How comparable are patient outcomes in the "real-world" with populations studied in pivotal AML trials?

Despite an increasing desire to use historical cohorts as "synthetic" controls for new drug evaluation, limited data exist regarding the comparability of real-world outcomes to those in clinical trials. Governmental cancer data often lacks details on treatment, response, and molecular characterization of disease sub-groups. The Australasian Leukaemia and Lymphoma Group National Blood Cancer Registry (ALLG NBCR) includes source information on morphology, cytogenetics, flow cytometry, and molecular features linked to treatment received (including transplantation), response to treatment, relapse, and survival outcome. Using data from 942 AML patients enrolled between 2012-2018, we assessed age and disease-matched control and interventional populations from published randomized trials that led to the registration of midostaurin, gemtuzumab ozogamicin, CPX-351, oral azacitidine, and venetoclax. Our analyses highlight important differences in real-world outcomes compared to clinical trial populations, including variations in anthracycline type, cytarabine intensity and scheduling during consolidation, and the frequency of allogeneic hematopoietic cell transplantation in first remission. Although real-world outcomes were comparable to some published studies, notable differences were apparent in others. If historical datasets were used to assess the impact of novel therapies, this work underscores the need to assess diverse datasets to enable geographic differences in treatment outcomes to be accounted for.

Sorafenib plus intensive chemotherapy in newly diagnosed FLT3-ITD AML: a randomized, placebo-controlled study by the ALLG.

Sorafenib maintenance improves outcomes after hematopoietic cell transplant (HCT) for patients with FMS-like tyrosine kinase 3-internal tandem duplication (FLT3-ITD) acute myeloid leukemia (AML). Although promising outcomes have been reported for sorafenib plus intensive chemotherapy, randomized data are limited. This placebo-controlled, phase 2 study (ACTRN12611001112954) randomized 102 patients (aged 18-65 years) 2:1 to sorafenib vs placebo (days 4-10) combined with intensive induction: idarubicin 12 mg/m2 on days 1 to 3 plus either cytarabine 1.5 g/m2 twice daily on days 1, 3, 5, and 7 (18-55 years) or 100 mg/m2 on days 1 to 7 (56-65 years), followed by consolidation and maintenance therapy for 12 months (post-HCT excluded) in newly diagnosed patients with FLT3-ITD AML. Four patients were excluded in a modified intention-to-treat final analysis (3 not commencing therapy and 1 was FLT3-ITD negative). Rates of complete remission (CR)/CR with incomplete hematologic recovery were high in both arms (sorafenib, 78%/9%; placebo, 70%/24%). With 49.1-months median follow-up, the primary end point of event-free survival (EFS) was not improved by sorafenib (2-year EFS 47.9% vs 45.4%; hazard ratio [HR], 0.87; 95% confidence interval [CI], 0.51-1.51; P = .61). Two-year overall survival (OS) was 67% in the sorafenib arm and 58% in the placebo arm (HR, 0.76; 95% CI, 0.42-1.39). For patients who received HCT in first remission, the 2-year OS rates were 84% and 67% in the sorafenib and placebo arms, respectively (HR, 0.45; 95% CI, 0.18-1.12; P = .08). In exploratory analyses, FLT3-ITD measurable residual disease (MRD) negative status (<0.001%) after induction was associated with improved 2-year OS (83% vs 60%; HR, 0.4; 95% CI, 0.17-0.93; P = .028). In conclusion, routine use of pretransplant sorafenib plus chemotherapy in unselected patients with FLT3-ITD AML is not supported by this study.

Epstein-Barr virus-related lymphoma in rheumatoid arthritis: implications for long-term usage of immunosuppressive drugs and review of the literature.

