Obinutuzumab plus chlorambucil versus ibrutinib in previously untreated chronic lymphocytic leukemia patients without TP53 disruptions: A real-life CLL campus study

Innovative Combinations, Cellular Therapies and Bispecific Antibodies for Chronic Lymphocytic Leukemia: A Narrative Review

In the last few years, several agents targeting molecules that sustain the survival and the proliferation of chronic lymphocytic leukemia (CLL) cells have become clinically available. Most of these drugs target surface proteins, such as CD19 or CD20, via monoclonal or bispecific monoclonal antibodies (BsAbs), CAR T cells, intracellular proteins like BTK by using covalent or non-covalent inhibitors or BCL2 with first or second generation BH3-mimetics. Since the management of CLL is evolving quickly, in this review we highlighted the most important innovative treatments including novel double and triple combination therapies, CAR T cells and BsAbs for CLL. Recently, a large number of studies on novel combinations and newer strategic options for CLL therapy have been published or presented at international conferences, which were summarized and linked together. Although the management of treatment with a single continuous agent is easier, the emergence of protein mutations, long-term toxicities and costs are important concerns that favor the use of a fixed duration therapy. In the future, a measurable residual disease (MRD)-guided treatment cessation and MRD-based re-initiation of targeted therapy seems to be a more feasible approach, allowing identification of the patients who might benefit from continuous therapy or who might need a consolidation with BsAbs or CAR T cells to clear the neoplastic clone.

Generic ibrutinib a potential cost-effective strategy for the first-line treatment of chronic lymphocytic leukaemia

Though the chronic lymphocytic leukaemia (CLL) management options in India are still limited compared to the novel drug options in resource-rich settings, the availability of less costly generics and the government health insurance scheme has enabled many patients to access the newer drugs in India. The current study compared the cost-effectiveness and cost-utility of existing initial management options for the progression-free survival (PFS) time horizon from the patient's perspective. A two-health-state, PFS and progressive disease, Markov model was assumed for three regimens (generics): ibrutinib monotherapy, bendamustine-rituximab (B-R), and rituximab-chlorambucil (RClb) used as the frontline treatment of CLL patients in India. All costs, utilization of services, and consequences data during the PFS period were collected from interviewing patients during follow-up visits. The transition probability (TP) and average PFS information were obtained from landmark published studies. EQ-5D-5L questionnaires were utilized to assess the quality of life (QoL). Quality-adjusted life years (QALY) were measured during the PFS period. The incremental cost-effectiveness ratio (ICER) and incremental cost-utility ratio (ICUR) were studied. Upon analysis, the entire monetary expense during the PFS time was ₹1581964 with ibrutinib, ₹171434 with B-R, and ₹91997 with RClb treatment arm. Pooled PFS and QALY gain was 10.33 and 8.28 years for ibrutinib, 4.08 and 3.53 years for the B-R regimen, and 1.33 and 1.23 years in RClb arms, respectively. Ibrutinib's ICER and ICUR were ₹214587.32 per PFS year gain and ₹282384.86 per QALY gain when assessed against the B-R regimen. Ibrutinib also performed better in ICER and ICUR against the RClb arm with ₹157014.29 per PFS year gain and ₹200413.6 per QALY gain. In conclusion, generic ibrutinib is a cost-effective initial line of management compared to other commonly used treatment regimes in resource-limited settings.

Which is the top player for the cardiovascular safety? ibrutinib vs. obinutuzumab in CLL

