Cost-Effectiveness and Economic Burden Analyses on All First-Line Treatments of Chronic Lymphocytic Leukemia.

OBJECTIVES: Several chemoimmunotherapy and targeted treatment regimens are approved as front-line therapies in chronic lymphocytic leukemia. We estimated for the 10-year cost-effectiveness of these treatment regimens and the economic burden of following the estimated risk-stratified 21 040 patients with chronic lymphocytic leukemia diagnosed in 2020 for 10 years. METHODS: A Markov model with 7 exclusive health states was specified over a 10-year time horizon. Treatment effectiveness inputs were obtained from a novel network meta-analysis on the progression-free survival, overall survival curves, and time to next treatment. Costs and utilities inputs were included for each health state for each treatment and discounted at 3.0%/year. Life-years (LYs) and quality-adjusted LYs (QALYs) for each treatment were determined. Using the lowest cost regimen as reference, the incremental cost-effectiveness ratio (ICER) and incremental cost-utility ratio (ICUR) were estimated. The 10-year per-patient cost was determined by risk status and by initial treatment. RESULTS: Venetoclax-plus-obinutuzumab was the lowest cost regimen, hence the reference. Superior in effectiveness to all chemoimmunotherapies, it was cost saving. With the highest effectiveness gains at 6.26 LYs and 5.01 QALYs and despite being the most expensive regimen ($1 298 638 per patient), acalabrutinib-plus-obinutuzumab yielded the best ICER ($409 343/LY gained) and ICUR ($501 236/QALY gained). The remaining ICERs of targeted therapies ranged from $512 101/LY gained to $793 236/LY gained and the ICURs from $579 737/QALY gained to $869 300/QALY gained. The 10-year postdiagnosis low/high (venetoclax-plus-obinutuzumab/acalabrutinib-plus-obinutuzumab) economic burden ranges were $42 690 to $98 665 for low-risk, $141 339 to $326 660 for intermediate-risk, and $273 650 to $632 453 for high-risk patients. CONCLUSIONS: Compared with venetoclax-plus-obinutuzumab, chemoimmunotherapies are associated with less health benefits at higher cost. The targeted therapies achieve greater benefits at higher cost.

Safety and Efficacy of Engineered Toxin Body MT-3724 in Relapsed or Refractory B-cell Non-Hodgkin's Lymphomas and Diffuse Large B-cell Lymphoma.

MT-3724, a novel engineered toxin body comprised of an anti-CD20 single-chain variable fragment genetically fused to Shiga-like Toxin A subunit, is capable of binding to and internalizing against CD20, inducing cell killing via permanent ribosomal inactivation. This study evaluated MT-3724 in patients with relapsed/refractory B-cell non-Hodgkin lymphoma (r/rNHL). This open-label, multiple-dose phase Ia/b trial included a dose escalation in patients with r/rNHL according to a standard 3+3 design. Primary objectives were to determine the MTD and pharmacokinetics/pharmacodynamics. In a dose expansion study at MTD in serum rituximab-negative patients with diffuse large B-cell lymphoma (DLBCL), primary objectives were safety, tolerability, and pharmacokinetics/pharmacodynamics. Twenty-seven patients enrolled. MTD was 50 µg/kg/dose with 6,000 µg/dose cap. Thirteen patients experienced at least one grade ≥3 treatment-related adverse events; the most common grade ≥3 event was myalgia (11.1%). Two patients (75 µg/kg/dose) experienced grade 2 treatment-related capillary leak syndrome. Overall objective response rate was 21.7%. In serum rituximab-negative patients with DLBCL or composite DLBCL (n = 12), overall response rate was 41.7% (complete response, n = 2; partial response, n = 3). In patients with detectable baseline peripheral B cells, treatment resulted in dose-dependent B-cell depletion. The proportion of patients with anti-drug antibodies (ADA) increased during treatment and the majority appeared to be neutralizing based on an in vitro assay; nevertheless, tumor regression and responses were observed. MT-3724 demonstrated efficacy at the MTD in this population of previously treated patients with r/rDLBCL, with mild-to-moderate immunogenic safety events. Significance: This work describes the safety and efficacy of a new pharmaceutical pathway that could provide a treatment option for a subset of patients with a critical unmet therapeutic need. The study drug, MT-3724, is capable of targeting B-cell lymphomas via a unique, potent cell-killing mechanism that appears to be promising.

