Are we closer to a standard of care for Richter's syndrome? Novel treatments on the horizon.

INTRODUCTION: The therapeutic landscape for chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) has significantly evolved over the past decade with dramatically improved outcomes with the introduction of targeted therapies. This unfortunately has not been the case for Richter transformation (RT), the histologic transformation to a more aggressive lymphoma, most typically diffuse large B-cell lymphoma (DLBCL). As such, RT continues to be one of the most challenging complications of CLL/SLL. Historically, RT has a poor response to treatment, with a minority reaching complete remission (CR) and overall survival (OS) being less than a year. AREAS COVERED: The focus of this review is to discuss the effectiveness of commonly used regimens, and review existing data for emerging regimens being examined in ongoing clinical trials to improve prognosis and outcomes in patients with RT. Despite extensive efforts to optimize therapies for RT, there is still no generalized consensus on either first-line treatment regimens or regimens in the relapsed/refractory setting. RT continues to carry a high mortality rate without durable response to current therapeutic agents. EXPERT OPINION: Ongoing and future research may identify novel treatment approaches that will eventually improve outcomes for patients with RT. The optimal care for RT patients is a clinical trial, when feasible.

Prognostic impact of chronic lymphocytic leukemia comorbidity index in a young population: a real-world evidence study of a national gulf region cohort.

In chronic lymphocytic leukaemia (CLL), comorbidities assessed by the CLL comorbidity index (CLL-CI) have been associated with outcomes in Western cohorts. We conducted a retrospective analysis of an unselected Middle Eastern cohort of newly diagnosed CLL patients seen at the Kuwait Cancer Control Center (n = 300). Compared to Western studies, these Middle Eastern patients were diagnosed at a younger age (median of 59) and had a higher comorbidity burden (69% non-low risk CLL-CI). A higher CLL-CI score was independently associated with significantly shorter event-free survival and greater risk of death. Our analysis demonstrates that CLL-CI is a valuable tool for comorbidity assessment and prognostic influence in (relatively young) Middle Eastern CLL patients.

Improved Survival of Patients With Chronic Lymphocytic Leukemia Between 1998-2022, Including the Era of Target Therapies With BCL2 and BTK Inhibitors.

BACKGROUND/AIM: The treatment for chronic lymphocytic leukemia (CLL) has changed dramatically over the last two decades. The current study aimed to investigate the impact on overall survival (OS) and time to next treatment (TTT) among CLL patients from 1998 to 2022. PATIENTS AND METHODS: The cohort was based on data obtained from electronic medical records of Maccabi, the second largest healthcare organization in Israel. All included patients were diagnosed with CLL based on the IWCLL criteria and complete clinical, laboratory, and treatment data were available. The study encompassed 3,964 patients diagnosed with CLL during the specified study period. RESULTS: Patients with CLL who required therapy were divided into three eras based on the dominant treatment approach: chemotherapy alone before 2010, therapy with chemotherapy and anti-CD20 between 2010 and 2017, and therapy with targeted agents between 2017 and 2022. Median OS was 4.1 years, 7.5 years, and not reached, respectively. The six-year OS rates were 40%, 55%, and 69%, respectively, (p=0.0001). The median time to the next treatment improved from 5.5 years before 2010, to 8.3 between 2010-2017, to not reached after 2017 (p=0.0021). CONCLUSION: Marked improvements in survival subsequent to fundamental changes in first-line therapy were found in patients with CLL from before 2010 to after 2017.

Evaluating population-level outcomes in Chronic Lymphocytic leukemia in the era of novel therapies using the SEER registry.

In the last decade, novel agents such as BTK and BCL-2 inhibitors have revolutionized treatment of CLL/SLL, with clinical trials showing improved overall survival compared to chemotherapeutic agents. However, studies examining whether they have improved overall survival at the population level are lacking. We evaluated this by conducting a retrospective analysis of CLL/SLL patients registered in the National Cancer Institute's surveillance epidemiology and end results (SEER) database, analyzing overall survival (OS) in periods pre- and post-availability of novel agents, along with demographic information. Our results showed that median OS significantly improved over time [7.8 years (2000-2005), 9.1 years (2006-2013), and not reached (2014-2018) (p < 0.001)]. Compared to diagnosis in 2014-2018, diagnosis in earlier periods was associated with higher mortality risk (2000-2005-HR 1.32, 95 % CI 1.28-1.37, p < 0.001: 2006-2013-HR 1.09, 95 % CI 1.06-1.13, p < 0.001). Lower mortality risk was seen in patients age < 85 years whereas median household income of <$75000 was associated with higher mortality. Our study provides real-world data suggesting a possible multifactorial contribution to improvement in survival, including availability of novel agents, better monitoring, and supportive care. They also show discrepancies in overall survival for CLL/SLL patients due to socioeconomic status and demographic factors.

