Venetoclax-obinutuzumab for previously untreated chronic lymphocytic leukemia: 6-year results of the randomized phase 3 CLL14 study.

ABSTRACT: In the CLL14 study, patients with previously untreated chronic lymphocytic leukemia (CLL) and coexisting conditions were randomized to 12 cycles of venetoclax-obinutuzumab (Ven-Obi, n = 216) or chlorambucil-obinutuzumab (Clb-Obi, n = 216). Progression-free survival (PFS) was the primary end point. Key secondary end points included time-to-next-treatment (TTNT), rates of undetectable minimal residual disease (uMRD), overall survival (OS), and rates of adverse events. Patient reported outcomes of time until definitive deterioration (TUDD) in quality of life (QoL) were analyzed. At a median observation time of 76.4 months, PFS remained superior for Ven-Obi compared with Clb-Obi (median, 76.2 vs 36.4 months; hazard ratio [HR], 0.40; 95% confidence interval [CI], 0.31-0.52; P < .0001). Likewise, TTNT was longer after Ven-Obi (6-year TTNT, 65.2% vs 37.1%; HR, 0.44; 95% CI, 0.33-0.58; P < .0001). In the Ven-Obi arm, presence of del(17p), unmutated immunoglobulin heavy-chain variable region, and lymph node size of ≥5 cm were independent prognostic factors for shorter PFS. The 6-year OS rate was 78.7% in the Ven-Obi and 69.2% in the Clb-Obi arm (HR, 0.69; 95% CI, 0.48-1.01; P = .052). A significantly longer TUDD in global health status/QoL was observed in the Ven-Obi than in the Clb-Obi arm (median, 82.1 vs 65.1 months; HR, 0.70; 95% CI, 0.51-0.97). Follow-up-adjusted second primary malignancies incidence rates were 2.3 and 1.4 per 1000 patient-months in the Ven-Obi and Clb-Obi arm, respectively. The sustained long-term survival and QoL benefits support the use of 1-year fixed-duration Ven-Obi in CLL. This trial was registered at www.ClinicalTrials.gov as #NCT02242942.

Evaluation of the novel therapeutic anti-CCR7 antibody CAP-100 as an add-on therapy in chronic lymphocytic leukemia patients receiving venetoclax.

The Bruton's tyrosine kinase inhibitor ibrutinib and the B-cell lymphoma 2 anti-apoptotic protein inhibitor venetoclax provide high response rates in chronic lymphocytic leukemia (CLL). However, there is a growing number of patients that relapse after treatment or show refractory disease, thus new targets and agents are still needed. We have previously reported the chemokine receptor CCR7 as a relevant deregulated target in CLL and have developed CAP-100, a novel therapeutic anti-CCR7 antibody that is under evaluation for relapse/refractory CLL (NCT04704323). While CCR7 expression has been shown to be down-modulated in CLL patients treated with ibrutinib, whether venetoclax acts in a similar manner remains unaddressed. Here, we aimed to document the impact of venetoclax on CCR7 expression in CLL cells, as well as on the pre-clinical activity of CAP-100. To this end, we addressed CCR7 expression by flow cytometry and the antibody efficacy by means of in vitro chemotactic and antibody-dependent cell-mediated cytotoxicity (ADCC) assays. Our data indicate that venetoclax treatment did not significantly modify CCR7 expression pattern nor CAP-100 mechanisms of action. Together, these findings support CAP-100 as an adjuvant therapy to venetoclax that may introduce additional modes of action in CLL therapy.

Effect of ibrutinib on CCR7 expression and functionality in chronic lymphocytic leukemia and its implication for the activity of CAP-100, a novel therapeutic anti-CCR7 antibody.