Targeting JAK/STAT Signaling Antagonizes Resistance to Oncolytic Reovirus Therapy Driven by Prior Infection with HTLV-1 in Models of T-Cell Lymphoma.

Human T-cell leukemia virus type 1 (HTLV-1) is a retrovirus that infects at least 10 million people worldwide and is associated with the development of T-cell lymphoma (TCL). The treatment of TCL remains challenging and new treatment options are urgently needed. With the goal of developing a novel therapeutic approach for TCL, we investigated the activity of the clinical formulation of oncolytic reovirus (Reolysin, Pelareorep) in TCL models. Our studies revealed that HTLV-1-negative TCL cells were highly sensitive to Reolysin-induced cell death, but HTLV-1-positive TCL cells were resistant. Consistent with these data, reovirus displayed significant viral accumulation in HTLV-1-negative cells, but failed to efficiently replicate in HTLV-1-positive cells. Transcriptome analyses of HTLV-1-positive vs. negative cells revealed a significant increase in genes associated with retroviral infection including interleukin-13 and signal transducer and activator of transcription 5 (STAT5). To investigate the relationship between HTLV-1 status and sensitivity to Reolysin, we infected HTLV-1-negative cells with HTLV-1. The presence of HTLV-1 resulted in significantly decreased sensitivity to Reolysin. Treatment with the JAK inhibitor ruxolitinib suppressed STAT5 phosphorylation and expression of the key anti-viral response protein MX1 and enhanced the anti-TCL activity of Reolysin in both HTLV-1-positive and negative cells. Our data demonstrate that the inhibition of the JAK/STAT pathway can be used as a novel approach to antagonize the resistance of HTLV-1-positive cells to oncolytic virus therapy.

Comparative Efficacy of First-Line Treatments of Chronic Lymphocytic Leukemia: Network Meta-Analyses of Survival Curves.

BACKGROUND: Multiple treatment options in first-line chronic lymphocytic leukemia (CLL) pose a challenge in identifying the best treatment. We performed novel network meta-analyses (NMA; 8 trials, 11 treatments) on the Kaplan-Meier curves to compare treatments for fludarabine-ineligible patients on progression-free survival (PFS), time-to-next-treatment (TTNT) and overall survival (OS). METHODS: Using the Guyot method of enhanced secondary analysis of digitized survival data and applying the fixed lognormal distribution model, we extracted the survival proportions and hazard ratios (HR) over 60 months of follow-up, including PFS comparisons by unmutated/mutated IGHV and del 17p. RESULTS: Acalabrutinib-plus-obinutuzumab was associated with higher 5-year PFS proportions than ibrutinib (HR = 0.42, 95% CrI = 0.25-0.63) but not acalabrutinib, ibrutinib-plus-obinutuzumab, ibrutinib-plus-rituximab or venetoclax-plus-obinutuzumab. In patients with un-mutated (but not with mutated) IGHV higher PFS proportions and favorable HRs were observed for acalabrutinib, acalabrutinib-plus-obinutuzumab, and ibrutinib-plus-obinutuzumab relative to ibrutinib; and targeted therapies were superior over chemoimmunotherapies in patients with del 17p. Targeted therapies containing ibrutinib or acalabrutinib regimens were associated with superior TTNT over venetoclax-plus-obinutuzumab and all chemoimmunotherapies. OS NMA generally found no difference between therapies except for some chemoimmunotherapies. CONCLUSIONS: Overall, only acalabrutinib-plus-obinutuzumab was associated with superior 5-year PFS gains over ibrutinib, which in turn was similar or superior in PFS benefit over other targeted therapies. Acalabrutinib and ibrutinib with obinutuzumab and acalabrutinib monotherapy were associated with greater 5-year TTNT benefits. Despite marked 5-year OS for many regimens, a differential 5-year OS benefit could not be ascertained.

Survival trends in chronic lymphocytic leukemia across treatment eras: US SEER database analysis (1985-2017).