Introduction: Ibrutinib, a Bruton's tyrosine kinase (BTK) inhibitor, is authorized for the treatment of chronic lymphocytic leukemia (CLL). This study aims to explore the cardiac safety profile of ibrutinib in comparison with obinutuzumab. Methods: A retrospective pharmacovigilance study was conducted on data retrieved from the European pharmacovigilance database (Eudravigilance) from 1 January 2014 to 30 September 2022. To compare the reporting frequency of cardiovascular events among ibrutinib, obinutuzumab, and the combination of both. Results: A total of 2 291 CV cases were retrieved, of which 1965 were related to ibrutinib, 312 to obinutuzumab, and 14 to the combination. Most cases referred to patients aged ≥65 years (N = 1,454; 63.47%) and male (N = 1,497; 65.34%). Most cases were serious (N = 2,131; 93.02%). The most reported events were: atrial fibrillation (N = 913; 31.31%) and haemorrhage (N = 201; 6.89%). A higher reporting frequency of CV events was found when ibrutinib was compared to obinutuzumab (ROR, 3.22; 95% CI, 2.89-3.60) or combination (ROR, 1.77; 95% CI, 1.11-2.83). A lower reporting was observed when obinutuzumab was compared to combination (ROR, 0.55; 95% CI, 0.34-0.88). Discussion: A higher reporting frequency of CV events in patients exposed to ibrutinib in comparison with obinutuzumab was found. Further studies are needed to better explore the safety of ibrutinib.

First-Line Treatment of Older Patients with CLL: A New Approach in the Chemo-Free Era

Bruton tyrosine kinase inhibitors (BTKi) and the BCL2 inhibitor venetoclax, with or without the anti-CD20 monoclonal antibody Obinutuzumab, represent the preferred options for the first-line therapy of CLL because they are more effective and may improve quality of life. However, patient inclusion criteria are heterogeneous across trials designed for older patients, and the identification of CLL-specific parameters identifying unfit patients at risk of developing drug-specific adverse events is required to guide treatment choice. Due to inclusion/exclusion criteria in trials, higher discontinuation rates with BTKi were reported in real-world studies, and registry analyses provided useful information on factors predicting earlier discontinuation in a real-world setting. Though targeted agents were shown to be cost-effective treatments in high-income countries, the out-of-pocket expenses may limit accessibility to these drugs, and the overall expenditure for new drugs in CLL is projected to increase substantially, posing an issue for sustainability. This being said, the choice of a finite-duration treatment based on venetoclax-containing regimens or treatment until progression with BTKi is today possible in high-income countries, and the therapy choice drivers are represented by coexisting medical conditions rather than age, patient expectations, logistics, and sustainability.

Unresolved questions in selection of therapies for treatment-naïve chronic lymphocytic leukemia

BACKGROUND

The treatment landscape for chronic lymphocytic leukemia (CLL) continues to undergo considerable evolution. Optimal selection of initial therapy from multiple effective options provides a major challenge for clinicians, who need to consider both disease and patient factors in conjunction with a view to sequencing available therapies in event of disease relapse.

REVIEW

We explore the most topical clinically relevant unresolved questions through discussion of important available pertinent literature and propose expert opinion based on these data. (1) Shrinking role of chemoimmunotherapy (CIT); while novel therapies are generally superior, we highlight the utility of FCR for IGHV-mutated CLL. (2) Choosing between inhibitors of Bruton's tyrosine kinase (BTKi); while efficacy between agents is likely similar there are important differences in toxicity profiles, including the incidence of cardiac arrhythmia and hypertension. (3) BTKi with or without anti-CD20 monoclonal antibodies (mAb); while obinutuzumab-acalabrutinib (AO) may confer superior progression-free survival to acalabrutinib (Acala), this is not true of rituximab (Ritux) to ibrutinib (Ib)-we highlight that potential for increased side effects should be carefully considered. (4) Continuous BTKi versus time-limited venetoclax-obinutuzumab (VenO); we propose that venetoclax (Ven)-based therapy is generally preferable to BTKi with exception of TP53 aberrant disease. (5) BTKi-Ven versus VenO as preferred time-limited therapy; we discuss comparable efficacies and the concerns about simultaneous 1L exposure to both BTKi and Ven drug classes. (6) Utility of triplet therapy (BTKi-Ven-antiCD20 mAb) versus VenO; similar rates of complete response are observed yet with greater potential for adverse events. (7) Optimal therapy for TP53 aberrant CLL; while limited data are available, there are likely effective novel therapy combinations for TP53 aberrant disease including BTKi, BTKi-Ven ± antiCD20 mAb.

