Frontline Chemotherapy Regimens Research Articles

Economic Burden Associated with Switching to Second Line Asparaginase (Recombinant Erwinia) in Pediatrics, Adolescents and Young Adults (AYA) with Acute Lymphoblastic Leukemia (ALL)

Background: Long-acting asparaginases derived from E. coli (pegaspargase [PEG] and calaspargase pegol [CAL-PEG]) are critical components of frontline (1L) chemotherapy regimens in pediatrics, adolescents and young adults (AYA) with acute lymphoblastic leukemia (ALL). In the event of ≥grade 3 hypersensitivity reactions based on CTCAE version 5.0, to an E. coli asparaginase, patients often switch to second line (2L) asparaginase derived from Erwinia (Recombinant Erwinia), which has an increased dosing of thrice/week due to its shorter half-life. Infusion reactions may masquerade as hypersensitivity reactions, leading to unnecessary formulation switches and potentially increased economic and healthcare burdens on patients and the healthcare system. Formulation switches may be mitigated through therapeutic drug monitoring (TDM) utilization which may help differentiate between neutralizing and non-neutralizing antibody-mediated reactions through quantification of serum asparaginase activity levels. This study aims to quantify the costs and healthcare resource utilization (HRU) associated with switching from 1L to 2L asparaginases in pediatrics and AYA patients with ALL, overall and by use of TDM. Methods: This is a retrospective study using Optum's deidentified Clinformatics® data mart. Pediatric/AYA patients (<40 years) diagnosed with ALL between Jan. 2021 and Sep. 2023 and treated with frontline asparaginase-containing regimen were identified throughout the US. Treatment start date was designated as the index date. Descriptive analyses were used to assess baseline demographics in the pre-index period, and use of premedication, TDM and proportion of switchers to recombinant Erwinia in the follow-up (post-index) period. Annualized mean HRU and costs were compared in the follow-up period between switchers and non-switchers, and by use of TDM in terms of inpatient admissions, outpatient visits, emergency department (ED) visits, and medical and prescription drugs. Among switchers, HRU and costs were also compared pre- and post-switching. Costs were adjusted and inflated to 2023 dollars. Results: A total of 154 pediatric or AYA patients with ALL were identified, of which 116 received PEG and 38 received CAL-PEG. Median (IQR) age was 8 (6-15) years. No patient >22 years received CAL-PEG, while 11% of patients receiving PEG were >22 years old. Nearly two-third were male. Median (IQR) follow-up duration was 11.3 (6-19.4) months. Approximately 58% of patients were given premedication- all on the same day as PEG/CAL-PEG infusion; 40% had TDM performed, 25% had both and 29% had none. Overall, 35 of 154 patients (23%) switched to recombinant Erwinia; including 21% of those on PEG and 29% of those on CAL-PEG. Switchers had a significantly higher mean outpatient visits per year compared to non-switchers (83 vs. 72; p=0.0466). This was mainly driven by the increased visits associated with recombinant Erwinia administration vs PEG/CAL-PEG administration (mean # of visits: 18 vs. 3, respectively; p<0.0001). Mean total healthcare costs were three times higher in switchers than non-switchers ($1,272,846 vs. $467,773; p<0.0001). This was mainly driven by outpatient costs which were nearly four times higher in switchers than non-switchers ($1,094,941 vs. $286,243). ED costs were higher for switchers ($11,960 vs $8,930), while outpatient prescription costs were lower ($5,273 vs $9,416) (all p<0.0001). No significant differences were found for inpatient costs. Among switchers, the outpatient costs were higher post-switching compared to pre-switching ($1,130,975 vs. $528,237; p<0.0001) further suggesting that the majority of the higher costs in the switchers was driven by administration of recombinant Erwinia. When compared by use of TDM, 28% switched to recombinant Erwinia in the non-TDM group and 14.8% in the TDM group. Mean outpatient costs were $511,810 and $384,396 (p<0.0001) in the non-TDM and TDM groups, respectively. Conclusions: Switch from 1L asparaginase to 2L recombinant Erwinia is relatively common in pediatric and AYA ALL patients which significantly increases treatment costs and HRU, mainly driven by higher outpatient medical costs of recombinant Erwinia. Consideration should be given to performing TDM which may have important implications for mitigating unnecessary switches as well as reducing healthcare burden and achieving substantial cost savings for payers.

The evolving role of checkpoint inhibitors in the treatment of Hodgkin lymphoma.

Since their initial approval as single agent therapy for multiply relapsed/refractory Hodgkin lymphoma (HL), the PD-1 inhibitors nivolumab and pembrolizumab have been incorporated into second-line salvage regimens, and they are being investigated in upfront therapy of newly diagnosed patients. As second-line therapy in combination with brentuximab vedotin or multi-agent chemotherapy, nivolumab and pembrolizumab provide high complete remission rates and durable progression-free survival after consolidative autologous stem cell transplant. Incorporation of these agents into frontline chemotherapy regimens is feasible, and early results from a Phase III trial of nivolumab-AVD compare favorably with the existing standard for advanced stage HL, brentuximab vedotin plus AVD. As nivolumab and pembrolizumab move into earlier lines of HL therapy, open research questions include the efficacy of checkpoint inhibitor regimens in patients who relapse after frontline exposure to nivolumab or pembrolizumab; the selection of patients with relapsed HL who can achieve durable remissions without autologous stem cell transplant; and the efficacy of the PD-1 inhibitors in the frontline therapy of patients with early stage Hodgkin lymphoma.