In this population-based study, we used the SEER database (1985-2015) to examine survival outcomes in chronic lymphocytic leukemia (CLL) patients followed up to the era of advanced treatments including targeted therapies. Data were extracted for patients 15 years or older with a primary diagnosis of CLL. A period analysis was performed to estimate 5- and 10-year relative survival rates for patients diagnosed during different calendar periods from 1985 to 2015. A mixture cure model was used to examine long-term survivors' proportions among patients diagnosed in 1985-2015 and for two cohorts diagnosed in 2000-2003, followed up to 2012 and 2004-2007, and followed up to 2015. Cox proportional hazard modeling was used for the two cohorts to estimate hazard ratios (HRs) of death adjusted for gender and age. The 5-year and 10-year age-adjusted relative survival rate ranged between 73.7 and 89.4% and from 51.6% to "not reached," respectively, for calendar periods of 1985-1989 to 2010-2014. The long-term survivor proportions varied by age and gender from 0 to 59%. The HRs (95%CI) for the 2004-2007 cohort in comparison to the 2000-2003 cohort were 0.58 (0.43-0.78), 0.58 (0.48-0.70), 0.57 (0.49-0.0.67), 0.68 (0.54-0.85), and 0.83 (0.68-1.02) for the age categories of 45-54, 55-64, 65-74, 75-84, and ≥ 85 years, respectively. Overall, relative survival improved significantly for CLL patients diagnosed between 1985 and 2015. These improvements were markedly better following the introduction of targeted therapies.

Outcomes of primary and secondary prophylaxis of chemotherapy-induced and febrile neutropenia in bendamustine plus rituximab regimens in patients with lymphoma and chronic lymphocytic leukemia: real-world, single-center experience.

PURPOSE: To examine the outcomes associated with granulocyte colony stimulating factors (G-CSFs) administered as primary versus secondary prophylaxis in setting of bendamustine plus rituximab (BR) regimens. METHODS: Eighty-five patients who underwent treatment for non-Hodgkin's lymphoma (NHL) or chronic lymphocytic leukemia (CLL) with BR at the University of Arizona Cancer Center from November 2013 to June 2019 were evaluated through retrospective chart review. Patients were stratified into two groups: those who were given G-CSF for primary prophylaxis (n = 47) and for secondary prophylaxis (n = 38). G-CSF-included filgrastim or pegfilgrastim. The primary endpoints were incidence of febrile neutropenia and grade 3 or 4 neutropenia. RESULTS: Same-day G-CSF compared with next-day G-CSF was the most common G-CSF dosing method utilized in primary and secondary prophylaxis (94% and 100%), respectively. Primary and secondary prophylaxis groups were similar on baseline characteristics (p > 0.05); the primary outcome of FN (p > 0.05); all secondary outcomes (p > 0.05) except for a higher frequency of dose delays in secondary (40%) vs primary prophylaxis patients (13%; p = 0.01), and mean absolute neutrophil counts (ANC) in cycles 1 through 5. With higher ANC levels observed during all cycles in the primary prophylaxis group compared with secondary prophylaxis. CONCLUSIONS: In this single-center retrospective study, BR-treated lymphoma and CLL patients receiving primary versus secondary with G-CSF showed similar outcomes except, notably, for chemotherapy dose delays that may put secondary patients at risk for poor treatment outcomes. Further research is needed to evaluate the impact of primary versus secondary prophylaxis on treatment outcomes.

Incorporating acalabrutinib, a selective next-generation Bruton tyrosine kinase inhibitor, into clinical practice for the treatment of haematological malignancies.

