Optimal sequencing of ibrutinib, idelalisib, and venetoclax in chronic lymphocytic leukemia: results from a multicenter study of 683 patients.

Background: Ibrutinib, idelalisib, and venetoclax are approved for treating CLL patients in the United States. However, there is no guidance as to their optimal sequence. Patients and methods: We conducted a multicenter, retrospective analysis of CLL patients treated with kinase inhibitors (KIs) or venetoclax. We examined demographics, discontinuation reasons, overall response rates (ORR), survival, and post-KI salvage strategies. Primary endpoint was progression-free survival (PFS). Results: A total of 683 patients were identified. Baseline characteristics were similar in the ibrutinib and idelalisib groups. ORR to ibrutinib and idelalisib as first KI was 69% and 81%, respectively. With a median follow-up of 17 months (range 1-60), median PFS and OS for the entire cohort were 35 months and not reached. Patients treated with ibrutinib (versus idelalisib) as first KI had a significantly better PFS in all settings; front-line [hazard ratios (HR) 2.8, CI 1.3-6.3, P = 0.01], relapsed-refractory (HR 2.8, CI 1.9-4.1, P < 0.001), del17p (HR 2.0, CI 1.2-3.4, P = 0.008), and complex karyotype (HR 2.5, CI 1.2-5.2, P = 0.02). At the time of initial KI failure, use of an alternate KI or venetoclax had a superior PFS when compared with chemoimmunotherapy. Furthermore, patients who discontinued ibrutinib due to progression or toxicity had marginally improved outcomes if they received venetoclax (ORR 79%) versus idelalisib (ORR 46%) (PFS HR .6, CI.3-1.0, P = 0.06). Conclusions: In the largest real-world experience of novel agents in CLL, ibrutinib appears superior to idelalisib as first KI. Furthermore, in the setting of KI failure, alternate KI or venetoclax therapy appear superior to chemoimmunotherapy combinations. The use of venetoclax upon ibrutinib failure might be superior to idelalisib. These data support the need for trials testing sequencing strategies to optimize treatment algorithms.

Association of socioeconomic status with autologous hematopoietic cell transplantation outcomes for lymphoma.

Socioeconomic status (SES) is an important determinant of disparities in health care. The association of SES with outcomes in autologous hematopoietic cell transplantation (AHCT) has not been described previously. We conducted a retrospective cohort study of 687 AHCT recipients with lymphoma transplanted between 2003 and 2013. Patients were categorized into low (<$50 000/year) and high SES (⩾$50 000/year). A greater proportion of low SES patients lived farther away from our center (median 54 vs 28 miles), belonged to a racial minority (12 vs 3%), had poorer performance status (4 vs 1%) and had high-risk disease at AHCT (9 vs 5%). Median follow-up was 53 months. In univariable analysis, low SES patients had significantly higher relapse mortality and lower OS and PFS. This was confirmed on multivariable analysis for relapse mortality (HR for high vs low SES: 0.74 (95% confidence interval (CI), 0.54-0.99), P=0.05), OS (HR 0.74 (0.58-0.95), P=0.02) and PFS (HR 0.77 (0.63-0.95), P=0.02). In multivariable analysis of ⩾1-year progression-free survivors, high SES patients had better OS (HR 0.73, P=0.05 vs low SES) that was primarily driven by a trend toward lower risk of non-relapse mortality (HR 0.62, P=0.06). SES is associated with outcomes of AHCT in patients with lymphoma.

Defining AML and MDS second cancer risk dynamics after diagnoses of first cancers treated or not with radiation.

Risks of acute myeloid leukemia (AML) and/or myelodysplastic syndromes (MDS) are known to increase after cancer treatments. Their rise-and-fall dynamics and their associations with radiation have, however, not been fully characterized. To improve risk definition we developed SEERaBomb R software for Surveillance, Epidemiology and End Results second cancer analyses. Resulting high-resolution relative risk (RR) time courses were compared, where possible, to results of A-bomb survivor analyses. We found: (1) persons with prostate cancer receiving radiation therapy have increased RR of AML and MDS that peak in 1.5-2.5 years; (2) persons with non-Hodgkin lymphoma (NHL), lung and breast first cancers have the highest RR for AML and MDS over the next 1-12 years. These increased RR are radiation specific for lung and breast cancer but not for NHL; (3) AML latencies were brief compared to those of A-bomb survivors; and (4) there was a marked excess risk of acute promyelocytic leukemia in persons receiving radiation therapy. Knowing the type of first cancer, if it was treated with radiation, the interval from first cancer diagnosis to developing AML or MDS, and the type of AML, can improve estimates of whether AML or MDS cases developing in this setting are due to background versus other processes.