BACKGROUND: Rheumatoid arthritis (RA) is a common autoimmune disease where methotrexate (MTX) is widely used as the first-line therapy. The combination of RA and MTX is associated with lymphoproliferative disorders (LPD). RA patients with Epstein-Barr virus (EBV) have impaired T-lymphocyte function, thus allowing an overgrowth of EBV-positive lymphoblastoid cells. We examined the association of EBV with LPD in immunosuppressed RA patients, particularly those treated with MTX. AIM: To review the relationship between RA, EBV-associated LPD and MTX use. METHODS: We reported two cases of RA patients with long-term MTX treatment who subsequently developed EBV-positive LPD, followed by a review of the relevant literature. RESULTS: Compared with normal population, RA patients have a higher risk of lymphoma, with diffuse large B-cell lymphoma being the most common subtype. MTX withdrawal can lead to lymphoma regression. Other biological therapies, such as abatacept and tocilizumab, are not associated with increased EBV-positive lymphoma diagnosis in RA patients. CONCLUSION: The association between EBV, lymphoma and MTX highlights the need to consider reducing or stopping MTX in patients who have had stable RA for many years.

Outpatient rituximab, ifosfamide, etoposide (R-IE) in patients older than 60 years with relapsed or refractory diffuse large B-cell lymphoma who are not candidates for stem cell transplantation.

Patients with relapsed-refractory diffuse large B-cell lymphoma (RR-DLBCL) ineligible for autologous stem cell transplantation (autoSCT) have poor survival. Thirty transplant-ineligible patients older than 60 years were administered rituximab 375 mg/m2 day 1, ifosfamide 1333 mg/m2 days 1 to 3, and etoposide 80 mg/m2 days 1 to 3 (R-IE) every 21 days for 6 cycles plus 2 doses of rituximab. Revised international prognostic index 3-4 was seen in 53% and prior rituximab exposure in 60%. The complete and overall response rates were 55% and 76%, respectively. Median progression free survival (PFS) and overall survival were 23 and 24 months, respectively. Patients relapsing within 12 months of prior treatment had a median PFS of 2.5 months compared to 23 months for those relapsing beyond 12 months. Grade 3-4 thrombocytopenia and neutropenia occurred in one and eight patients, respectively. R-IE is an effective, well tolerated regimen in RR-DLBCL patients not fit for autoSCT.

Efficacy and safety of nilotinib 300 mg twice daily in patients with chronic myeloid leukemia in chronic phase who are intolerant to prior tyrosine kinase inhibitors: Results from the Phase IIIb ENESTswift study.

BACKGROUND: Some patients receiving a tyrosine kinase inhibitor (TKI) for the first-line treatment of chronic phase chronic myeloid leukemia (CML-CP) experience intolerable adverse events. Management strategies include dose adjustments, interrupting or discontinuing therapy, or switching to an alternative TKI. METHODS: This multicenter, single-arm, Phase IIIb study included CML-CP patients intolerant of, but responsive to, first-line treatment with imatinib or dasatinib. All patients were switched to nilotinib 300 mg bid for up to 24 months. The primary endpoint was achievement of MR4.5 (BCR-ABL transcript level of ≤0.0032% on the International Scale) by 24 months. RESULTS: Twenty patients were enrolled in the study (16 imatinib-intolerant, 4 dasatinib-intolerant); which was halted early because of low recruitment. After the switch to nilotinib 300 mg bid, MR4.5 at any time point up to month 24 was achieved in 10 of 20 patients (50%) in the full analysis set. Of the non-hematological adverse events associated with intolerance to prior imatinib or dasatinib, 74% resolved within 12 weeks of switching to nilotinib 300 mg bid. CONCLUSION: Nilotinib 300 mg bid shows minimal cross intolerance in patients with CML-CP who have prior toxicities to other TKIs and can lead to deep molecular responses.

Idarubicin Dose Escalation During Consolidation Therapy for Adult Acute Myeloid Leukemia.

