Monitoring and Managing BTK Inhibitor Treatment-Related Adverse Events in Clinical Practice

Real-world safety profile of zanubrutinib: a disproportionality analysis based on the FAERS database

OBJECTIVE

Zanubrutinib is a second-generation Bruton's tyrosine kinase inhibitor that has been approved for the treatment of several B cell malignancies. The aim of this study was to evaluate adverse events (AEs) associated with zanubrutinib based on the real-world data.

DESIGN

A disproportionality analysis was performed to identify the potential zanubrutinib-related AEs.

SETTING

The Food and Drug Administration AE Reporting System database from the fourth quarter of 2019 to the third quarter of 2023.

MAIN OUTCOME MEASURES

The results of the disproportionality analyses were presented as reported ORs (RORs). When the lower limit of the 95% CI for the ROR is greater than 1 and the number of AE reports is≥3, it indicates that the preferred term (PT) may be a positive AE signal.

RESULTS

A total of 846 AE reports with zanubrutinib as the primary suspect drug were obtained, with 2826 AEs. A total of 74 positive PT signals were detected across 18 system organ classes (SOCs). The most significant signal for SOC was 'blood and lymphatic system disorders' (ROR=2.8, 95% CI 2.3 to 3.3), while the most significant signal for PT was 'haemorrhage subcutaneous' (ROR=190.8, 95% CI 128.0 to 284.5). 13 unexpected off-label AEs were also observed, such as abnormal hair texture, skin discolouration, hypernatraemia, pericardial effusion and hypersomnia. The median time to onset of AEs associated with zanubrutinib was 51 days (IQR 13-192 days) and was consistent with the early failure model. In comparison with zanubrutinib monotherapy, the combination of zanubrutinib and rituximab therapy was linked to a higher risk of specific AEs, including myelosuppression, pneumonia, leucopenia, thrombocytopenia, abdominal pain, anaemia, pancytopenia and respiratory failure. Furthermore, the combination of zanubrutinib and chemotherapy increased the risk of several severe AEs, such as cardiac arrest, elevated blood lactate dehydrogenase levels and pancytopenia.

CONCLUSIONS

The results of the analysis provided valuable insights into the safety profile of zanubrutinib-treated patients, which was helpful for clinical monitoring and identifying potential AEs related to zanubrutinib.

BTK inhibitors: moving the needle on the treatment of chronic lymphocytic leukemia

INTRODUCTION

Bruton's tyrosine kinaseinhibitors (BTKis) changed the trajectory of upfront and relapsed/refractory chronic lymphocytic leukemia (CLL) treatment. However, BTKis are plagued by a spectrum of toxicities. Zanubrutinib was developed to circumvent challenges with prolonged tolerability by increasing BTK selectivity and maximizing efficacy through pharmacokinetic/pharmacodynamic optimization. However, with the availability of ibrutinib, acalabrutinib, and zanubrutinib, limited data exists to guide sequencing of BTKi therapy in the relapsed/refractory setting.

AREAS COVERED

We review the first head-to-head trial (ALPINE) of zanubrutinib versus ibrutinib for the treatment of relapsed/refractory CLL and compare zanubrutinib's clinical efficacy and toxicities, including in patients with del(17p) and/or TP53 mutations to ibrutinib and acalabrutinib.

EXPERT OPINION

Zanubrutinibrepresents one of the new standards of care for relapsed/refractory CLL based on superior progression-free survival and response rates over ibrutinib. Whilezanubrutinib is associated with fewer cardiac toxicities, similar rates of neutropenia and hypertension are noted. Ongoing studies are pushing the envelope, utilizing targeted drug combinations and minimal residual disease markers as well as receptor tyrosine kinase-like orphan receptor 1 inhibitors, chimeric antigen receptor T-cells, and novel BTK degraders. However, zanubrutinibrepresents a strong contender in the arsenal of treatment options for relapsed/refractory CLL.