Greater understanding of the mechanisms involved in the disease progression of haematological malignancies has led to the introduction of novel targeted therapies with reduced toxicity compared with chemotherapy-based regimens, which has expanded the treatment options for patients with mantle cell lymphoma (MCL) and chronic lymphocytic leukaemia/small lymphocytic lymphoma (CLL/SLL). Ibrutinib is a first-in-class Bruton tyrosine kinase (BTK) inhibitor indicated for the treatment of patients with CLL/SLL or relapsed/refractory MCL. However, next-generation BTK inhibitors have been developed with improved specificity and the potential to reduce the off-target toxicity observed with ibrutinib. Acalabrutinib is a highly selective, next-generation BTK inhibitor, which was granted accelerated approval by the US Food and Drug Administration in 2017 for the treatment of adult patients with MCL who have received at least one prior therapy. In November 2019, it was also granted approval for the treatment of adult patients with CLL/SLL on the basis of two phase 3 clinical trials. This review describes the current understanding of acalabrutinib according to clinical study data for the treatment of MCL and CLL/SLL and shares recommendations from our practice on how it should be used when treating patients in the clinic, including dosing, administration and management of adverse events.

Resistance to histone deacetylase inhibitors confers hypersensitivity to oncolytic reovirus therapy.

Despite the promising antilymphoma activity of histone deacetylase (HDAC) inhibitors as a drug class, resistance is a significant clinical issue. Elucidating the molecular mechanisms driving HDAC inhibitor resistance and/or the specific targets that are altered in drug-resistant cells may facilitate the development of strategies that overcome drug resistance and are more effective for refractory patients. We generated novel T-cell lymphoma (TCL) cell line models of acquired resistance to the HDAC inhibitor belinostat to identify potential effective therapies. Belinostat-resistant cells displayed significant cross-resistance to other HDAC inhibitors including romidepsin, panobinostat, and vorinostat. Consistent with a lack of sensitivity to HDAC inhibitors, the resistant cells failed to induce increased acetylated histones. Drug-resistant cells featured significantly decreased expression of the key antiviral mediators IRF1 and STAT1. On the basis of these findings, we investigated the efficacy of the clinical formulation of reovirus (Reolysin) in parental and drug-resistant models. Our investigation revealed that HDAC inhibitor-resistant cells displayed enhanced vulnerability to reovirus replication and cell death in both in vitro and in vivo models compared with their parental counterparts. Importantly, Reolysin also significantly increased the antilymphoma activity of belinostat in HDAC inhibitor-resistant cells. Our data demonstrate that Reolysin alone or in combination with belinostat is a novel therapeutic strategy to treat TCL patients who develop resistance to HDAC inhibitors.

Positron Emission Tomography-Directed Therapy for Patients With Limited-Stage Diffuse Large B-Cell Lymphoma: Results of Intergroup National Clinical Trials Network Study S1001.

PURPOSE: Diffuse large B-cell lymphoma (DLBCL) presents as a limited-stage disease in 25% to 30% of patients, with better overall survival (OS) than that for advanced-stage disease but with continuous relapse regardless of treatment approach. The preferred treatment is abbreviated rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) and radiation therapy. On the basis of promising results of positron emission tomography (PET)-directed treatment approaches, we designed a National Clinical Trials Network (NCTN) study to improve outcomes and decrease toxicity. METHODS: Patients with nonbulky (< 10 cm) stage I/II untreated DLBCL received 3 cycles of standard R-CHOP therapy and underwent a centrally reviewed interim PET/computed tomography scan (iPET). Those with a negative iPET proceeded with 1 additional cycle of R-CHOP, whereas those with a positive iPET received involved field radiation therapy followed by ibritumomab tiuxetan radioimmunotherapy. RESULTS: Of 158 patients enrolled, 132 were eligible and 128 underwent iPET, which was positive in 14 (11%) of the patients. With a median follow-up of 4.92 years (range, 1.1-7.7 years), only 6 patients progressed and 3 died as a result of lymphoma. Eleven patients died as a result of nonlymphoma causes at a median age of 80 years. The 5-year progression-free survival estimate was 87% (95% CI, 79% to 92%) and the OS estimate was 89% (95% CI, 82% to 94%), with iPET-positive and iPET-negative patients having similar outcomes. CONCLUSION: To our knowledge, S1001 is the largest prospective study in the United States of limited-stage DLBCL in the rituximab era, with the best NCTN results in this disease subset. With PET-directed therapy, 89% of the patients with a negative iPET received R-CHOP × 4, and only 11% had a positive iPET and required radiation, with both groups having excellent outcomes. The trial establishes R-CHOP × 4 alone as the new standard approach to limited-stage disease for the absolute majority of patients.