CAP-100 is a novel therapeutic antibody directed against the ligand binding site of human CCR7. This chemokine receptor is overexpressed in chronic lymphocytic leukemia (CLL) and orchestrates the homing of CLL cells into the lymph node. Previous studies, on a very limited number of samples, hypothesized that the Bruton's tyrosine kinase inhibitor (BTKi) ibrutinib might induce loss of surface CCR7 levels in CLL cells. CAP-100 will be evaluated in clinical trials as a therapy for relapse/refractory CLL patients, who have received at least two systemic therapies (NCT04704323). As nowadays many relapse/refractory CLL patients will have received ibrutinib as a prior therapy, we aimed to investigate in a large cohort of CLL patients the impact of this BTKi on CCR7 expression and functionality as well as on the therapeutic activity of CAP-100. Our data confirm that ibrutinib moderately down-regulates the very high expression of CCR7 in CLL cells but has no apparent effect on CCR7-induced chemotaxis. Moreover, CLL cells are perfectly targetable by CAP-100 which led to a complete inhibition of CCR7-mediated migration and induced strong target cell killing through antibody-dependent cell-mediated cytotoxicity, irrespective of previous or contemporary ibrutinib administration. Together, these results validate the therapeutic utility of CAP-100 as a next-line single-agent therapy for CLL patients who failed to ibrutinib and confirm that CAP-100 and ibrutinib have complementary non-overlapping mechanisms of action, potentially allowing for combination therapy.

Clinical outcome and prognostic factors of patients with Richter syndrome: real-world study of the Spanish Chronic Lymphocytic Leukemia Study Group (GELLC).

Richter syndrome (RS) is an uncommon evolution of chronic lymphocytic leukaemia (CLL) with a dismal prognosis. Clinical-biological features predicting outcome and best therapeutic approach for these patients remain to be established. In this study, 128 patients with RS, including 112 diffuse large B-cell lymphoma (DLBCL)-type RS, 15 Hodgkin lymphoma (HL)-type RS, and one plasmablastic lymphoma, were identified in 11 centres of the Spanish CLL Study Group (GELLC). The median overall survival (OS) was 5·9 months for DLBCL-type RS and 30·8 months for HL-type RS. Eastern Cooperative Oncology Group Performance Status, haemoglobin level, platelet count, serum lactate dehydrogenase and ß2-microglobulin levels, tumour protein p53 (TP53) abnormalities in the CLL clone concomitant to RS, number of prior therapies, and clonal relationship between CLL and RS, were associated with OS in patients with DLBCL-type RS. A platelet count of <100 × 109 /l, prior CLL therapy (0 vs. ≥1), and presence of TP53 alterations maintained an independent prognostic impact in the multivariate analysis. Patients without any of these factors had a better clinical outcome, with a median OS of 75·3 months, while patients with one or two or more of these factors presented a median OS of 25·5 and 3 months, respectively. Although OS of patients with RS is generally poor, a proportion of patients achieved prolonged survival. Treatment of RS remains a medical need, and further therapeutic approaches with novel therapies are warranted.

Frontline treatment with the combination obinutuzumab ± chlorambucil for chronic lymphocytic leukemia outside clinical trials: Results of a multinational, multicenter study by ERIC and the Israeli CLL study group.

In recent years, considerable progress has been made in frontline therapy for elderly/physically unfit patients with CLL. The combination of obinutuzumab and chlorambucil (O-Clb) has been shown to prolong progression free survival (PFS, median PFS-31.5 months) and overall survival (OS) compared to chlorambucil alone. More recently, obinutuzumab given in combination with either ibrutinib or venetoclax improved PFS but not OS when compared to O-Clb. In this retrospective multinational, multicenter co-operative study, we evaluated the efficacy and safety of frontline treatment with O ± Clb in unfit patients with CLL, in a "real-world" setting. Patients with documented del (17p13.1)/TP53 mutation were excluded. A total of 437 patients (median age, 75.9 years; median CIRS score, 8; median creatinine clearance, 61.1 mL/min) were included. The clinical overall response rate was 80.3% (clinical complete and partial responses in 38.7% and 41.6% of patients, respectively). Median observation time was 14.1 months and estimated median PFS was 27.6 months (95% CI, 24.2-31.0). In a multivariate analysis, high-risk disease [del (11q22.3) and/or IGHV-unmutated], lymph nodes of diameter > 5 cm, obinutuzumab monotherapy and reduced cumulative dose of obinutuzumab, were all independently associated with shorter PFS. The median OS has not yet been reached and estimated 2-year OS is 88%. In conclusion, in a "real-world" setting, frontline treatment with O-Clb achieves PFS comparable to that reported in clinical trials. Inferior outcomes were noted in patients with del (11q22.3) and/or unmutated IGHV and those treated with obinutuzumab-monotherapy. Thus, O-Clb can be still considered as legitimate frontline therapy for unfit CLL patients with low-risk disease.