Pharmacological management of chronic lymphocytic leukemia: current and emerging therapies

INTRODUCTION

Chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL), characterized by its monoclonal lymphoproliferative nature, is an indolent but incurable malignancy. The treatment landscape of CLL/SLL has drastically transformed in the last decade since the introduction of targeted therapy and immune-effector T-cell therapy. The paradigm shift from chemoimmunotherapy to targeted and cellular therapies was largely driven by improved efficacy and safety. With the success of targeted therapies, novel agents and combinations are rapidly emerging on the horizon.

AREAS COVERED

In this review, we will summarize clinical evidence supporting current and emerging therapies with emphasis on investigational therapies and novel combinations of commercial agents. Clinical trials were identified via clinicaltrials.gov, and a PubMed literature search was last performed in June 2024.

EXPERT OPINION

With the availability of more effective and better-tolerated treatments for CLL/SLL, the role of early intervention should be further investigated due to its potential to alter disease course, delay progression, and improve overall survival rates. With many highly effective agents and combinations expected to become commercially available, attention to safety profiles and careful selection of patients for each treatment will be critical, with consideration of comorbidities, logistical issues, and financial burden of treatment.

Real-world patterns and sequences of targeted therapy use in chronic lymphocytic leukemia and small lymphocytic lymphoma in the United States: a longitudinal study

With increasing focus on novel targeted therapies for chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), this longitudinal claims-based study evaluated real-world CLL/SLL treatment sequences, particularly sequential targeted therapy. Among patients with first-line (1 L) treatment in 2014-2017 (N = 2,612; median follow-up = 3 years), the most common 1 L treatment was chemoimmunotherapy (CIT; 44.6%), followed by CD20 (25.2%) and Bruton's tyrosine kinase inhibitors (BTKi; 21.7%). Among those with 1 L in 2018-2021 (N = 4,534; median follow-up = 1 year), these were BTKi (45.5%), CD20 (20.4%), CIT (17.5%), and B-cell lymphoma 2 inhibitor (8.3%). In 2014-2017, the proportion of patients receiving sequential targeted therapy in the first 2 LOTs was 11.2% (80.2% was BTKi→BTKi); in 2018-2021, this proportion was 34.3% (66.4% was BTKi→BTKi). Over time, there was a substantial increase in targeted therapy use in 1 L and sequential targeted therapy, particularly with BTKi→BTKi. Future studies should assess clinical outcomes to determine optimal sequences for CLL/SLL and reasons for restarting BTKi.

Bruton's tyrosine kinase (BTK) inhibitors for the treatment of primary central nervous system lymphoma (PCNSL): current progress and latest advances

The incidence of primary central nervous system lymphoma (PCNSL) has steadily increased, particularly in elderly patients. Although highly responsive to first-line chemotherapy and radiotherapy, approximately 50% of patients relapse or become refractory within 1 year. Prognosis following relapse is dismal and no standard salvage therapy exists. Bruton's tyrosine kinase (BTK), a key regulator of the B-cell receptor (BCR) pathway, has emerged as a promising therapeutic target. The first BTK inhibitor ibrutinib has been evaluated in the relapsed/refractory PCNSL setting, with overall response rates of 51.9%-89.0% and median progression-free survival of 4.6-4.8 months. However, ibrutinib inhibits several kinases in addition to BTK, leading to off-target effects. Second-generation BTK inhibitors have since been developed, which afford greater selectivity for BTK and fewer off-target effects. We review current practices in the diagnosis and evaluation of PCNSL, as well as clinical trials of BTK inhibitors in PCNSL and future developments in PCNSL treatment.

Evidence-based expert consensus on clinical management of safety of Bruton's tyrosine kinase inhibitors (2024)

Bruton's tyrosine kinase inhibitors (BTKis) have revolutionized the treatment of B-cell lymphomas. However, safety issues related to the use of BTKis may hinder treatment continuity and further affect clinical efficacy. A comprehensive and systematic expert consensus from a pharmacological perspective is lacking for safety issues associated with BTKi treatment. A multidisciplinary consensus working group was established, comprising 35 members from the fields of hematology, cardiovascular disease, cardio-oncology, clinical pharmacy, and evidence-based medicine. This evidence-based expert consensus was formulated using an evidence-based approach and the Delphi method. The Joanna Briggs Institute Critical Appraisal (JBI) tool and Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach were used to rate the quality of evidence and grade the strength of recommendations, respectively. This consensus provides practical recommendations for BTKis medication based on nine aspects within three domains, including the management of common adverse drug events such as bleeding, cardiovascular events, and hematological toxicity, as well as the management of drug-drug interactions and guidance for special populations. This multidisciplinary expert consensus could contribute to promoting a multi-dimensional, comprehensive and standardized management of BTKis.