Follicular Lymphoma: Recent and Emerging Therapies, Treatment Strategies, and Remaining Unmet Needs.

Follicular lymphoma (FL) is a heterogeneous disease with varying prognosis owing to differences in clinical, laboratory, and disease parameters. Although generally considered incurable, prognosis for early- and advanced-stage disease has improved because of therapeutic advances, several of which have resulted from elucidation of the biologic and molecular basis of the disease. The choice of treatment for FL is highly dependent on patient and disease characteristics. Several tools are available for risk stratification, although limitations in their routine clinical use exist. For limited disease, treatment options include radiotherapy, rituximab monotherapy or combination regimens, and surveillance. Treatment of advanced disease is often determined by tumor burden, with surveillance or rituximab considered for low tumor burden and chemoimmunotherapy for high tumor burden disease. Treatment for relapsed or refractory disease is influenced by initial first-line therapy and the duration and quality of the response. Presently, there is no consensus for treatment of patients with early or multiply relapsed disease; however, numerous agents, combination regimens, and transplant options have demonstrated efficacy. Although the number of therapies available to treat FL has increased together with an improved understanding of the underlying biologic basis of disease, the best approach to select the most appropriate treatment strategy for an individual patient at a particular time continues to be elucidated. This review considers prognostication and the evolving treatment landscape of FL, including recent and emergent therapies as well as remaining unmet needs. IMPLICATIONS FOR PRACTICE: In follicular lymphoma, a personalized approach to management based on disease biology, patient characteristics, and other factors continues to emerge. However, application of current management requires an understanding of the available therapeutic options for first-line treatment and knowledge of current development in therapies for previously untreated and for relapsed or refractory disease. Thus, this work reviews for clinicians the contemporary data in follicular lymphoma, from advances in characterizing disease biology to current treatments and emerging novel therapies.

R-CHOP, radioimmunotherapy, and maintenance rituximab in untreated follicular lymphoma (SWOG S0801): a single-arm, phase 2, multicentre study.

BACKGROUND: Despite an abundance of therapeutic options, advanced-stage follicular lymphoma remains incurable. Furthermore, the ideal sequence and absolute benefit of post-induction therapy is unclear. We designed SWOG S0801 to assess the efficacy and safety of consolidative radioimmunotherapy and sequential maintenance rituximab following chemoimmunotherapy. METHODS: For this single-arm, phase 2, multicentre study, we enrolled patients aged 18 years and older with a diagnosis of stage III, IV, or bulky stage II follicular lymphoma, grades 1, 2, or 3a, who had not received previous therapy, from from 20 institutions within the United States National Cancer Institute Clinical Trials Network. Patients were assigned to a 5-year treatment plan consisting of R-CHOP (rituximab plus cyclophosphamide [750 mg/m2], doxorubicin [50 mg/m2], vincristine [1·4 mg/m2], and prednisone or prednisolone [100 mg]) every 21 days for up to six cycles, with rituximab 375 mg/m2 given on day 1 of cycles 1-4, followed by 131iodine tositumomab radioimmunotherapy and subsequent maintenance rituximab 375 mg/m2 within 12 weeks after the sixth cycle of R-CHOP, every 3 months for up to 4 years. The primary endpoint was 3-year progression-free survival in the intention-to-treat population. Efficacy and safety analyses were done in the intention-to-treat population and the per-protocol population. This trial was registered with ClinicalTrials.gov, number NCT00770224. FINDINGS: Between April 1, 2009, and Dec 15, 2010, we enrolled 84 evaluable patients, of whom 73 completed R-CHOP and radioimmunotherapy. Of 69 patients who registered to maintenance therapy, only 41 completed the 4-year rituximab maintenance treatment. Progression-free survival at 3 years was 90% (95% CI 82-95). The most common grade 3 or worse adverse events included neutropenia in 48 (57%) patients, leucopenia in 34 (40%) patients, thrombocytopenia in 17 (20%) patients, and febrile neutropenia in 14 (17%) patients. Nine patients had possible treatment-related deaths during the study from secondary or unknown causes (n=3), cirrhosis (n=1), cardiac arrest (n=1), and secondary malignancies (n=4). Secondary malignancies occurred in seven patients, including two sarcomas, two colorectal carcinomas, two acute myelogenous leukaemias, and one case of renal-cell carcinoma. INTERPRETATION: SWOG S0801 showed near universal responses following chemoimmunotherapy and radioimmunotherapy. However, most discontinuations occurred during maintenance therapy, suggesting that rituximab over a 4-year span is not feasible for many patients. Nonetheless, this sequential therapeutic strategy resulted in good overall outcomes for patients, including a low incidence of early disease progression. FUNDING: The National Cancer Institute and GlaxoSmithKline.

