Acalabrutinib, venetoclax and obinutuzumab in relapsed CLL: Final efficacy and ctDNA analysis of the CLL2-BAAG trial.

The phase 2 CLL2-BAAG trial tested the measurable residual disease (MRD)-guided triple combination of acalabrutinib, venetoclax and obinutuzumab after an optional bendamustine debulking in 45 patients with relapsed/refractory CLL (one patient was excluded from the analysis due to a violation of exclusion criteria). MRD was measured by flow cytometry (FCM, undetectable MRD <10-4) in peripheral blood (PB) and circulating tumor DNA (ctDNA) by digital droplet PCR (ddPCR) of variable-diversity-joining (VDJ) rearrangements and CLL-related mutations in plasma. MRD recurrence was defined as detectable ctDNA and/or MRD ≥10-4 after achieving both uMRD/undetectable ctDNA. The median number of previous treatments was 1 (range 1-4), 18 patients (40%) had received a BTK inhibitor (BTKi) and/or venetoclax prior to inclusion, 14/44 (31.8%) had TP53 aberrations, 34 (75.6%) had unmutated IGHV. With a median observation time of 36.3 months and all patients off treatment for a median of 21.9 months, uMRD <10-4 in PB was achieved in 42/45 patients (93.3%) at any time point, including 17/18 (94.4%) previously exposed to venetoclax/BTKi and 13/14 (92.9%) with TP53 aberrations. The estimated three-year progression-free and overall survival rates were 85.0% and 93.8%. Overall 585 paired FCM/ctDNA samples were analyzed and 18 MRD recurrences (5 with and 13 without clinical progression) occurred after the end of treatment. Twelve were first detected by ctDNA, three by FCM and three synchronously. Patients with earlier detection by ctDNA appeared to have genetically higher risk disease. In conclusion, time-limited MRD-guided acalabrutinib, venetoclax and obinutuzumab achieved deep remissions in almost all patients with relapsed/refractory CLL. The addition of ctDNA-based analyses to FCM MRD assessment seems to improve early detection of relapses. ClinicalTrials.gov Identifier: NCT03787264.

Reassessing the chronic lymphocytic leukemia International Prognostic Index in the era of targeted therapies.

ABSTRACT: We evaluated the chronic lymphocytic leukemia International Prognostic Index (CLL-IPI) in patients with CLL treated first line with targeted drugs (n = 991) or chemoimmunotherapy (n = 1256). With a median observation time of 40.5 months, the 3-year progression-free survival (PFS) rates for targeted drug-treated patients varied by CLL-IPI risk group: 96.5% (low), 87.6% (intermediate), 82.4% (high), and 78.7% (very high). Differences between consecutive CLL-IPI risk groups were observed for intermediate vs low and high vs intermediate, but not very high vs high. CLL-IPI factors ß2-microglobulin, immunoglobulin heavy variable (IGHV) status, and TP53 status each retained prognostic value for PFS. The 3-year overall survival (OS) rates by CLL-IPI risk groups were 100%, 96%, 93.9%, and 89.4%, respectively, with no differences between consecutive risk groups. Age, Binet stage, ß2-microglobulin, and TP53 status each retained prognostic value for OS. In chemoimmunotherapy patients (median observation time, 66.9 months), 3-year PFS rates for CLL-IPI risk groups were 78.1%, 51.4%, 40.1%, and 16.5%, respectively; corresponding 3-year OS rates were 97.4%, 93.1%, 81.8%, and 57.3%. In a matched-pair analysis, PFS differences in targeted therapies (n = 812) vs chemoimmunotherapy (n = 812) across all risk groups and OS differences in all but patients at low risk were demonstrated. The CLL-IPI maintains its prognostic value in predicting PFS outcomes with targeted drugs, but its impact in predicting survival appears diminished. Targeted therapies showed enhanced outcomes over chemoimmunotherapy, highlighting their effectiveness across various risk groups. Our findings support ongoing assessment of prognostic tools in CLL treatment evolution. These trials were registered at www.ClinicalTrials.gov as #NCT02345863, #NCT02401503, #NCT02689141, #NCT02445131, #NCT02758665, #NCT02950051, #NCT02242942, #NCT00262782, #NCT00281918, and #NCT01010061.

