Another attempt to get FCA up front

This is not quite the right trial, but it is an attempt by the Dutch group to introduce alemtuzumab up front in high risk patients. The other arm should have been FCR not FC and they were wrong to include trisomy 12 in the high risk group.

290 Immunochemotherapy with Low-Dose Subcutaneous Alemtuzumab (A) Plus Oral Fludarabine and Cyclophosphamide (FC) Is Safe and Induces More and Deeper Complete Remissions in Untreated Patients with High-Risk Chronic Lymphocytic Leukemia (CLL) Than Chemotherapy with FC Alone. An Early Analysis of the Randomized Phase-III HOVON68 CLL Trial

In CLL unmutated immunoglobulin heavy chain (IGH) genes, deletions of chromosome 17p or 11q and trisomy 12 are associated with an unfavorable outcome. At the outset of the present trial, phase II studies had shown promising results of immunochemotherapy with FC + rituximab, but the optimal immunochemotherapy regimen was not known, especially not for high-risk CLL patients. The aim of this trial was to improve the outcome of high-risk CLL by the addition of the monoclonal antibody alemtuzumab to the currently best known chemotherapy FC. Because of the recognized immunosuppressant activity of both treatment modalities, a low-dose alemtuzumab approach was chosen and vigilance and prophylaxis towards infection upheld throughout the study.

Previously untreated, fit patients up to 75 years of age with high-risk CLL in need of treatment according to the NCI/IWCLL guidelines were randomized to either oral FC (F 40 mg/m2 D1-3 and C 250 mg/m2 D1-3) or AFC: oral FC + subcutaneous (sc.) alemtuzumab 30 mg, in cycle 1 day -1 to +1, in cycles 2-6 30 mg day 1 only. Responses and endpoints were defined according to NCI/IWCLL guidelines. The primary endpoint was progression-free survival (PFS) on intent-to-treat with progression defined as no response after three cycles of induction treatment, progression of disease, relapse or death whichever occurred first. Secondary endpoints included the rate of complete remission (CR) and the rate of MRD – negative CR (by PCR or flow cytometry), overall survival (OS) and toxicity. We assumed that the addition of alemtuzumab to FC could increase the CR rate from the estimated 20% to 40% and the median PFS from 30 to 42 months.

The study population of 281 patients was included 2006-2010. As of July 2011 262 patients (93%) were evaluable, 129 in the AFC arm and 133 in the FC arm with a median follow-up of 30 months (range 2-63 months). The median age was 60 years (range 27-75) and 75% were males. Twelve % had Binet stage A, 54% stage B and 34% stage C. Beta-2-microglobulin was increased in the majority of the patients (median 3.7 g/ml). Eighty-nine % had unmutated IGH genes and FISH revealed 27% with del 11q, 18% with trisomy 12 and 11% with del 17p according to the hierarchical model. All risk parameters were well balanced between the two arms. Sixty-three% completed all six cycles in each arm, 73% completed at least 5 cýcles AFC while 66% completed 5 cycles FC.

The overall response to AFC and FC was 88% and 80% respectively (NS), the CR rates were 57% and 45% respectively (P=0.049), and the rates of MRD-negative CR were 29% and 17% respectively (P=0.02). The median PFS following AFC and FC was 37 and 31 months respectively (P=0.08). The median OS has not been reached. In the subgroups with 17p deletions, 11q deletions, trisomy 12 or unmutated IGH genes a trend of improved PFS following AFC was seen, but this did not reach significance due to small numbers. There were no differences in response or PFS between treatment arms according to Binet stage or beta-2-microglobulin level.

Severe adverse events, mostly grade 3, were significantly more frequent following AFC than FC: 145 vs 90 (P=0.0001), including flu-like syndrome due to the antibody (27 vs. 2), opportunistic infections (25 vs 11), and organ affection (34 vs 14). The numbers of neutropenic and other infections did not differ. Six treatment related deaths were reported in each arm to a total treatment related mortality of 4%.

In this selected high-risk CLL population, the addition of low-dose sc. alemtuzumab to FC induced a higher rate and higher quality of complete remission than FC alone, which, however, in this early analysis, did not yet translate into significantly prolonged PFS or OS. As expected, the combination is more immuno-suppressant than chemotherapy alone, leading to a higher number of opportunistic infections. With proper vigilance and prophylactic measures, these infections were manageable and did not lead to any excess mortality.

Second-line treatment after CLL8

What do the early relapsers from CLL8 actually get as second line treatment and does it work? The information in this German ASH abstract tells us and the results are rather surprising.

2863 Second-Line Therapies After Treatment with Fludarabine, Cyclophosphamide, and Rituximab (FCR) or Fludarabine and Cyclophosphamid Alone (FC) for Chronic Lymphocytic Leukemia (CLL) within the CLL8-Protocol of the German CLL Study Group (GCLLSG)

The CLL8-trial is the first study that has shown not only an increase in complete remission rates and progression-free survival, but also an improved overall survival (OS) in physically fit, treatment-naúve CLL-patients (pts) with FCR-chemoimmunotherapy in comparison to FC alone. Despite this remarkable progress, CLL remains an incurable disease and virtually all pts will eventually relapse. So far, little is known about the efficacy of 2nd-line therapies of these pts.

The combination CHOP-R was the most common treatment (35 pts, 15% of all 2nd-line therapies), applied mainly in cases with a relapse ≤24 months after FC/FCR, whereas FCR or BR were administered predominantly in case of relapse less than 24months (32 and 27 pts, 14% and 12%). Other prevalent 2nd-line therapies were single agent Alemtuzumab(A) (20 pts) or Bendamustine (17 pts), CHOP and FC (11 pts respectively), chlorambucil (9 pts) as well as R monotherapy (7 pts). 9 pts underwent stem cell transplantations. Second-line therapies with FC+/-R and B+/-R were found to be more effective with regard to treatment-free survival (TFS, time to 2nd relapse) and OS when compared to A or CHOP-R and CHOP-like chemotherapies. However, the outcome of 2nd-line therapies seemed to be influenced by the 1st-line treatment. In pts initially treated with FC, FCR was found to be the most effective 2nd-line therapy (TFS: 23 months, OS: not reached), whereas in pts initially treated with FCR, a substitution of the chemotherapeutic agents FC by B seemed justified, as TFS was superior after 2nd-line treatment with B+/-R (16 and 18 months respectively) when compared to FC+/-R (11 and 8 months). Furthermore, in pts who had received FCR for 1st-line treatment, chemotherapy with FC or B was found to be at least equally or even more effective in prolonging OS than FCR or BR (OS calculated from beginning of 2nd-line therapy: FC: not reached, B: 45, FCR: 19, and BR 18 months).

Second-line treatments of pts with a relapse after FC or FCR were found to be surprisingly heterogeneous even though the patient collective examined is comparatively homogenous due to the inclusion/exclusion criteria of a clinical trial. As the majority of CLL8-patients is still in remission and has not yet received a 2nd-line treatment, the therapies captured in this analysis are predominantly 2nd-line therapies for earlier relapses. Therefore and because of the short follow-up time, the results ought to be considered as preliminary and descriptive trends. The worse outcome of CHOP-like regimen and A-based therapies in comparison to more established CLL-therapies such as FC+/-R and B+/-R might be related to the fact, that these therapies were administered more often in case of an early relapse after FC/FCR, which is known to be related to other poor prognostic factors. Nevertheless, the observation of favorable TFS and OS times after 2nd-line treatment with FC+/-R and B+/-R supports the recommendation to repeat chemoimmunotherapy in case of a relapse >24 months after 1st-line treatment. Further analyses are needed to confirm the observation that chemotherapy (FC or B) without rituximab might be sufficient for for 2nd-line treatment after FCR.

A role for ras genes in chlorambucil resistance?

From this Italian ASH abstract it seems that Chlorambucil-rituximab is a promising regimen in CLL patients over-65. Those who respond have molecular differences to those who don't. ras genes seem to be important.

294 Rituximab Plus Chlorambucil As Initial Treatment for Elderly Patients with Chronic Lymphocytic Leukemia (CLL): Effect of Pre-Treatment Biological Characteristics and Gene Expression Patterns on Response to Treatment Robin Foa, Stefania Ciolli, Francesco Di Raimondo, Giovanni Del Poeta, Francesco Lauria, Francesco Forconi, Antonio Cuneo, Agostino Cortelezzi, Francesco Nobile, Vincenzo Callea, Maura Brugiatelli, Massimo Massaia, Stefano Molica, Livio Trentin, Rita Rizzi, Giorgina Specchia, Lorella Orsucci, Achille Ambrosetti, Marco Montillo, Pier Luigi Zinzani, Felicetto Ferrara, Fortunato Morabito, Maria Angela Mura, Silvia Soriani, Marilisa Marinelli, Maria Stefania De Propris, Alessandra Alietti, Eva J. Runggaldier, Enrica Gamba, Ilaria Del Giudice, Silvia Bonina1, Francesca Romana Mauro, Sabina Chiaretti and Anna Guarini.

Rituximab plus fludarabine/cyclophosphamide (R-FC) is currently the standard of care for fit patients with untreated or relapsed CLL. However, patients with CLL are predominantly an elderly population and many of these patients may have comorbidities that make them less suitable to receive fludarabine-containing therapy. Chlorambucil-based treatments are frequently used for these patients despite the fact that clinical benefits are limited. There is a need for well-tolerated and more efficacious treatment regimens for these patients.

The ML21445 study evaluated the combination of rituximab and chlorambucil (R-chlorambucil) as first-line treatment for patients with CLL considered ineligible for treatment with the current standard of care, R-FC. Patients aged >65 years (or 60–65 years and ineligible for fludarabine) were treated with eight 28-day cycles of chlorambucil (8 mg/m2/day Days 1–7) with rituximab administered on Day 1 of cycle 3 (375 mg/m2) and cycles 4–8 (500 mg/m2). Patients with a response at the end of induction were randomized to rituximab maintenance therapy (375 mg/m2 every 8 weeks for 2 years) or observation. The induction phase of the study is complete while the maintenance phase is still ongoing.

This is a rather low dose for chlorambucil. 10mg/m2/day for 10 days would be equivalent to what patients got in LRF CLL4

The overall response rate (ORR) in 85 patients who received at least one dose of rituximab during induction was 81.2% (n = 69) with 16.5% (n = 14) achieving a complete response (CR) and 2.4% (n = 2) a CR with incomplete bone marrow recovery (CRi). ORR and CR rates were similar across the different Binet stages (ORR: Binet A 86.4%, Binet B 79.6%, Binet C 78.6%) and age categories (ORR: 60–64 years 84.6%, 65–69 years 85.2%, 70–74 years 75.0%, ≥75 years 81.0%). Two of four patients aged ≥80 years responded to induction treatment.