Systemic Exposure of Rituximab Increased by Ibrutinib: Pharmacokinetic Results and Modeling Based on the HELIOS Trial.

INTRODUCTION: In the HELIOS trial, bendamustine/rituximab (BR) plus ibrutinib (BR-I) improved disease outcomes versus BR plus placebo in previously treated chronic lymphocytic leukemia/small lymphocytic lymphoma. Here, we describe the pharmacokinetic (PK) observations, along with modeling to further explore the interaction between ibrutinib and rituximab. METHODS: 578 subjects were randomized to ibrutinib or placebo with BR (6 cycles). Ibrutinib PK samples and tumor measurements were obtained from all subjects; a subset was evaluated for bendamustine and rituximab PK. Population rituximab PK was assessed using nonlinear mixed-effects modeling. RESULTS: Dose-normalized plasma concentration-time bendamustine data were comparable between the arms. Systemic rituximab exposure was higher with BR-I versus BR; mean trough serum concentrations were 2- to 3-fold higher in the first three cycles and 1.2- to 1.7-fold higher subsequently. No relevant safety differences were observed. In the modeling, including treatment arm as a categorical covariate and tumor burden as a continuous time-varying covariate on overall rituximab clearance significantly improved fitting of the data. CONCLUSIONS: BR-I led to higher dose-normalized systemic rituximab exposure versus BR and more rapid steady-state achievement. The modeling data suggest that rituximab disposition is, at least in part, target mediated. Determining the clinical significance of these findings requires further assessments. TRIAL REGISTRATION: This study is registered at https://clinicaltrials.gov/ct2/show/NCT01611090 .

Randomized phase 2 study of otlertuzumab and bendamustine versus bendamustine in patients with relapsed chronic lymphocytic leukaemia.

Otlertuzumab (TRU-016) is a humanized anti-CD37 protein therapeutic that triggers direct caspase-independent apoptosis of malignant B cells and induces antibody-dependent cell-mediated cytotoxicity. Patients with relapsed chronic lymphocytic leukaemia (CLL) received either otlertuzumab (20 mg/kg) weekly by IV infusion for two 28-day cycles then every 14 days for four 28-day cycles and IV bendamustine (70 mg/m2 ) on Days 1 and 2 of each cycle for up to six 28-day cycles or bendamustine alone. Thirty-two patients were treated with otlertuzumab and bendamustine and 33 with bendamustine alone. Overall response rate according to the International Workshop on Chronic Lymphocytic Leukaemia criteria was 69% in the otlertuzumab and bendamustine arm and 39% in the bendamustine alone arm (P = 0·025). Median progression-free survival (PFS) was 15·9 months in the otlertuzumab and bendamustine arm and 10·2 months in the bendamustine alone arm (P = 0·0192). There was a higher incidence of pyrexia (34% vs. 12%) and neutropenia (59% vs. 39%) with the combination but this did not result in a higher incidence of severe (grade 3/4) infections (13% vs. 27%). This combination significantly increased the response rate and prolonged the PFS over single agent bendamustine in patients with relapsed or refractory CLL.

Ibrutinib combined with bendamustine and rituximab compared with placebo, bendamustine, and rituximab for previously treated chronic lymphocytic leukaemia or small lymphocytic lymphoma (HELIOS): a randomised, double-blind, phase 3 study.