Association of socioeconomic status with long-term outcomes in 1-year survivors of allogeneic hematopoietic cell transplantation.

The relationship of socioeconomic status (SES) with long-term outcomes in allogeneic hematopoietic cell transplantation (HCT) survivors has not been well described. We studied the association of SES with the outcomes of 283 consecutive allogeneic HCT recipients transplanted between 2003 and 2012 who had survived for at least 1 year in remission. Median annual household income was estimated using Census tract data and from ZIP code of residence. SES categories were determined by recursive partitioning analysis (low SES (<$51 000/year), N=203; high SES (⩾$51 000/year), N=80). In multivariable analyses, low SES patients had higher risks of all-cause mortality (hazard ratio (HR) 1.98, P=0.012) and non-relapse mortality (NRM) (HR 2.22, P=0.028), but similar risks of relapse mortality (HR 1.01, P=0.97) compared with high SES patients. A trend toward better survival and lower NRM for high SES patients with no chronic GVHD was observed; low SES patients without GVHD had similar survival as patients with chronic GVHD. In allogeneic HCT survivors who survive in remission for at least 1 year, SES is associated with long-term survival that is primarily mediated through higher risks of NRM. More research is needed to understand the mechanisms of health-care disparities and interventions to mitigate them.

Prognostic significance of pre-transplant quality of life in allogeneic hematopoietic cell transplantation recipients.

Quality of life (QOL) is an important outcome for hematopoietic cell transplantation (HCT) recipients. Whether pre-HCT QOL adds prognostic information to patient and disease related risk factors has not been well described. We investigated the association of pre-HCT QOL with relapse, non-relapse mortality (NRM), and overall mortality after allogeneic HCT. From 2003 to 2012, the Functional Assessment of Cancer Therapy-Bone Marrow Transplant Scale instrument was administered before transplantation to 409 first allogeneic HCT recipients. We examined the association of the three outcomes with (1) individual QOL domains, (2) trial outcome index (TOI) and (3) total score. In multivariable models with individual domains, functional well-being (hazard ratio (HR) 0.95, P=0.025) and additional concerns (HR 1.39, P=0.002) were associated with reduced risk of relapse, no domain was associated with NRM, and better physical well-being was associated with reduced risk of overall mortality (HR 0.97, P=0.04). TOI was not associated with relapse or NRM but was associated with reduced risk of overall mortality (HR 0.93, P=0.05). Total score was not associated with any of the three outcomes. HCT-comorbidity index score was prognostic for greater risk of relapse and mortality but not NRM. QOL assessments, particularly physical functioning and functional well-being, may provide independent prognostic information beyond standard clinical measures in allogeneic HCT recipients.

Racial differences in allogeneic hematopoietic cell transplantation outcomes among African Americans and whites.

The impact of race on outcome has been identified in a number of cancers, with African Americans having poorer survival compared with whites. We conducted a study to investigate the association of race with allogeneic hematopoietic cell transplant (HCT) outcomes. We identified 789 patients (58 African Americans and 731 whites) who underwent allogeneic HCT for hematologic disorders. There were no significant differences between African Americans and white patients in gender, performance status or comorbidity score. However, African Americans were younger than whites (median 40 years versus 47 years, P=0.003) and were more likely to be in remission at HCT (74% versus 57%, P=0.011), to have an HLA-mismatched donor (36% versus 14%, P<0.001), to have positive donor or recipient CMV serostatus (90% versus 69%, P<0.001) and to have received a cord blood transplant (21% versus 6%, P<0.001). In univariate analysis, African Americans had worse overall survival (OS) (HR 1.41, P=0.026) compared with whites, with no significant differences in acute or chronic GvHD, non-CMV infection or relapse. However, after adjusting for several transplant and disease-related factors in multivariate analysis, the OS difference between African Americans and whites became nonsignificant (HR 1.27, P=0.18). These results suggest that race in and of itself does not lead to worse survival post HCT.

