Minimal residual disease is an independent predictor for 10-year survival in CLL

Minimal residual disease (MRD) negativity, defined as <1 chronic lymphocytic leukemia (CLL) cell detectable per 10 000 leukocytes, has been shown to independently predict for clinical outcome in patients receiving combination chemoimmunotherapy in the frontline setting. However, the long-term prognostic value of MRD status in other therapeutic settings remains unclear. Here, we retrospectively analyzed, with up to 18 years follow-up, all patients at our institution who achieved at least a partial response (PR) with various therapies between 1996 and 2007, and received a bone marrow MRD assessment at the end of treatment according to the international harmonized approach. MRD negativity correlated with both progression-free survival (PFS) and overall survival (OS) independent of the type and line of treatment, as well as known prognostic factors including adverse cytogenetics. The greatest impact of achieving MRD negativity was seen in patients receiving frontline treatment, with 10-year PFS of 65% vs 10% and 10-year OS of 70% vs 30% for MRD-negative vs MRD-positive patients, respectively. Our results demonstrate the long-term benefit of achieving MRD negativity, regardless of the therapeutic setting and treatment modality, and support its use as a prognostic marker for long-term PFS and as a potential therapeutic goal in CLL

Report of the European Myeloma Network on multiparametric flow cytometry in multiple myeloma and related disorders

This is an open access paper.-- et al.The European Myeloma Network (EMN) organized two flow cytometry workshops. The first aimed to identify specific indications for flow cytometry in patients with monoclonal gammopathies, and consensus technical approaches through a questionnaire-based review of current practice in participating laboratories. The second aimed to resolve outstanding technical issues and develop a consensus approach to analysis of plasma cells. The primary clinical applications identified were: differential diagnosis of neoplastic plasma cell disorders from reactive plasmacytosis; identifying risk of progression in patients with MGUS and detecting minimal residual disease. A range of technical recommendations were identified, including: 1) CD38, CD138 and CD45 should all be included in at least one tube for plasma cell identification and enumeration. The primary gate should be based on CD38 vs. CD138 expression; 2) after treatment, clonality assessment is only likely to be informative when combined with immunophenotype to detect abnormal cells. Flow cytometry is suitable for demonstrating a stringent complete remission; 3) for detection of abnormal plasma cells, a minimal panel should include CD19 and CD56. A preferred panel would also include CD20, CD117, CD28 and CD27; 4) discrepancies between the percentage of plasma cells detected by flow cytometry and morphology are primarily related to sample quality and it is, therefore, important to determine that marrow elements are present in follow-up samples, particularly normal plasma cells in MRD negative cases.The meetings were sponsored by the European Myeloma.Peer Reviewe

Results of the randomized phase IIB ADMIRE trial of FCR with or without mitoxantrone in previously untreated CLL

ADMIRE was a multi-center, randomized-controlled, open, phase IIB superiority trial in previously untreated Chronic Lymphocytic Leukemia (CLL). Conventional frontline therapy in fit patients is fludarabine, cyclophosphamide and rituximab (FCR). Initial evidence from non-randomized Phase II trials suggested that the addition of mitoxantrone to FCR (FCM-R) improved remission rates. 215 patients were recruited to assess the primary endpoint of complete remission (CR) rates according to IWCLL criteria. Secondary endpoints were progression-free survival (PFS), overall survival (OS), overall response rate, minimal residual disease (MRD) negativity and safety. At final analysis, CR rates were 69.8% FCR vs 69.3% FCM-R [adjusted odds ratio (OR): 0.97; 95%CI: (0.53-1.79), P=0.932]. MRD-negativity rates were 59.3% FCR vs 50.5% FCM-R [adjusted OR: 0.70; 95% CI: (0.39-1.26), P=0.231]. During treatment, 60.0% (n=129) of participants received G-CSF as secondary prophylaxis for neutropenia, a lower proportion on FCR compared with FCM-R (56.1 vs 63.9%). The toxicity of both regimens was acceptable. There are no significant differences between the treatment groups for PFS and OS. The trial demonstrated that the addition of mitoxantrone to FCR did not increase the depth of response. Oral FCR was well tolerated and resulted in impressive responses in terms of CR rates and MRD negativity compared to historical series with intravenous chemotherapy

Eradication of minimal residual disease improves overall and progression free survival in patients with chronic lymphocytic leukaemia, evidence from NCRN CLL207: A Phase II trial assessing alemtuzumab consolidation.