COVID-19 in patients with hematologic malignancy.

The coronavirus infectious disease (COVID-19) shows a remarkable symptomatic heterogeneity. Several risk factors including advanced age, previous illnesses, and a compromised immune system contribute to an unfavorable outcome. In patients with hematologic malignancy, the immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is significantly reduced explaining why the mortality rate of hematologic patients hospitalized for a SARS-CoV-2 infection is about 34%. Active immunization is an essential pillar to prevent SARS-CoV-2 infections in patients with hematologic malignancy. However, the immune response to SARS-CoV-2 vaccines may be significantly impaired, as only half of patients with hematologic malignancy develop a measurable antiviral antibody response. The subtype of hematologic malignancy and B cell-depleting treatment predict a poor immune response to vaccination. Recently, antiviral drugs and monoclonal antibodies for pre-exposure or postexposure prophylaxis and for early treatment of COVID-19 have become available. These therapies should be offered to patients at high risk for severe COVID-19 and vaccine nonresponders. Importantly, as the virus evolves, some therapies may lose their clinical efficacy against new variants. Therefore, the ongoing pandemic will remain a major challenge for patients with hematologic malignancy and their caregivers who need to constantly monitor the scientific progress in this area.

The CLL12 trial: ibrutinib vs placebo in treatment-naïve, early-stage chronic lymphocytic leukemia.

Observation is the current standard of care for patients with early-stage asymptomatic chronic lymphocytic leukemia (CLL), as chemotherapy-based interventions have failed to prolong survival. We hypothesized that early intervention with ibrutinib would be well tolerated and lead to superior disease control in a subgroup of early-stage patients with CLL. The phase 3, double-blind, placebo-controlled CLL12 trial randomly assigned asymptomatic, treatment-naïve Binet stage A CLL patients at increased risk of progression in a 1:1 ratio to receive ibrutinib (n = 182) or placebo (n = 181) at a dose of 420 mg daily. At a median follow-up of 31 months, the study met its primary endpoint by significantly improving event-free survival in the ibrutinib group (median, not reached vs 47.8 months; hazard ratio = 0.25; 95% confidence interval = 0.14-0.43, P < .0001). Compared with placebo, ibrutinib did not increase overall toxicity, yielding similar incidence and severity of adverse events (AEs). The most common serious AEs were atrial fibrillation, pneumonia, and rash in the ibrutinib group, and basal cell carcinoma, pneumonia, and myocardial infarction in the placebo group. Ibrutinib-associated risk for bleeding (33.5%) was decreased by prohibiting the use of oral anticoagulants through an amendment of the study protocol and by avoiding CYP3A4 drug-drug interactions. Ibrutinib confirms efficacy in CLL patients at an early stage with an increased risk of progression. However, the results do not justify changing the current standard of "watch and wait." This trial was registered at www.clinicaltrials.gov as #NCT02863718.

Hybrid immunity to SARS-CoV-2 in patients with chronic lymphocytic leukemia.

OBJECTIVE: Preventing severe COVID-19 remains a priority globally, particularly in the immunocompromised population. As shown in healthy individuals, immunity against SARS-CoV-2 can be yielded by previous infection, vaccination, or both (hybrid immunity). The objective of this observation study was to investigate hybrid immunity in patients with chronic lymphocytic leukemia (CLL). METHODS/RESULTS: Blood samples of six patients with CLL were collected 55 days after fourth COVID-19 vaccination. All patients had a SARS-CoV-2 infection within 12 months before the second booster (fourth vaccination). SARS-CoV-2 spike receptor binding domain (RBD)-specific IgG antibodies were detectable in 6/6 (100.0%) CLL patients after four compared to 4/6 (66.7%) after three vaccinations. The median number of SARS-CoV-2 spike-specific T cells after repeated booster vaccination plus infection was 166 spot-forming cells (SFC) per million peripheral blood mononuclear cells. Overall, 5/5 (100%) studied patients showed a detectable increase in T cell activity. CONCLUSION: Our data reveal an increase of cellular and humoral immune response in CLL patients after fourth COVID-19 vaccination combined with SARS-CoV-2 infection, even in those undergoing B cell-depleting treatment. Patients with prior vaccination failure now show a specific IgG response. Future research should explore the duration and effectiveness of hybrid immunity considering various factors like past infection and vaccination rates, types and numbers of doses, and emerging variants.