Purpose Higher doses of the anthracycline daunorubicin during induction therapy for acute myeloid leukemia (AML) have been shown to improve remission rates and survival. We hypothesized that improvements in outcomes in adult AML may be further achieved by increased anthracycline dose during consolidation therapy. Patients and Methods Patients with AML in complete remission after induction therapy were randomly assigned to receive two cycles of consolidation therapy with cytarabine 100 mg/m2 daily for 5 days, etoposide 75 mg/m2 daily for 5 days, and idarubicin 9 mg/m2 daily for either 2 or 3 days (standard and intensive arms, respectively). The primary end point was leukemia-free survival (LFS). Results Two hundred ninety-three patients 16 to 60 years of age, excluding those with core binding factor AML and acute promyelocytic leukemia, were randomly assigned to treatment groups (146 to the standard arm and 147 to the intensive arm). Both groups were balanced for age, karyotypic risk, and FLT3-internal tandem duplication and NPM1 gene mutations. One hundred twenty patients in the standard arm (82%) and 95 patients in the intensive arm (65%) completed planned consolidation ( P < .001). Durations of severe neutropenia and thrombocytopenia were prolonged in the intensive arm, but there were no differences in serious nonhematological toxicities. With a median follow-up of 5.3 years (range, 0.6 to 9.9 years), there was a statistically significant improvement in LFS in the intensive arm compared with the standard arm (3-year LFS, 47% [95% CI, 40% to 56%] v 35% [95% CI, 28% to 44%]; P = .045). At 5 years, the overall survival rate was 57% in the intensive arm and 47% in the standard arm ( P = .092). There was no evidence of selective benefit of intensive consolidation within the cytogenetic or FLT3-internal tandem duplication and NPM1 gene mutation subgroups. Conclusion An increased cumulative dose of idarubicin during consolidation therapy for adult AML resulted in improved LFS, without increased nonhematologic toxicity.

Early treatment intensification with R-ICE and 90Y-ibritumomab tiuxetan (Zevalin)-BEAM stem cell transplantation in patients with high-risk diffuse large B-cell lymphoma patients and positive interim PET after 4 cycles of R-CHOP-14.

In the treatment of diffuse large B-cell lymphoma, a persistently positive [18F]fluorodeoxyglucose positron emission tomography (PET) scan typically carries a poor prognosis. In this prospective multi-center phase II study, we sought to establish whether treatment intensification with R-ICE (rituximab, ifosfamide, carboplatin, and etoposide) chemotherapy followed by 90Y-ibritumomab tiuxetan-BEAM (BCNU, etoposide, cytarabine, and melphalan) for high-risk diffuse large B-cell lymphoma patients who are positive on interim PET scan after 4 cycles of R-CHOP-14 (rituximab, cyclophosphamide, doxorubicin, and prednisone) can improve 2-year progression-free survival from a historically unfavorable rate of 40% to a rate of 65%. Patients received 4 cycles of R-CHOP-14, followed by a centrally-reviewed PET performed at day 17-20 of cycle 4 and assessed according to International Harmonisation Project criteria. Median age of the 151 evaluable patients was 57 years, with 79% stages 3-4, 54% bulk, and 54% International Prognostic Index 3-5. Among the 143 patients undergoing interim PET, 101 (71%) were PET-negative (96 of whom completed R-CHOP), 42 (29%) were PET-positive (32 of whom completed R-ICE and 90Y-ibritumomab tiuxetan-BEAM). At a median follow up of 35 months, the 2-year progression-free survival for PET-positive patients was 67%, a rate similar to that for PET-negative patients treated with R-CHOP-14 (74%, P=0.11); overall survival was 78% and 88% (P=0.11), respectively. In an exploratory analysis, progression-free and overall survival were markedly superior for PET-positive Deauville score 4 versus score 5 (P=0.0002 and P=0.001, respectively). Therefore, diffuse large B-cell lymphoma patients who are PET-positive after 4 cycles of R-CHOP-14 and who switched to R-ICE and 90Y-ibritumomab tiuxetan-BEAM achieved favorable survival outcomes similar to those for PET-negative R-CHOP-14-treated patients. Further studies are warranted to confirm these promising results. (Registered at: ACTRN12609001077257).