Protocol-Stipulated Dose Modification to Manage Chemotherapy-Induced Peripheral Neuropathy in Children, Adolescents, and Young Adults With High-Risk Hodgkin Lymphoma.

Brentuximab vedotin (BV) incorporation into frontline chemotherapy regimens improved outcomes for classic Hodgkin lymphoma (cHL). The shared mechanism of action of BV and vinca alkaloids as microtubulin inhibitors increased the potential risk of chemotherapy-induced peripheral neuropathy (CIPN). Rates of CIPN and use of protocol-stipulated dose modifications of a microtubulin inhibitor were examined on the Children's Oncology Group AHOD1331 study, which compared BV, doxorubicin, vincristine (VCR), etoposide, prednisone, cyclophosphamide (BV-AVE-PC; BV arm) with bleomycin containing doxorubicin, bleomycin, vincristine, etoposide, prednisone, cyclophosphamide (ABVE-PC; standard arm) in patients with high-risk cHL ages 2-21 years. AHOD1331 required clinician grading and reporting of ≥grade 2 CIPN. Protocol-stipulated dose modifications of VCR preceded modification of BV for ≥grade 2 CIPN in the BV arm, but only required modification of VCR for ≥grade 3 in the standard arm. Outcomes included CIPN rates, dose modification of microtubulin inhibitors by study arm, clinical factors associated with dose modifications, and event-free survival (EFS) by the presence of dose modification. Among the 582 patients who began protocol therapy, 112 developed ≥grade 2 CIPN. Cumulative incidence of CIPN did not differ by study arm (19.2 v 19.8%, P = .91). CIPN dose modifications occurred more frequently in the BV arm (9.5% v 2.8%, P = .001); however, most patients with CIPN on the BV arm received full-dose BV. EFS did not differ by the presence of dose modifications after accounting for study arm, age, sex, and stage, although older age was significantly associated with the risk of VCR dose modifications for CIPN. A staged dose modification plan for vinca alkaloids and BV as administered in AHOD1331 minimized the effect of incorporating a second microtubulin inhibitor on CIPN without compromising treatment efficacy in the BV arm.

Advances in Hodgkin Lymphoma Treatment: From Molecular Biology to Clinical Practice.

Classical Hodgkin Lymphoma (cHL) is a highly curable disease, but around 20% of patients experience progression or relapse after standard frontline chemotherapy regimens. Salvage regimens followed by autologous stem cell transplants represent the historical treatment approach for these cases. In the last decade, with the increasing understanding of cHL biology and tumor microenvironment role in disease course, novel molecules have been introduced in clinical practice, improving outcomes in the relapsed/refractory setting. The anti-CD30 antibody-drug conjugated brentuximab vedotin and PD-1/PD-L1 checkpoint inhibitors represent nowadays curative options for chemorefractory patients, and randomized trials recently demonstrated their efficacy in frontline immune-chemo-combined modalities. Several drugs able to modulate the patients' T-lymphocytes and NK cell activity are under development, as well as many anti-CD30 chimeric antigen receptor T-cell products. Multiple tumor aberrant epigenetic mechanisms are being investigated as targets for antineoplastic compounds such as histone deacetylase inhibitors and hypomethylating agents. Moreover, JAK2 inhibition combined with anti-PD1 blockade revealed a potential complementary therapeutic pathway in cHL. In this review, we will summarize recent findings on cHL biology and novel treatment options clinically available, as well as promising future perspectives in the field.

Clinical characteristics and outcomes of adult alveolar rhabdomyosarcoma patients on first-line systemic therapies: A single-institution cohort.

Background: Rhabdomyosarcomas are the most common soft tissue sarcoma in children, and pediatric alveolar rhabdomyosarcoma (ARMS) prognosis has improved based on cooperative studies. However, in adults, ARMS is significantly rarer, has poorer outcomes, and currently lacks optimal treatment strategies. Objective: This study aimed to evaluate the clinical outcome of an adult ARMS population with different front-line systemic chemotherapies and determine if any chemotherapy regimen is associated with improved survival. Materials and methods: This is a retrospective study of histologically confirmed fusion-positive ARMS patients over 18years of age, who were treated at MD Anderson Cancer Center (MDACC) from 2004 to 2021 and received systemic chemotherapy. Descriptive clinical statistics were performed, including staging, front-line chemotherapy, multimodal therapy usage, response rates, and survival analyses. Results: 49 ARMS patients who received upfront chemotherapy were identified. Locoregional treatments included radiotherapy (RT) alone (29%, n = 14), surgery alone (10%, n = 5), or both (45%, n = 22). Median overall survival (OS) for the entire cohort was 3.6years, and the overall response rate to systemic therapy was 89%. No chemotherapy regimen showed OS benefit, specifically analyzing the pediatric-based vincristine, actinomycin-D, cyclophosphamide (VAC) or adult-based vincristine, doxorubicin, ifosfamide (VDI) regimens, even when controlled for other clinical risk factors. Conclusion: In this single-center contemporary series, adult ARMS patient outcomes remain poor. There was no statistically significant OS difference in patients who did or did not receive adult or pediatric based ARMS regimens, although a high overall response rate to chemotherapy was seen across the entire cohort. Based on these observations, further randomized prospective studies are necessary to delineate which frontline chemotherapy regimen is most beneficial in this rare adult cancer.

