (Fig A). MM-TME mouse model revealed a significant acceleration of MM progression (Fig B). To identify targets, we verified FAP expression on CAFs. Interestingly, there was a low level of CS1, but not BCMA expressed on CAFs (Fig C).Then, we evaluated the impact of CAFs on functions of BCMA CART cells compared to dual CART cells. When CART cells were stimulated with the BCMA+ MM cell line MM1S, in the presence of CAFs, the proliferation of BCMA CART cells, but not the dual CART cells was significantly inhibited (Fig A). Similarly, in the presence of CAFs, the production of key effector cytokines by BCMA CART cells, but not the dual CART cells was reduced (Fig D).Finally, we studied the impact of CAFs on CART cell functions in vivo. First, using OPM2 xenografts, treatment with BCMA CART cells was able to eradicate MM (Fig E). Then, the MM-TME model was used to assess the effect of targeting CAFs. Mice were treated with 1) control T cells, 2) BCMA CART cells, 3) BCMA-FAP CART cells, or 4) BCMA-CS1 CART cells. A low dose (1 × 106 iv) of CART cell was used to induce relapse. BCMA CART cells led to a transient antitumor activity in this model (mice died within 2 weeks), while dual CART cells resulted in durable remissions, a higher number of circulating T cells, and long term survival (Fig F). Conclusion We demonstrate for the first time that dual targeting both malignant plasma cells and the CAFs within the TME is a novel strategy to overcome resistance to CART cell therapy in MM.
Introduction The treatment of patients with multiple myeloma (MM) has evolved in recent years, and the disease-associated prognosis has improved substantially. This improvement has been driven largely by the approval of novel agents, many of which are expensive and not universally available. Objective Evaluate the efficacy of treatment alternatives for multiple myeloma in a private center in México. Patients and methods All consecutive MM patients diagnosed after 1993 were retrospectively reviewed. Patients were given oral thalidomide (T), 100 mg/day, oral dexamethasone (D) (36-40 mg/week) and aspirin 100 mg/day. Bortezomib (V) (1.75 mg subcutaneously every week) was administered to those who could afford it. After 4-6 weeks of treatment, patients were offered an outpatient-based hematopoietic cell transplant (HCT). After the recovery of granulocytes following the HCT, patients continued indefinitely on T; those who failed to tolerate were switched to lenalidomide (R) (25 mg/day). The assessment of overall survival (OS) for all groups was achieved through the Kaplan-Meier method using the Cox-Mantel test. All the statistical analyses used a p value <0.05 to considered them statistically significant. Results Among 108 patients with MM who were prospectively accrued in the study (47 females and 61 males), the median age was 57 years (range 33 to 90). IgG myeloma represented 60% of patients and 49% had International Scoring System (ISS) stage III disease. The median (OS for all patients has not been reached and is >157 months. The median OS of patients who did not receive HCT was similar to those who did, with a trend for better outcomes with HCT (A). The response rate (complete remission or very good partial remission) was 71.8% for those given TD versus 88.3% for those given VTD before HCT, but OS was not different (B, C and D). As post-HCT maintenance, 37 patients received T; 26 of those (70%) could be maintained indefinitely with T, whereas 11 were switched into R after a median of 7 months; median OS of patients maintained after HCT with T or R was not different. Comparing the current population data with those obtained between 1983 and 1993 in the same institution employing only MP, the prognosis of MM patients was noted to have improved substantially. In our previous experience in the same institution, the median OS of patients treated solely with MP was 33 months, with a 72-month survival of 30%, whereas in this study of patients given IMiDs +/- HCT, median OS has not been reached and the 72-month OS is 60%, twice that obtained with MP. When analyzing the OS of patients included in this study and separated by 5-year intervals, survival continued to improve since 1993. Conclusions In this series, a regimen incorporating low cost novel agents and outpatient HCT was associated with excellent long-term survival in the treatment of persons with MM. This approach may be a model for treatment of MM in middle-income countries.