Outcomes with ibrutinib in patients with chronic lymphocytic leukaemia: Results from the German multicentre REALITY study.

OBJECTIVES: To assess treatment adherence, effectiveness and safety outcomes of patients with chronic lymphocytic leukaemia (CLL) receiving ibrutinib in a real-world setting. METHODS: Patients enrolled in REALITY were ≥18 years with a confirmed diagnosis of CLL and were receiving ibrutinib as a first-line (1L), 2L or ≥3L therapy. Treatment retention, adherence, progression-free survival (PFS), overall survival (OS) and time to next therapy were assessed at 1 and 2 years overall, by typology and by cytogenetic subgroups. PFS and OS were analysed using Kaplan-Meier methods. RESULTS: Exactly 302 patients were enrolled across 57 sites in Germany, from January 2017 to July 2021. One-year retention rates were 69.9% overall (primary endpoint), 77.9% for 1L patients, and 77.6%/78.8% for high-risk patients with del17p/TP53. At 2 years, PFS/OS rates were 77.8%/90.7% overall (1L, 82.7%/90.4%), and were consistent across cytogenetic subgroups. PFS rates were higher for 1L versus ≥3L patients. Patients with the low-acceptance/low-control typology at baseline were less likely to retain treatment at 1 year versus the high-acceptance/high-control typology. No new safety signals were observed. CONCLUSIONS: The REALITY study provides further evidence of the effectiveness and safety of ibrutinib in patients with CLL in a real-world setting, particularly in earlier treatment lines.

Tumor mutational load is prognostic for progression to therapy among high-count monoclonal B-cell lymphocytosis.

ABSTRACT: High-count monoclonal B-cell lymphocytosis (HCMBL) is a precursor condition to chronic lymphocytic leukemia (CLL). We have shown that among individuals with HCMBL, the CLL-International Prognostic Index (CLL-IPI) is prognostic for time-to-first therapy (TTFT). Little is known about the prognostic impact of somatically mutated genes among individuals with HCMBL. We sequenced DNA from 371 individuals with HCMBL using a targeted sequencing panel of 59 recurrently mutated genes in CLL to identify high-impact mutations. We compared the sequencing results with that of our treatment-naïve CLL cohort (N = 855) and used Cox regression to estimate hazard ratios and 95% confidence intervals (CIs) for associations with TTFT. The frequencies of any mutated genes were lower in HCMBL (52%) than CLL (70%). At 10 years, 37% of individuals with HCMBL with any mutated gene had progressed requiring treatment compared with 10% among individuals with HCMBL with no mutations; this led to 5.4-fold shorter TTFT (95% CI, 2.6-11.0) among HCMBL with any mutated gene vs none, independent of CLL-IPI. When considering individuals with low risk of progression according to CLL-IPI, those with HCMBL with any mutations had 4.3-fold shorter TTFT (95% CI, 1.6-11.8) vs those with none. Finally, when considering both CLL-IPI and any mutated gene status, we observed individuals with HCMBL who were high risk for both prognostic factors had worse prognosis than patients with low-risk CLL (ie, 5-year progression rate of 32% vs 21%, respectively). Among HCMBL, the frequency of somatically mutated genes at diagnosis is lower than that of CLL. Accounting for both the number of mutated genes and CLL-IPI can identify individuals with HCMBL with more aggressive clinical course.

Real-world evidence of obinutuzumab and venetoclax in previously treated patients with chronic lymphocytic leukemia or small lymphocytic lymphoma.

Venetoclax-obinutuzumab (Ven-O) is frequently administered off-label in relapsed/refractory (r/r) CLL/SLL where venetoclax-rituximab is the approved regimen. We conducted this retrospective, real-world study to evaluate Ven-O in r/r CLL/SLL. Between 7/2019 and 6/2022, 40 patients with r/r CLL/SLL on Ven-O were included. The median age was 72, 28.2% had TP53 mutation and/or 17p deletion, median number of prior therapies was 1 (range, 1-6), and 55% had prior BTK inhibitor exposure. The overall response rate was 90% (complete response [CR] or CR with incomplete marrow recovery in 27.5% and partial response in 62.5%) of patients, and the 2-year progression-free survival was 81.2% (95% CI, 69.5-94.8). Therapy was well tolerated. No laboratory or clinical TLS occurred with venetoclax (Howard criteria). One (3%) patient experienced laboratory TLS with obinutuzumab initiation. In summary, this retrospective cohort study demonstrated that Ven-O achieves frequent, durable responses and can be safely administered in r/r CLL/SLL.