A Phase 1 Study of Venetoclax in Combination with a Pediatric-Inspired Regimen for the Treatment of Newly Diagnosed Adults with B-Cell Ph-like ALL

Background: Aberrant overexpression of pro-survival Bcl-2 family proteins is one mechanism by which leukemic cells circumvent apoptosis. BCL-2 overexpression is common in various subtypes of B-acute lymphocytic leukemia (ALL), including Philadelphia (Ph)-like ALL. Ph-like ALL is a chemotherapy-resistant disease associated with higher rates of induction failure and persistent measurable residual disease (MRD), and poor overall survival (OS) outcomes with frontline chemotherapy regimens, compared to other subtypes. Venetoclax (VEN) is a selective BCL2 inhibitor, and its addition to pediatric-type frontline regimens could improve response and long-term outcomes for B-ALL, including Ph-like subtype. Design: This is a phase 1 study with an expansion cohort investigating the safety of combining VEN with induction (IND) and consolidation (CON) cycles of the CALGB 10403 backbone regimen (NCT05157971). Post CONS therapy was per the treating physician discretion. The study enrolled newly diagnosed adults [18-54 years (yrs)] with Ph-negative B-ALL. To enrich the study for Ph-like ALL, we excluded patients (pts) with KMT2A-rearranged, TCF3::PBX1, and ETV6::RUNX1 subtypes at diagnosis. Identification of Ph-like ALL was performed using RNA-sequencing, conventional cytogenetics, fluorescence in situ hybridization, and whole genome array studies. Dose level (DL) 1 of VEN was 400 mg orally daily on days 1-14 of IND and CON, with a ramp-up dosing during IND [Day 1= 100 mg, Day 2= 200 mg, Days 3-14= 400 mg/day]. Results: We enrolled 14 pts as of July 1 st, 2023. The median age was 33 (20-53) yrs, of which 9 pts were males and 13 (93%) were Hispanics. Seven (50%) pts had Ph-like ALL (6 with CRLF2-alterations, 1 JAK2-fusion). Six pts were treated on the phase 1 part, and no dose limiting toxicity was observed during IND. Among 14 pts that completed IND, all achieved complete remission (CR), including 1 pt who required an extended IND phase, and 79% (n= 11) achieved MRD- (<0.01%) by multicolor flow (MCF) on day 28 of IND. Eleven pts completed CONS, and all achieved undetectable MRD CR or CR with incomplete count recovery (CRi) by MCF. Post CONS next-generation sequencing of MRD (clonoSEQ) was available for all 11 pts who completed CONS, and 7 (64%) were undetectable while 4 were detected at very low levels (range: 0.0007-0.0024%). Median time to neutrophil count ≥1000 and platelet count ≥100,000 were 19 (15-26) and 14 (2-27) days from starting IND, respectively. No pt died during IND or CONS cycles. Grade ≥3 adverse events at least possibly related to venetoclax and/or the C10403 regimen that occurred in ≥ 20% of evaluable pts during either IND or CONS cycles were leukopenia (100%), neutropenia (100%), lymphopenia (100%), anemia (70%), thrombocytopenia (50%), hyperbilirubinemia (30%) and hypertriglyceridemia (20%). Only 1 pt underwent consolidation with allogeneic stem cell transplant while in remission. With a median follow up for the entire cohort of 7.2 months (range: 1.9-16.1 months), only 1 pt with Ph-like ALL relapsed and he is currently alive. Conclusion: The addition of 14 days of VEN at 400 mg daily dose to a pediatric-inspired regimen during IND and CONS was safe in adults with newly diagnosed B-ALL and did not delay counts recovery. The addition of VEN led to a promising higher than expected MRD- CR rate in high-risk B-ALL, including for pts with Ph-like subtype. The study is actively enrolling on the expansion cohort, and BH3 profiling on pre-treatment and post relapse samples will be performed to determine BCL-2 dependency and correlates to early MRD- response.

The Splicing-Associated Network PAK1-Clk-SRRM1 Is a Critical Vulnerability to Overcome Chemoresistance in Acute Myeloid Leukemia