ORR of 81% is excellent for a chlorambucil containing regimen.

Logistic regression analysis revealed no correlation between known biological prognostic factors – CD38, cytogenetics, IGHV mutational status, ZAP-70, thymidine kinase, soluble CD23, and beta-2 microglobulin – and response to treatment. To further investigate possible factors influencing response, pre-treatment patterns of gene expression were analyzed in different patient subgroups. Material was available for 62 patients, including 16 with CR/CRi, 41 partial responders and 5 non-responders. In an exploratory analysis, mRNA expression was examined using Affymetrix® Human Genome U133 microarrays. This revealed marked differences in pre-treatment gene expression profiles between response groups. Non-responders showed a homogeneous gene expression signature involving up-modulation of transcripts involved in anti-apoptotic and pro-proliferative pathways, including K-ras and N-ras. CR/CRi patients also showed a homogeneous pattern of gene expression that was clearly distinct from non-responding patients, while patients with a partial response showed a more heterogeneous pattern of gene expression before treatment.

Apart from TP-53 effects response rates usually do not vary with rituximab containing regimens, but PFS does.

These initial findings reflect the heterogeneity of CLL and suggest that microarray analysis of gene expression may be useful in predicting response to R-chlorambucil in elderly patients with CLL.

CLL8 the same bad news is bad news.

977 Prediction of Poor Outcome in CLL Patients Treated with FCR (Fludarabine, Cyclophosphamide, Rituximab) in the CLL8 Trial of the German CLL Study Group (GCLLSG) Anna Fink, Raymonde Busch, Natali Pflug, Sebastian Boettcher, Dirk Winkler, Andreas Buehler, Matthias Ritgen, Kirsten Fischer, Barbara Eichhorst, Clemens-Martin Wendtner, Myriam Mendila, Michael K. Wenger, Hartmut Doehner, Michael Kneba, Stephan Stilgenbauer and Michael Hallek.

Introduction:

For physically fit patients (pts) with chronic lymphocytic leukemia (CLL) the first-line treatment with fludarabine, cyclophosphamide and rituximab (FCR) is the new standard therapy. However, subgroup analyses in the CLL8 trial revealed that patients with a median progression free survival (PFS) of < 24 months after randomization showed a significantly shorter overall survival (OS) compared with pts achieving a PFS of ³ 24 months. 15 % of these patients were characterized by both, the presence of 17p deletions and TP53 gene mutations, another 7.5% by TP53 mutation alone. Interestingly, the majority of patients with a poor prognosis could not be defined by a mutation of p53 or del(17p). Therefore, an effort was made to further characterize the subgroup of patients with poor prognosis.

Methods:

In 143 patients out of 408 patients who received FCR in the CLL8 trial of the GCLLSG, an assessment of minimal residual disease (MRD) was available at final restaging. These patients were used for this analysis. Results for the primary endpoint PFS, the secondary endpoint OS, and central diagnostics performed for genomic aberrations by FISH and the IGHV gene status as well as for serum parameters before the start of therapy were available for all pts. MRD was determined at final restaging by multi-color flow cytometry from peripheral blood with a sensitivity of at least 10-4. The Kaplan-Meier method and the log-rank test were used to compare PFS and OS in pts with various combinations of risk factors.

Results:

This patient cohort used for the analysis was representative of the entire FCR population (n=408). There were no significant differences compared with the entire FCR population for age, ECOG status, B-symptoms, Binet or Rai stages, deletion of chromosome 17p, 11q, or 13q, trisomy 12, serum levels for s-TK or s-ß2m. A combination of MRD levels of less than 10e2 or of MRD levels of less than 10e4 to less than 10e2 plus at least one of the following three parameters (del(17p) or TP53 mutation or an unmutated IGHV-status) defined a group of patients at high risk of early progression (HR). The median PFS of HR pts was 22 months, the median PFS for patients defined as low risk (LR; n=103) was 69 months. HR patients had a 6.4 fold increased risk for progression (HR 6.4 95% CI: 3.970-10.347; p=0.0001) and a 5.7 fold increased risk for death, with a median OS of only 57 months (assessed from the beginning of FCR therapy). In contrast, median OS was not reached in the LR group at the time point of the analyses (HR 5.758, 95%CI:2.799-11.844, p=0.0001)

Conclusion:

The combined use of genetic markers and an MRD assessment at final restaging allows to identify CLL patients with a very poor outcome after FCR therapy. The high risk group identified by this approach should be treated within clinical trials using novel strategies including maintenance protocols or allogeneic stem cell transplantation.

A predictable picture is emerging. The same old prognostic factors - IGVH mutations and TP53 abnormalities determine the pace of the disease. It confirms my opinion that all CLL patients ought to get them done.

ASCT buys a later second treatment for 4 months of impaired quality of life.

There is still some lingering thought that autologous stem cell transplant is an advantageous way of treating some cases of CLL, despite papers suggesting that the risk of secondary MDS/AML is higher than with conventional therapy. This abstract from ASH this year seems to gainsay that.

1989 High-Dose Therapy and Autologous Hematopoietic Stem Cell Transplantation (ASCT) Has a Significant but Transient Impact on Quality of Life: Lessons From the Chronic Lymphocytic Leukemia (CLL) ASCT Study by the CLL Subcommittee of the Chronic Leukemia Working Party of the European Group for Blood and Marrow Transplantation Liesbeth C. de Wreede, Maggie Watson, Donald Milligan, Mauricette Michallet, Peter Dreger, Marleen van Os, Claire E. Dearden, Catherine Cordonnier, Michel Leporrier, Vladimir Koza, Janis Homewood, Bernadette Corront, Gabriela M. Baerlocher, Wolfgang Herr, Dietger Niederwieser, Laurent Sutton, Theo M. de Witte, and Johannes Schetelig,

Objective:

High-dose therapy (HDT) and ASCT is the standard of care in a variety of hematologic malignancies. Whereas for some indications a survival advantage for HDT and ASCT has been demonstrated, a benefit only in terms of better progression-free survival has been shown for CLL. Because of this the quality of life (QoL) deserves particular attention. QoL assessment was a major focus of a randomized controlled EBMT-Intergroup trial on the value of HDT compared to observation in first or second remission of CLL.

Methods:

222 patients were enrolled into the study and allocated to either ASCT or observation. In the transplant arm, 72% received HDT and ASCT (for those median time from randomization to transplant was 3.01 months); in the observation arm 9% received ASCT. QoL was assessed with the EORTC QLQ C30 version 3.0, a questionnaire that has to be filled in by the patients. The answers to the questions yielded 15 scores, each on a scale from 0 to 100. The scores represent 15 domains: global health status/QoL, 5 functional scales (100 representing perfect health) and 9 symptom scales (0 representing no complaints). QoL forms had to be completed at randomization and at months 4, 8, 12, and 24. Data on 56%, 53%, 54%, 61%, and 50% of the baseline patients are available for the respective periods. Missing forms were not systematically related to baseline variables or relapse. The numbers of drop outs due to death at 2 years were 5 patients in the HDT arm and 4 patients in the control arm.

All QoL outcomes were analyzed with mixed models according to the intent to treat principle. Time (as factor), age, gender, treatment arm and the interaction of time and treatment arm were modelled as fixed effects, whereas individual random effects were added for the intercept.

Results:

Global health status/QoL at 4 months (estimated effect from the multivariate model -7.15, p=0.034) was significantly inferior in the transplant cohort compared to the control group. At 8 months the estimated effect of HDT on global health status/QoL was -3.06 (p=0.36). This difference further diminished over the first year (estimate at 1 year -0.53, p=0.87). QoL did not decrease independently from the treatment during the first 2 years. The same global pattern of change over time was observed for physical functioning, role functioning and social functioning; however, the treatment impact was still significant at 8 months for physical functioning (-6.58; p=0.025) and social functioning (-11.18; p=0.014). No significant covariate effects could be delineated for either of these scales apart from age having a beneficial effect on social functioning.

Conclusions:

Quality of life is affected multi-dimensionally in the first year after high-dose therapy and autologous stem cell support. The negative impact of HDT on QoL has disappeared after two years. Patients should be informed that HDT followed by ASCT impairs quality of life in the first year after transplantation.

The plain facts are that you cannot get improved survival from ASCT, but you do delay your next treatment at the cost of a worse quality of life for 4 months.

How exactly do American doctors treat CLL?

Back to the ASH abstracts. This is one that tries to work out what is actually hapenning in America with the treament of CLL.

2864 Patterns of Care for Patients with Chronic Lymphocytic Leukemia (CLL): The Connect® CLL Disease Registry Jeff Sharman, Christopher R Flowers, Mark Weiss, David Grinblatt, Charles Farber, Neil Kay, Thomas Kipps, Nicole Lamanna, Chris Pashos, Ian W Flinn, Mark Kozloff, Susan Lerner, Arlene Swern, Kristen A Sullivan, Thomas K. Street, and Michael Keating.

Introduction:

Clinical trials have illuminated a number of unique treatment strategies for patients with CLL. The impact of these strategies on routine practice remains unknown as trial participants may not reflect the same population encountered outside of a clinical trial setting. Many questions remain regarding the sequencing of therapies based on age and performance status. By characterizing current patterns of care; patients, treating physicians, and regulatory agencies will be able to understand the current landscape of CLL treatment. The Connect® CLL registry was designed to report the natural history and real world management of patients receiving therapy for CLL. In this first report, we characterize the therapeutic approaches used for the treatment of patients with CLL of different age groups (i.e. < 65 years, 65–75 years, and ≥ 75 years) and with an ECOG PS status score of 0 compared to 1 or greater.

Methods:

Connect® CLL is a prospective, longitudinal, observational, multi-center registry conducted in community and academic research centers in the United States. At present, 237 sites are actively participating with a projected study enrollment of 1500 patients. Eligible patients are to be enrolled within 2 months of being initiated on any line of therapy; whether initial therapy or salvage therapy. Each patient will be followed for up to 60 months. Clinical data, physician choices, patient-reported health-related quality of life, response and survival are to be collected approximately every 3 months during participation.

Results:

A total of 607 patients have been enrolled (4% from academic sites) with a median age of 70 years. 198 were < 65 years old (age group 1), 187 were between 65–75 years old (age group 2), and 222 were ≥ 75 years old (age group 3). ECOG status varied across the three age groups, with an ECOG status score of ≥ 1 for 39%, 52%, and 70% of patients respectively. Treatment patterns varied across the age groups and by ECOG status in the 496 patients reporting therapies. The most commonly recorded first-line regimens independent of age included fludarabine (F) cyclophosphamide (C) and rituximab (R) (33%), bendamustine (B) +/- R (19%), F +/- R (15%), or investigational therapy (15%). For second-line regimens and beyond, the most frequently recorded regimen was B +/- R (30%), FCR (23%), other F-based regimens (13%), or investigational therapy (8%).