With immunochemotherapy, remission duration and survival in patients with CLL is dependent on the level of minimal residual disease after treatment. This phase II trial assessed alemtuzumab consolidation post-chemotherapy in patients who responded with persistent low levels of detectable disease. Blood was screened for MRD using multi-parameter flow cytometry, 6 to 24 months post-chemotherapy. MRD-positive participants received alemtuzumab 30mg subcutaneously 3 times weekly for 6 weeks. Following a marrow assessment, MRD-negative participants or non-responders stopped therapy and MRD-positive participants with 1+ log reduction had 6 more weeks of alemtuzumab. Alemtuzumab consolidation was received by 47 participants. One death and 19 of 22 serious adverse events reported from 17 (36%) participants were alemtuzumab related. MRD eradication from blood and bone marrow was achieved in 39 (83%) participants at the end of consolidation, with 18 (38%) remaining MRD-negative in the blood 6 months later. Of the 18 MRD-negative participants at 6 months, the median time to MRD relapse was 46 months which was similar to patients who were MRD-negative at baseline and were followed up. The 5-year PFS and OS of MRD-negative participants at 6 months was significantly better than MRD-positive participants (PFS: 78%vs39% (p=0.010), OS: 89%vs64% (p=0.029))

Results of the randomized phase IIB ARCTIC trial of low dose Rituximab in previously untreated CLL

ARCTIC was a multi-center, randomized-controlled, open, phase IIB non-inferiority trial in previously untreated Chronic Lymphocytic Leukemia (CLL). Conventional frontline therapy in fit patients is fludarabine, cyclophosphamide and rituximab (FCR). The trial hypothesized that including mitoxantrone with low-dose rituximab (FCM-miniR) would be non-inferior to FCR. 200 patients were recruited to assess the primary endpoint of complete remission (CR) rates according to IWCLL criteria. Secondary endpoints were progression-free survival (PFS), overall survival (OS), overall response rate, minimal residual disease (MRD) negativity, safety and cost-effectiveness. The trial closed following the pre-planned interim analysis. At final analysis, CR rates were 76% FCR vs 55% FCM-miniR [adjusted odds-ratio: 0.37; 95% CI: 0.19–0.73]. MRD-negativity rates were 54% FCR vs 44% FCM-miniR. More participants experienced Serious Adverse Reactions with FCM-miniR (49%) compared to FCR (41%). There are no significant differences between the treatment groups for PFS and OS. FCM-miniR is not expected to be cost-effective over a lifetime horizon. In summary, FCM-miniR is less well tolerated than FCR with an inferior response and MRD-negativity rate and increased toxicity, and will not be taken forward into a confirmatory trial. The trial demonstrated that oral FCR yields high response rates compared to historical series with intravenous chemotherapy

Association of Minimal Residual Disease With Superior Survival Outcomes in Patients With Multiple Myeloma: A Meta-analysis

Importance: Numerous studies have evaluated the prognostic value of minimal residual disease (MRD) in patients with multiple myeloma (MM). Most studies were small and varied in terms of patient population, treatment, and MRD assessment methods. Objective: To evaluate the utility of MRD detection in patients with newly diagnosed MM. Data Sources: A Medline search was conducted for articles published in English between January 1990 and January 2016. Study Selection: Eligible studies reported MRD status and progression-free survival (PFS) or overall survival (OS) in 20 or more patients following treatment. Among 405 articles identified, 21 met the initial eligibility criteria and were included in the analysis. Data Extraction and Synthesis: Information on patient characteristics, treatment, MRD assessment, and outcomes were extracted using a standard form. Main Outcomes and Measures: The impact of MRD status on PFS and OS was assessed by pooling data from relevant trials. Data were adjusted to allow for different proportions of patients with MRD in different studies, and analyzed using the Peto method. Forest plots were created based on Cox model analysis. Other prespecified research questions were addressed qualitatively. Results: Fourteen studies (n = 1273) provided data on the impact of MRD on PFS, and 12 studies (n = 1100) on OS. Results were reported specifically in patients who had achieved conventional complete response (CR) in 5 studies for PFS (n = 574) and 6 studies for OS (n = 616). An MRD-negative status was associated with significantly better PFS overall (hazard ratio [HR], 0.41; 95% CI, 0.36-0.48; P < .001) and in studies specifically looking at CR patients (HR, 0.44; 95% CI, 0.34-0.56; P < .001). Overall survival was also favorable in MRD-negative patients overall (HR, 0.57; 95% CI, 0.46-0.71; P < .001) and in CR patients (HR, 0.47; 95% CI, 0.33-0.67; P < .001). Tests of heterogeneity found no significant differences among the studies for PFS and OS. Conclusions and Relevance: Minimal residual disease-negative status after treatment for newly diagnosed MM is associated with long-term survival. These findings provide quantitative evidence to support the integration of MRD assessment as an end point in clinical trials of MM