In Acute Myeloid Leukemia (AML), distinguishing between chemoresistance driver mechanisms and cell plasticity in response to chemotherapy is challenging due to their interconnectedness. To address this issue, we generated an MLL-AF9-driven syngeneic mouse model of AML, which we evolved to develop resistance to a front-line chemotherapy regimen by repetitive exposure to a maximally-tolerated combination of cytarabine and doxorubicin. An RNA sequencing (RNAseq)-based profiling of the chemoresistant (Chemo R) AML subpopulation and its naive (Chemo N) counterpart revealed a significant upregulation in the expression of 326 genes in Chemo R cells which were markedly enriched in gene sets related to splicing/mRNA processing. Notably, single-sample GSEA analysis of relapsed AML samples from the BEAT-AML cohort supported these findings, as they were enriched for the upregulation of genes in our chemoresistance gene signature. A combined in vivo functional screening endeavor using a pool of 2098 shRNAs targeting these upregulated genes and a motif discovery analysis performed on the set of dysregulated transcripts in Chemo R cells identified three candidate hits, Srrm1, Sf3b3, and Prpf8, which scored as chemotherapy-specific dependencies and were found to interact with central regulators of alternative splicing ( Figure 1A). Silencing these three candidate genes in our chemoresistant mouse model and the human AML cell lines, MOLM-14, MV4-11, and U937, evolved to become resistant to the combination of cytarabine and daunorubicin, revealed that the splicing regulator, SRRM1, is a critical vulnerability of chemoresistant leukemic cells. An orthogonal phospho-proteomic approach identified that PAK1 and CLK kinases are regulators of SRRM1 in chemoresistant AML cells, through the phosphorylation of multiple serine and threonine phosphosites in its arginine-rich domain. Human and murine chemoresistant cells were found to be markedly more sensitive to inhibitors of PAKs (FRAX597) and CLKs (TG003 and ML167) compared to their naive counterparts, an effect which was even further enhanced by treatment with cytarabine and daunorubicin. Notably, a whole-exome sequencing pipeline at our institution revealed a clonal variant of uncertain significance (c.1429G>T p.(Ala477Ser)) in PAK1 in an AML patient at relapse. Absence of this variant at diagnosis suggested its association with chemotherapy resistance. Biochemical and cellular assays confirmed that the A477S variant increased PAK1 activation as well as chemotherapy resistance in AML cell lines. This effect could be counteracted by suppressing SRRM1, indicating that PAK1 activation in relapsed AML confers increased vulnerability to SRRM1 suppression. Simultaneous suppression of Clk1 and Pak1 or Clk4 and Pak1 using validated shRNAs and combinations of FRAX597 and TG003, or FRAX597 and ML167 synergized to reduce the growth and the colony-forming capacity of chemoresistant AML cells and sensitized them to chemotherapy. These observations were supported by the RNAseq-based estimate of the inclusion ratios of alternative exons and introns which showed that the combination of PAK and CLK inhibitors phenocopied partially the effects of SRRM1 silencing on splicing perturbations. In preclinical studies, the combined treatment improved overall mouse survival and reduced disease burden in our chemoresistant AML mouse models compared to single-drug treatments ( Figure 1B). Moreover, AML patient cells that were primarily refractory or from a post chemotherapy relapse (n=21) exhibited a higher ex vivo sensitivity to the FRAX597 + TG003 combination in comparison with chemosensitive patients at diagnosis (n=28). Moreover, in NSG-S mice transplanted with matched samples from the same AML patient at diagnosis and relapse post-chemotherapy, combined PAK1 and CLK inhibition more effectively reduced disease progression in animals transplanted with the relapse sample than in those engrafted with the sample taken at diagnosis. In conclusion, our study advances the rationale that combined inhibition of PAK1 and CLK kinases effectively curtails malignant cell splicing adaptation to chemotherapy by affecting SRRM1 function. Combined PAK1 and CLK inhibitors either concomitant with or sequential to chemotherapy may offer greater clinical benefit and significantly improve AML patients' long-term outcomes.

Early T-Cell Precursor Leukemia: A High-Risk Subtype of Acute Lymphoblastic Leukemia, Single Center Experience in Jordan

Background and ObjectivesEarly T-cell precursor (ETP) acute lymphoblastic leukemia/lymphoma (ALL/LBL) is a newly recognized entity of T-lymphoblastic leukemia/lymphoma. The optimal therapeutic approaches to adult patients are poorly studied. Patients and MethodsWe compared the outcomes of adult's patents with ETP-ALL/LBL who received frontline chemotherapy regimens with other T-ALL/LBL immunophenotypic subtypes. Patients with ETP-ALL/LBL were identified based on CD1a (-), CD8 (-), CD5 (-) (dim), and positivity for 1 or more stem cell or myeloid antigens. ResultsSixty-nine patients were included between the years 2010 and 2021 (19 ETP-T-ALL/LBL; 50 non ETP- T-cell ALL/LBL). The median age was 26 year (IQR: 21, 33). Fifty-six patients presented as ALL, while 16 with lymphoblastic lymphoma. Forty-seven patients achieved complete remission, and 43 were alive at last encounter. The complete remission rate in patients with ETP-ALL/LBL was lower than that of non-ETP-ALL/LBL patients (32% vs. 68%; P = .2), and the MRD at end of induction was significantly higher (26% vs. 6.2%, P < .001), and more likely to receive allo-SCT consolidation in CR1 (95% vs. 40%, P < .001). After a median follow-up of survivors of 48 months (range: 32-74 months), the median overall survival for patients with ETP-ALL/LBL was not reached versus 11.5 months for the non-ETP-ALL/LBL patients (P = .014)). Twenty-six patients receive allo-SCT in CR1. There was no significant difference in overall survival (79% vs. 70%; P = .49) between both transplant-cohorts in both groups. ConclusionETP-ALL/LBL represents a high-risk disease subtype of adult ALL. Novel treatment strategies are needed to improve treatment outcomes in this patient's population

Abstract P6-11-15: Lipid accumulation in residual triple negative breast cancer cells surviving chemotherapy treatment