Identification of Ezrin-Radixin-Moesin proteins as novel regulators of pathogenic B-cell receptor signaling and tumor growth in diffuse large B-cell lymphoma.

Diffuse large B-cell lymphoma (DLBCL) is a hematological cancer associated with an aggressive clinical course. The predominant subtypes of DLBCL display features of chronic or tonic B-cell antigen receptor (BCR) signaling. However, it is not known whether the spatial organization of the BCR contributes to the regulation of pro-survival signaling pathways and cell growth. Here, we show that primary DLBCL tumors and patient-derived DLBCL cell lines contain high levels of phosphorylated Ezrin-Radixin-Moesin (ERM) proteins. The surface BCRs in both activated B cell and germinal B cell subtype DLBCL cells co-segregate with phosphoERM suggesting that the cytoskeletal network may support localized BCR signaling and contribute to pathogenesis. Indeed, ablation of membrane-cytoskeletal linkages by dominant-negative mutants, pharmacological inhibition and knockdown of ERM proteins disrupted cell surface BCR organization, inhibited proximal and distal BCR signaling, and reduced the growth of DLBCL cell lines. In vivo administration of the ezrin inhibitor retarded the growth of DLBCL tumor xenografts, concomitant with reduction in intratumor phosphoERM levels, dampened pro-survival signaling and induction of apoptosis. Our results reveal a novel ERM-based spatial mechanism that is coopted by DLBCL cells to sustain tumor cell growth and survival.

Outcomes after autologous SCT in lymphoma patients grouped by weight.

Obesity continues to be an increasing global health issue contributing to the complexity of chemotherapy dosing in the field of SCT. Investigation into the optimal dosing weight used to calculate chemotherapy doses in obese patients undergoing SCT is limited and inconclusive. Our single-center, retrospective study compared safety and efficacy outcomes by body mass index (BMI) for 476 adult lymphoma patients who underwent auto-SCT with a myeloablative chemotherapeutic regimen of BU, CY and etoposide dosed using adjusted body weight. Three weight groups categorized based on BMI were defined: normal/underweight ⩽24.9 kg/m(2), overweight 25-29.9 kg/m(2) and obese ⩾30 kg/m(2). Severity of mucositis, incidence of secondary malignancy, incidence of bacteremia and median hospital length of stay did not differ among the groups. The median times to absolute neutrophil count and platelet recovery were 10 days (P=0.75) and 14 days (P=0.17), respectively. Obese patients had a lower 100-day mortality compared with other weight groups, although this did not translate into an OS benefit. OS and disease relapse were similar among the groups. Our study demonstrates that use of adjusted body weight to calculate chemotherapy doses does not negatively have an impact on outcomes in obese patients undergoing auto-SCT with BU, CY and etoposide.

MCL-1 and BCL-xL-dependent resistance to the BCL-2 inhibitor ABT-199 can be overcome by preventing PI3K/AKT/mTOR activation in lymphoid malignancies.

Overexpression of anti-apoptotic BCL-2 family members is a hallmark of many lymphoid malignancies, including chronic lymphocytic leukemia (CLL) and non-Hodgkin lymphoma (NHL) that can be targeted with small molecule inhibitors. ABT-199 is a rationally designed BCL-2 homology (BH)-3 mimetic that specifically binds to BCL-2, but not to MCL-1 and BCL-xL. Although the thrombocytopenia that occurs with navitoclax treatment has not been a problem with ABT-199, clinical trials in CLL could benefit by lowering the ABT-199 concentration through targeting other survival pathways. In this study, we investigated the mechanisms of resistance that develops to ABT-199 therapy by generating ABT-199-resistant (ABT199-R) cell lines via chronic exposure of NHL cell lines to ABT-199. Acquired resistance resulted in substantial AKT activation and upregulation of MCL-1 and BCL-xL levels that sequestered BIM. ABT199-R cells exhibited increased MCL-1 stability and failed to activate BAX in response to ABT-199. The ABT-199 acquired and inherent resistant cells were sensitized to treatment with ABT-199 by inhibitors of the PI3K, AKT, and mTOR pathways, NVP-BEZ235 and GS-1101. NVP-BEZ235, a dual inhibitor of p-AKT and mTOR, reduced MCL-1 levels causing BIM release from MCL-1 and BCL-xL, thus leading to cell death by BAX activation. The PI3Kδ inhibitor GS-1101 (idelalisib) downregulated MCL-1 and sensitized ABT199-R cells through AKT-mediated BAX activation. A genetic approach, through siRNA-mediated down-regulation of AKT, MCL-1, and BCL-xL, significantly decreased cell survival, demonstrating the importance of these cell survival factors for ABT-199 resistance. Our findings suggest a novel mechanism that modulates the expression and activity of pro-survival proteins to confer treatment resistance that could be exploited by a rational combination therapeutic regimen that could be effective for treating lymphoid malignancies.