Prediction of outcomes for high-count monoclonal B lymphocytosis using an epigenetic and immunogenetic signature.

ABSTRACT: Monoclonal B-cell lymphocytosis (MBL) progresses to chronic lymphocytic leukemia (CLL) requiring therapy at 1% to 5% per year. Improved prediction of progression would greatly benefit individuals with MBL. Patients with CLL separate into 3 distinct epigenetic subtypes (epitypes) with high prognostic significance, and recently the intermediate epitype has been shown to be enriched for high-risk immunoglobulin lambda variable (IGLV) 3-21 rearrangements, impacting outcomes for these patients. Here, we employed this combined strategy to generate the epigenetic and light chain immunoglobulin (ELCLV3-21) signature to classify 219 individuals with MBL. The ELCLV3-21 high-risk signature distinguished MBL individuals with a high probability of progression (39.9% and 71.1% at 5 and 10 years, respectively). ELCLV3-21 improved the accuracy of predicting time to therapy for individuals with MBL compared with other established prognostic indicators, including the CLL international prognostic index (c-statistic, 0.767 vs 0.668, respectively). Comparing ELCLV3-21 risk groups in MBL vs a cohort of 226 patients with CLL revealed ELCLV3-21 high-risk individuals with MBL had significantly shorter time to therapy (P = .003) and reduced overall survival (P = .03) compared with ELCLV3-21 low-risk individuals with CLL. These results highlight the power of the ELCLV3-21 approach to identify individuals with a higher likelihood of adverse clinical outcome and may provide a more accurate approach to classify individuals with small B-cell clones.

Outcomes in Patients with High-Risk Features after Fixed-Duration Ibrutinib plus Venetoclax: Phase II CAPTIVATE Study in First-Line Chronic Lymphocytic Leukemia.

PURPOSE: The CAPTIVATE study investigated first-line ibrutinib plus venetoclax for chronic lymphocytic leukemia in 2 cohorts: minimal residual disease (MRD)-guided randomized discontinuation (MRD cohort) and Fixed Duration (FD cohort). We report outcomes of fixed-duration ibrutinib plus venetoclax in patients with high-risk genomic features [del(17p), TP53 mutation, and/or unmutated immunoglobulin heavy chain (IGHV)] in CAPTIVATE. PATIENTS AND METHODS: Patients received three cycles of ibrutinib 420 mg/day then 12 cycles of ibrutinib plus venetoclax (5-week ramp-up to 400 mg/day). FD cohort patients (n = 159) received no further treatment. Forty-three MRD cohort patients with confirmed undetectable MRD (uMRD) after 12 cycles of ibrutinib plus venetoclax received randomized placebo treatment. RESULTS: Of 195 patients with known status of genomic risk features at baseline, 129 (66%) had ≥1 high-risk feature. Overall response rates were >95% regardless of high-risk features. In patients with and without high-risk features, respectively, complete response (CR) rates were 61% and 53%; best uMRD rates: 88% and 70% (peripheral blood) and 72% and 61% (bone marrow); 36-month progression-free survival (PFS) rates: 88% and 92%. In subsets with del(17p)/TP53 mutation (n = 29) and unmutated IGHV without del(17p)/TP53 mutation (n = 100), respectively, CR rates were 52% and 64%; uMRD rates: 83% and 90% (peripheral blood) and 45% and 80% (bone marrow); 36-month PFS rates: 81% and 90%. Thirty-six-month overall survival (OS) rates were >95% regardless of high-risk features. CONCLUSIONS: Deep, durable responses and sustained PFS seen with fixed-duration ibrutinib plus venetoclax are maintained in patients with high-risk genomic features, with similar PFS and OS to those without high-risk features. See related commentary by Rogers, p. 2561.

Obinutuzumab (GA-101), ibrutinib, and venetoclax (GIVe) frontline treatment for high-risk chronic lymphocytic leukemia.