Note that nearly three quarters of patients over-75 had a poor ECOG score. This is why you can't translate clinical trials results to how to treat most cases of CLL. The average age of diagnosis in CLL is at least 70 and the age thay theu need treatment for the first time is even older.


The use of FCR for first-line treatment decreased significantly with increasing age group, (45%, 32%, 20%, for age group 1, 2, 3 respectively, p=0.04, spearman correlation) while use of F +/- R remained level across the age groups (14%, 15%, 15%, respectively). Compared to age group 1, first-line therapy with B +/- R in age groups 2 and 3 (15%, 22%, 21%, respectively) was higher but did not achieve statistical significance. B +/- R represented the most common treatment for all age groups (37%, 26%, 29%, respectively) as second line therapy but did not vary by age (P=0.35). The use of chlorambucil was infrequent in all age groups, but was more common in age group 3 patients compared to the others (P=0.01), in both first-line (2%, 4%, 12%, respectively) and subsequent lines of therapy (0%, 1%, 8%, respectively).

Note: only 35% of the over-75s even had fludarabine, let alone FCR. Mind you this would have included many mutated patients who would never need any treatment.

Treatment assignments did not vary by ECOG PS score for patients in age group 1. First-line therapy for patients with an ECOG PS score of 0 in age groups 2 and 3 consisted of FCR (32% and 15%, respectively), F +/- R (19% and 15%, respectively), B +/- R (16% and 15%, respectively), and alkylating agents (3% and 23%, respectively). Patients in age groups 2 and 3 with ECOG PS score ≥ 1 received B +/- R regimen (33% and 22%, respectively), FCR (23% and 21%, respectively), F +/- R (14% and 10%, respectively) and alkylating agents (7% and 9%, respectively) as first-line therapy. Further description and clarification on the various treatment regimens based on the three age groups and by ECOG PS score will be presented at the meeting.

Note: B +/- R does not have any validation by clinical trials in this situation. It is toxic, but I am willing to believe that there is another mechanism by which it has an advantage second line.

Conclusion:

The Connect® CLL Registry is the largest prospective, multicenter registry in the United States evaluating management for patients with CLL. With the currently available data, we characterize the extent to which age and performance status are associated with treatment selection in both first-line and subsequent lines of therapy in routine practice. As enrollment increases and additional follow-up is completed, the data will provide more extensive and real world overview of the current treatment strategies used in CLL patients.

This study is obviously funded by Celgene. I wonder what their ulterior motive is in doing so.

The kinetics of MRD

The German CLL8 trial has been the most important study in CLL thus far reported. But there are a lot of scientific data that derive from this trial that are yetto be reported. The value of minimal residual disease measurements is an important investigation that will be reported at ASH. Here is the German abstract:

1777 Minimal Residual Disease (MRD) Re-Growth Kinetics Are An Independent Predictor for Progression Free Survival (PFS) in Chronic Lymphocytic Leukemia (CLL) and Are Related to Biologically Defined CLL-Subgroups – Results From the CLL8 Trial of the German CLL Study Group (GCLLSG) Sebastian Boettcher, Matthias Ritgen, Kirsten Fischer,, Stephan Stilgenbauer, Raymonde Busch, Gunter R. Fingerle-Rowson, Anna-Maria Fink, Andreas Buehler, Dirk Winkler, Michael K. Wenger, Myriam Mendila, Clemens Wendtner, Barbara Eichhorst, Hartmut Döhner, Michael Hallek, and Michael Kneba.

MRD single time point assessments during therapy and at the end of treatment have been identified as independent predictors of PFS and overall survival in CLL patients (pts) by our group and others. However, it is currently unknown whether MRD kinetics during follow-up (FU) also have prognostic significance and whether kinetics show associations with CLL risk features. We therefore investigated MRD during treatment-free FU within the CLL8 trial of the GCLLSG.

MRD kinetics were analyzed in 256 pts who had not progressed 1 year after completion of therapy and for whom at least 2 peripheral blood MRD assessments during the subsequent year were available. The slope of the common logarithm of MRD / time was calculated for 193 patients with at least 2 positive MRD measurements. Median MRD increase was 6.3fold during the observation period for the whole group (i.e. 0.80 log MRD unit increase / year). We compared groups of pts who (1) were always MRD negative (25% of all 256 pts), (2) had measurable disease with a slope below median (slow re-growth, 37% of pts), and (3) had measurable disease with a slope above median (fast re-growth, 39 %).


The medians of the first measurable MRD levels during observation did not differ significantly between groups 2 (4.3 x 10-3) and 3 (1.7 x 10-3, p=.16). Pts with faster MRD re-growth kinetics (group 3) experienced a shorter median PFS (40 months) than pts with slower re-growth (group 2, 66 months), whereas median PFS has not been reached in pts who were always MRD negative (group 1, log-rank p= 3 x 10-14). Compared to group 1, group 2 and 3 pts carried increasingly higher risks of progression (HR 3.1 and 7.7, resp.). Pts showing a slow re-growth pattern (group 2) had a 2.5fold lower risk of clinical progression than pts with a greater MRD slope (group 3, p=5 x 10-6).

The prognostic significance of MRD kinetics for PFS was also tested in Cox regression analysis together with clinical response, deletion 17p, IGHV mutational status, number of treatment cycles, treatment arm, thymidine kinase, beta2-microglobulin, pre-therapeutic WBC and MRD levels 1 year after completion of therapy. MRD kinetics (p=4x10-9), MRD levels (7x10-14), cycle number (8x10-5) and IGHV mutational status (1x10-3) remained independently significant for PFS in this multivariate analysis.

We next correlated MRD slopes during the second year of FU and prognostic features in 204 pts (groups 2 and 3 plus 11 pts with early clinical relapse but measurable MRD slope during second FU year). Pts who required treatment within 2 years from diagnosis experienced a faster re-growth after therapy (.92/a) than pts with a longer treatment-free interval (.68, p=.04). The slope was significantly lower in pts with Binet A disease prior to therapy (.43/a) than in Binet B (.77/a, p =.03) and Binet C (.88/a, p=.02) pts. Pts carrying a chromosomal deletion (del) 13q as single abnormality had a significantly slower MRD re-growth pattern (.58/a) than those with del(11q) (1.0/a, p=.0004) or without cytogenetic abnormalities (1.1/a, p=.001), while the difference to pts with 12q+ (.71/a) was not significant. Pts with a mutated IGHV gene progressed slower (.54/a) than those with unmutated IGHV (.96/a, p=.0002). A thymidine kinase of at least 10 U/L was associated with a steeper MRD slope (.82/a) than lower levels (.61/a, p=.03). MRD slopes were not significantly associated with gender, WBC prior to therapy, beta2-microglobuline levels, presence of B-symptoms, or treatment arm.

We demonstrate for the first time the independent prognostic significance of MRD kinetics during FU in CLL. MRD kinetics improve the prediction of PFS even when single time point MRD assessments during FU and other major risk features in CLL are additionally considered. MRD kinetics classify known CLL risk factors into two groups. IGHV, cytogenetics, thymidine kinase, stage, and time to treatment distinguish CLL subgroups with different re-growth kinetics, likely characterizing the relationship of proliferation to spontaneous apoptosis of the CLL clone itself. Other risk features did not show an association with kinetics in spite of proven significance in the CLL8 trial. Those features likely identify differences in responsiveness to therapy. We hypothesize that maintenance strategies will chance the course of the disease most effectively in patients who are responsive to therapy but relapse early due to fast CLL re-growth.

What this paper is saying is that the prognostic factors already identified determine how rapidly MRD relapses. MRD negativity is not a cure; it just lowers the bulk of disease to a greater amount and from here the disease starts reaccumulating at the same rate as it had been before. There is no 'immune reaction' that wipes out tiny bits of CLL.

Maintenance R after FMCR

Another topic that has been insufficiently addressed is the whole question of maintenance rituximab. This Spanish abstract deals with the question after the use of FMCR which is a particularly intensive, but effective induction regime.

293 Rituximab Maintenance In Patients with Chronic Lymphocytic Leukemia (CLL) After Upfront Treatment with Rituximab Plus Fludarabine, Cyclophosphamide, and Mitoxantrone (R-FCM): Final Results of a Multicenter Phase II Trial On Behalf of the Spanish CLL Study Group (GELLC)Francesc Bosch, Pau Abrisqueta, Neus Villamor, María José Terol, Eva González-Barca, Marcos González, Christelle Ferrà, Eugenia Abella, Julio Delgado, Jose A. Garcia-Marco, Yolanda Gonzalez11, Felix Carbonell, Secundino Ferrer1, Encarna Monzo, Isidro Jarque, Ana Muntanola, Mireia Constants, Lourdes Escoda and Emili Montserrat.

The effectiveness of rituximab, fludarabine, cyclophosphamide, and mitoxantrone (R-FCM) followed by rituximab maintenance in the treatment of CLL has been investigated in a phase II clinical trial that includes two treatment parts. First, patients were given induction therapy with R-FCM up to 6 cycles, achieving an overall response (OR) rate of 93% and a CR rate of 82% (46% MRD-negative CR).

Note: this is the maintenance part of their study. The induction part of the study was published in 2009 in JCO (JCO gets the clinical parts; Blood the scientific parts of studies, but JCO tends to have a bigger Impact Factor)

Patients achieving CR or PR with the initial part of the treatment received rituximab maintenance. Here we present the final results of the treatment maintenance part, initiated three months after concluding R-FCM, and consisting of rituximab 375 mg/m2 every three months for two years (up to 8 cycles). Sixty-four patients (median age 60 years, 70% male) receiving > 4 cycles of maintenance therapy were evaluated for response, including bone marrow (BM) examination and MRD assessment by four-color flow cytometry of peripheral blood and BM. Patients in whom rituximab maintenance was prematurely interrupted (≤ 4 cycles) due to toxicity were considered as failures.

Note: the lymphoma dose of rituximab rather than the CLL dose was used.

Median number of cycles of maintenance administered was 8 (range, 1 to 8) and 76% of patients completed the entire planned treatment. Treatment was delayed due to insufficient hematological recovery in 9 cycles (2%) and to non-hematological toxicity in 4 cycles (0.8%). Neutropenia was observed in 31.3% of cycles (grade 3&4 in 8.5%), thrombocytopenia in 4.6%, and anemia in 1.2%.

Note: presumably because of toxicity, it was not possible to administer the planned dose of maintenance treatment.