Durable remissions following combined targeted therapy in patients with CLL harboring TP53 deletions and/or mutations.

Fifty-one of 189 evaluable patients from 3 prospective phase 2 trials evaluating a sequential targeted treatment had high-risk chronic lymphocytic leukemia (CLL) with a 17p deletion, TP53 mutation, or both. Twenty-seven patients started treatment with bendamustine debulking before induction and maintenance treatment, which was ibrutinib/ofatumumab (IO) in 21 patients, ibrutinib/obinutuzumab (IG) in 13, and venetoclax/obinutuzumab (AG) in 17. The primary end point was overall response rate after 8 months of induction treatment, which was 81%, 100%, and 94% for IO, IG, and AG, respectively. Minimal residual disease (MRD) was undetectable (uMRD) in peripheral blood (<10-4 by flow cytometry) in 0%, 23%, and 82% of patients, respectively. Median progression-free survival (PFS) was 45 months. Seventeen patients discontinued maintenance treatment due to uMRD: 9 progressed, 2 died without progression (median PFS, 28 months after discontinuation of treatment), and 6 remained in remission after a median observation time of 46 months (range, 6-47 months) after treatment discontinuation. Thus, MRD-guided fixed-duration therapies combining obinutuzumab with venetoclax or ibrutinib can induce deep and durable remissions in CLL patients with high-risk genetic lesions, which can persist after treatment discontinuation (due to a predefined fixed-duration or MRD-guided early termination). The median PFS was 45 months. These trials were registered at www.clinicaltrials.gov as #NCT02345863, #NCT02401503, and #NCT02689141.

International prognostic score for asymptomatic early-stage chronic lymphocytic leukemia.

Most patients with chronic lymphocytic leukemia (CLL) are diagnosed with early-stage disease and managed with active surveillance. The individual course of patients with early-stage CLL is heterogeneous, and their probability of needing treatment is hardly anticipated at diagnosis. We aimed at developing an international prognostic score to predict time to first treatment (TTFT) in patients with CLL with early, asymptomatic disease (International Prognostic Score for Early-stage CLL [IPS-E]). Individual patient data from 11 international cohorts of patients with early-stage CLL (n = 4933) were analyzed to build and validate the prognostic score. Three covariates were consistently and independently correlated with TTFT: unmutated immunoglobulin heavy variable gene (IGHV), absolute lymphocyte count higher than 15 × 109/L, and presence of palpable lymph nodes. The IPS-E was the sum of the covariates (1 point each), and separated low-risk (score 0), intermediate-risk (score 1), and high-risk (score 2-3) patients showing a distinct TTFT. The score accuracy was validated in 9 cohorts staged by the Binet system and 1 cohort staged by the Rai system. The C-index was 0.74 in the training series and 0.70 in the aggregate of validation series. By meta-analysis of the training and validation cohorts, the 5-year cumulative risk for treatment start was 8.4%, 28.4%, and 61.2% among low-risk, intermediate-risk, and high-risk patients, respectively. The IPS-E is a simple and robust prognostic model that predicts the likelihood of treatment requirement in patients with early-stage CLL. The IPS-E can be useful in clinical management and in the design of early intervention clinical trials.

Bendamustine, followed by ofatumumab and ibrutinib in chronic lymphocytic leukemia (CLL2-BIO): primary endpoint analysis of a multicenter, open-label phase-II trial.