Telomere length predicts for outcome to FCR chemotherapy in CLL

We have previously shown that dividing patients with CLL into those with telomeres inside the fusogenic range (TL-IFR) and outside the fusogenic range (TL-OFR) is powerful prognostic tool. Here, we used a high-throughput version of the assay (HT-STELA) to establish whether telomere length could predict for outcome to fludarabine, cyclophosphamide, rituximab (FCR)-based treatment using samples collected from two concurrent phase II studies, ARCTIC and ADMIRE (n = 260). In univariate analysis, patients with TL-IFR had reduced progression-free survival (PFS) (P < 0.0001; HR = 2.17) and shorter overall survival (OS) (P = 0.0002; HR = 2.44). Bifurcation of the IGHV-mutated and unmutated subsets according to telomere length revealed that patients with TL-IFR in each subset had shorter PFS (HR = 4.35 and HR = 1.48, respectively) and shorter OS (HR = 3.81 and HR = 2.18, respectively). In addition, the OS of the TL-OFR and TL-IFR subsets were not significantly altered by IGHV mutation status (P = 0.61; HR = 1.24 and P = 0.41; HR = 1.47, respectively). In multivariate modeling, telomere length was the dominant co-variable for PFS (P = 0.0002; HR = 1.85) and OS (P = 0.05; HR = 1.61). Taken together, our data suggest that HT-STELA is a powerful predictor of outcome to FCR-based treatment and could be used to inform the design of future risk-adapted clinical trials

GA101 (obinutuzumab) monocLonal Antibody as Consolidation Therapy In CLL (GALACTIC) trial: study protocol for a phase II/III randomised controlled trial

Background: Chronic lymphocytic leukaemia (CLL) is the most common adult leukaemia. Achieving minimal residual disease (MRD) negativity in CLL is an independent predictor of survival even with a variety of different treatment approaches and regardless of the line of therapy. Methods/design: GA101 (obinutuzumab) monocLonal Antibody as Consolidation Therapy In CLL (GALACTIC) is a seamless phase II/III, multi-centre, randomised, controlled, open, parallel-group trial for patients with CLL who have recently responded to chemotherapy. Participants will be randomised to receive either obinutuzumab (GA-101) consolidation or no treatment (as is standard). The phase II trial will assess safety and short-term efficacy in order to advise on continuation to a phase III trial. The primary objective for phase III is to assess the effect of consolidation therapy on progression-free survival (PFS). One hundred eighty-eight participants are planned to be recruited from forty research centres in the United Kingdom. Discussion: There is evidence that achieving MRD eradication with alemtuzumab consolidation is associated with improvements in survival and time to progression. This trial will assess whether obinutuzumab is safe in a consolidation setting and effective at eradicating MRD and improving PFS. Trial registration: ISRCTN, 64035629. Registered on 12 January 2015. EudraCT, 2014-000880-42. Registered on 12 November 2014

Early emergence of CD19-negative human antibody secreting cells at the plasmablast to plasma cell transition

Long-lived human plasma cells (PCs) play central roles in immunity and autoimmunity and are enriched amongst the subpopulation of CD19-negative human PCs. However, whether human CD19-negative PCs are necessarily ″aged″ cells that have gradually lost CD19 expression is not known. Assessing peripheral blood samples at steady state and during the acute response to influenza vaccination in healthy donors we identify the presence of phenotypic CD19-negative plasmablasts, the proliferative precursor state to mature PCs, and demonstrate by ELISpot that these are antibody-secreting cells (ASCs). During the acute response to influenza vaccination CD19-positive, CD19-low and CD19-negative ASCs secrete vaccine-specific antibody and show linked IGHV repertoires. To address precursor/product relationships we employ in vitro models which mimic both T-dependent and T-independent differentiation finding that the CD19-negative state can be established at the plasmablast to PC transition, that CD19-negative PCs increase as a percentage of surviving PCs in vitro, and that CD19-negative and CD19-positive PCs can be maintained independently. These data provide proof-of-principle for the view that newly generated ASCs can acquire a mature PC phenotype accompanied by loss of CD19 expression at an early stage of differentiation and that ″aging″ is not an obligate requirement for a CD19-negative state to be established