Abstract Background: Triple negative breast cancer (TNBC) is an aggressive breast cancer subtype for which limited targeted therapies are available. Therefore, conventional chemotherapy remains the backbone of standard neoadjuvant treatment (NACT) for TNBC patients. Unfortunately, ~45% of patients will have substantial residual tumor burden post neoadjuvant chemotherapy, leading to poor prognoses (PMID: 28135148). Recently, it has been demonstrated that mitochondrial oxidative phosphorylation (oxphos) is upregulated and is a therapeutic vulnerability in chemoresistant TNBC (PMID: 30996079; Baek et al., BioRxiv doi.org/10.1101/2022.02.25.481996). However, mechanisms driving increased oxphos in chemoresistant TNBC are not understood. Upregulated fatty acid (FA) metabolism is a common adaptation in tumors, providing an energy source through fatty acid β-oxidation (FAO), and promoting lipid accumulation after fatty acid synthesis (FAS) when energy needs are met. Chemotherapy can induce oxidative stress through the generation of reactive oxygen species. Cancer cells adapt to these damaging molecules by increasing de novo lipogenesis, resulting in the accumulation of lipid droplets (LDs) in the cytosol (PMID: 32782526, 20876798). We hypothesize that TNBC cells metabolically adapt to the stress of NACT by upregulating lipid metabolic pathways, providing highly energetic molecules that can be utilized to drive oxphos in chemoresistant TNBC. Methods: Using orthotopic patient-derived xenograft (PDX) models of TNBC (PIM001-P, PMID: 30996079, HCI-010, PMID: 22019887; WHIM14, PMID:24055055), we are measuring protein levels of fatty acid synthase (FASN) in vehicle tumors vs residual tumors surviving treatment with the standard front-line neoadjuvant chemotherapy regimens (Adriamycin plus cyclophosphamide (AC), docetaxel, carboplatin, or docetaxel+carboplatin) using immunohistochemistry (IHC). Vectra 3 microscopy (Akoya) is being used to quantify tumor cell-specific staining. We complemented our IHC analysis with reverse-phase protein array (RPPA). To assess LD accumulation in residual PDX tumors, we conducted transmission electron microscopy (TEM). To complement these PDX studies, we modeled the residual tumor metabolic state in cultured human TNBC cells. Following treatment with the IC50 of standard chemotherapeutic agents (AC, carboplatin, paclitaxel, docetaxel), we assessed oxphos by measuring oxygen consumption rate (OCR) using a Seahorse Bioanalyzer (Agilent). Further, we tested LD accumulation using LipidTOX staining. In ongoing studies, we are measuring incorporation of 13C palmitate into the tricarboxylic acid cycle (TCA) prior to and following chemotherapy treatments to assess if lipids fuel mitochondrial metabolism in residual TNBC cells. Results/Discussion: IHC in the PIM001-P PDX model after in vivo AC treatment revealed increased levels of FASN in post-AC residual tumors compared to the treatment-naive tumors. Further, key proteins involved in fatty acid synthesis, FASN and Acetyl-CoA carboxylase, were significantly increased in residual PIM001-P cells that survived AC compared to vehicle by RPPA. TEM analysis of the HCI-010 PDX revealed significantly more LDs in carboplatin-treated tumors compared to vehicle. This finding was supported by increased LDs observed in TNBC cell lines treated with NACT compared to vehicle in our LipidTOX analyses. Taken together, these data indicate that NACT induces increased expression of key lipid metabolism proteins and accumulation of cytosolic LDs. Our future experiments will reveal if chemoresistant TNBC cells preferentially utilize and incorporate lipids into the tricarboxylic acid cycle, in turn driving oxphos. These data have the potential to provide rationale for the incorporation of FAO/LD inhibitors in sequential combinations with conventional chemotherapies to more effectively kill TNBC cells that are chemo-refractory. Citation Format: Katherine E. Pendleton, Mokryun L. Baek, Junegoo Lee, Lin Tan, Hannah L. Johnson, Lacey E. Dobrolecki, James P. Barrish, Michael T. Lewis, Philip L. Lorenzi, Fabio Stossi, Gloria V. Echeverria. Lipid accumulation in residual triple negative breast cancer cells surviving chemotherapy treatment [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P6-11-15.

Optimal approach to T-cell ALL.

T-lineage acute lymphoblastic leukemia (T-ALL) is curable for most children and adolescent and young adult patients with contemporary frontline chemotherapy regimens. During the past decade, improved survival rates have resulted from the optimization of frontline chemotherapy regimens, the use of minimal residual disease (MRD) assessment for evaluating a patient's risk for relapse, and the intensification of treatment based on the persistence of MRD. Optimization of initial therapy is critical because relapsed T-ALL after initial intensive chemotherapy is incurable for most adult patients. Current T-ALL salvage chemotherapy regimens are minimally effective, and unlike in B-cell ALL, there are no approved antibody therapies or chimeric antigen receptor T-cell therapies for relapsed disease. Immunotherapy and small-molecule inhibitors are beginning to be tested in relapsed T-ALL and have the potential to advance the treatment. Until effective salvage strategies are discovered, however, intensive frontline therapy is required for cure. In this article I review the current frontline chemotherapy regimens for adult patients with T-ALL, summarize the novel targeted and immune therapeutics currently in early-phase clinical trials, and outline how these therapies are helping to define an optimal approach for T-ALL.