At the end of the maintenance therapy, 45% of patients had low IgA serum levels, 37% low IgG, and 66% low IgM. Sixteen patients experienced grade 3&4 infectious episodes, including 9 pneumonia, 2 febrile neutropenia, 1 appendicitis, 1 myositis, 1 herpes zoster, and 1 cerebral abscess. Two patients died, one due to multifocal leukoencephalopathy and the other due to hemophagocytic syndrome. Infectious episodes grade 3&4 were observed in 19.5% of cycles with neutropenia 3&4, but in only 3% of cycles with neutropenia inferior to grade 3 (p=0.001). In contrast, no relationship was observed between infectious events and the presence of low levels of immunoglobulins or diminished CD4+ T lymphocyte counts.

Note: an extra toxicity from maintenance rituximab will be hypogammaglobulinaemia but in this case they weren't able statistically to link infectious complications to the rituximab. However, I sould be very worried about about the cerebral abscess and the two patients who died, one due to multifocal leukoencephalopathy and the other due to hemophagocytic syndrome. These are not usual post-chemotherapy complications.

After rituximab maintenance, 40.6% of patients were in MRD-negative CR, 40.6% in CR, 7.9% in PR, and 10.9% failed to treatment. Failures were due to disease progression (two patients), severe neutropenia (three patients), infectious toxicity (one patient) and death (one patient). Among 35 patients in MRD-negative CR after R-FCM induction, 22 maintained the MRD-negative status at the end of maintenance treatment, 9 (25.7%) switched from MRD-negative to MRD-positive, and 4 failed to treatment. Median time to conversion from negative to positive MRD was 45.4 months, significantly longer than that observed in patients treated with FCM only (45.4 vs. 16.4 months; p=0.011) (Bosch et al. Clin Can Res 14:155-161,2008). Moreover, among 21 patients that achieved MRD-positive CR with the initial R-FCM treatment, 2 (9.5%) became MRD-negative upon rituximab maintenance, 17(81%) continued in MRD-positive CR, 2 achieved PR, and 2 failed to maintenance therapy. Among the 8 patients in PR, 4 patients achieved CR (2 MRD-negative and 2 MRD-positive), 3 patients continued in PR, and one patient progressed. Three-year progression-free survival was 94% (95% CI 88-100%). Compared to the FCM series, maintenance with rituximab significantly prolonged the time to next treatment in patients that after the initial treatment with R-FCM were in MRD-positive CR (44.1 vs. 54.5 months, p=0.049) or PR (6.5 vs. 54.4 months, p=0.001).

Note: so it is not the whole answer. We await overall survival rates in a randomized phase 3.

In conclusion, treatment maintenance with rituximab after R-FCM in patients with CLL is feasible and might improve patients' outcome, particularly those who do not attain a MRD-negative CR after the initial, upfront therapy. However, its toxicity is not negligible. Further, ongoing studies should help to clarify the role of maintenance therapy with rituximab in the management of patients with CLL.

CHOP-R in refractory patients

Chris was kind enough to publish a link to the ASH abstracts for this year and I have just started looking at them. The first one from the German group tickles all the boxes that I have been concerned about:

2860 Cyclophosphamide, Adriamycin, Vincristine and Prednisone Plus Rituximab (CHOP-R) in Fludarabine (F) Refractory Chronic Lymphocytic Leukemia (CLL) or CLL with Autoimmune Cytopenia (AIC) or Richter’s Transformation (RT): Final Analysis of a Phase II Study of the German CLL Study Group Petra Jenke1, Barbara Eichhorst, Raymonde Busch, Nadine Anheier, Ulrich Duehrsen, Jan Duerig, Martin H. Dreyling, Manuela Bergmann, Maria Elisabeth Goebeler, Hans Juergen Hurtz, Martina Beate Stauch, Stephan Stilgenbauer, Hartmut Doehner, Prof. Dr. med., Anna-Maria Fink, Kirsten Fischer, Clemens-Martin Wendtner, and Michael Hallek,

Introduction: In the last decade, important progress has been achieved in the treatment of CLL through the use of purine analog-based chemoimmunotherapies. Several conditions remain a challenge, often with a poor outcome. Amongst these therapeutic problems are Richter’s transformation (RT), refractoriness to F-based therapies (Fref), and the occurrence of AIC, which are sometimes induced by F. Fref and RT pts have a very poor prognosis with an estimated overall survival (OS) of only 10 and 8 months (mos), respectively. Therefore, therapeutic alternatives are urgently warranted. CHOP-R has improved the outcome of pts with aggressive non-Hodgkin’s lymphoma. To test the efficacy and tolerability of the CHOP-R regimen in CLL patients with RT, Fref, or AIC, the GCLLSG initiated a prospective phase II trial.

With the usual German efficiency, rather than rely on anecdotes this is a formal phase 2 (reasonably sized) clinical trial. Of course being a phase 2 it is primarily looking at response rate, but since we have ample historical controls over what usually happens in this group of patients, we probably won't need a phase 3 to determine outcome unless this trial should prove to be a stupendous outlier.

Material and Methods: 62 patients were included in the study. Due to protocol violations, 2 patients were excluded. Within the group of Fref pts, the medical review detected 11 patients who had received pre-treatment with F (Fpret), but were not refractory according to the updated 2008 guidelines. Thus, 26 pts were classified as Fref/pret, 19 pts as AIC and 15 pts as RT. All patients received CHOP every 3 weeks (cyclophosphamide 750mg/m², adriamycin 50mg/m² and vincristine 1,4mg/m² d1; prednisone 100mg/m² d1-5). Rituximab was added starting with the 2nd cycle (375mg/m² on each d0, and 21 days after the last CHOP-R). RT pts received up to 8, Fref/pret and AIC up to 6 courses of CHOP-R. In case of PD after 3 cycles, pts went off-study. The primary endpoints were remission rate, quality and duration of response.

Note: this was the lymphoma dose of R, not the CLL dose.

Results: 79%, 73%, and 40% of AIC, Fref/pret, and RT pts were male, respectively. The median age was 65 years (y) for Fref/pret-pts, 66y in the AIC and 69y in the RT group. Binet stages for Fref/pret pts were: A: 8%; B: 27% C: 65 %. All but 3 AIC pts were at Binet stage C. Initial RT stages according to Ann Arbor were: II: 13%, III: 13%, IV 73%. The median number of previous therapies were 3 for Fref/pret, 2 for AIC and 2 for RT.

Note: these were younger patients, but most had advanced disease and were a poor risk lot with many previous types of treatment.

A total of 314 cycles were administered, with a median number of 3 cycles for AIC and Fref pts and a median number of 4 cycles for the RT group. Due to toxicity 73% of cycles in the Fref/pret group, 66% in the AIC and 87% in the RT group were dose-reduced. 69% of Fref/pret-pts and 58% of AIC-pts received full 6 cycles of therapy and only 40% of RT-pts completed 8 cycles of therapy. Treatment was stopped in 6 pts because of PD. Due to treatment related toxicity treatment was stopped in 16 pts (27%). Treatment related mortality was 3% (2 pts). Treatment toxicity was reported according to NCI common toxicity criteria (CTC) version 2.0. Adverse events grade 3 or 4 for anemia, neutropenia and thrombocytopenia were documented in 75%, 55% and 65% of patients, respectively. Infections were the most common non-hematologic toxicity and occurred in 67%; severe infections CTC grade 3 or 4 occurred in 28%.

Treatment was not administered with the dose intensity that was planned for. This was because of toxicity - as would be expected with so many stage C patients in the mix.


All 26 Fref/pret-pts were available for response evaluation. CHOP-R achieved 54% PR, 35% SD and 12% PD. The median progression-free survival (PFS) and median treatment-free survival (TFS) were 11 and 14 mos. OS was 27 mos with a significant difference concerning F-ref (n=15) and F-pret (n=11) pts (17 vs. 35m; p=0.05). We evaluated the response of all 15 RT-pts with 60% PR, 7% CR, 13% SD and 20% PD. The PFS was 15 mos, TFS was 17 mos and OS 27 mos. 17 AIC pts were available for response evaluation with 82% PR, 6% SD and 12% PD. The PFS and TFS were only 14 and 16 mos. The OS was 50 mos.

Note: although the PR rate was respectable, it is artificially high because only some of the pret patients would have been refractory to fludarabine and the difference between overall survival for Fref and pret was more than double and statistically significant. If patients lived long enough they could benefit from other treatment including lenolidemide, alemtuzumab and transplant.

The population had a high incidence of unfavourable genetic markers: deletion of chromosome 17p [del(17p)] was detected in 24%, del(11q) in 34% and unmutated IGHV in 70%. 85% had high levels of serum thymidine kinase (sTK > 10 U/l), and 49% had high levels of ß2-microglobulin (ß2M > 3.5 mg/l). Patients with del(17p) had an unfavourable response rate and achieved significant less a PR or CR (36% vs. 76%; p=0.03). Multivariate analyses showed that del(17p) and ECOG performance status had a negative prognostic impact on OS (p = 0.0001). Moreover the presence of a del(17p) predicted a short PFS (6 vs. 16.9 mos; p=0.001).

Note: This is of course old news, but we are now discerning other factors involved in Richter Syndrome and fludarabine refractoriness.

Conclusion:

CHOP-R achieves promising response rates in CLL patients with Fref and RT and very good response rates in patients with AIC. However, the progression-free survival and overall survival remain unsatisfactory. Therefore, CHOP-R might be used as induction therapy prior to allogeneic stem cell transplantation in physically fit patients.

Or the agents that interfere with BCR stimulation, or alemtuzumab, or lenalidemide especially early in the disease. Even Bendamustine-R (or Ofatumumab) has not been evaluated in this scenario. Still CHOP-R for AIC might be promising.

The spliceosome: a new factor in bad risk CLL

I mentioned some weeks ago that the spliceosome is going to be important in CLL. The spliceosome is an epigenetic mechanism which is involved in splicing together the separated introns of a gene identified on DNA. It had already been identified as a factor in determining the various subtypes of MDS, but it has now been recognized as an important mechanism underlying fludarabine refractoriness in CLL and also in some cases of Richter syndrome.

I have quoted from this paper from Italy in a recent BLOOD

Mutations of the SF3B1 splicing factor in chronic lymphocytic leukemia:association with progression and fludarabine-refractoriness

The clinical course of chronic lymphocytic leukemia (CLL) ranges from a very indolent
disorder with a normal lifespan, to a rapidly progressive disease leading to death. Occasionally, CLL undergoes transformation to Richter syndrome (RS). The variable clinical course of CLL is driven, at least in part, by the disease immunogenetic and molecular heterogeneity.

Despite recent advances, the genetic lesions identified to date do not entirely explain the development of severe complications, such as chemorefractoriness, which still represent unmet clinical needs. Fludarabine-refractoriness is due to TP53 disruption in ~40% of refractory cases, but in a sizeable fraction of patients the
molecular basis of this aggressive phenotype remains unclear. Recently, two independent studies of the CLL coding genome investigated at disease presentation have revealed a restricted number of mutated genes, including NOTCH1. These
studies have provided a proof of concept that, similar to other malignancies, genome-wide mutational analysis might identify novel lesions of biological and clinical relevance in CLL.

