Heerema, Nyla A.

7503 Background: Prior to use of novel targeted agents for CLL, debate existed regarding the best chemoimmunotherapy regimen to build upon in patients (pts) with non-del(11q) disease. The role of lenalidomide (L) was also not defined. CALGB 10404 was a randomized phase 2 study addressing these questions. Methods: Pts with untreated CLL requiring therapy were randomized to treatment with fludarabine + rituximab (FR), FR + 6 monthly consolidative treatments of L (5 mg days 1-21/28 x 1 then 10 mg days 1-21/28 x 5) (FR+L), or FR + cyclophosphamide (FCR). Based on pretreatment central interphase cytogenetic screening, pts with del(11q22.3) in at least 20% of cells were excluded from the primary analysis, testing whether 2-year progression-free survival (PFS) rate was improved in non-del(11q) pts within each arm. A target accrual of 103 non-del(11q) pts per arm provided at least 84% power to detect an increase in 2-year PFS rate from 60% to 73%; the critical value was 69% using a single stage design and type I error rate of 4%. Results: A total of 342 non-del(11q) CLL pts were randomized to treatment with FR (n = 123), FR+L (n = 109), or FCR (n = 110). Baseline characteristics were similar across arms. Two-year PFS rates with exact 90% CIs were 64% (57-71%) (FR), 71% (63-78%) (FR+L), and 74% (66-80%) (FCR). Median PFS was significantly shorter with FR compared to FR+L (p = 0.03) and FCR (p < 0.01): 43 (95% CI: 33-50), 66 (95% CI: 45-not reached), and 78 (95% CI: 58-not reached) months respectively. Median overall survival (OS) has not been reached for any arm. OS at 1, 2, and 3 years was similar across arms, although there was a plateau in OS with no events beyond 41 months in the FR+L arm, different from FR/FCR where events continued to occur. The most common adverse events were cytopenias and infections. Conclusions: FR+L and FCR met the protocol defined primary endpoint. FR+L extended PFS relative to FR and a plateau in survival differentiated this arm from the FR/FCR arms. Future studies comparing FR+L to FCR or incorporating L into other novel treatment regimens are justified. Support: U10CA180821, U10CA180882, Celgene. Clinical trial information: NCT00602459.

Key PointsBrief lenalidomide consolidation after chemoimmunotherapy is acceptably tolerated and extends PFS and OS in CLL. FCR has superior efficacy compared with FR chemoimmunotherapy for CLL.

AALL08P1 was designed to determine whether biweekly intensified pegaspargase (I-PEG) was feasible and safe in pediatric patients with newly diagnosed high-risk B-precursor lymphoblastic leukemia when given with Children’s Oncology Group hemiaugmented BFM therapy. High-risk average (HR-Avg) patients received standard pegaspargase dosing (6 doses), whereas high-risk high (HR-High) patients received I-PEG biweekly from the start of Consolidation until day 1 of Maintenance. Feasibility and safety were defined in advance as ≥65% of patients tolerating at least 8 doses of I-PEG and 90% requiring ≤49 weeks from day 1 of Consolidation to the initiation of Maintenance. Targeted toxicities included allergic reactions, anaphylaxis, pancreatitis, thrombosis, bleeding, central nervous system events, and sepsis. AALL08P1 enrolled 104 patients; 54 were classified as HR-Avg and 30 as HR-High after completion of induction therapy. Only 53% (16/30) of the HR-High patients received ≥8 total doses of I-PEG and 50% (15/30) took ≤49 weeks from start of Consolidation to the initiation of Maintenance. I-PEG did not significantly increase grade 2 to 5 targeted toxicities. I-PEG was not feasible or safe as defined in AALL08P1. Complete assessment of this regimen was limited due to removal of patients from I-PEG regimen and early closure of the study.

SummaryThis study revisited the Dohner prognostic hierarchy in a cohort of 1585 well‐documented patients with chronic lymphocytic leukaemia. The duration of both time to first treatment (TTFT) and overall survival (OS) were significantly longer than observed previously, and this is at least partly due to improved therapeutic options. Deletion 13q remains the most favourable prognostic group with median TTFT and OS from fluorescence in situ hybridization (FISH) testing of 72 months and >12 years, respectively. Deletion 11q had the poorest median TTFT (22 months) and 17p deletion the poorest median OS (5 years). The percentages of abnormal nuclei were significantly associated with differential TTFT for the trisomy 12, 13q and 17p deletion cohorts but not for the 11q deletion cohort. From the date of the first FISH study, patients with >85% 13q deletion nuclei had a notably shorter TTFT (24 months). Patients with ≤20% 17p deletion nuclei had longer median TTFT and OS from the date of the first FISH study (44 months and 11 years), and were more likely to be IGHV mutated.

Key PointsIn this first ALL GWAS in AYAs, we determined that inherited GATA3 variants strongly influence ALL susceptibility in this age group. These findings revealed similarities and differences in the genetic basis of ALL susceptibility between young children and AYAs.