Blastic Plasmacytoid Dendritic Cell Neoplasm (BPDCN): Long-Term Outcomes and Novel Observations from a Large BPDCN Cohort

Background: Blastic plasmacytoid dendritic cell neoplasm (BPDCN), is an ultra-rare, clinically aggressive, CD123-overexpressing hematologic malignancy now reclassified in the 5th edition WHO under dendritic cell and histiocytic neoplasms (Khoury J Leukemia 2022). BPDCN is characterized by involvement of 4 major compartments: skin, bone marrow, lymph nodes, and central nervous system (CNS). BPDCN has been historically associated with a lack of treatment options, dismal outcomes (median OS 8-16 months). Now, in the modern treatment era, with CD123-based and combination therapies, emerging data and a number of significant clinical/translational breakthroughs have led to progress in this rare disease field (Pemmaraju N JCO 2022; Pemmaraju N Blood Adv 2022). In this analysis, we aim to describe long-term patient characteristics and outcomes in one of the largest ongoing, single-institution, prospectively followed group of patients (pts) with BPDCN in the world. Patient Characteristics: All pts ages ≥ 18 years with a confirmed pathological diagnosis of BPDCN and treated at our institution were included in this analysis. During Oct 1998-July 2022, 118 pts with BPDCN were identified. Median age was 66 years [range 19-86 years]. 81% were male. At presentation to our institution: n=78 untreated; n=40 had prior therapy (median # prior therapies = 1 [1-5]). Bone marrow (BM) was involved in 75 (64%), skin-only in 41 (35%), lymph node-only in 2 (2%). In addition to CD4+ and CD56+ tumor immunophenotype demonstrated: TCL-1+ (77/77 tested) and CD123+ in 100%. Cytogenetics among 106 pts available: diploid (74%), complex (22%), del (12p) in 2%, miscellaneous (2%). Median BM blast count was 8% [0-95]. Historically, as there has been no standard of care therapeutic approach, a variety of frontline chemotherapy regimens were administered over time (including in this cohort: CD123-based; ALL-based; AML-based; CHOP/lymphoma-based; HMA+VEN based; other regimens). Results, overall cohort (n=118): The median follow-up time was 23 months [4.1 - 91 mo]. Median # of chemotherapy regimens was 1 [1-6]. Median overall survival (OS) was 23 mo [0.9 -158.0 mo]. 78 (66%) pts died, with the most common cause of death being multi-organ failure. Skin-only pts with BPDCN: Remarkably, in this long-term f/u, there was no statistically significant difference between skin (n=41) vs BM involved BPDCN (n=75) in terms of either OS (20 mo vs 23 mo) or CR1 (21 vs 38 mo). SCT: 40 pts (33%) received stem cell transplant (SCT) during CR1. The median OS for pts receiving SCT was statistically significantly superior at 66 mo [5.3-90.8 mo] vs a median OS for non-SCT group in CR1 (n=31) of 23 mo [4.1-158.0], p =0.003. CNS involvement BPDCN: Notably, in this longer f/u of our series, we found that a high rate, 33%, of our pts had CSF+ at any time during the course of their BPDCN, with the vast majority of cases detected on routine/asymptomatic lumbar punctures. Prior or concomitant hematologic malignancies (PCHM): The occurrence of PCHM remains quite common in BPDCN, making up 24% of our total BPDCN population, with MDS/CMML representing the most common PCHM. Next-generation Sequencing (NGS): A molecular gene panel via NGS on BM specimens was done in n=80; 60 (75%) had TET2 abnormality (standard mutation=36, standard+variant=2, variants=22), which was the most common molecular abnormality among our BPDCN cohort. There was no statistically significant difference in terms of OS or CR1 in pts with known TET2 mutations/variants vs all others/not done. The second most common mutation was ASXL1 in 38%, followed by RAS mutations in 19%. Conclusions: This longer-term analysis (med f/u ~ 2 years) of a large, ongoing cohort of pts with BPDCN reveals several important findings including continued overall similar long-term outcomes in skin-only vs BM-involved BPDCN; significant OS improvement in CR1 for younger/fit pts who are able to proceed to SCT when available; a strikingly high incidence of CSF+ in BPDCN which is a higher incidence than previously recognized, and has led to our practice-changing approach of standard incorporation of routine LP with IT chemo for all pts with BPDCN; and a notably common occurrence of PCHM in BPDCN to be aware of in both diagnostic and treatment paradigms. With median OS still only ~2 years, BPDCN remains a highly aggressive hematologic malignancy still in need of active clinical/translational research and novel therapeutic approaches.

A multicenter, real-world analysis of primary central nervous system lymphoma in those with and without human immunodeficiency virus.

A multicenter, real-world analysis of primary central nervous system lymphoma in those with and without human immunodeficiency virus.