BACKGROUND: Most patients with chronic lymphocytic leukaemia or small lymphocytic lymphoma relapse after initial therapy. Bendamustine plus rituximab is often used in the relapsed or refractory setting. We assessed the efficacy and safety of adding ibrutinib, an oral covalent inhibitor of Bruton's tyrosine kinase (BTK), to bendamustine plus rituximab in patients with previously treated chronic lymphocytic leukaemia or small lymphocytic lymphoma. METHODS: The HELIOS trial was an international, double-blind, placebo-controlled, phase 3 study in adult patients (≥18 years of age) who had active chronic lymphocytic leukaemia or small lymphocytic lymphoma with measurable lymph node disease (>1·5 cm) by CT scan, and had relapsed or refractory disease following one or more previous lines of systemic therapy consisting of at least two cycles of a chemotherapy-containing regimen, an Eastern Cooperative Oncology Group (ECOG) performance status of 0-1, and adequate bone marrow, liver, and kidney function. Patients with del(17p) were excluded because of known poor response to bendamustine plus rituximab. Patients who had received previous treatment with ibrutinib or other BTK inhibitors, refractory disease or relapse within 24 months with a previous bendamustine-containing regimen, or haemopoietic stem-cell transplant were also excluded. Patients were randomly assigned (1:1) by a web-based system to receive bendamustine plus rituximab given in cycles of 4 weeks' duration (bendamustine: 70 mg/m(2) intravenously on days 2-3 in cycle 1, and days 1-2 in cycles 2-6; rituximab: 375 mg/m(2) on day 1 of cycle 1, and 500 mg/m(2) on day 1 of cycles 2-6 for a maximum of six cycles) with either ibrutinib (420 mg daily orally) or placebo until disease progression or unacceptable toxicity. Patients were stratified according to whether they were refractory to purine analogues and by number of previous lines of therapy. The primary endpoint was independent review committee (IRC)-assessed progression-free survival. Crossover to ibrutinib was permitted for patients in the placebo group with IRC-confirmed disease progression. Analysis was by intention-to-treat and is continuing for further long-term follow-up. The trial is registered with ClinicalTrials.gov, number NCT01611090. FINDINGS: Between Sept 19, 2012, and Jan 21, 2014, 578 eligible patients were randomly assigned to ibrutinib or placebo in combination with bendamustine plus rituximab (289 in each group). The primary endpoint was met at the preplanned interim analysis (March 10, 2015). At a median follow-up of 17 months (IQR 13·7-20·7), progression-free survival was significantly improved in the ibrutinib group compared with the placebo group (not reached in the ibrutinib group (95% CI not evaluable) vs 13·3 months (11·3-13·9) in the placebo group (hazard ratio [HR] 0·203, 95% CI 0·150-0·276; p<0·0001). IRC-assessed progression-free survival at 18 months was 79% (95% CI 73-83) in the ibrutinib group and 24% (18-31) in the placebo group (HR 0·203, 95% CI 0·150-0·276; p<0·0001). The most frequent all-grade adverse events were neutropenia and nausea. 222 (77%) of 287 patients in the ibrutinib group and 212 (74%) of 287 patients in the placebo group reported grade 3-4 events; the most common grade 3-4 adverse events in both groups were neutropenia (154 [54%] in the ibrutinib group vs 145 [51%] in the placebo group) and thrombocytopenia (43 [15%] in each group). A safety profile similar to that previously reported with ibrutinib and bendamustine plus rituximab individually was noted. INTERPRETATION: In patients eligible for bendamustine plus rituximab, the addition of ibrutinib to this regimen results in significant improvements in outcome with no new safety signals identified from the combination and a manageable safety profile. FUNDING: Janssen Research & Development.

PTK2 expression and immunochemotherapy outcome in chronic lymphocytic leukemia.

Addition of rituximab (R) to fludarabine and cyclophosphamide (FC) has significantly improved patient outcomes in chronic lymphocytic leukemia (CLL). Whether baseline gene expression can identify patients who will benefit from immunochemotherapy over chemotherapy alone has not been determined. We assessed genome-wide expression of 300 pretreatment specimens from a subset of 552 patients in REACH, a study of FC or R-FC in relapsed CLL. An independent test set was derived from 282 pretreatment specimens from CLL8, a study of FC or R-FC in treatment-naïve patients. Genes specific for benefit from R-FC were determined by assessing treatment-gene interactions in Cox proportional hazards models. REACH patients with higher pretreatment protein tyrosine kinase 2 (PTK2) messenger RNA levels derived greater benefit from R-FC, with significant improvements in progression-free survival, independent of known prognostic factors in a multivariate model. Examination of PTK2 gene expression in CLL8 patients yielded similar results. Furthermore, PTK2 inhibition blunted R-dependent cell death in vitro. This retrospective analysis from 2 independent trials revealed that increased PTK2 expression is associated with improved outcomes for CLL patients treated with R-FC vs FC. PTK2 expression may be a useful biomarker for patient selection in future trials. These trials were registered at www.clinicaltrials.gov as #NCT00090051 (REACH) and #NCT00281918 (CLL8).