Introduction The erythropoietic porphyrias, congenital erythropoietic porphyria (CEP) and erythropoietic protoporphyria (EPP), are classified by the production and accumulation of heme pathway intermediates in the bone marrow. Cutaneous, hematopoietic and hepatic manifestations can be debilitating and require regular red blood cell transfusion and even liver transplantation. Hematopoietic stem cell transplant (HSCT) is the only curative treatment for these rare diseases. We present our single institution experience with HSCT for porphyrias. Objectives Report outcomes of HSCT for pediatric patients with porphyria using both myeloablative (MAC) and reduced intensity conditioning (RIC) regimens Methods Retrospective chart review Results A total of 5 patients underwent HSCT at our institution from 1999-2018 for erythropoietic porphyrias, 4 of whom had CEP and 1 who had EPP. Four patients with CEP had a median age of 1.93 years (range, 0.64-18.12 years) at time of transplant and underwent MAC with busulfan and cyclophosphamide +/- fludarabine. One patient with EPP, who had undergone liver transplant, had a RIC regimen with precision dosed alemtuzumab, fludarabine, and melphalan (Table 1). One patient died of infectious complications at day +45, while the remainder are alive without porphyria symptomology and with full donor chimerism. Special light filters and LED bulbs minimized the patients’ exposure to harmful light wavelengths while hospitalized. Discussion HSCT effectively corrects the defective bone marrow heme pathway in patients with erythropoietic porphyrias. HSCT should be considered in patients with severe manifestations and used early to minimize end-organ damage, particularly to the liver. RIC regimens can be used safely in patients with existing comorbidities to minimize toxicity without negatively affecting engraftment and survival.
Introduction The only curative treatment for severe aplastic anemia in children is allogenic stem cell transplantation, but only few patients have a matched related or unrelated donor. Haploidentical stem cell transplantation (haplo-SCT) using bone marrow (BM) and peripheral blood stem cells (PBSC) has been recently described as effective and safe. In this study, we retrospectively describe the outcome of nine pediatric patients who underwent haplo-SCT using only PBSC. Patients and methods The father was the selected donor for seven of the nine patients. Donor specific anti-HLA antibodies were ruled out. Stem cells mobilization was performed with filgrastim 10 mcg/kg/d for five days, and CD34+ were recollected by peripheral blood apheresis on day 0. The conditioning regimen consisted on rabbit anti-thymocyte globulin 2.5 mg/kg/d on days -7, -6, -5, and -4, and cyclophosphamide 50 mg/kg/d on days -3 and -2. We used cyclophosphamide 50 mg/kg/d on days +3 and +4, tacrolimus and mycophenolic acid as graft versus host disease prophylaxis. Results The median follow up was 253 days (range 45-765 days). The median infused CD34+ was 10 × 10^6/kg (range 2.7 to 43 × 10^6/kg). The median myeloid engraftment was day +15 (range 11-30 days), and median platelet engraftment was day +16 (range 12-30 days). In eight of the nine patients, a sustained graft was achieved. One patient never achieved platelet engraftment and died because of cytomegalovirus infection. There was not treatment related toxicity reported. None of the patients had GVHD. The overall survival up to date is 88.8%. The eight surviving patients remain free of transfusions. Conclusions Haplo-SCT could be established as first line treatment when there is no matched related or unrelated donor. According to this short sample and previous reports, PBSC is a feasible option to be effectively used as only source of stem cells.
Background Autologous hematopoietic cell transplantation (AHCT) followed by maintenance therapy is the current standard of care in the treatment of multiple myeloma (MM). Lenalidomide (Len) is most commonly utilized as maintenance therapy as it has been shown to improve both progression free survival (PFS) and overall survival (OS). However, long-term maintenance therapy with Len is associated with development of secondary primary malignancies (SPM). Proteasome-inhibitor (PI)-based maintenance strategies have been evaluated in several phase III trials and also appear to yield survival benefits in MM. Methods We performed a comprehensive search of the medical literature using PubMed/Medline and EMBASE on September 11, 2019. We extracted data on clinical outcomes related to benefits (OS, PFS and deepening of hematologic response [DOHR]) and harms (SPM), independently by two authors. Our search strategy identified total of 2144 references. Three studies (5 manuscripts) were included in this systematic review (Figure 1). Results Median age for patients receiving PI maintenance after AHCT ranged from 25 to 65 years. All patients underwent an AHCT with melphalan 200mg/m2 prior to initiation of PI maintenance. Also, 70% of patients received a PI-containing induction regimen. 513 patients received bortezomib maintenance and 395 patients received ixazomib. The control arm in these studies was either placebo (n=261) or thalidomide (n=597). PI maintenance did not improve OS (n=2 studies, 1012 patients, hazard ratio [HR] 0.88, 95% CI 0.73-0.105, p=0.15) but improved PFS (HR 0.75, 95% CI 0.67-0.85, p= <0.00001) compared to placebo/non-PI maintenance (Figure 2). PI maintenance led to a significant improvement in DOHR (HR 0.86, 95% CI 0.81-0.92, p=<0.0001) compared to placebo/non-PI maintenance. There were no significant differences between PI-maintenance and placebo/non-PI maintenance with regards to development of SPM (HR 0.98, 95% CI 0.65-1.47, p=0.90) (Figure 3). Conclusions The results of our systematic review show that PI-based maintenance following AHCT in MM leads to significant improvement in PFS and DOHR without an increase in development of SPM compared to placebo/non-PI maintenance. Prospective randomized phase III trials comparing Len to PI-based maintenance is an interesting question that remains unanswered.