Despite considerable treatment advances with targeted therapies for patients with chronic lymphocytic leukemia (CLL) deemed high-risk [del(17p) and/or TP53 mutation], the outcome is still inferior compared with other CLL patients. Combining multiple agents with distinct mechanisms of action may further improve outcomes. CLL2-GIVe is an open-label, multicenter trial which enrolled patients with previously untreated CLL with del(17p) and/or TP53 mutation. Patients received induction therapy with obinutuzumab (GA-101), ibrutinib, and venetoclax (GIVe) for cycles 1 through 6 and consolidation therapy with venetoclax and ibrutinib for cycles 7 through 12. Ibrutinib monotherapy was continued for cycles 13 through 36 in patients not reaching a complete response (CR) with serial undetectable minimal residual disease (uMRD) after consolidation. The primary endpoint was CR rate at cycle 15 (final restaging). Secondary endpoints included MRD, survival, and safety. All 41 patients enrolled between September 2016 and August 2018 received study treatment and were included in efficacy and safety populations. With a CR rate of 58.5% at cycle 15, the primary endpoint was met (95% CI: 42.1-73.7; P < .001). At final restaging, 78.0% of patients had uMRD in peripheral blood (PB); 65.9% of patients had uMRD in bone marrow (BM). Estimated progression-free survival (PFS) and overall survival (OS) rates at 24 months were both 95.1%. Adverse events were reported in all patients; most were low grade (grade ≥3: 23.9%). Two deaths were reported (cardiac failure and ovarian carcinoma), neither related to study treatment. The CLL2-GIVe treatment regimen has a manageable safety profile and is a first-line treatment of good efficacy for patients with high-risk CLL.

Real world risk of infusion reactions and effectiveness of front-line obinutuzumab plus chlorambucil compared with other frontline treatments for chronic lymphocytic leukemia.

BACKGROUND: Chronic lymphocytic leukemia (CLL) is the most common type of leukemia in North America. Previous studies have shown improved progression free survival (PFS) and response rates in unfit patients treated with obinutuzumab compared to other regimens. The aim of this study was to evaluate the obinutuzumab-chlorambucil regimen in the context of historical treatments and first-dose infusion reactions at CancerCare Manitoba (CCMB). METHODS: A retrospective chart review was conducted for patients treated with obinutuzumab from January 1, 2014 to December 31, 2017 at CCMB. A minimum data set was extracted for patients treated with other front-line therapies. Descriptive statistics were used to evaluate patient demographics, toxicity, duration and dosing of obinutuzumab treatment. Kaplan-Meier curves were used to evaluate time-to-next-treatment (TTNT), overall survival (OS) and PFS for patients treated with obinutuzumab. A multivariable logistic regression model was used to investigate associations between infusion related reactions (IRRs) and age at treatment, pre-treatment lymphocyte count, cumulative illness rating scale (CIRS) and receipt of prior chemotherapy. RESULTS: Forty seven percent of patients receiving frontline therapy received chlorambucil and obinutuzumab. Sixty-seven patients were treated with obinutuzumab and consisted of 36 males (53.7%) and 31 females (46.3%) with 29 patients (43.3%) over age 75 years. Rates of grade 3 and 4 obinutuzumab IRRs were lower (6%) compared to the CLL11 clinical trial (20%) due to local practices including slower infusion rates and using chlorambucil before starting obinutuzumab treatment. Many patients had difficulty tolerating the full dosage of chlorambucil. Only 26 patients (38.8%) had their dose of chlorambucil escalated to the full dose of 0.5 mg/kg. In addition, only 18 patients (26.9%) received all doses of obinutuzumab and all 12 doses of chlorambucil. CONCLUSIONS: In summary, first dose infusion reactions with obinutuzumab can be markedly reduced by using chlorambucil to decrease the lymphocyte count before obinutuzumab and by using a very slow initial obinutuzumab infusion rate. Modifications in chlorambucil dosing and obinutuzumab administration can improve tolerance without significant loss in efficacy.

Dynamic Bayesian networks for prediction of health status and treatment effect in patients with chronic lymphocytic leukemia.

Chronic lymphocytic leukemia (CLL) is the most common blood cancer in adults. The course of CLL and patients' response to treatment are varied. This variability makes it difficult to select the most appropriate treatment regimen and predict the progression of the disease. This work was aimed at developing and validating dynamic Bayesian networks (DBNs) to predict changes of the health status of patients with CLL and progression of the disease over time. Two DBNs were developed and implemented i.e. Health Status Network (HSN) and Treatment Effect Network (TEN). Based on the literature data and expert knowledge we identified relationships linking the most important factors influencing the health status and treatment effects in patients with CLL. The developed networks, and in particular TEN, were able to predict probability of survival in patients with CLL, which was in line with the survival data collected in large medical registries. The networks can be used to personalize the predictions, taking into account a priori knowledge concerning a particular patient with CLL. The proposed approach can serve as a basis for the development of artificial intelligence systems that facilitate the choice of treatment that maximizes the chances of survival in patients with CLL.