On these grounds, the authors have embarked on the investigation of the coding genome of fludarabine refractory CLL in order to identify genetic lesions associated with chemorefractoriness. The initial phases of this analysis have revealed recurrent mutations of SF3B1, a critical component of the cell spliceosome, pointing to the potential involvement of splicing regulation in CLL pathogenesis and chemo-refractoriness.

The study population comprised 3 cohorts representative of different disease phases: i) fludarabine-refractory CLL (n=59), including cases (n=11) subjected to whole exome sequencing; ii) a consecutive series of newly diagnosed and previously untreated CLL (n=301); and iii) clonally related RS (n=33; all diffuse large B cell lymphomas).

Diagnosis of CLL and of fludarabine-refractoriness were based on IWCLL-NCI criteria; RS was based on histological criteria. Peripheral blood tumor samples were obtained as follows: i) for fludarabine-refractory CLL, immediately before starting treatment to which the patient failed to respond because of stable/progressive disease; ii) for newly diagnosed and previously untreated CLL, at disease presentation. All RS studies were performed on RS diagnostic biopsies. Normal DNAs from the same patients were obtained from saliva or from purified granulocytes and confirmed to be tumor-free by PCR of tumor-specific IGHV-D-J rearrangements. Patients provided informed consent in accordance with local IRB requirements and Declaration of Helsinki. The study was approved by the Local Ethical Committee (Protocol Code 59/CE; Study Number
CE 8/11).

Mutation analysis of SF3B1 (exons 1-25, including splice sites; RefSeq NM_012433.2) was performed on PCR amplimers obtained from genomic DNA by a combination of Sanger sequencing and targeted next generation sequencing. FISH karyotype, mutation analysis of IGHV, TP53 and NOTCH1, copy number analysis, and gene expression profile analysis FISH analysis was performed using probes LSI13 and LSID13S319, CEP12, LSIp53, and LSIATM. IGHV sequences were aligned to ImMunoGeneTics directory and considered mutated if identity to corresponding germline genes was less than 98%.3, TP53 and NOTCH1 mutations were analysed by Sanger sequencing.3,7 Genome-wide DNA profiles were obtained using Affymetrix Genome-Wide Human SNP Array 6.0. Gene expression profile analysis was performed using Affymetrix HG-U133_plus2 arrays.

Statistical analysis

Overall survival was measured from date of diagnosis to date of death (event) or last followup (censoring). Treatment free survival was measured from date of diagnosis to date of progression to symptomatic disease requiring treatment according to IWCLL-NCI guidelines (event), death, or last follow up (censoring).

Results and Discussion


Following the initial observation of recurrent SF3B1 mutations in 3/11 fludarabine refractory CLL analyzed by whole exome sequencing, we performed targeted re-sequencing of the SF3B1 coding sequence and splice sites in 48 additional cases of progressive and fludarabinerefractory CLL (total number of cases analyzed: 59). SF3B1 was altered in 10/59 (17%) fludarabine-refractory CLL by missense mutations (n=9) or in-frame deletions (n=1) clustering in the HEAT3, HEAT4 and HEAT5 repeats of the SF3B1 protein. Two sites that are highly conserved inter-species (codon 662 and codon 700) were recurrently mutated in 3 and 5 cases, respectively. SF3B1 mutations were monoallelic, and were predicted to be functionally significant according to the PolyPhen-2 algorithm. These data document that mutations of SF3B1, a splicing factor that is a critical component of the spliceosome, recurrently associate with fludarabine-refractory CLL.

The biological characteristics of fludarabine-refractory CLL harboring SF3B1 mutations are in summary that mutations occurred irrespective of the IGHV mutation status, CD38 expression and ZAP70 expression. At the time of fludarabine-refractoriness, SF3B1 mutations were enriched in cases harboring a normal FISH karyotype (p=.008). Also, SF3B1 mutations distributed in a mutually exclusive fashion compared to TP53 disruption tested by deletion and/or mutation (mutual information I =0.0609; p=.046). By combining SF3B1 mutations with other genetic lesions enriched in chemorefractory cases (TP53 disruption, NOTCH1 mutations, ATM deletion), fludarabine-refractory CLL appeared to be characterized by multiple molecular alterations that, to some extent, are mutually exclusive.

To investigate whether SF3B1 mutations are restricted to chemorefractory cases, we then compared the prevalence of mutations observed at the time of fludarabine-refractoriness to the prevalence of mutations observed in other disease phases. In a consecutive series evaluated at CLL diagnosis, SF3B1 mutations were rare (17/301; 5%)and occurred irrespective of other molecular and immunogenetic features. Remarkably, 5/17 (29%) CLL mutated at diagnosis were primary fludarabine-refractory patients. In these 5 cases, TP53 disruption and NOTCH1 mutations occurred in 1 cases each. None of the 12 remaining cases harbored TP53 disruption or NOTCH1 mutations.

By univariate analysis, SF3B1 mutations showed a crude association with short treatment free survival (p<.001) and overall survival (p=.011). By multivariate analysis, the increased risk of death predicted by SF3B1 mutations was independent (HR: 3.02; 95% CI: 1.24-7.35; p=.015) of confounding clinical and biological variables. Confirmation within the frame of prospective clinical trials will be helpful to fully assess the generalization of SF3B1 mutations as a CLL prognostic marker. In CLL investigated at diagnosis, the hotspot distribution and molecular spectrum of SF3B1 mutations, as well as their mutual relationship with other genetic lesions, were similar to those observed in fludarabine-refractory CLL. SF3B1 mutations were only found in 2/33 (6.0%) clonally-related RS. Across the different disease phases investigated, mutations were confirmed to be somatically acquired in all cases (n=18) for which germline DNA was available. Among the three SF3B1 mutated cases for which serial samples were analyzed, SF3B1 mutations were acquired in 2 cases. One fludarabine-refractory CLL acquired the c.2044A>G p.K666E mutation at the time of refractoriness, and one RS acquired the c.2146A>G p.K700E mutation at the time of transformation. In the remaining case, the SF3B1 mutation was present in all disease phases. Although the relative expression of SF3B1 in CLL was higher compared to normal B-cell subsets, extensive investigation by SNP array analysis ruled out focal copy number abnormalities of SF3B1 in this leukemia (n=0/323). SF3B1 mutations were consistently absent among mature B-cell neoplasms (n=136) other than CLL. These data document that SF3B1 mutations: i) are specific for CLL among mature B-cell neoplasms; ii) occur at a low rate at CLL presentation, whereas they are enriched in fludarabine-refractory cases; iii) play a minor role in RS transformation, corroborating the notion that CLL histologic shift is molecularly distinct from chemorefractory progression without RS transformation.

The identification of SF3B1 mutations in CLL, and the recent discovery of SF3B1 mutations in myelodysplasia, points to the involvement of splicing regulation as a novel pathogenetic mechanism in hematologic malignancies. SF3B1 is a critical component of both major (U2-like) and minor (U12-like) spliceosomes, which enact the precise excision of introns from premRNA. The precise biological role of SF3B1 mutations in CLL is currently elusive, and will require dedicated studies. The pathogenicity of SF3B1 mutations in CLL is strongly supported by the clustering of these mutations in evolutionarily conserved hotspots localized within HEAT domains, which are tandemly arranged curlicue-like structures serving as flexible scaffolding on which other components can assemble. Also, the observation that SF3B1 regulates the alternative splicing program of genes controlling cell cycle progression and apoptosis points to a potential contribution of SF3B1 mutations in modulating tumor cell proliferation and survival. In addition to pathogenetic implications, SF3B1 mutations might also provide a therapeutic target for SF3B1 inhibitors, which are currently under pre-clinical development as anti-cancer
drugs.

F v FA as second line: a phase 3 trial

This report on a second line treatment for CLL from Lancet Oncology today

Fludarabine plus alemtuzumab versus fludarabine alone in patients with previously treated chronic lymphocytic leukaemia: a randomised phase 3 trial

Despite the increasing number of treatment options, chronic lymphocytic leukaemia (CLL) remains an incurable disease. Estimates of median survival range from more than 10 years for patients with early-stage CLL to less than 1 year for patients with fludarabine-resistant disease. In view of the incurable and chronic nature of CLL, and the worsening prognosis for patients as their disease becomes more advanced or refractory, the development of alternative regimens in earlier treatments is essential to improve their outcome.

Preclinical data suggested that the addition of alemtuzumab to fludarabine-based regimens could have a synergistic effect due to their complementary modes of action. In a report by Kennedy and colleagues, five of six patients with CLL who were refractory to both drugs when administered as single agents achieved remission with the combination of fludarabine and alemtuzumab.

Results from a single-group phase 2 study further suggested that fludarabine and alemtuzumab combination could improve outcomes in patients with relapsed or refractory CLL, with an overall response rate (ORR) of 83% and a median overall survival of 35·6 months. Therefore, we compared the efficacy and safety of this combination treatment with fludarabine monotherapy in patients with relapsed or refractory CLL.

The study was done in five centres in North America and 43 in Europe. Eligible patients had relapsed or refractory CLL according to the National Cancer Institute Working Group's 1996 criteria, with evidence of progressive disease that required therapy after one previous line of treatment for CLL. Patients could have had past treatment with fludarabine or alemtuzumab provided the duration of their response was longer than 12 months. Additional inclusion criteria were Binet stage A, B, or C or Rai stage I–IV disease; WHO performance status (PS) 0 or 1; life expectancy of 12 weeks or longer; age 18 years or older; anticancer treatment, major surgery, or radiation therapy more than 3 weeks before randomisation in the study; complete recovery from acute side-effects of previous therapy; and adequate renal and liver function.

Exclusion criteria were previous treatment for CLL with more than one previous regimen or the combination of fludarabine and alemtuzumab; positive Coombs test and active haemolysis; absolute neutrophil count (ANC) of less than 1·5×10e9 cells per L or platelet count of less than 75×10e9 per L, unless due to bone-marrow involvement with CLL; disorders requiring chronic use of corticosteroids; history of anaphylaxis to monoclonal antibodies; HIV positivity; evidence of active infection or history of grade 4 infection within 3 months before randomisation in the study; active second malignancy; known CNS involvement with CLL; other severe concurrent disease; progression due to a more aggressive B-cell cancer (eg, Richter's syndrome); and a history of viral hepatitis or positive hepatitis B serology in the absence of immunisation.

This study was approved by the institutional review board or ethics committee from each of the participating sites. All patients provided written informed consent before enrolment to the study.