Recommendations on the clinical use of bendamustine in lymphoproliferative syndromes and multiple myeloma.

Bendamustine is an increasingly used hybrid alkylating agent that is active in lymphoid neoplasias via a novel mechanism of action. There are some pending questions about its use in clinical practice because of its developmental features. A consensus panel of several leading Spanish hematologists with broad experience in the clinical use of bendamustine has established recommendations for the management and treatment of hematological patients with bendamustine based on available clinical data and the experience of the participants. These recommendations address the dose and treatment regimen for different clinical indications, the management of toxicity, and support therapy. This article contains the conclusions of this consensus panel, which are intended to serve as guidelines for the use of bendamustine.

Preclinical activity of anti-CCR7 immunotherapy in patients with high-risk chronic lymphocytic leukemia.

Chronic lymphocytic leukemia (CLL) with deletions of the p53 locus on chromosome 17 and/or refractory to fludarabine chemoimmunotherapy remains a major clinical problem with few therapeutic options. Currently, these types of CLL are treated with approaches that do not target the p53 pathway, such as small molecules and monoclonal antibodies (mAb). We have previously postulated anti-CCR7 mAb therapy as a novel CLL treatment. In the present study, we evaluated the in vitro efficacy of anti-CCR7 mAb as a single agent in CLL patients with high-risk cytogenetics and/or refractory to fludarabine, by measuring CCR7 surface expression and complement-dependent cytotoxicity. Our results demonstrate that CCR7 is highly expressed in challenging and heavily treated CLL patients. In addition, the complement-mediated mechanism of action of this mAb effectively eradicates CLL cells while sparing subsets of T cells in these patients. Moreover, this mAb outperformed the activity of alemtuzumab, the mAb with the highest efficacy in these groups. Finally, in vitro activity was also demonstrated in patients with a disease refractory to both fludarabine and alemtuzumab, and patients harboring 11q22 deletion. Our results propose that anti-CCR7 mAb is an effective and promising future treatment in high-risk CLL.

Interobserver variance in myelodysplastic syndromes with less than 5 % bone marrow blasts: unilineage vs. multilineage dysplasia and reproducibility of the threshold of 2 % blasts.

Previous studies have shown the reproducibility of the 2008 World Health Organization (WHO) classification in myelodysplastic syndromes (MDS), especially when multilineage dysplasia or excess of blasts are present. However, there are few data regarding the reproducibility of MDS with unilineage dysplasia. The revised International Prognostic Scoring System R-IPSS described two new morphological categories, distinguishing bone marrow (BM) blast cell count between 0-2 % and >2- < 5 %. This distinction is critical for establishing prognosis, but the reproducibility of this threshold is still not demonstrated. The objectives of our study were to explore the reliability of the 2008 WHO classification, regarding unilineage vs. multilineage dysplasia, by reviewing 110 cases previously diagnosed with MDS, and to study whether the threshold of ≤2 % BM blasts is reproducible among different observers. We used the same methodology as in our previous paper [Font et al. (2013) Ann Hematol 92:19-24], by encouraging investigators to include patients with <5 % BM blasts. Samples were collected from 11 hospitals and were evaluated by 11 morphologists. Each observer evaluated 20 samples, and each sample was analyzed independently by two morphologists. Discordance was observed in 36/108 suitable cases (33 %, kappa test 0.503). Diagnosis of MDS with unilineage dysplasia (refractory cytopenia with unilineage dysplasia (RCUD), refractory anemia with ring sideroblasts (RARS) or unclassifiable MDS) was assessed in 33 patients, by either of the two observers. We combined this series with the cases with RCUD or RARS included in our 2013 paper, thus obtaining 50 cases with unilineage dysplasia by at least one of the observers. The whole series showed very low agreement regarding RCUD (5/23, 21 %) and RARS (5/28, 18 %). Regarding BM blast count, the threshold of ≤2 % was not reproducible (discordance rate 32/108 cases, kappa test 0.277). Our study shows that among MDS WHO 2008 categories, interobserver discordance seems to be high in cases with unilineage dysplasia. We also illustrate that the threshold of ≤2 % BM blasts as settled by the R-IPSS may be not easy to reproduce by morphologists in real practice.