Updates of primary central nervous system lymphoma

Lymphoma occurring in the central nervous system is considered primary central nervous system lymphoma (PCNSL), usually without systematic lesions. Over the last few decades, a deep understanding of PCNSL has been lacking due to the low incidence rate, and the overall survival and progression-free survival of patients with PCNSL are lower than those with other types of non-Hodgkin lymphoma. Recently, there have been several advancements in research on PCNSL. Advances in diagnosis of the disease are primarily reflected in the promising diagnostic efficiency of novel biomarkers. Pathogenesis mainly involves abnormal activation of nuclear factor kappa-B signaling pathways, copy number variations, and DNA methylation. Novel therapies such as Bruton's tyrosine kinase inhibitors, immunomodulatory drugs, immune checkpoint inhibitors, and phosphoinositide 3-kinase/mammalian target of rapamycin inhibitors are being evaluated as possible treatment options for PCNSL, especially for relapsed/refractory (R/R) cases. Several clinical trials also indicated the promising feasibility and efficacy of chimeric antigen receptor T-cell therapy for selected R/R PCNSL patients. This review focuses on discussing recent updates, including the diagnosis, pathogenesis, and novel therapy of PCNSL.

The Safety of Novel Therapies in Chronic Lymphocytic Leukemia in the Era of Intermittent Fasting: A Pharmacology-Based Review

Intermittent fasting (IF) has recently gained popularity due to its emerging benefits in reducing weight and improving metabolic health. Concurrently, novel agents (NAs) like venetoclax and Bruton tyrosine kinase inhibitors (BTKIs) have revolutionized the treatment of chronic lymphocytic leukemia (CLL). Unfortunately, it is unclear whether the associated risks of tumor lysis syndrome (TLS) and gastrointestinal bleeding (GIB) are increased in IF practitioners receiving NAs. This review explored the literature available on the permissibility of IF in CLL patients undergoing treatment with first-line NAs (FLNAs). Literature was scoped to identify IF patterns and the available data on TLS and GIB risks associated with food and fluid intake in CLL patients receiving FLNAs. Although current evidence is insufficient to recommend IF in this population, it may be possible for patients on venetoclax to conservatively practice fluid-liberal IF, provided that adequate hydration and the consistent administration of food are achieved. In contrast, considering the significant risk of TLS and the pharmacokinetics of venetoclax, patients should be discouraged from practicing fluid-restricted IF, especially during the ramp-up phase. Moreover, patients on BTKIs ought to refrain from IF due to the possible risk of GIB until further data are available. Further research is needed to provide conclusive recommendations.

Cardiovascular events reported in patients with B-cell malignancies treated with zanubrutinib