An interactive voice response system (IVRS) was used to randomly assign patients in a 1:1 ratio to fludarabine plus alemtuzumab or fludarabine monotherapy in an open-label trial. At call-in from the site to enrol the patients, IVRS conveyed stratification data to a computer system and initiated the randomisation program. The system retrieved stratification and treatment assignment data for previously enrolled patients, and a computer-generated next random number was provided by the sponsor's statistician. The system used the minimisation method9 with the probability parameter 0·80 to assign patients to treatment. The stratification factors were study centre, Rai stage (I or II vs III or IV), disease status (relapsed vs refractory), age (≥65 vs <65 years), sex (male vs female), past exposure to fludarabine therapy (yes vs no), and maximum lymph node size (≥5 vs <5 cm or none).

During the first treatment cycle, patients in the combination group were given escalating doses of alemtuzumab; 3 mg/day, 10 mg/day, 30 mg/day, intravenously over 2 h. If grade 3 or 4 infusion-related adverse events occurred, the same dose was repeated daily until it was well tolerated (grade 2 or lower toxicity) with appropriate premedication. A maximum of 14 days were allowed for alemtuzumab escalation to 30 mg. After completion of the escalation, patients were given fludarabine; 30 mg/m2 per day, intravenously over 30 min, followed immediately by alemtuzumab (30 mg/day, intravenously over 2 h); both were administered daily for 3 days. Cycles were repeated every 28 days. After cycle 1, alemtuzumab was infused over 4–6 h for the first day of each new cycle and over 2 h during days 2 and 3. Patients randomly assigned to the fludarabine monotherapy were treated with 25 mg/m2 per day for 5 days, intravenously, over 15–30 min, every 28 days. Patients in both groups were scheduled to receive a minimum of four cycles and a maximum of six treatment cycles, depending on response and toxicity. They were assessed for response every two cycles. Patients in the fludarabine plus alemtuzumab group were administered paracetamol 500–1000 mg orally 30 min before alemtuzumab infusion for control of infusion-related events and an antihistamine 30 min before drug administration as prophylaxis for infusion-related events. Patients were premedicated with hydrocortisone (100 mg, intravenously, or equivalent steroid) just before alemtuzumab infusion during the dose escalation phase, on day 1 of each subsequent cycle, and if clinically indicated thereafter. All patients were given prophylaxis with co-trimoxazole (trimethoprim 160 mg plus sulfamethoxazole 800 mg twice a day, three times a week, orally) or equivalent and famciclovir (500 mg twice a day, orally), starting on the first day of the study treatment and continuing until CD4+ cell counts were at least 200 cells per μL.

If patients developed haematological toxicities with a recovery time (ie, retreatment criteria ANC ≥1·0×10e9 cells per L, platelet count ≥100×10e9 per L, and no active infection) from the scheduled start of the new cycle of 14 days or less (days 29–43 of previous cycle), no dose modification was required in those assigned to combination treatment or monotherapy; 15–28 days (days 44–57 of previous cycle), patients assigned to combination treatment were given fludarabine 30 mg/m2 per day plus alemtuzumab 30 mg/day for 2 days every 28 days, and those assigned to monotherapy were administered 16·75 mg/m2 per day for 5 days every 28 days; and more than 28 days (after day 57 of previous cycle), treatment was discontinued in the combination treatment or monotherapy group.

In the event of a non-haematological toxicity of grade 1 or 2, no dose modification was required with combination treatment or monotherapy; grade 3, patients assigned to combination treatment were given fludarabine 30 mg/m2 per day plus alemtuzumab 30 mg/day for 2 days every 28 days, and those assigned to monotherapy were administered 16·75 mg/m2 per day for 5 days every 28 days; if a patient recovered more than 28 days after the date of the originally scheduled start of the next treatment cycle, the patient was withdrawn from the study; grade 4, treatment was discontinued in patients assigned to combination treatment or monotherapy. Patients with a creatinine clearance of 0·50–1·17 mL/s per 1·73 m2 were treated with fludarabine at a 20% dose reduction. Other protocol-mandated reasons for treatment delay or discontinuation were neurotoxicity; serious infection; grade 3 or higher pulmonary, renal, or hepatic toxicity; autoimmune thrombocytopenia; and symptomatic autoimmune anaemia.

Patients were monitored weekly with complete blood count and testing for cytomegalovirus (with quantitative PCR on peripheral blood) during cycles 1 and 2, and every 2 weeks thereafter. Monthly complete blood count, CD4+ cell count, and testing for cytomegalovirus continued after cycle 6 until blood counts recovered or stabilised and CD4+ cell counts rose to more than 200 cells per μL. Patients who were PCR-positive for cytomegalovirus without clinical symptoms of cytomegalovirus infection or had rising viral transcripts on subsequent weekly PCR testing were treated with valganciclovir while on study treatment. Those with clinical manifestations of cytomegalovirus infection (fever or end-organ symptoms) were treated with ganciclovir for at least 10 days. Interruption of study treatment was allowed for up to 28 days before necessitating discontinuation from study participation.

Clinical, radiographic (chest radiography or CT if clinically indicated), and laboratory assessments for response or progression were done every two cycles during treatment and every 3 months after treatment until disease progression. Thereafter, patients were followed up for survival only. Patients with a clinical complete response (CR) or partial response (PR) without recovery of blood counts underwent bone-marrow assessment and testing for minimal residual disease (MRD) 2 months after the end of treatment.

The primary endpoint was progression-free survival (PFS), defined as the time of randomisation to progression or death from any cause, whichever was earlier. The primary endpoint was changed from time to progression (TTP) to a more conservative definition of PFS before any of the planned interim analyses were undertaken to make the data more comparable with data from other randomised studies of patients with CLL.

The main secondary endpoints were ORR, CR rate, overall survival, and safety. Additional, secondary endpoints were TTP, duration of response, time to alternative treatment, incidence of MRD negativity, fludarabine pharmacokinetics, and health-related quality of life. The main analysis of efficacy was based on the assessments of response and disease progression for each patient by the independent response review panel, members of which were masked to treatment assignment. Response criteria and progression were assessed according to the National Cancer Institute Working Group's 1996 guidelines for CLL; criteria for disease progression were specified in the study protocol and were in accordance with these guidelines.8 The health-related quality-of-life instrument was a five-dimensional questionnaire about health status and a visual analogue scale thermometer for self-rating current health-related quality of life. The five dimensions were mobility, self-care, usual activities, pain or discomfort, and anxiety or depression, rated according to three possible levels (no problems, some problems, and extreme problems). Exploratory analyses to investigate the effect of prespecified prognostic factors on efficacy outcomes were also undertaken.

Toxicities were graded in accordance with the National Cancer Institute Common Terminology Criteria for Adverse Events (version 3.0). All patients who were given at least one dose of study drug were included in the safety analysis.

The planned sample size for this study of 300 patients (150 per group) to observe 190 events of progression or death, irrespective of treatment group, was designed to detect a 50% improvement in PFS in either group with 80% power and a two-sided α of 0·05. Two interim analyses were planned to assess safety and efficacy at a third and two-thirds of the total planned events under the jurisdiction of a data safety monitoring board. To protect the overall α of 0·05 for the analysis of the primary endpoint, a Lan and DeMets error spending function with an O'Brien–Fleming boundary was used to allow flexibility with the timing of the interim analyses.

Differences in PFS and overall survival between the treatment groups were tested by use of the Cox proportional hazard model, stratified by Rai stage (I or II vs III or IV). Differences in ORR and CR were tested with the Cochran-Mantel-Haenzsel method stratified by Rai stage (I or II vs III or IV). The main analysis was done on an intention-to-treat (ITT) basis for all patients who were randomly assigned. To control family-wise error rate at the 0·05 level, a multiple-tests' adjustment with the Hochberg procedure12 was prespecified for the three clinically important secondary endpoints: ORR, CR, and overall survival. Statistical analyses were done with the Statistical Application Software (version 9.1.3).

The study is registered with ClinicalTrials.gov, number NCT00086580

From July, 2004, to October, 2008, 335 patients were enrolled (18 in centres in North America and 317 in Europe) and randomly assigned to fludarabine alone or with alemtuzumab. More patients than planned were enrolled to enable an analysis of potential drug–drug interactions. Six patients were not given the study treatment and therefore were not included in the safety analysis. Baseline demographics and disease characteristics used for stratification were well balanced between the treatment groups.

In both groups, patients were given a median of six treatment cycles (range 1–6), and 105 (64%) of 164 patients in the combination treatment group and 107 (65%) of 165 in the monotherapy group were given six cycles. The median cumulative dose of alemtuzumab was 583 mg (range 3–653) and fludarabine 494·5 mg/m2 (0–568·4) in the combination treatment group, and fludarabine 687·5 mg/m2 (20·6–776·5) in the monotherapy group.

Fludarabine plus alemtuzumab significantly prolonged PFS compared with fludarabine. The ORR was non-significantly higher in the combination treatment group than in the monotherapy group. The CR rate was significantly higher in the fludarabine plus alemtuzumab group than in the fludarabine alone group. The independent response review panel identified six patients in the combination treatment group and none in the monotherapy group as MRD negative (p=0·014).

With a median follow-up for all enrolled patients of 29·5 months (IQR 16·5 to 42·1 months), the median overall survival was significantly improved in the fludarabine plus alemtuzumab group, with 117 (70%) of 168 patients in the combination treatment group and 100 (60%) of 167 in the monotherapy group alive at the data cutoff or last follow-up date. After the predefined multiple testing adjustment, the comparisons between groups for CR rate and overall survival remained significant (p=0·018 and p=0·042, respectively). There was no apparent treatment difference in the quality-of-life indicators.

The significantly improved PFS in patients treated with combination treatment compared with monotherapy was consistent for all prespecified subgroups, including those judged to be high risk (advanced disease and older patients). Patients with advanced disease (Rai stage III or IV) who were given combination treatment had a longer median PFS than did those given fludarabine. The ORR and CR rate were also significantly higher. Notably, patients with Rai stage III or IV who were given fludarabine plus alemtuzumab also had significantly improved median overall survival compared with those treated with fludarabine alone, indicating survival benefit in favour of the combination treatment. Improvement in overall survival was not noted in patients with Rai stage I or II CLL (HR 1·07, 95% CI 0·62–1·84; p=0·82). There was evidence of differential treatment benefit in terms of overall survival with the combination treatment in the patients who were Rai stage III or IV compared with Rai stage I or II (p=0·011). In older patients (age ≥65 years), median PFS was significantly longer with the combination treatment than with fludarabine alone. Median overall survival for this older population was not reached in the group assigned to fludarabine plus alemtuzumab, whereas it was 40·9 months in the monotherapy group.