Rozrolimupab, a mixture of 25 recombinant human monoclonal RhD antibodies, in the treatment of primary immune thrombocytopenia.

Rozrolimupab, a recombinant mixture of 25 fully human RhD-specific monoclonal antibodies, represents a new class of recombinant human antibody mixtures. In a phase 1 or 2 dose escalation study, RhD(+) patients (61 subjects) with primary immune thrombocytopenia received a single intravenous dose of rozrolimupab ranging from 75 to 300 µg/kg. The primary outcome was the occurrence of adverse events. The principal secondary outcome was the effect on platelet levels 7 days after the treatment. The most common adverse events were headache and pyrexia, mostly mild, and reported in 20% and 13% of the patients, respectively, without dose relationship. Rozrolimupab caused an expected transient reduction of hemoglobin concentration in the majority of the patients. At the dose of 300 µg/kg platelet responses, defined as platelet count ≥ 30 × 10(9)/L and an increase in platelet count by > 20 × 10(9)/L from baseline were observed after 72 hours and persisted for at least 7 days in 8 of 13 patients (62%). Platelet responses were observed within 24 hours in 23% of patients and lasted for a median of 14 days. Rozrolimupab was well tolerated and elicited rapid platelet responses in patients with immune thrombocytopenia and may be a useful alternative to plasma-derived products. This trial is registered at www.clinicaltrials.gov as #NCT00718692.

Real-World Evidence on the Clinical Characteristics and Management of Patients with Chronic Lymphocytic Leukemia in Spain Using Natural Language Processing: The SRealCLL Study.

The SRealCLL study aimed to obtain real-world evidence on the clinical characteristics and treatment patterns of patients with chronic lymphocytic leukemia (CLL) using natural language processing (NLP). Electronic health records (EHRs) from seven Spanish hospitals (January 2016-December 2018) were analyzed using EHRead® technology, based on NLP and machine learning. A total of 534 CLL patients were assessed. No treatment was detected in 270 (50.6%) patients (watch-and-wait, W&W). First-line (1L) treatment was identified in 230 (43.1%) patients and relapsed/refractory (2L) treatment was identified in 58 (10.9%). The median age ranged from 71 to 75 years, with a uniform male predominance (54.8-63.8%). The main comorbidities included hypertension (W&W: 35.6%; 1L: 38.3%; 2L: 39.7%), diabetes mellitus (W&W: 24.4%; 1L: 24.3%; 2L: 31%), cardiac arrhythmia (W&W: 16.7%; 1L: 17.8%; 2L: 17.2%), heart failure (W&W 16.3%, 1L 17.4%, 2L 17.2%), and dyslipidemia (W&W: 13.7%; 1L: 18.7%; 2L: 19.0%). The most common antineoplastic treatment was ibrutinib in 1L (64.8%) and 2L (62.1%), followed by bendamustine + rituximab (12.6%), obinutuzumab + chlorambucil (5.2%), rituximab + chlorambucil (4.8%), and idelalisib + rituximab (3.9%) in 1L and venetoclax (15.5%), idelalisib + rituximab (6.9%), bendamustine + rituximab (3.5%), and venetoclax + rituximab (3.5%) in 2L. This study expands the information available on patients with CLL in Spain, describing the diversity in patient characteristics and therapeutic approaches in clinical practice.

Chronic lymphocytic leukaemia with 17p deletion: a retrospective analysis of prognostic factors and therapy results.

Patients with chronic lymphocytic leukaemia (CLL) whose tumour cells harbour a 17p deletion (17p-) are universally considered to have a poor prognosis. The deletion can be detected at diagnosis or during the evolution of the disease, particularly in patients who have received chemotherapy. We sought to evaluate the natural history of patients with 17p- CLL, identify predictive factors within this prognostic subgroup, and evaluate the results of different therapeutic approaches. Data from 294 patients with 17p- CLL followed up at 20 different institutions was retrospectively collected and analysed. Median age was 68 (range 27-98) years at the time of fluorescence in situ hybridization analysis. After 17p- documentation, 52% received treatment, achieving an overall response rate of 50%. Median overall survival was 41 months, and was significantly shorter in patients with elevated beta(2)-microglobulin concentration (P < 0·001), B symptoms (P = 0·016), higher percentage of cells with deletion (P < 0·001), and acquired deletions (P = 0·012). These findings suggest that patients with 17p- CLL have a variable prognosis that can be refined using simple clinical and laboratory features, including 17p- clone size, beta2-microglobulin concentration, presence of B symptoms and type of deletion (de novo versus acquired).