The introduction of targeted agents has revolutionized the treatment of chronic lymphocytic leukemia but only few patients achieve complete remissions and minimal residual disease negativity with ibrutinib monotherapy. This multicenter, investigator-initiated phase-II study evaluates a sequential treatment with two cycles of bendamustine debulking for patients with a higher tumor load, followed by ofatumumab and ibrutinib induction and maintenance treatment. An all-comer population, irrespective of prior treatment, physical fitness and genetic factors was included. The primary endpoint was the investigator assessed overall response rate at the end of induction treatment. Of 66 patients enrolled, one patient with early treatment discontinuation was excluded from the efficacy analysis as predefined by the protocol. Thirty-nine patients (60%) were treatment-naive and 26 patients (40%) had relapsed/refractory CLL, 21 patients (32%) had a del(17p) and/or TP53 mutation and 45 patients (69%) had an unmutated IGHV status. At the end of the induction, 60 of 65 patients (92%) responded and 9 (14%) achieved minimal residual disease negativity (<10-4) in peripheral blood. No unexpected or cumulative toxicities occurred, most common CTC °III/IV adverse events were neutropenias, anaemia, infusion-related reactions, and diarrhoea. This sequential treatment of bendamustine debulking, followed by ofatumumab and ibrutinib was well tolerated without unexpected safety signals and showed a good efficacy with an overall response rate of 92%. Ongoing maintenance treatment aims at deeper responses with minimal residual disease negativity. However, ibrutinib should still be used as a single agent outside clinical trials. Clinicaltrials.gov number: NCT02689141.

Immune Dysfunction in Patients with Chronic Lymphocytic Leukemia and Challenges during COVID-19 Pandemic.

The novel severe acute respiratory syndrome coronavirus (SARS-CoV-2) has been first described in December 2019 in Wuhan, China, and has led to a worldwide pandemic ever since. Initial clinical data imply that cancer patients are particularly at risk for a severe course of SARS-CoV-2. In patients with chronic lymphocytic leukemia (CLL), infections are a main contributor to morbidity and mortality driven by an impaired immune system. Treatment initiation is likely to induce immune modulation that further increases the risk for severe infections. This article aims to give an overview on pathogenesis and risk of infectious complications in patients with CLL. In this context, we discuss current data of SARS-CoV-2 infections in patients with CLL and how the pandemic impacts their management.

COVID-19 complicated by parainfluenza co-infection in a patient with chronic lymphocytic leukemia.

The number of people suffering from the new coronavirus SARS-CoV-2 continues to rise. In SARS-CoV-2, superinfection with bacteria or fungi seems to be associated with increased mortality. The role of co-infections with respiratory viral pathogens has not yet been clarified. Here, we report the course of COVID-19 in a CLL patient with secondary immunodeficiency and viral co-infection with parainfluenza.

Rapid response infrastructure for pandemic preparedness in a tertiary care hospital: lessons learned from the COVID-19 outbreak in Cologne, Germany, February to March 2020.

The coronavirus disease (COVID-19) pandemic has caused tremendous pressure on hospital infrastructures such as emergency rooms (ER) and outpatient departments. To avoid malfunctioning of critical services because of large numbers of potentially infected patients seeking consultation, we established a COVID-19 rapid response infrastructure (CRRI), which instantly restored ER functionality. The CRRI was also used for testing of hospital personnel, provided epidemiological data and was a highly effective response to increasing numbers of suspected COVID-19 cases.

Mode of progression after first line treatment correlates with outcome of chronic lymphocytic leukemia (CLL).

In CLL, progressive disease (PD) following remission after first line treatment can present with varying phenotypes. We hypothesized that the mode of PD correlates with clinical outcomes. Data from three phase III trials of the German CLL Study Group (GCLLSG) (CLL8, CLL10, CLL11) including a total of 2159 patients receiving first line (immuno)-chemotherapy (FCR, FC, CLB, CLB-R, CLB-Ob) were analyzed. Patients were categorized as "ALC" if PD was due to increasing absolute lymphocyte count, or as "Ly" if due to lymphadenopathy. A group of 241 patients progressed with ALC, and 727 progressed with Ly, including 329 who progressed on both modalities. In fit patients, median TTNT after PD in the Ly group was 12.3 months vs 17.0 months in the ALC group (HR 1.299 [1.036-1.628]; P = .024). Median OS after PD was 45.1 months in the Ly group and 42.4 months in the ALC group (HR=1.023 [0.753-1.389]; P = .885). For unfit patients, median TTNT in the Ly group was 11.7 months vs 21.4 months in the ALC group (HR 1.357 [1.051-1.753]; P = .019). Median OS was 42.8 months in the Ly group and not reached in the ALC group (HR 1.851 [1.280-2.677]; P = .001). Patients in the Ly group more frequently showed impairment of quality of life (QoL). This analysis demonstrates that patients with progressive lymphadenopathy have a significantly shorter TTNT, OS and less favorable QoL. Our findings might help physicians to better estimate the clinical course of a progressing CLL patient.