Clinical characteristics and outcomes of adult alveolar rhabdomyosarcoma (ARMS) patients on front-line therapies: An MD Anderson Cancer Center (MDACC) case series.

e23548 Background: Rhabdomyosarcomas are the most common soft tissue sarcoma in children, and the prognosis of pediatric ARMS has improved with the use of multi-modality therapies. However, ARMS in adults is rare, and long-term outcomes continue to be poor. This study aimed to evaluate clinical outcomes of an adult ARMS population on different front-line systemic chemotherapies, particularly the vincristine/doxorubicin/ifosfamide (VDI) regimen. Methods: Adult fusion-positive confirmed ARMS patients over the age of 18 years (y) treated at MDACC from 2004 to 2018 were identified in our patient registry. Descriptive clinical statistics including staging, front-line chemotherapy, multimodal therapy usage, and survival analyses were performed. Results: 49 patients were identified, with mean age of 34.9 y (range 18y - 67y), and 53% were male. Most patients were white (53%, 26 pts), and the most common primary tumor site was the parameningeal space (63%; 31 pts). Patients were either intermediate (67%) or high clinical risk (33%). Most patients were IRSG clinical group IIIa (36%), IIIb (20%) or IV (33%) and were classified clinical stage 3 (49%) or 4 (33%). Of all patients at diagnosis, 71% had nodal disease and 32% were metastatic. Radiotherapy and surgery were given with upfront chemotherapy in 33 pts (67%) and 24 pts (49%) respectively, with 19 patients receiving both. Median OS for the entire cohort was 3.6 years. Doxorubicin containing chemotherapy regimens trended to worse OS than non-doxorubicin containing regimens (2.3 yrs vs 4.0 yrs, p = 0.355). Comparing patients who received VDI (19 pts) vs non-VDI (30 pts; 13 received Actinomycin D, 12 received doxorubicin in different regimens, and 5 received neither), median OS was 1.8 yrs vs 3.8 yrs (p = 0.283) respectively. There were similar number of front-line chemotherapy cycles (8.5 vs 9.5 cycles), high clinical risk (26% vs 37%) and metastatic disease (21% vs 36%) in the VDI vs non-VDI cohorts. Patients receiving upfront radiation had improved survival (3.7 vs 1.5 yr, p = 0.01), but this is likely confounded by those with metastases being less likely to receive upfront radiation. Conclusions: In this single center retrospective analysis of adult ARMS patients, survival outcomes continue to be similar to historical outcomes. There was no statistically significant OS difference in patients who did or did not receive doxorubicin containing front-line chemotherapy regimens, or in particular VDI therapy, although there was a trend to decreased OS. However, limitations to this study include limited sample size, non-randomization to treatment selection, and possible biases in patient selection for different chemo regimens. Based on these observations, randomized prospective studies are necessary to delineate which frontline chemotherapy regimen is most beneficial in this rare tumor in adults.

Clinical outcomes for patients with thymoma and thymic carcinoma after undergoing different front-line chemotherapy regimens.

BackgroundFront‐line platinum‐base chemotherapy for advanced thymoma and thymic carcinoma (TC) improves resectability and prolongs patients' overall survival (OS). In this study, we evaluated patients' outcomes given different front‐line regimens: cisplatin, doxorubicin, and cyclophosphamide (CAP); cisplatin and etoposide (EP); or cisplatin and paclitaxel (TP).Materials and MethodsWe retrospectively evaluated the medical records of patients with advanced thymoma and TC who were treated at our medical center between 2005 and 2015. We investigated objective response rates (ORRs), progression‐free survival (PFS), and OS after undergoing different front‐line regimens.ResultsAmong the 108 enrolled patients, 37 (34%) had thymoma and 71 (66%) had TC; 45 received CAP, 36 received EP, and 27 received TP regimens. The ORRs of patients receiving CAP, EP, and TP were 51%, 50%, and 41%, respectively. For patients with stage III and IVA disease, the median PFS after CAP, EP, and TP were 34.5, 26.4, and 18.0 months (p = 0.424), respectively, and the 5‐year OS rates were 84.9%, 70.6%, and 60.0% (p = 0.509). In patients with stage IVB disease, the median PFS were 9.4, 8.2, and 11.6 months after undergoing CAP, EP, and TP (p = 0.173), respectively, and the 5‐year OS rates were 41.1%, 39.1%, and 14.3% (p = 0.788). TC pathology subtype and liver metastasis were associated with poor OS. Three patients with stage IVB TC had an OS of more than 5 years.ConclusionDifferent front‐line chemotherapy regimens may provide similar long‐term PFS and OS in patients with advanced thymoma and TC. In addition to TC and liver metastasis were associated with poor OS, other potential prognostic factors are warranted for studying.

Long-Term Outcomes in Patients with Blastic Plasmacytoid Dendritic Cell Neoplasm (BPDCN)

Long-Term Outcomes in Patients with Blastic Plasmacytoid Dendritic Cell Neoplasm (BPDCN)

Differential Depletion of Bone Marrow Resident B-ALL after Systemic Administration of Endosomal TLR Agonists.

Acute lymphoblastic leukemia (ALL) is the most common pediatric malignancy. While frontline chemotherapy regimens are generally very effective, the prognosis for patients whose leukemia returns remains poor. The presence of measurable residual disease (MRD) in bone marrow at the completion of induction therapy is the strongest predictor of relapse, suggesting that strategies to eliminate the residual leukemic blasts from this niche could reduce the incidence of recurrence. We have previously reported that toll-like receptor (TLR) agonists achieve durable T cell-mediated protection in transplantable cell line-based models of B cell precursor leukemia (B-ALL). However, the successful application of TLR agonist therapy in an MRD setting would require the induction of anti-leukemic immune activity specifically in the bone marrow, a site of the chemotherapy-resistant leukemic blasts. In this study, we compare the organ-specific depletion of human and mouse primary B-ALL cells after systemic administration of endosomal TLR agonists. Despite comparable splenic responses, only the TLR9 agonist induced strong innate immune responses in the bone marrow and achieved a near-complete elimination of B-ALL cells. This pattern of response was associated with the most significantly prolonged disease-free survival. Overall, our findings identify innate immune activity in the bone marrow that is associated with durable TLR-induced protection against B-ALL outgrowth.