ABSTRACT

First-generation Bruton tyrosine kinase (BTK) inhibitor, ibrutinib, has been associated with an increased risk of cardiovascular toxicities. Zanubrutinib is a more selective, next-generation BTK inhibitor. In this analysis, incidence rates of atrial fibrillation, symptomatic (grade ≥2) ventricular arrhythmia, and hypertension were evaluated in a pooled analysis of 10 clinical studies with zanubrutinib monotherapy in patients (N = 1550) with B-cell malignancies and a pooled analysis of head-to-head studies comparing zanubrutinib with ibrutinib (ASPEN cohort 1; ALPINE). Among the 10 studies, most patients (median age, 67 years) were male (66.3%) and had CLL/SLL (60.5%). Overall incidence and exposure-adjusted incidence rates (EAIR) for atrial fibrillation, symptomatic ventricular arrhythmia, and hypertension were lower with zanubrutinib than ibrutinib. Despite a similar prevalence of preexisting cardiovascular events in ASPEN and ALPINE, atrial fibrillation/flutter incidence rates (6.1% vs 15.6%) and EAIR (0.2 vs 0.64 persons per 100 person-months; P < .0001) were lower with zanubrutinib than with ibrutinib. Symptomatic ventricular arrhythmia incidence was low for both zanubrutinib (0.7%) and ibrutinib (1.7%) with numerically lower EAIR (0.02 vs 0.06 persons per 100 person-months, respectively) for zanubrutinib. The hypertension EAIR was lower with zanubrutinib than ibrutinib in ASPEN but similar between treatment arms in ALPINE. The higher hypertension EAIR in ALPINE was inconsistent with other zanubrutinib studies. However, fewer discontinuations (1 vs 14) and deaths (0 vs 6) due to cardiac disorders occurred with zanubrutinib versus ibrutinib in ALPINE. These data support zanubrutinib as a treatment option with improved cardiovascular tolerability compared with ibrutinib for patients with B-cell malignancies in need of BTK inhibitors. These trials were registered at www.ClinicalTrials.gov as # NCT03053440, NCT03336333, NCT03734016, NCT04170283, NCT03206918, NCT03206970, NCT03332173, NCT03846427, NCT02343120, and NCT03189524.

Chronic Lymphocytic Leukemia: Management of Adverse Events in the Era of Targeted Agents

The treatment landscape for CLL has undergone a profound transformation with the advent of targeted agents (TAs) like Bruton's Tyrosine Kinase inhibitors (BTKis) and BCL-2 inhibitors (BCL-2is). These agents target crucial cellular pathways in CLL, offering superior efficacy over traditional chemo-immunotherapy, which has led to improved progression-free and overall survival rates. This advancement promises enhanced disease control and potentially normal life expectancy for many patients. However, the journey is not without challenges, as these TAs are associated with a range of adverse events (AEs) that can impact treatment efficacy and patient quality of life. This review focuses on detailing the various AEs related to TA management in CLL, evaluating their frequency and clinical impact. The aim is to present a comprehensive guide to the effective management of these AEs, ensuring optimal tolerability and efficacy of TAs. By reviewing the existing literature and consolidating findings, we provide insights into AE management, which is crucial for maximizing patient outcomes in CLL therapy.

BTK inhibitors in CLL: second-generation drugs and beyond

ABSTRACT

BTK inhibitors (BTKis) are established standards of care in multiple B-cell malignancies including chronic lymphocytic leukemia, mantle cell lymphoma, and Waldenstrom macroglobulinemia. The first-generation BTKi ibrutinib demonstrated superiority over standard chemoimmunotherapy regimens in multiple randomized trials but is limited by cardiovascular side effects such as atrial fibrillation and hypertension. Second-generation BTKis have improved selectivity and demonstrate reduced rates of cardiovascular complications in 3 head-to-head ibrutinib studies. The emergence of BTK C481S mutation has led to the development of noncovalent, "reversible" BTKis, such as pirtobrutinib, which are agnostic to the C481S mutation. However, these inhibitors are associated with resistant mutations outside the C481 hot spot. These variant non-C481 mutations are of great clinical interest because some are shared among pirtobrutinib, zanubrutinib, and acalabrutinib, with potential implications for cross resistance and treatment sequencing. Finally, BTK protein degraders with in vitro activity against C481 and non-C481 mutations are currently in clinical development. Here, we review the evolution of therapeutic BTK-targeting and discuss future directions for clinical research.

A real-world pharmacovigilance study of FDA Adverse Event Reporting System (FAERS) events for Bruton's tyrosine kinase inhibitors (BTKis) single and its combination therapy

BACKGROUND

Bruton's tyrosine kinase inhibitors (BTKis) are targeted treatments for B-cell tumors but have significant side effects. This study assesses and contrasts the side effects of BTKis alone and its four combination therapies.

RESEARCH DESIGN AND METHODS

The reporting odds ratio (ROR) was used to analyze the data on three BTKis monotherapies and combinations of ibrutinib with rituximab, obinutuzumab, venetoclax, and lenalidomide in the FDA Adverse Event Reporting System (FAERS) database up to December 2022.