Bendamustine followed by obinutuzumab and venetoclax in chronic lymphocytic leukaemia (CLL2-BAG): primary endpoint analysis of a multicentre, open-label, phase 2 trial.

BACKGROUND: Targeted agents such as the type II anti-CD20 antibody obinutuzumab and the B-cell lymphoma-2 antagonist venetoclax have shown impressive therapeutic activity in chronic lymphocytic leukaemia. The CLL2-BAG trial was initiated to investigate the combination of these two agents in patients with chronic lymphocytic leukaemia. METHODS: In this ongoing multicentre, open-label, investigator-initiated phase 2 trial, patients (aged ≥18 years) with chronic lymphocytic leukaemia requiring treatment according to the 2008 International Workshop on Chronic Lymphocytic Leukemia (IWCLL) criteria and an Eastern Cooperative Oncology Group performance status of 0-2 were enrolled at 16 sites in Germany. Patients with a relevant tumour load (absolute lymphocyte count ≥25 000 cells per µL or lymph nodes with a diameter of ≥5 cm) received sequential treatment of debulking with two cycles of bendamustine (70 mg/m2 intravenously on days 1 and 2 of each of the two 28-day cycles), followed by induction and maintenance with obinutuzumab (1000 mg intravenously on days 1-2, 8, and 15 of the first induction cycle, every 4 weeks in induction cycles 2-6, and every 12 weeks in the maintenance phase) and oral venetoclax (starting in induction cycle 2 with 20 mg/day, with a weekly dose escalation over 5 weeks to the target dose of 400 mg/day). The primary endpoint was the proportion of patients achieving an overall response by investigator assessment at the end of induction treatment. All patients who received at least two induction cycles were included in the efficacy analyses and all patients who received at least one dose of study drug were included in the safety analyses. This study is registered with ClinicalTrials.gov, number NCT02401503. FINDINGS: Between May 6, 2015, and Jan 4, 2016, 66 patients were enrolled (35 treatment naive and 31 with relapsed or refractory disease), three of whom were excluded from the efficacy analysis because they received fewer than two induction cycles. Of the remaining 63 patients in the efficacy-evaluable population, 34 patients (54%) were treatment naive and 29 (46%) had relapsed or refractory disease. At data cutoff (Feb 28, 2017), all patients had completed induction treatment. At the end of the induction, 60 (95%) of 63 patients (95% CI 87-99) had responded, including all 34 patients in the treatment-naive cohort and 26 [90%] of 29 relapsed or refractory patients. The most common grade 3-4 adverse events during debulking were neutropenia and anaemia (five [11%] of 47 patients each), and thrombocytopenia and infection (three [6%] each). The most common grade 3-4 adverse events during induction were neutropenia (29 [44%] of 66 patients), infection (nine [14%]), thrombocytopenia (eight [12%]), infusion-related reactions (five [8%]), and secondary primary malignancy (four [6%]). 89 serious adverse events, including 69 related to study treatment, were reported. These serious adverse events were also mainly infections (four cases in four patients during debulking and 18 cases in 11 patients during induction) and cytopenia (four cases in four patients during debulking and ten cases in seven patients in induction). Five relapsed or refractory patients died: three cases of sepsis were deemed related to study treatment, whereas two deaths from Richter's transformation were not. INTERPRETATION: The sequential application of bendamustine and obinutuzumab combined with venetoclax caused no unexpected or cumulative toxicities. The high proportion of patients who achieved overall responses, both treatment-naive and relapsed or refractory patients irrespective of physical fitness and genetic risk factors, compare favourably to established chronic lymphocytic leukaemia therapies. Further follow-up will help to define whether the remissions with eradication of minimal residual disease achieved with this combination are durable after treatment discontinuation. FUNDING: F Hoffmann-La Roche and AbbVie.