Use of arsenic trioxide in remission induction and consolidation therapy for acute promyelocytic leukaemia in the Australasian Leukaemia and Lymphoma Group (ALLG) APML4 study: a non-randomised phase 2 trial.

BACKGROUND: Initial treatment of acute promyelocytic leukaemia traditionally involves tretinoin (all-trans retinoic acid) combined with anthracycline-based risk-adapted chemotherapy, with arsenic trioxide being the treatment of choice at relapse. To try to reduce the relapse rate, we combined arsenic trioxide with tretinoin and idarubicin in induction therapy, and used arsenic trioxide with tretinoin as consolidation therapy. METHODS: Patients with previously untreated genetically confirmed acute promyelocytic leukaemia were eligible for this study. Eligibilty also required Eastern Cooperative Oncology Group performance status 0-3, age older than 1 year, normal left ventricular ejection fraction, Q-Tc interval less than 500 ms, absence of serious comorbidity, and written informed consent. Patients with genetic variants of acute promyelocytic leukaemia (fusion of genes other than PML with RARA) were ineligible. Induction comprised 45 mg/m(2) oral tretinoin in four divided doses daily on days 1-36, 6-12 mg/m(2) intravenous idarubicin on days 2, 4, 6, and 8, adjusted for age, and 0·15 mg/kg intravenous arsenic trioxide once daily on days 9-36. Supportive therapy included blood products for protocol-specified haemostatic targets, and 1 mg/kg prednisone daily as prophylaxis against differentiation syndrome. Two consolidation cycles with tretinoin and arsenic trioxide were followed by maintenance therapy with oral tretinoin, 6-mercaptopurine, and methotrexate for 2 years. The primary endpoints of the study were freedom from relapse and early death (within 36 days of treatment start) and we assessed improvement compared with the 2 year interim results. To assess durability of remission we compared the primary endpoints and disease-free and overall survival at 5 years in APML4 with the 2 year interim APML4 data and the APML3 treatment protocol that excluded arsenic trioxide. This study is registered with the Australian New Zealand Clinical Trials Registry, number ACTRN12605000070639. FINDINGS: 124 patients were enrolled between Nov 10, 2004, and Sept 23, 2009, with data cutoff of March 15, 2012. Four (3%) patients died early. After a median follow-up of 4·2 years (IQR, 3·2-5·2), the 5 year freedom from relapse was 95% (95% CI 89-98), disease-free survival was 95% (89-98), event-free survival was 90% (83-94), and overall survival was 94% (89-97). The comparison with APML3 data showed that hazard ratios were 0·23 (95% CI 0·08-0·64, p=0·002) for freedom from relapse, 0·21 (0·07-0·59, p=0·001) for disease-free survival, 0·34 (0·16-0·69, p=0·002) for event-free survival, and 0·35 (0·14-0·91, p=0·02) for overall survival. INTERPRETATION: Incorporation of arsenic trioxide in initial therapy induction and consolidation for acute promyelocytic leukaemia reduced the risk of relapse when compared with historical controls. This improvement, together with a non-significant reduction in early deaths and absence of deaths in remission, translated into better event-free and overall survival. FUNDING: Phebra.

TIDEL-II: first-line use of imatinib in CML with early switch to nilotinib for failure to achieve time-dependent molecular targets.

The Therapeutic Intensification in De Novo Leukaemia (TIDEL)-II study enrolled 210 patients with chronic phase chronic myeloid leukemia (CML) in two equal, sequential cohorts. All started treatment with imatinib 600 mg/day. Imatinib plasma trough level was performed at day 22 and if <1000 ng/mL, imatinib 800 mg/day was given. Patients were then assessed against molecular targets: BCR-ABL1 ≤10%, ≤1%, and ≤0.1% at 3, 6, and 12 months, respectively. Cohort 1 patients failing any target escalated to imatinib 800 mg/day, and subsequently switched to nilotinib 400 mg twice daily for failing the same target 3 months later. Cohort 2 patients failing any target switched to nilotinib directly, as did patients with intolerance or loss of response in either cohort. At 2 years, 55% of patients remained on imatinib, and 30% on nilotinib. Only 12% were >10% BCR-ABL1 at 3 months. Confirmed major molecular response was achieved in 64% at 12 months and 73% at 24 months. MR4.5 (BCR-ABL1 ≤0.0032%) at 24 months was 34%. Overall survival was 96% and transformation-free survival was 95% at 3 years. This trial supports the feasibility and efficacy of an imatinib-based approach with selective, early switching to nilotinib. This trial was registered at www.anzctr.org.au as #12607000325404.