Quality of life and outcomes in patients⩾60 years of age after allogeneic hematopoietic cell transplantation.

Hematopoietic cell transplantation (HCT) has become an established standard of care for many older patients with hematologic malignancies. The effect of transplantation on the quality of life (QOL) of older patients, however, has not been well studied. We thus analyzed QOL in patients ⩾60 undergoing an allogeneic HCT compared with patients <60 years. Prospective psychometric instruments were administered to 351 patients who underwent HCT from 2003 to 2010. Psychometric data were assessed longitudinally by validated questionnaires: Functional Assessment of Cancer Therapy-Bone Marrow Transplant (FACT-BMT), Coping Inventory and the Profile of Mood State-Short Form. Patients ⩾60 reported better social (P=0.006) and functional well-being (P=0.05) with FACT assessment, and had better total scores, (P=0.043) across all time points. When adjusted for baseline QOL scores as a covariate, social well-being remained significantly better, whereas the other scores became non-significant. With a median follow-up of 49 months, there were no significant differences in OS, relapse-free survival, relapse or chronic GVHD. This study provides further evidence that advanced age should not be a barrier in the decision to pursue allogeneic HCT. Older patients achieved comparable QOL when compared with younger patients.

BECN1 and BIM interactions with MCL-1 determine fludarabine resistance in leukemic B cells.

The purine analog fludarabine (Fd) is an essential therapeutic for chronic lymphocytic leukemia (CLL). Innate or acquired resistance to Fd is a significant clinical problem and is largely mediated by increased expression of BCL-2 family members. The antiapoptotic BCL-2 family proteins inhibit both apoptosis and autophagy, therefore, downregulation of antiapoptotic BCL-2 family proteins and enhanced autophagy must coexist in cells dying in response to an apoptosis inducing therapeutic. However, in the drug-resistant cells that have an increased dependence on antiapoptotic proteins, whether autophagy is also inhibited remains unclear. Here, we examined the role of the BCL-2 family in regulating cell death and autophagy in leukemic cell lines and their derivative isogenic Fd-resistant (FdR) cells. MCL-1 degradation following Fd treatment freed the proapoptotic effectors BIM and BECN1, thus leading to cell death-associated autophagy in Fd-sensitive cells. However, in FdR cells, low BIM expression and BECN1 sequestration by MCL-1 prevented cell death. Consistently, in sensitive cells inhibition of apoptosis using siBIM and of both the early-phase autophagy nucleation steps by siBECN1, shATG7 or 3-methyladenine and the late-phase autophagy by shLAMP2, significantly reduced Fd-induced cell death. Paradoxically, FdR cells were addicted to basal autophagy, which was dependent on AMP-activated protein kinase (AMPK) but not BECN1. Moreover, in FdR cells, inhibition of autophagy by shLAMP2, but not siBECN1, enhanced cell death. The BH3-mimetic obatoclax released BIM and BECN1 from MCL-1 in Fd-sensitive and BECN1 from MCL-1 in FdR cells, and was effective at killing both Fd-sensitive and - resistant leukemic cells, including primary CLL cells. Therefore, a differential regulation of autophagy through BECN1 and AMPK signaling in Fd-sensitive and - resistant cells determines the different possible outcomes of autophagy inhibition. These findings suggest effective means to overcome Fd resistance by induction of BIM-dependent apoptosis and activation of BECN1-dependent autophagy.

Experimental study of wet granulation in fluidized bed: impact of the binder properties on the granule morphology.