Bendamustine compared with chlorambucil in previously untreated patients with chronic lymphocytic leukaemia: updated results of a randomized phase III trial.

The efficacy of bendamustine versus chlorambucil in a phase III trial of previously untreated patients with Binet stage B/C chronic lymphocytic leukaemia (CLL) was re-evaluated after a median observation time of 54 months in May 2010. Overall survival (OS) was analysed for the first time. At follow-up, investigator-assessed complete response (CR) rate (21·0% vs 10·8%), median progression-free survival (21·2 vs 8·8 months; P < 0·0001; hazard ratio 2·83) and time to next treatment (31·7 vs 10·1 months; P < 0·0001) were improved for bendamustine over chlorambucil. OS was not different between groups for all patients or those ≤65 years, >65 years, responders and non-responders. However, patients with objective response or a CR experienced a significantly longer OS than non-responders or those without a CR. Significantly more patients on chlorambucil progressed to second/further lines of treatment compared with those on bendamustine (78·3% vs 63·6%; P = 0·004). The benefits of bendamustine over chlorambucil were achieved without reducing quality of life. In conclusion, bendamustine is significantly more effective than chlorambucil in previously untreated CLL patients, with the achievement of a CR or objective response appearing to prolong OS. Bendamustine should be considered as a preferred first-line option over chlorambucil for CLL patients ineligible for fludarabine, cyclophosphamide and rituximab.

Effect of FCGR2A and FCGR3A variants on CLL outcome.

Polymorphisms of activating Fc-γ receptors (FCGRs) on natural killer cells and macrophages result in variable affinity for immunoglobulin G1 monoclonal antibodies and subsequently modulate antibody-dependent cellular cytotoxicity (ADCC) activity. Whether single-nucleotide polymorphisms of FCGRs correlate with survival of chronic lymphocytic leukemia (CLL) patients treated with a monoclonal antibody containing regimen is unclear. We assessed the FCGR3A and FCGR2A genotype of patients enrolled in the REACH trial, where patients received fludarabine and cyclophosphamide (FC) or rituximab plus FC (R-FC). FCGR3A and FCGR2A polymorphisms did not demonstrate prognostic significance in the FC arm (P = .42 and P = .64, respectively) or R-FC arm (P = .41 and P = .88, respectively) with respect to progression free survival. Patients with intermediate affinity genotypes (FV and HR) benefited significantly from addition of rituximab (hazard ratio = 0.55 [0.37-0.8 CI]; P = .0017 and hazard ratio = 0.63 [0.44-0.9 CI]; P = .011, respectively). Similar benefit was suggested for patients with high- affinity VV and HH (hazard ratio = 0.86 [0.4-1.84 CI]; P = .7 and hazard ratio = 0.7 [0.41-1.18 CI]; P = .18, respectively) and low-affinity FF and RR (hazard ratio = 0.85 [0.56-1.29 CI]; P = .44 and hazard ratio = 0.82 [0.47-1.42 CI]; P = .48, respectively). Overall, our results suggest that FCGR2A and FCGR3A polymorphisms do not significantly influence the outcomes of relapsed or refractory CLL patients treated with FC or the monoclonal antibody regimen R-FC.

Ibrutinib Does Not Impact CCR7-Mediated Homeostatic Migration in T-Cells from Chronic Lymphocytic Leukemia Patients.