Purpose To evaluate the prognostic significance of the international European LeukemiaNet (ELN) guidelines for reporting genetic alterations in acute myeloid leukemia (AML). Patients and Methods We analyzed 1,550 adults with primary AML, treated on Cancer and Leukemia Group B first-line trials, who had pretreatment cytogenetics and, for cytogenetically normal patients, mutational status of NPM1, CEBPA, and FLT3 available. We compared complete remission (CR) rates, disease-free survival (DFS), and overall survival (OS) among patients classified into the four ELN genetic groups (favorable, intermediate-I, intermediate-II, adverse) separately for 818 younger (age < 60 years) and 732 older (age ≥ 60 years) patients. Results The percentages of younger versus older patients in the favorable (41% v 20%; P < .001), intermediate-II (19% v 30%; P < .001), and adverse (22% v 31%; P < .001) genetic groups differed. The favorable group had the best and the adverse group the worst CR rates, DFS, and OS in both age groups. Both intermediate groups had significantly worse outcomes than the favorable but better than the adverse group. Intermediate-I and intermediate-II groups in older patients had similar outcomes, whereas the intermediate-II group in younger patients had better OS but not better CR rates or DFS than the intermediate-I group. The prognostic significance of ELN classification was confirmed by multivariable analyses. For each ELN group, older patients had worse outcomes than younger patients. Conclusion The ELN classification clearly separates the genetic groups by outcome, supporting its use for risk stratification in clinical trials. Because they have different proportions of genetic alterations and outcomes, younger and older patients should be reported separately when using the ELN classification.

Abstract Myeloid cell leukemia-1 (Mcl-1) is an antiapoptotic member of the Bcl-2 protein family. Increased Mcl-1 expression is associated with failure to achieve remission after treatment with fludarabine and chlorambucil in patients with chronic lymphocytic leukemia (CLL). However, the influence of Mcl-1 expression has not been examined in CLL trials using chemoimmunotherapy. We investigated Mcl-1 protein expression prospectively as part of a phase 2 study evaluating the efficacy of pentostatin, cyclophosphamide, and rituximab in patients with untreated CLL. No significant difference by Mcl-1 expression was noted in pretreatment or response parameters. However, in patients with higher Mcl-1 expression, both minimal residual disease-negative status and progression-free survival was found to be significantly reduced (57% vs 19%, P = .01; 50.8 vs 18.7 months; P = .02; respectively). Mcl-1 expression may therefore be useful in predicting poor response to chemoimmunotherapy. These findings further support pursuing treatment strategies targeting this important antiapoptotic protein. (Because the trials described were conducted before the requirement to register them was implemented, they are not registered in a clinical trial database.)

AbstractCCG-2961 incorporated 3 new agents, idarubicin, fludarabine and interleukin-2, into a phase 3 AML trial using intensive-timing remission induction/consolidation and related donor marrow transplantation or high-dose cytarabine intensifi-cation. Among 901 patients under age 21 years, 5-year survival was 52%, and event-free survival was 42%. Survival improved from 44% between 1996 and 1998 to 58% between 2000 and 2002 (P = .005), and treatment-related mortality declined from 19% to 12% (P = .025). Partial replacement of daunomycin with idarubicin in the 5-drug induction combination achieved a remission rate of 88%, similar to historical controls. Postremission survival was 56% in patients randomized to either 5-drug reinduction or fludarabine/cytarabine/idarubicin. For patients with or without a related donor, respective 5-year disease-free survival was 61% and 50% (P = .021); respective survival was 68% and 62% (P = .425). Donor availability conferred no benefit on those with inv(16) or t(8;21) cytogenetics. After cytarabine intensification, patients randomized to interleukin-2 or none experienced similar outcomes. Factors predictive of inferior survival were age more than 16 years, non-white ethnicity, absence of related donor, obesity, white blood cell count more than 100 000 × 109/L, −7/7q−, −5/5q−, and/or complex karyotype. No new agent improved outcomes; experience may have contributed to better results time.

AbstractBuilding on the prior work of use of pentostatin in chronic lymphocytic leukemia (CLL), we initiated a trial of combined pentostatin (2 mg/m2), cyclophosphamide (600 mg/m2), and rituximab (375 mg/m2) for 65 symptomatic, previously untreated patients. Of 64 evaluable patients, 34 (53%) were high Rai risk, 71% were nonmutated for the immunoglobulin heavy-chain variable region gene, 34% were CD38+, and 34% were ZAP-70+. Thirty patients (52%) had one anomaly detected by fluorescence in situ (FISH) hybridization, and 21 (36%) had complex FISH defects. Thirty-eight patients (58%) had grade 3+ hematologic toxicity but minimal transfusion needs and no major infections. Responses occurred in 58 patients (91%), with 26 (41%) complete responses (CRs), 14 (22%) nodular partial responses (nodular PRs), and 18 (28%) partial responses (PRs). Many patients with a CR also lacked evidence of minimal residual disease by 2-color flow cytometry. Examination of prognostic factors demonstrated poor response in the 3 patients with del(17p). In contrast, we found this regimen was equally effective in young versus older (> 70 years) patients and in del(11q22.3) versus other favorable prognostic factors. Thus, this novel regimen of pentostatin, cyclophosphamide, and rituximab for previously untreated patients with CLL demonstrated significant clinical activity despite poor risk-based prognoses, achievement of minimal residual disease in some, and modest toxicity.