In this work, the effect of the physicochemical properties of aqueous hydroxypropyl-cellulose (HPC) binder solutions and different pharmaceutical excipients (mannitol and anhydrous CaHPO(4)) on the agglomeration kinetics and granule properties were investigated. First, a particle size distribution (PSD) analysis together with a detailed analysis of morphological properties of the excipient particles were performed. Second, the viscosity, density, surface tension and size of the spray droplets of binder solutions with different HPC concentrations were determined and wetting characteristics of the binders on the excipients were measured. Third, several fluid bed wet granulation experiments were conducted for pure excipients and their blends with binder solution of different HPC concentrations in a pilot plant Wurster granulator. The observed granule growth for different binder concentrations was a strong function of the binder concentration and the excipient solubility. For mannitol, a significant "coating" period followed by a slow granule growth was observed for the case with the diluted 5% binder. The "coating" period was significantly shorter for the 10% HPC binder and did not exist for the 15% HPC for which immediate and fast granule growth was observed. For anhydrous CaHPO(4) (trademark A-TAB), no growth was observed for the 10% HPC binder and a long coating period followed by fast granule growth was observed for the 15% HPC. Simple physically based criteria were also evaluated, which employ the morphological properties of excipients (size and surface roughness) together with physical properties of the used binder for prediction of the coating versus agglomeration regime at given flow conditions (collision velocity). As expected, a preferential coalescence and growth of the mannitol granules from the blend of mannitol+A-TAB was observed. Finally, the mechanical and morphological properties of the produced granules were measured and correlated to the HPC concentration of the binder used in the experiments. A clear correlation between the granule porosity (evaluated by X-ray tomography) and the binder concentration was found for the mannitol granules.

Vinflunine potentiates the activity of cisplatin but not 5-fluorouracil in a transplantable murine adenocarcinoma model.

BACKGROUND: Vinflunine is a novel Vinca alkaloid currently undergoing Phase II clinical trials, which have previously demonstrated anti-vascular effects in a transplantable murine colon adenocarcinoma model. Previous studies with compounds showing similar effects in combination with standard anti-cancer agents have demonstrated an improved efficacy relative to the standard agents. MATERIALS AND METHODS: In this study the synergistic effects of administering vinflunine in combination with either Cisplatin (CPL) or 5-fluorouracil (5-FU) were investigated in a well-differentiated transplantable murine colon adenocarcinoma model (MAC 29). RESULTS: Vinflunine significantly potentiated the anti-tumour effects of CPL, but had little effect in combination with 5-FU. Using Hoescht 33342 dye labelling of the functional vasculature, clear evidence of vascular shutdown was seen for treatment groups including vinflunine. CONCLUSION: These data demonstrate that the combination of vinflunine and CPL has significant preclinical anti-tumour activity against a transplantable murine adenocarcinoma model that is related to the anti-vascular effects of vinflunine.

In vivo antitumor activity of F 11782, a non-intercalating dual catalytic inhibitor of topoisomerases I and II, against a panel of human tumor xenografts.

The marked in vivo antitumor activity of F 11782 against murine experimental tumors (Kruczynski et al., Br J Cancer 83: 1516-24, 2000) has now been confirmed in a panel of human tumor xenografts. Using an intermittent schedule of six administrations over 2 weeks, F 11782 showed major activity in four of eight xenograft models. Excellent activity was noted versus the CAKI-1 (renal) model, with regressions at the two highest doses, and marked activity against DLD-1 (colon) xenografts, also resulting in regressions at the MTD. Marked antitumor activity was also observed against DU 145 (prostate) and GLC4 (small-cell lung) tumors. At optimal doses, significant T/C values ranged from 3 to 29%, with significant growth delays of 1.5-5.6, without major body weight loss. This tumor growth inhibition induced by F 11782 was sustained with time for > or = 6 weeks post implant. In contrast, no real activity was recorded against NCI-H460 (non small-cell lung) tumors and only minor responses, with optimal T/C values of < 42%, noted in the rapidly proliferating SF-295 (CNS) and LOX IMVI (melanoma) xenografts or the chemo-refractory LoVo (colon) model. Overall, this study showing a 50% response rate with definite antitumor activity across a broad spectrum, coupled with its unique mechanistic profile, has prompted the further development of F 11782.

Characterization of cell death induced by vinflunine, the most recent Vinca alkaloid in clinical development.