161 (98%) of 164 patients in the fludarabine plus alemtuzumab group and 149 (90%) of 165 in the fludarabine group had all-cause adverse events. In the combination treatment group, non-haematological all-cause adverse events occurring in more than 10% of patients were pyrexia, chills, rash, infusion-related reactions, urticaria, cytomegalovirus PCR positivity, and nausea. In the monotherapy group, none of the non-haematological all-cause adverse events arose in more than 10% of patients. The most common all-cause serious adverse events that arose in more than 2% of patients in the fludarabine plus alemtuzumab group were neutropenia, febrile neutropenia, pneumonia, pyrexia, thrombocytopenia, diarrhoea, and leucopenia. In the fludarabine group, these were febrile neutropenia and anaemia.

Ten patients in the fludarabine plus alemtuzumab group and 12 in the fludarabine group died as a result of adverse events (irrespective of cause). During the treatment period (date of first dose to 30 days after last dose), four patients in the combination treatment group and seven in the monotherapy group died as a result of an adverse event. The causes of these deaths were similar (acute respiratory and circulatory insufficiency [n=2], acute haemolysis [n=1], and cardiopulmonary insufficiency [n=1] in the fludarabine plus alemtuzumab group; disease related [n=2], acute respiratory and circulatory insufficiency [n=2], septic shock syndrome [n=1], acute myocardial infarction [n=1], and pulmonary oedema in the fludarabine group [n=1]). Of these, three fatal drug-related adverse events occurred in the combination treatment group (acute haemolysis [n=1] and acute respiratory and circulatory insufficiency [n=2]) and three in the fludarabine group (acute respiratory and circulatory insufficiency [n=2] and septic shock syndrome [n=1]).

The overall incidence of severe haematological toxicity (defined as laboratory changes from less than grade 3 at baseline to grade 3 or greater post-baseline, or changes from grade 3 at baseline to grade 4 post-baseline) during the treatment period are shown in table 5. The median time to recovery of CD4+ cell counts (>200 cells per μL) was 3·0 months (95% CI 2·7–4·7) in the fludarabine plus alemtuzumab group and 2·0 months (1·8–2·6) in the fludarabine group.

All-cause infections occurred in 67 (41%) of 164 patients in the combination treatment group and in 58 (35%) of 165 in the monotherapy group. The types and severity of all infections were similar in the two groups with the exception of lower-respiratory-tract infections (26 [16%] vs eight [5%]) and viral infections (19 [12%] vs ten [6%]), which occurred more frequently in the fludarabine plus alemtuzumab group. Additionally, the incidences of infections that were greater than grade 3 were similar in both groups—19 patients in the combination treatment group (grade 3 [n=17], grade 4 [n=1, pneumonia], grade 5 [n=1, pneumonia]) versus 17 in the monotherapy group (grade 3 [n=10], grade 4 [n=3], grade 5 [n=4]). Grade 4 infections in the fludarabine group were Escherichia coli gastroenteritis (n=1) and sepsis (n=2), and grade 5 infections were pneumococcal sepsis (n=1), pyelonephritis (n=1), septic shock (n=1), and oral fungal infection (n=1).

Cytomegalovirus-PCR-positive tests were reported in 19 (12%) asymptomatic patients in the fludarabine plus alemtuzumab group and in one (<1%) asymptomatic patient in the fludarabine group. Study drug was not discontinued for any of the patients with asymptomatic cytomegalovirus PCR positivity. The median time to first occurrence of a PCR-positive test was 30 days (range 20–52) for patients in the fludarabine plus alemtuzumab group; only one patient in the fludarabine monotherapy group had cytomegalovirus PCR positivity (on day 69 after the start of treatment). Symptomatic cytomegalovirus infection was reported in four patients (2%) only in the fludarabine plus alemtuzumab group, and their symptoms were fever (n=2), hepatitis (n=1), and fever, fatigue, malaise, and leucopenia (n=1). One patient discontinued study treatment because of symptomatic cytomegalovirus infection. All patients with symptomatic cytomegalovirus infections were treated with ganciclovir and recovered without sequelae.

121 (74%) of 164 patients in the fludarabine plus alemtuzumab group had at least one potentially alemtuzumab infusion-related event (defined as having at least one drug-related adverse event out of the following preferred terms: chills, pyrexia, nausea, vomiting, rash, urticaria, hypotension, bronchospasm, cytokine release syndrome, or infusion-related reaction) during cycles 1–6 compared with 24 (15%) of 165 in the fludarabine group. Potentially alemtuzumab infusion-related adverse events were most common in the initial treatment cycles for the fludarabine plus alemtuzumab group. For chills, pyrexia, nausea, and urticaria, the incidences were highest in cycle 1 and seemed to show a general reduction with progression from cycle 1 to cycle 6 for the fludarabine plus alemtuzumab group. The incidences of bronchospasm, infusion-related reaction, vomiting, and cytokine release were also highest in cycle 1, but the total incidence was low, and therefore a pattern could not be discerned for the fludarabine plus alemtuzumab group. The incidences of hypotension (two [1%]) and rash (21 [13%]) did not seem to be related to the cycle. Furthermore, most of the infusion-related events were mild in the combination and monotherapy groups (grade 1 and 2, 102 [62%] and 22 [13%], respectively), one patient in the fludarabine plus alemtuzumab group had a grade 4 event (pyrexia), and there were no fatal infusion-related events.

No clinically relevant differences in incidence of adverse events were noted between patients with Rai stage I or II versus III or IV, patients aged 65 years and older versus younger than 65 years, or male versus female patients. Furthermore, the safety profile of combination treatment in patients 65 years and older was similar to that of the overall patient population.

The combination of fludarabine and alemtuzumab resulted in a significant improvement in PFS, CR rate, and overall survival compared with fludarabine alone in patients with previously treated relapsed or refractory CLL. Although the difference in ORR between these regimens was not significant, the improvement in PFS and overall survival shows the clinical benefit of the combination treatment. This combination also seemed to provide significant clinical benefit to patients with advanced disease (Rai stage III or IV), a particularly important subset of patients for whom further investigation is warranted.

When compared with single-agent fludarabine, treatment with fludarabine plus alemtuzumab resulted in a similar overall frequency and severity of infectious complications, similar frequency of grade 3 or 4 neutropenia and thrombocytopenia, a lower frequency of anaemia, and, as expected, a higher frequency of lymphopenia. The rate of cytomegalovirus PCR positivity and infections in the combination treatment group was 14% which is lower than the previously reported frequency of 68% with first-line alemtuzumab monotherapy given three times a week. Although there was a discrepancy in grade 3 or 4 adverse events between treatment groups, most of these events were anticipated and they were related to the mechanism of action of alemtuzumab (particularly lymphopenia or leucopenia and infusion-associated reactions). Despite the difference in the occurrence of grade 3 or 4 adverse events, the percentage of patients who discontinued treatment or deaths during treatment was similar in both groups.

Despite the recent advances in treatment options for first-line treatment for patients with CLL, the disease remains incurable, thus treatment decisions require that benefit-to-risk assessments are undertaken for each patient. The National Comprehensive Cancer Network guidelines and European Society of Medical Oncology guidelines suggest consideration of a variety of therapeutic regimens to treat patients with CLL throughout the course of their illness. The substantial heterogeneity of patients with CLL with respect to disease burden, age, and comorbid illnesses means that several options should be available.

Systematic review

A search of the literature identified an earlier phase 2 trial in which excellent results were reported for three times weekly alemtuzumab used in combination with 4-weekly fludarabine, suggesting superadditive effects. At the time of initiation of this trial, results from another phase 2 trial by a German chronic lymphocytic leukaemia (CLL) study group were available, combining alemtuzumab with fludarabine in a 4-week schedule in patients with relapsed and refractory CLL; they also reported high response rates with tolerable toxicity. Since the monthly fludarabine plus alemtuzumab schedule had not been previously investigated in a large, randomised phase 3 study, we designed this study for further assessment of combination treatment.

The findings of our randomised phase 3 study suggest that the monthly administration of alemtuzumab plus fludarabine results in excellent response rates and prolonged progression-free survival and overall survival with a tolerable side-effect profile. Furthermore, the total dose of each drug is substantially reduced and is more convenient for patients. Noteworthy is that patients, especially those with advanced Rai stages, benefited from this treatment approach. Thus, we view this combination as an important treatment option for patients with relapsed or refractory CLL.

Additionally, at the time the protocol was initiated, no combination regimens were approved for use in previously treated patients with CLL and few randomised controlled studies have been undertaken in patients with relapsed or refractory CLL. O'Brien and colleagues reported an ORR of 65% with fludarabine plus cyclophosphamide and 80% with fludarabine plus cyclophosphamide plus oblimersen in patients with relapsed or refractory CLL. It has been reported that in previously treated patients with CLL, compared with fludarabine plus cyclophosphamide, the three-drug combination of fludarabine plus cyclophosphamide plus rituximab extended median PFS (21·9 months vs 27·0 months), and increased ORR (49% vs 61%) and CR rates (3% vs 9%) as assessed by independent review. This comparability is important because fludarabine plus cyclophosphamide and fludarabine plus cyclophosphamide plus rituximab are increasingly used in the front-line setting; additional novel treatment regimens are needed for second-line therapy.

Treatment of CLL has been evolving over the period this study was undertaken. For patients with relapsed or refractory CLL, various guidelines provide options for treatment but no globally recognised standard of care exists. However, fludarabine-based combination regimens have been increasingly used as first-line or subsequent treatments. Although no conclusion can be drawn about the benefit of the combination treatment in the subset of patients with previous exposure to fludarabine because of the small sample size (25 in fludarabine plus alemtuzumab group and 26 in fludarabine monotherapy group], the HR of 0·82 suggests that the combination treatment is beneficial. Additionally, the significant overall treatment benefit noted from all the enrolled patients suggests that the combination treatment provided benefit to all enrolled patients previously given different types of treatment. Also, cytogenetic testing was not required in the initial stages of the study and was added midway through the study. Therefore, cytogenetic data were available for 57% of 335 patients, restricting the statistical precision of analyses in subgroups defined on the basis of these data, and restricting the ability to make conclusions about any effect of cytogenetics on response.

For second-line therapy, the fludarabine plus alemtuzumab regimen has several potential advantages. First, unlike fludarabine plus cyclophosphamide and fludarabine plus cyclophosphamide plus rituximab, the fludarabine plus alemtuzumab regimen spares patients from additional exposure to alkylating drugs, which theoretically might be associated with serious early and late toxicities, such as leukaemia possibly associated with secondary therapy. Second, patients treated with fludarabine plus alemtuzumab had a lower exposure to each drug than with the commonly used dosing regimen when each drug is used alone. The combination regimen uses 50% less alemtuzumab and 30% less fludarabine than the dosing regimen approved by the US Food and Drug Administration for single drug use. Last, the dosing schedule for alemtuzumab of 3 days per month in the fludarabine plus alemtuzumab regimen improves patient convenience compared with the standard dosing regimen of three times per week for up to 12 weeks.