CONCLUSION

Frontline therapy for CLL should be selected based on efficacy considering the patient specific biologic profile of their disease and potential toxicities, considering patient comorbidities and preferences. With the present paradigm of sequencing effective agents, 1L combinations of novel therapies should be used with caution in view of potential adverse events and theoretical resistance mechanism concerns in the absence of compelling randomized data to support augmented efficacy.

Bruton tyrosine kinase inhibitors: can they be optimized for the treatment of neuroinflammatory disorders?

INTRODUCTION

Bruton's tyrosine kinase (BTK) is a multifaceted player of the immune system which has been involved in the survival of hematological malignancies but also in the pathogenesis of immune-mediated diseases. Oral BTK inhibitors (BTKi) have become a cornerstone for the treatment of patients with B-cell malignancies, and are under investigation for several immune-mediated diseases.

AREAS COVERED

We reviewed the biology of BTK and emerging data on BTKi in patients with neuroinflammatory disorders of both the peripheral and central nervous system.

EXPERT OPINION

We support the use of BTKi in relapsed/refractory patients with multiple sclerosis and anti-MAG antibody neuropathies. However, other immune-mediated neuroinflammatory disorders are likely to benefit from BTKi. Whether BTKi will improve the response rates than conventional therapies in previously untreated patients is unknown and will be assessed within future clinical trials. Furthermore, the availability of more selective BTKi, with less adverse events, will improve patients' tolerability and expand our treatment landscape.

Mutational Profile in 75 Patients With Anti-Myelin-Associated Glycoprotein Neuropathy: Clinical and Hematologic Therapy Response and Hints on New Therapeutic Targets

BACKGROUND AND OBJECTIVES

Neuropathy with antibodies to myelin-associated glycoprotein (MAG) is the most common paraproteinemic IgM neuropathy. Recently, the mutational profile of the MYD88 and CXCR4 genes has been included in the diagnostic workup of IgM monoclonal gammopathies. The objective of our study was to assess the prevalence of MYD88 ^L265P and CXCR4 ^S338X gene variants in patients with anti-MAG antibody neuropathy. Secondary aims were to evaluate possible correlations between the mutational profile and neuropathy severity, antibody titers, and treatment response.

METHODS

Seventy-five patients (47 men, mean age at molecular analysis 70.8 ± 10.2 years; mean disease duration 5.1 ± 4.9 years) with anti-MAG antibody neuropathy were recruited. Among them, 38 (50.7%) had IgM monoclonal gammopathy of undetermined significance, 29 (38.7%) Waldenstrom macroglobulinemia (WM), and 8 (10.6%) chronic lymphocytic leukemia/marginal zone lymphoma/hairy cell leukemia variant. Molecular analysis was performed on DNA from the bone marrow mononuclear cells in 55 of 75 patients and from peripheral mononuclear cells in 18 of 75 patients. Forty-five patients were treated with rituximab, 6 with ibrutinib, 2 with obinutuzumab-chlorambucil, and 3 with venetoclax-based therapy. All the patients were assessed with the Inflammatory Neuropathy Cause and Treatment (INCAT) Disability Scale, INCAT Sensory Sum Score, and MRC Sum Score at baseline and follow-up. We considered as responders, patients who improved by at least 1 point in 2 clinical scales.

RESULTS

Fifty patients (66.7%) carried the MYD88^L265P variant, with a higher frequency in WM and naive patients (77.2% vs 33.3%, p = 0.0012). No patients harbored the CXCR4^S338X variant. There were no significant differences in hematologic data (IgM levels, M protein, and anti-MAG antibody titers), neuropathy severity, or response to rituximab in MYD88-altered and MYD88 wild-type patients. Nine of 11 (81.8%) patients treated with novel targeted drug, according to the MYD88 status, responded to treatments.

DISCUSSION

MYD88^L265P variant has a high prevalence (66.7%) in anti-MAG antibody neuropathy representing a potential effective mutational target for Bruton tyrosine kinase inhibitors. MYD88^L265P variant, however, does not seem to be a prognostic factor of neuropathy severity or response to rituximab. In patients not responding or becoming refractory to rituximab, a tailored therapy with new effective target therapies should be considered.