Vinflunine, the most recent Vinca alkaloid in clinical development, demonstrated superior antitumour activity to other Vincas in preclinical tumour models. This study aimed to define its molecular mechanisms of cell killing in both parental sensitive and vinflunine-resistant P388 leukaemia cells. Vinflunine treatment of these cells resulted in apoptosis characterized by DNA fragmentation and proteolytic cleavage of poly-(ADP-ribose) polymerase. Apoptosis-inducing concentrations of vinflunine caused c-Jun N-terminal kinase 1 stimulation, as well as caspases-3/7 activation. This activation of caspases and the induction of apoptosis could be inhibited by the caspase inhibitor acetyl-Asp-Glu-Val-Asp-aldehyde. Interestingly, the apoptosis signal triggered by vinflunine in these P388 cells was not mediated through Bcl-2 phosphorylation. In addition, when vinflunine resistance was developed in P388 cells, it was associated with resistance to vinflunine-induced apoptosis, as reflected by a loss of capacity to induce DNA fragmentation and PARP degradation, and characterized by increased levels of Bcl-2 and Bfl-1/A1. Therefore, these data indirectly implicate Bcl-2 and Bfl-1/A1 in vinflunine-induced cell death mechanisms.

Vinflunine, the latest Vinca alkaloid in clinical development. A review of its preclinical anticancer properties.

Vinflunine is a new Vinca alkaloid uniquely fluorinated, by the use of superacid chemistry, in a little exploited region of the catharanthine moiety. In vitro investigations have confirmed the mitotic-arresting and tubulin-interacting properties of vinflunine shared by other Vinca alkaloids. However, differences in terms of the inhibitory effects of vinflunine on microtubules dynamics and its tubulin binding affinities have been identified which appear to distinguish it from the other Vinca alkaloids. Vinflunine induced smaller spirals with a shorter relaxation time, effects, which might be associated with reduced neurotoxicity. Studies investigating the in vitro cytotoxicity of vinflunine in combination therapy have revealed a high level of synergy when vinflunine was combined with either cisplatin, mitomycin C, doxorubicin or 5-fluorouracil. Furthermore, although vinflunine appears to participate in P-glycoprotein-mediated drug resistance mechanisms, it has proved only a weak substrate for this protein and a far less potent inducer of resistance than vinorelbine. Vinflunine was identified in preclinical studies as having marked antitumour activity in vivo against a large panel of experimental tumour models, with tumour regressions being recorded in human renal and small cell lung cancer tumour xenografts. Overall its level of activity was superior to that of vinorelbine in many of the experimental models used. Interestingly, an in vivo study using a well vascularised adenocarcinoma of the colon has suggested that vinflunine mediates its antitumour activity at least in part via an antivascular mechanism, even at sub-cytotoxic doses. Therefore, these data provide a favourable preclinical profile for vinflunine, supporting its promising candidacy for clinical development. Phase I evaluations of vinflunine have been completed in Europe and phase II clinical trials are now ongoing.

Markedly diminished drug resistance-inducing properties of vinflunine (20',20'-difluoro-3',4'-dihydrovinorelbine) relative to vinorelbine, identified in murine and human tumour cells in vivo and in vitro.

PURPOSE: Vinflunine (VFL) is a novel Vinca alkaloid with markedly superior experimental in vivo antitumour activity to its parent molecule, vinorelbine (Navelbine, NVB), against a panel of murine and human tumours. The aim of this study was to establish whether there are differences in the rate and extent of development of resistance, both in vivo and in vitro, to these two newer Vinca alkaloids under identical selection conditions. METHODS: Using P388 leukaemia cells in vivo, it was evident that VFL induced drug resistance far less readily than NVB, as shown by the number of passages required to select for total resistance. Under in vitro conditions, using A549 human lung carcinoma cells, it was also clearly shown by drug sensitivity determinations that VFL was a less-potent inducer of drug resistance than NVB. Resistance resulting from either in vivo or in vitro selection was associated with a classic multidrug resistance profile. Further characterization of the drug-resistance phenotype of the most highly resistant A549 sublines showed that the level of total beta-tubulin expression appeared to be modified exclusively in the NVB-resistant cells. CONCLUSION: The clear demonstration that resistance to VFL developed far less readily than resistance to NVB both in vivo and in vitro may have potential clinical implications.