Survival, causes of death, and the prognostic role of comorbidities in chronic lymphocytic leukemia in the pre-ibrutinib era: A population-based study.

OBJECTIVE: To evaluate temporal trends in survival and causes of death in patients with chronic lymphocytic leukemia (CLL) in a nationwide study. METHODS: The cohort consisted of 13,009 Swedish CLL patients diagnosed 1982-2013. Relative survival (RS) and excess mortality rate ratios (EMRR) with 95% confidence intervals (95% CIs) were estimated using flexible parametric survival models. Cause-specific hazard ratios (HRs) were estimated for the linear effect of 10-year increase in year of diagnosis. RESULTS: The excess mortality decreased comparing 2003-2013 to 1982-1992 (EMRR = 0.53, 95% CI 0.48-0.58). The 5-year RS increased between 1982 and 2012 for patients >51 years at diagnosis and improved for patients ≤51 years after 2002. The rate of CLL-specific deaths decreased over time (HR = 0.78, 95% CI 0.75-0.81). Compared to patients with no comorbidity, patients with 1 and 2+ Charlson Comorbidity Index points had HR = 1.35 (95% CI 1.25-1.45) and HR = 1.47 (95% CI 1.37-1.57) for CLL-related mortality, respectively. CONCLUSION: Survival in CLL patients improved in the era of chemoimmunotherapy, and this was largely explained by reduced CLL-related mortality. The increased rate of CLL-related mortality in patients with comorbidities emphasizes the importance of the newer and better tolerated targeted therapy.

Chronic lymphocytic leukaemia/small lymphocytic lymphoma treatment with rituximab and high-dose methylprednisolone, revisited.

High-dose methylprednisolone plus rituximab (R-HDMP) is a useful treatment in chronic lymphocytic leukaemia/small lymphocytic lymphoma (CLL/SLL) patients unfit for chemo-immunotherapy and has proven its utility on the treatment of CLL/SLL complicated by auto-immune cytopenias. We performed a retrospective, single-centre study, of CLL/SLL patients treated with R-HDMP for 9 years. Thirty-nine patients were included, median age at time of treatment was 77 years. Most patients had stage Rai III/IV and Binet C disease. Twenty-eight patients had relapsed/refractory disease at time of treatment with a median of 1 previous line of therapy; 53.8% had prior exposure to fludarabine and 25% to rituximab. Grade 3-4 neutropenia and thrombocytopenia were recorded in 10.2% and 17.9% patients, respectively. While on treatment, 51.3% had documented infectious complications, but no other non-haematological toxicities grades 3-4 were identified. Overall response rate was 64%. Median overall survival and progression-free survival were 24 and 13 months, respectively. Twenty four patients relapsed and 16 received another line of treatment after R-HDMP, with median time to next treatment of 13.5 months. Thirteen out of the 24 patients improved performance status and were subsequently considered fit for chemo-immunotherapy. R-HDMP is a valuable option for elderly and frail patients, with low risk of severe myelotoxicity and other severe adverse events. It was shown to work as a bridge to other lines of treatment, including chemo-immunotherapy.

COVID-19 severity and mortality in patients with CLL: an update of the international ERIC and Campus CLL study.

Patients with chronic lymphocytic leukemia (CLL) may be more susceptible to Coronavirus disease 2019 (COVID-19) due to age, disease, and treatment-related immunosuppression. We aimed to assess risk factors of outcome and elucidate the impact of CLL-directed treatments on the course of COVID-19. We conducted a retrospective, international study, collectively including 941 patients with CLL and confirmed COVID-19. Data from the beginning of the pandemic until March 16, 2021, were collected from 91 centers. The risk factors of case fatality rate (CFR), disease severity, and overall survival (OS) were investigated. OS analysis was restricted to patients with severe COVID-19 (definition: hospitalization with need of oxygen or admission into an intensive care unit). CFR in patients with severe COVID-19 was 38.4%. OS was inferior for patients in all treatment categories compared to untreated (p < 0.001). Untreated patients had a lower risk of death (HR = 0.54, 95% CI:0.41-0.72). The risk of death was higher for older patients and those suffering from cardiac failure (HR = 1.03, 95% CI:1.02-1.04; HR = 1.79, 95% CI:1.04-3.07, respectively). Age, CLL-directed treatment, and cardiac failure were significant risk factors of OS. Untreated patients had a better chance of survival than those on treatment or recently treated.