Yttrium-90-Ibritumomab Tiuxetan (Zevalin®) Radioimmunotherapy after Cytoreduction with ESHAP Chemotherapy in Patients with Relapsed Follicular Non-Hodgkin Lymphoma: Final Results of a Phase II Study.

BACKGROUND: Radioimmunotherapy (RIT) is effective in treating relapsed/refractory follicular lymphoma (FL), with durable remissions in first-line consolidation. We hypothesized that RIT with ibritumomab tiuxetan (Zevalin®) would result in durable remissions by eliminating minimal residual disease after cytoreduction. METHODS: Patients with FL received 2 cycles of ESHAP (etoposide, methylprednisolone, cytarabine, cisplatin) every 28 days, followed by Zevalin 4-6 weeks later if there was no disease progression and bone marrow biopsy showed < 25% involvement. RESULTS: Twenty-eight patients were treated, with a median age of 61 years, median of 3 prior therapies, 49% high-risk disease (Follicular Lymphoma International Prognostic Index, FLIPI), and 39% progressive disease. Three patients did not receive Zevalin due to residual bone marrow involvement. The main toxicities were cytopenias, with 11% febrile neutropenia. The overall response rate (ORR) was 72%, with 45% achieving complete response. With a median follow-up of 73 months, 1-year progression-free survival (PFS) was 38%, and median PFS was 10 months, but median overall survival (OS) was not reached. CONCLUSION: The study did not reach its primary endpoint of a 1-year PFS of 67.3%. Reasons for this could include low accrual, high-risk disease, and inadequate debulking provided by 2 cycles of ESHAP. However, this protocol was associated with tolerable toxicity, high ORR, and high OS. Further studies would optimize debulking and focus on high-risk FL patients.

Phase 2 Open-Label Study of Bortezomib, Cladribine, and Rituximab in Advanced, Newly Diagnosed, and Relapsed/Refractory Mantle-Cell and Indolent Lymphomas.

BACKGROUND: Mantle-cell lymphoma (MCL) and indolent non-Hodgkin lymphoma (iNHL) are incurable heterogeneous diseases characterized by relapse. There is a need for newer treatments in MCL and iNHL, especially in the relapsed/refractory (R/R) setting. We therefore investigated the novel combination of bortezomib (Velcade), cladribine, and rituximab (VCR) in front-line and R/R settings in MCL and iNHL (NCT00980395). PATIENTS AND METHODS: Eligible patients included adults with biopsy-proven CD20-positive MCL and iNHL who met the criteria for treatment. Rituximab 375 mg/m2 intravenous (IV) day 1, cladribine 4 mg/m2 IV days 1 to 5, and bortezomib 1.3 mg/m2 IV days 1 and 4 were administered every 28 days for 6 cycles. RESULTS: Twenty-four patients were enrolled onto the study with a median follow-up of 38.5 months. Median age was 66.5 years, and 46% had MCL. The most common adverse events were hematologic, with febrile neutropenia in 3 patients. Neuropathy was noted in 17% of patients, of which 8% was grade 3 or above. The overall response rate was 92%. For the entire cohort, and for MCL patients, the median progression-free survival and the median overall survival were not reached. The 2-year progression-free survival was 82% for the MCL group and 54% for the iNHL group; it was 80% for treatment-naive patients and 57% for R/R patients. CONCLUSION: VCR is effective in MCL and iNHL. Although hematologic toxicity can be an issue, this study demonstrates a high response rate to a novel combination and provides an alternative option in transplant-ineligible R/R MCL and iNHL.