The fludarabine plus alemtuzumab combination provides clinical benefits with an acceptable safety profile in previously treated patients with CLL when compared with single-agent fludarabine. This combination might become an important additional treatment option for patients with relapsed or refractory CLL

del 13 q14: size matters

In Leukemia Research on line

Chronic lymphocytic leukemia (CLL) is a highly heterogeneous disease which has proven amenable to subtyping through genomic microarray analysis. Initially, 13q14 deletions as an isolated finding were associated with a favorable prognosis. However, recent evidence has revealed significant heterogeneity within the 13q14 deletion subtype, thus, there is a clear clinical need for more precise stratification of 13q14 deletions at the genomic level. The minimal deleted region (MDR) includes: DLEU2, DLEU7, MIR15A/MIR16-1 and part of DLEU1. Recent studies suggest that in addition to the MDR, the size of the deletion and the involvement of the nearby tumor suppressor gene RB1 serve as an independent prognostic biomarker for disease progression. Nine individuals in whom a 13q deletion had previously been identified by bacterial artificial chromosome (BAC) array were re-analyzed using the Cancer Cytogenomics Microarray Consortium's consensus design on an Agilent (Santa Clara, CA) 180K oligonucleotide platform. Based on the size and location of the 13q14 deletion, cases were further classified as having type (smaller, not including RB1) or type II (larger, including RB1) deletions, as described by Ouilette et al. (Cancer Res, 2008). Type I deletions were seen in 77% of cases, and Type II deletions in 22%. There was a single case of a biallelic 13q14 deletion. Deleted regions ranged in size from 1.0 to 9.8 Mb. Unlike older BAC technologies that are subject to limited resolution, the CCMC 180K oligonucleotide array allowed for further clarification of 13q deletion cases, providing valuable clinical and prognostic information for CLL.

What happened to the Respect Trial?

Trials for patients with early stage CLL approved by the British NCRI
RESPECT – (CLL203)

This is a 40 patient single arm study to investigate the use of Lenalidomide in patients with early stage CLL with 2 or more poor prognostic factors. Christie Hospital is managing the trial. There are stringent stopping rules. Screening conducted by HMDS in Leeds. Biobanking samples will be collected from all screened patients.

Current Status

The trial opened and recruited 2 pts but recruitment is currently suspended following the release of 2nd malignancy data following the use of Lenalidomide. Recruitment had been slow prior to suspension of recruitment. It was asked whether the group if they were still interested in the trial and whether the design was still viable. These issues were discussed by the group; problems include: there is limited data on the use of this toxic treatment (lenalidomide) in patients who may otherwise not require treatment; the variable rate of progression of Stage A patients, even those with a poor prognosis and many stage A are treated in DGHs. However, it is still an interesting question. To wait for official feedback from Celgene before assessing the full impact on the protocol, the risk-benefit analysis and the re-opening the study.

An illustrative difficult case

This is the first illustrative case report sent in by a reader on which I will attempt to give advice.

Please remember that I am only licensed to treat patients in the UK and I would never give specific advice to a patient without seeing them and taking a full history, completing a full examination and ordering appropriate tests. This post is therefore for illustrative purposes only to show how CLL experts think about difficult cases.

I received a Binet Stage A CLL diagnosis at age 33 with a p53 mutation (although no, 17p-) and unmutated IGVH. My current hematologist is recommending FCR+Campath as a frontline when I come off of W&W.

It seems the FCR portion doesn't work especially well, if at all, with a dysfunctional p53 pathway so does the CFAR treatment make sense?

Would the HDMP+Campath, Revlimid+a CD20 monoclonal, or a BtK Inhibitor treatment be more appropriate prior to looking at a RIC SCT and if so, which of the three is most preferred?

Finally, my WBC is around 48, Hg 15.5 and platelets around 115. My spleen is 14 cm and the other nodes are slightly enlarged, but not very noticeable. I run 10km a day with no fatigue or any other B symptoms. If the platelets go below 100 what is the best way to distinguish between marrow failure and a spleen that is sequestering the platelets--BMB? Would the treatment for thrombocytopenia be the same irrespective of the cause of the platelets going below 100? In other words, failing marrow, I presume would automatically be reason a chemo-immuno therapy right away, but would chemo-immuno therapy be appropriate if the marrow is producing sufficient RBC, but the spleen is keeping those cells from circulating?


The first question to ask is does being diagnosed at 33 make a difference?

The answer is that young people with CLL are likely to live longer than older people but they will die at an earlier age than those who are diagnosed later. This is really obvious since even if a person of 33 lives for 25 years he would still die at 58, whilst the average age of diagnosis for CLL is 69. On the other hand there is on record at least one case diagnosed in his thirties who went for 52 years and never required treatment.

The second question is, given there are bad prognostic markers in this case, should treatment be started now?

The answer is that this question is still moot and clinical trials have been organized to answer it. But the advice being given for now is to watch and wait until the IWCLL/NCR criteria are met; unless you embark on one of the clinical trials designed to answer the question.

The third question is how serious are the poor prognostic markers?

The answer is that IGVH mutations are an index characteristic of the disease. On average people with unmutated IGHV genes require treatment within 2-3 years and are dead within 8 years. Remember, averages don't describe every patient in the cohort and there is considerable variation. In my series some patients with unmutated IGHV genes lived for 15 years and went more than 5 years without starting treatment. I wrote my paper in 1999 and treatment has certainly improved since then. As with all patients, young patients live longer than old patients, so treatment is likely to be an issue at some stage and it is well to think about the future.

TP53 mutations are a different matter. Del 17p is a more certain sign of future danger since some TP53 mutations do not have such a malign effect. We have a small population of patients with TP53 abnormalities who have survived for many years without treatment. However, most of these have mutated IGHV genes.

The next question is about how to treat TP53 abnormal CLL.

This is still difficult. FCR acts poorly and FCM is not that advantageous when used first line although it has a good record second line. CFAR, again does not have a brilliant track record and Bendamustine + R is not useful either. HDMP + Campath has a good response rate, but does induce severe immunodeficiency and the best results are from England. Don't have it unless you get it from an experienced hospital.

Revlimid probably does not have a role, but the BCR inhibitors like CAL 101 and PCI32765 look promising. Stem cell allografting is the most likely to produce a cure, especially at 33, but it has a high mortality and morbidity rate.

All in all, I would say that the field is progressing rapidly and I would hold off treatment until more information is available.

Next question: how important is a spleen of 14cm.

Answer: it is not important at all. This has to be a CT measurement and the normal in a man is 12 cm. This slight increase in size is seen in virtually all CLL patients and it is a good reason not to do CT scans in all patients with CLL. They are expensive, they give you unnecessary radiation and oncologists who are more used to dealing with lymphoma rather than CLL, misinterpret them. In your case the lowered platelet count is almost certainly due to bone marrow infiltration and this could be confirmed by a BMB. Although I don't recommend one; this is an unnecessary investigation in most cases of CLL.

The lowered platelet count is not a reason for starting chemoimmunotherapy straight away; that would be dependent on the rate of fall. At 110 you are not in any danger.

The Spliceosome 2

See what I mean?

The genetic lesions identified in chronic lymphocytic leukemia (CLL) do not entirely
recapitulate the disease pathogenesis and the development of serious complications, such as chemorefractoriness. While investigating the coding genome of fludarabine-refractory CLL, we observed that mutations of SF3B1, encoding a splicing factor and representing a critical component of the cell spliceosome, were recurrent in 10/59 (17%) fludarabine-refractory cases, with a frequency significantly higher than that observed in a consecutive CLL cohort sampled at diagnosis (17/301, 5%; p=.002). Mutations were somatically acquired, were generally represented by missense nucleotide changes, clustered in selected HEAT repeats of the SF3B1 protein, recurrently targeted three hotspots (codons 662, 666 and 700), and predicted poor prognosis. In fludarabine refractory CLL, SF3B1 mutations and TP53 disruption distributed in a mutually exclusive fashion (p=.046). The identification of SF3B1 mutations points to splicing regulation as a novel pathogenetic mechanism of potential clinical relevance in CLL.

CLL patients refractory to FCR and alemtuzumab

My daughter is currently the registrar in charge of lymphomas at Oxford. She tells me that the most difficult-to-treat patients are the refractory CLLs, even though she has to manage Burkitt's lymphoma and other high grade lymphomas as well as patients having autografts. In the journal, Value in Health, there is an article written to describe the current pattern of care and resource utilisation in Europe for patients with fludarabine-refractory chronic lymphocytic leukaemia (CLL) who are either refractory to alemtuzumab (DR) or ineligible for alemtuzumab due to bulky lymphadenopathy (BFR)

Data are from an interim analysis of 37 patients, 62% (n=23) DR and 38% (n=14) BFR. Median time between first diagnosis and index refractory diagnosis was 5.2 years. Average age was 62.2 (range 41-77), 76% were male and average number of co-morbidities was 2.2. Many patients (59%) died during the post index period with median survival following diagnosis of refractory disease being 6.2 months. In the pre-index period the average number of pharmacotherapy regimens was 0.9 (range 0-3) and in the post-index period 1.4 (range 1-4). During the 24 month review period the most frequent single agent regimens were alemtuzumab (38% patients) and methylprednisolone (19%). Patients receiving combination therapy most frequently received rituximab (43%), mainly in combination with CHOP (16%), fludarabine/cyclophosphamide (11%), and bendamustine (8%). 89% of patients experienced at least one treatment related adverse event, including infection (76%), anaemia (76%), thrombocytopenia (68%) and neutropenia (62%). Average number of post-index A&E visits was 0.8 and in-patient stays 1.9, the majority (86%) relating to CLL or its treatment. Average inpatient stay was 11.2 days. Most patients (81%) had multiple diagnostic investigations (average 11.5), predominantly CT scans (average 6.1) and X-rays (average 2.0).

This study demonstrates the high economic burden and continuing unmet clinical needs of patients with fludarabine-refractory CLL disease in Europe

IWCLL 2011

It's a good job that I didn't go to the IWCLL meeting in San Diego - the meeting was being held in Houston!

The feedback that I had is that it was a different kind of meeting with many more young people there. There were a few talks by the old-stagers, but a some of these were described as rather old-hat. There is very little point in presenting old data at a meeting like this. There were no reports of major clinical trials, in particular no reports of trials of CAL-101 or PCI32765, though Susan O'Brien did give a case report on each with spectacular results.

Bendamustine + rituximab looks like it is performing better than I thought it would, so one must ask the question why the drug company needed to cheat in its clinical trials.

The Binet-Rai medal was presented to my old friend Guillaume (or Guillermo or just plain William) Dighiero. He was the guiding light in the French Trials and has done some important molecular studies. He now works at the Pasteur Institute in Uruguay