RESULTS

We analyzed the top 20 PTs for each treatment regimen. In monotherapies, atrial fibrillation (ROR (95% CI): 9.88 (9.47-10.32)) in zanubrutinib and rash (6.97 (5.42-8.98)) in acalabrutinib had higher associations. In combinations, infection (6.86 (6.11-7.70)), atrial fibrillation (27.96 (22.61-34.58)) and myelosuppression (10.09 (8.89-11.46)) were vital signals when ibrutinib was combined with obinutuzumab, and pyrexia (4.22 (2.57-6.93)) had a high signal value when combined with lenalidomide. Hemorrhage had a lower signal value when combined with venetoclax compared to ibrutinib alone (2.50 (2.18-2.87) vs 3.60 (3.52-3.68)).

CONCLUSIONS

The ibrutinib-obinutuzumab combo has the highest risk of infection, atrial fibrillation, and myelosuppression, and the ibrutinib-lenalidomide combo has the highest risk of pyrexia. However, the ibrutinib-venetoclax combo has a lower risk of hemorrhage than monotherapy.

Investigating bleeding adverse events associated with BTK inhibitors in the food and drug administration adverse event reporting system (FAERS)

BACKGROUND

This study analyzed the bleeding adverse events (AEs) resulting from the treatment of B-cell lymphoma with Bruton tyrosine kinase (BTK) inhibitors, according to reports in the US Food and Drug Administration's Adverse Event Reporting System (FAERS).

METHODS

Bleeding AEs associated with BTK inhibitors (including ibrutinib, zanubrutinib, and acalabrutinib) from the first quarter of 2013 to the third quarter of 2023 were extracted. Reporting odds ratio (ROR) and proportional reporting ratio (PRR) were reported. Preferred Terms (PTs) of Medical Dictionary for Regulatory Activities (MedDRA) terms were mapped to System Organ Class terms (SOC) terms and analyzed bleeding AEs associated with three BTK inhibitors.

RESULTS

A total of 463 cases of bleeding AEs were included. Contusion, subcutaneous hemorrhage, hematuria, and cerebral hemorrhage were included in PTs. Blood urine was present and subdural hematoma were also reported. The incidence of bleeding AEs was higher with ibrutinib (Case number = 10,696) than with zanubrutinib (Case number = 213) and acalabrutinib (Case number = 314).

CONCLUSION

Our findings indicate that bleeding AEs linked to BTK inhibitors in various conditions underscore the need for cautious clinical decision-making, particularly in nervous system disorders, injuries, poisoning, surgical complications, vascular disorders, and others.

Integrated Safety Analysis of Ritlecitinib, an Oral JAK3/TEC Family Kinase Inhibitor, for the Treatment of Alopecia Areata from the ALLEGRO Clinical Trial Program

BACKGROUND

The ALLEGRO phase 2a and 2b/3 studies demonstrated that ritlecitinib, an oral JAK3/TEC family kinase inhibitor, is efficacious at doses of ≥ 30 mg in patients aged ≥ 12 years with alopecia areata (AA).

OBJECTIVE

The objective of this study was to evaluate the safety of ritlecitinib in an integrated analysis of four studies in AA.

METHODS

Two cohorts were analyzed: a placebo-controlled and an all-exposure cohort. Proportions and study size-adjusted incidence rates (IRs) of adverse events (AEs) of interest and laboratory abnormalities are reported.

RESULTS

In the placebo-controlled cohort (n = 881; median exposure: 169 days), the proportion of ritlecitinib-treated patients with AEs was 70.2-75.4% across doses versus 69.5% in the placebo group; serious AEs occurred in 0-3.2% versus 1.9% for the placebo. A total of 19 patients permanently discontinued due to AEs (5 while receiving the placebo). In the all-exposure cohort (n = 1294), median ritlecitinib exposure was 624 days [2091.7 total patient-years (PY)]. AEs were reported in 1094 patients (84.5%) and serious AEs in 57 (4.4%); 78 (6.0%) permanently discontinued due to AEs. The most common AEs were headache (17.7%; 11.9/100 PY), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) positive test (15.5%; 9.8/100 PY), and nasopharyngitis (12.4%; 8.2/100 PY). There were two deaths (breast cancer and acute respiratory failure/cardiorespiratory arrest). Proportions (IRs) were < 0.1% (0.05/100 PY) for opportunistic infections, 1.5% (0.9/100 PY) for herpes zoster, 0.5% (0.3/100 PY) for malignancies (excluding nonmelanoma skin cancer), and 0.2% (0.1/100 PY) for major adverse cardiovascular events.