An evaluation of brentuximab vedotin as a treatment option for stage III/IV Hodgkin lymphoma

ABSTRACTIntroduction: Outcomes of patients with classical Hodgkin lymphoma are excellent, and the intent of frontline therapy for even advanced-stage disease has been curative. This review summarizes the role of brentuximab vedotin in the upfront treatment of advanced stage classical Hodgkin lymphoma in the context of reducing therapy-related toxicity without compromising the high cure rate.Areas covered: Strategies to reduce bleomycin-induced lung toxicity include a response-adapted approach investigated in the RATHL study and a replacement of bleomycin with brentuximab vedotin in frontline chemotherapy regimens. In both studies, omission of bleomycin in the non-standard arms decreased the rate of pulmonary toxicity while maintaining high progression-free survival and overall survival rates.Expert opinion: The approval of A+AVD in North America offers a new bleomycin-free regimen for the treatment of advanced-stage HL, but it must be balanced against a risk-adapted approach. Recently presented subset analyses raise a question about which patients benefit most from this therapy.

Frontline treatment of elderly non transplant-eligible multiple myeloma patients using CyBorD with or without thalidomide-based consolidation: a retrospective multi-centre analysis of real-world data.

Bortezomib in combination with cyclophosphamide and dexamethasone (CyBorD, is a well-established frontline chemotherapy regimen for patients with multiple myeloma, but prospective data on elderly non-transplant eligible patients is limited. A total of 155 patients aged 70years or older with newly diagnosed multiple myeloma who received at least one cycle of CyBorD chemotherapy in three centres across New Zealand were evaluated. Partial response or better was achieved in 79·4%, of whom 52·9% achieved at least a very good partial response. After a median follow-up of 31·9months, the median event-free survival (EFS) was 17·0months (age 70-80years, 17·7months; age above 80years, 8·6months; P=0·002). The median overall survival was 45·1months (age 70-80, 49·8months; above 80, 33·3months; P=0·003). Amongst those who had seven or more cycles of treatment, those who had a pre-planned switch to bortezomib-thalidomide-dexamethasone (VTD) consolidation had a superior median EFS of 25·4months, compared with 20·3months in the CyBorD only group (P=0·028). This is the largest real-world dataset on the efficacy of CyBorD in the elderly population, and pre-planned switch to VTD was associated with better outcomes.

Outcomes in Patients with Blastic Plasmacytoid Dendritic Cell Neoplasm (BPDCN): Longer-Term Follow-up Demonstrates Poor Outcomes in Patients with Skin-Only Presentation

Outcomes in Patients with Blastic Plasmacytoid Dendritic Cell Neoplasm (BPDCN): Longer-Term Follow-up Demonstrates Poor Outcomes in Patients with Skin-Only Presentation

Multicenter Analysis of Advanced Stage Grade 3A Follicular Lymphoma Outcomes by Frontline Treatment Regimen

BackgroundFollicular lymphoma (FL) is a common form of non-Hodgkin lymphoma with a wide spectrum of presentation. While grade 1/2 FL is considered low grade and grade 3B FL is approached as an aggressive lymphoma, the management of grade 3A FL remains controversial. Patients and MethodsWe performed a retrospective, multicenter analysis of patients aged ≥ 18 years with advanced stage 3/4 grade 3A FL diagnosed between January 2006 and July 2016. Patients were stratified by frontline chemotherapy regimen: anthracycline based (ATC), bendamustine (BD), and cyclophosphamide, vincristine, and prednisone (CVP). A total of 103 patients were identified from 6 contributing centers: 65 patients received ATC chemotherapy, 30 BD, and 8 CVP. The primary outcome was time to progression (TTP). Secondary outcomes included progression-free survival, overall survival, complete response rates, large cell transformation, and impact of standardized maximum uptake value on positron emission tomography/computed tomography with outcomes. Patient characteristics were similar among the 3 treatment groups. ResultsFor TTP at 24 months from initiation of treatment, 72% of ATC, 79% of BD, and 50% of CVP patients had not experienced disease progression (P = .01). Multivariate analysis demonstrated a TTP benefit for ATC compared to CVP (hazard ratio 3.22; 95% confidence interval, 1.26-8.25; P = .01) but no difference when compared to BD. Similar findings were seen with progression-free survival. While overall survival was similar among the 3 arms, there was a higher risk of large cell transformation following BD and CVP. Last, standardized maximum uptake value on positron emission tomography/computed tomography did not affect TTP when comparing BD- and ATC-treated patients. ConclusionAlthough ATC was superior to CVP, clinical outcomes (TTP, progression-free survival, and overall survival) were similar compared to BD chemotherapy for patients with grade 3A FL.