All-trans-retinoic acid, idarubicin, and IV arsenic trioxide as initial therapy in acute promyelocytic leukemia (APML4).

The treatment of acute promyelocytic leukemia has improved considerably after recognition of the effectiveness of all-trans-retinoic acid (ATRA), anthracycline-based chemotherapy, and arsenic trioxide (ATO). Here we report the use of all 3 agents in combination in an APML4 phase 2 protocol. For induction, ATO was superimposed on an ATRA and idarubicin backbone, with scheduling designed to exploit antileukemic synergy while minimizing cardiotoxicity and the severity of differentiation syndrome. Consolidation comprised 2 cycles of ATRA and ATO without chemotherapy, followed by 2 years of maintenance with ATRA, oral methotrexate, and 6-mercaptopurine. Of 124 evaluable patients, there were 4 (3.2%) early deaths, 118 (95%) hematologic complete remissions, and all 112 patients who commenced consolidation attained molecular complete remission. The 2-year rate for freedom from relapse is 97.5%, failure-free survival 88.1%, and overall survival 93.2%. These outcomes were not influenced by FLT3 mutation status, whereas failure-free survival was correlated with Sanz risk stratification (P[trend] = .03). Compared with our previously reported ATRA/idarubicin-based protocol (APML3), APML4 patients had statistically significantly improved freedom from relapse (P = .006) and failure-free survival (P = .01). In conclusion, the use of ATO in both induction and consolidation achieved excellent outcomes despite a substantial reduction in anthracycline exposure. This trial was registered at the Australian New Zealand Clinical Trials Registry (www.anzctr.org.au) as ACTRN12605000070639.

A loss-of-function polymorphic mutation in the cytolytic P2X7 receptor gene and chronic lymphocytic leukaemia: a molecular study.

BACKGROUND: Chronic lymphocytic leukaemia (CLL) has a familial incidence nearly three times higher than expected for the general population and one predisposing factor might be an inherited failure of mechanisms involved in apoptosis of lymphocytes. Our aim was to ascertain whether or not a defect in a proapoptotic pathway, caused by a single nucleotide polymorphism that results in loss-of-function of P2X7 in healthy individuals, was present in leukaemic B lymphocytes of patients with CLL. METHODS: We extracted genomic DNA from the peripheral blood leucocytes of 36 unrelated individuals with CLL, four individuals with familial CLL, and 46 age-matched controls. We sequenced a PCR product to detect mutations in exon 13 of P2X7. In most patients with CLL, we measured expression and function of the P2X7 receptor by flow cytometry in B lymphocytes and T lymphocytes. FINDINGS: The prevalence of the polymorphic mutation and the frequency of the mutant allele were three-fold greater in individuals with CLL than in white, elderly controls. Individuals homozygous for the polymorphic allele had no P2X7 receptor function and heterozygotes had half the mean function of that seen in individuals homozygous for the wildtype allele; amounts of ATP-induced apoptosis varied accordingly. In two families, in which we studied a father-son pair and a sister-sister pair with CLL, loss of P2X7 function arose because of inheritance of one or two 1513A-->C alleles for P2X7. INTERPRETATION: Activation of the P2X7 receptor leads to apoptosis of lymphocytes in individuals with CLL, and reduced function of this receptor has an anti-apoptotic effect, resulting in an increase in B-cell numbers. Thus, inheritance of a loss-of-function polymorphic mutation at position 1513 in the P2X7 gene could contribute to the pathogenesis of CLL.