Bruton's tyrosine kinase inhibitor ibrutinib has significantly changed treatment landscape in chronic lymphocytic leukemia (CLL). Growing evidence supports ibrutinib to work beyond the effect on tumor cells by means of, for example, restoring functionality of the T-cell compartment and increasing circulating T-cell numbers. Recent evidence suggests T-cell enhanced expansion, rather than increased egress from secondary lymphoid organs (SLO), as a root cause for ibrutinib-induced lymphocytosis. However, whether the latter physiological change is also a consequence of a forced retention in blood remains undisclosed. Since CCR7 is the main chemokine receptor taking over the homing of T-cells from peripheral compartments to lymph nodes and other SLO, we aimed to investigate the impact of ibrutinib on CCR7 functionality in T-cells. To this end, we documented receptor expression in T-cells from a large cohort of ibrutinib-treated CLL patients, and performed different in vivo and in vitro migration models. Overall, our data confirm that CCR7 expression or receptor-mediated migration in CLL T-cells is not affected by ibrutinib. Furthermore, it does not modulate CCR7-driven homing nor nodal interstitial migration. Together, our results support that ibrutinib-induced CLL T-cell accumulation in the blood stream is not derived from an impairment of CCR7-driven recirculation between the SLO and bloodstream, and therefore T-cell expansion is the most plausible cause.

Targeting cancer homing into the lymph node with a novel anti-CCR7 therapeutic antibody: the paradigm of CLL.

Lymph node (LN) is a key tissue in the pathophysiology of mature blood cancers, especially for chronic lymphocytic leukemia (CLL). Within the multiple de-regulated pathways affecting CLL homeostasis, the CC-chemokine receptor 7 (CCR7) grants homing of CLL cells into the LN where protective environments foster tumor progression. To cover the lack of specific therapies targeting the CCR7-dependence of CLL to enter into the LN, and aiming to displace the disease from LN, we generated CAP-100, an antibody that specifically binds to hCCR7 and neutralizes its ligand-binding site and signaling. In various in vitro and in vivo preclinical models CAP-100 strongly inhibited CCR7-induced migration, extravasation, homing, and survival in CLL samples. Moreover, it triggered potent tumor cell killing, mediated by host immune mechanisms, and was effective in xenograft models of high-risk disease. Additionally, CAP-100 showed a favorable toxicity profile on relevant hematopoietic subsets. Our results validated CAP-100 as a novel therapeutic tool to prevent the access of CLL cells, and other neoplasia with nodal-dependence, into the LN niches, thus hitting a central hub in the pathogenesis of cancer. The first-in-human clinical trial (NCT04704323), which will evaluate this novel therapeutic approach in CLL patients, is pending.

Real-World Characteristics and Outcome of Patients Treated With Single-Agent Ibrutinib for Chronic Lymphocytic Leukemia in Spain (IBRORS-LLC Study).

BACKGROUND: Ibrutinib demonstrated remarkable efficacy and favorable tolerability in patients with untreated or relapsed/refractory (R/R) chronic lymphocytic leukemia (CLL), including those with high-risk genetic alterations. The IBRORS-CLL study assessed the characteristics, clinical management and outcome of CLL patients receiving ibrutinib in routine clinical practice in Spain. PATIENTS: Observational, retrospective, multicenter study in CLL patients who started single-agent ibrutinib as first-line treatment or at first or second relapse between January 2016 and January 2019. RESULTS: A total of 269 patients were included (median age: 70.9 years; cardiovascular comorbidity: 55.4%, including hypertension [47.6%] and atrial fibrillation [AF] [7.1%]). Overall, 96.7% and 69% of patients underwent molecular testing for del(17p)/TP53 mutation and IGHV mutation status. High-risk genetic features included unmutated IGHV (79%) and del(17p)/TP53 mutation (first-line: 66.3%; second-line: 23.1%). Overall, 84 (31.2%) patients received ibrutinib as first-line treatment, and it was used as second- and third-line therapy in 121 (45.0%) and 64 (23.8%) patients. The median progression-free survival and overall survival were not reached irrespective of del(17p)/TP53, or unmutated IGHV. Common grade ≥3 adverse events were infections (12.2%) and bleeding (3%). Grade ≥3 AF occurred in 1.5% of patients. CONCLUSION: This real-world study shows that single-agent ibrutinib is an effective therapy for CLL, regardless of age and high-risk molecular features, consistent with clinical trials. Additionally, single-agent ibrutinib was well tolerated, with a low rate of cardiovascular events. This study also emphasized a high molecular testing rate of del(17p)/TP53 mutation and IGHV mutation status in clinical practice according to guideline recommendations.