Outcome of patients aged 80 years or older treated for chronic lymphocytic leukaemia.

Clinical management of chronic lymphocytic leukaemia (CLL) in patients aged ≥80 years is based on limited evidence due to the lack of published information. Therefore, we analysed CLL patients aged ≥80 years using data from seven phase III clinical trials of the German CLL Study Group. Among 3552 participants, 152 were ≥80 years old at initiation of first-line study treatment. Median age was 82 years (range 80-90). Concomitant diseases were present in 99% of the patients, with a median cumulative illness rating scale score of 8 (0-18). Chemoimmunotherapy with chlorambucil-obinutuzumab (CLB-OB) or chlorambucil-rituximab (CLB-R) was administered to 61 (40%) and 56 (37%) patients. The remaining patients received CLB (n = 19) or fludarabine (F, n = 10), F/cyclophosphamide (FC, n = 1), FC/rituximab (FCR, n = 2) or bendamustine/rituximab (BR, n = 3). Rates of grade 3 or 4 neutropenia and infections were 35% and 13%. Overall response rate was 77% with 13% complete remissions. Median progression-free survival and treatment-free survival were 17·2 and 32·3 months, respectively. Median overall survival was 48·3 months; adverse events (22%) and progressive CLL (16·4%) were the most frequent causes of death. These findings suggest that anti-leukaemic treatment including chemoimmunotherapy is feasible and efficacious in ≥80-year-old CLL patients. However, this group of patients lives for a shorter time than age-matched controls of the general population.

Long-term remissions after FCR chemoimmunotherapy in previously untreated patients with CLL: updated results of the CLL8 trial.

Despite promising results with targeted drugs, chemoimmunotherapy with fludarabine, cyclophosphamide (FC), and rituximab (R) remains the standard therapy for fit patients with untreated chronic lymphocytic leukemia (CLL). Herein, we present the long-term follow-up of the randomized CLL8 trial reporting safety and efficacy of FC and FCR treatment of 817 treatment-naïve patients with CLL. The primary end point was progression-free survival (PFS). With a median follow-up of 5.9 years, median PFS were 56.8 and 32.9 months for the FCR and FC group (hazard ratio [HR], 0.59; 95% confidence interval [CI], 0.50-0.69, P < .001). Median overall survival (OS) was not reached for the FCR group and was 86.0 months for the FC group (HR, 0.68; 95% CI, 0.54-0.89, P = .001). In patients with mutated IGHV (IGHV MUT), FCR improved PFS and OS compared with FC (PFS: HR, 0.47; 95% CI, 0.33-0.68, P < .001; OS: HR, 0.62; 95% CI, 0.34-1.11, P = .1). This improvement remained applicable for all cytogenetic subgroups other than del(17p). Long-term safety analyses showed that FCR had a higher rate of prolonged neutropenia during the first year after treatment (16.6% vs 8.8%; P = .007). Secondary malignancies including Richter's transformation occurred in 13.1% in the FCR group and in 17.4% in the FC group (P = .1). First-line chemoimmunotherapy with FCR induces long-term remissions and highly relevant improvement in OS in specific genetic subgroups of fit patients with CLL, in particular those with IGHV MUT. This trial was registered at www.clinicaltrials.gov as #NCT00281918.

CLL2-BXX Phase II trials: sequential, targeted treatment for eradication of minimal residual disease in chronic lymphocytic leukemia.

AIM: Four Phase II trials (clinical trials numbers: NCT02345863, NCT02401503, NCT02445131 and NCT02689141) evaluate a different combination of targeted agents in an all-comer population of approximately 60 patients with chronic lymphocytic leukemia irrespective of prior treatment, physical fitness and genetic risk factors. Patients with a higher tumor load start with a debulking treatment with bendamustine. The subsequent induction and maintenance treatment with an anti-CD20 antibody (obinutuzumab or ofatumumab) and a targeted oral agent (ibrutinib, idelalisib or venetoclax) are continued until achievement of a complete response and minimal residual disease negativity. CONCLUSION: This strategy represents a new era of chronic lymphocytic leukemia therapy where chemotherapy is increasingly replaced by targeted agents and treatment duration is tailored to the patient's individual tumor load and response.