CONCLUSIONS

Ritlecitinib is well tolerated with an acceptable safety profile up to 24 months in patients aged ≥ 12 years with AA (video abstract and graphical plain language summary available).

TRIAL REGISTRIES

ClinicalTrials.gov: NCT02974868 (date of registration: 11/29/2016), NCT04517864 (08/18/2020), NCT03732807 (11/07/2018), and NCT04006457 (07/05/2019).

Urinary tract infection following the use of BTK inhibitors: a real-world analysis of post-marketing surveillance data

BACKGROUND

Emerging case reports have raised awareness of urinary tract infection (UTI) which maybe a potentially serious complication. The present study aimed to summarize the clinical characteristics of patients with BTK inhibitor-related UTI, and the association between BTK inhibitors and UTI events was also assessed by disproportionality analysis.

RESEARCH DESIGN AND METHODS

We conducted an observational, retrospective, and pharmacovigilance study using data from the Food and Drug Administration Adverse Event Reporting System (FAERS) database. Data were retrieved from Quarter 1, 2004 to Quarter 2, 2022. The clinical characteristics of cases were summarized using descriptive statistics. We used the χ2 or Fisher exact methods for the analysis of categorical variables and the Mann-Whitney test or Student's t-text for the comparisons of continuous variables between fatal and non-fatal cases. A p-value less than 0.05 is considered to be statistically significant. Information component (IC) and reporting odds ratio (ROR) were used to evaluate the association.

RESULTS

BTK inhibitors were identified as the suspected drug causing UTI in 539 cases. The age of those cases concentrated on 60-89 years (87.83%, data available in 263/539). UTI signals were detected during BTK inhibitors treatment (IC 0.95[0.83-1.08], ROR 1.96[1.80-2.13]). The association between BTK inhibitors and UTI events was shown among all groups but not in the group of age<60 years old. There were no significant differences in age and gender between fatal and non-fatal cases. However, a significant difference in reporting regions was found (p = 0.016), with the highest percentage of reported deaths occurring in Europe (26.15%, p = 0.000).

CONCLUSIONS

Our study suggested a safety signal for UTI and BTK inhibitors compared to all other drugs in the database, especially in the elder (age ≥60). Further studies are needed to clarify these results.

Time to next treatment in patients with chronic lymphocytic leukemia initiating first-line ibrutinib or acalabrutinib

Aim: To investigate real-world time to next treatment in patients with chronic lymphocytic leukemia initiating first-line (1L) ibrutinib or acalabrutinib. Materials & methods: US specialty pharmacy electronic medical records (21/11/2018-30/4/2022) were used; patients initiated 1L on/after 21/11/2019 (acalabrutinib approval). Results: Among 710 patients receiving ibrutinib, 5.9% initiated next treatment (mean time to initiation = 9.2 months); among 373 patients receiving acalabrutinib, 7.5% initiated next treatment (mean time to initiation = 5.9 months). Adjusting for baseline characteristics, acalabrutinib-treated patients were 89% more likely to initiate next treatment (hazard ratio = 1.89; p = 0.016). Conclusion: This study addresses a need for real-world comparative effectiveness between 1L ibrutinib and acalabrutinib and shows that next treatment (a clinically meaningful measure for real-world progression) occurred less frequently with 1L ibrutinib.

Chinese expert consensus on Bruton tyrosine kinase inhibitors in the treatment of B-cell malignancies

Targeted therapy with Bruton tyrosine kinase (BTK) inhibitors have revolutionized the treatment of patients with various B-cell malignancies. BTK inhibitors such as ibrutinib, zanubrutinib, orelabrutinib, and acalabrutinib have shown good clinical efficacy and better safety profiles than those of traditional chemotherapy and chemoimmunotherapy regimens. Multiple studies on new BTK inhibitors are ongoing, which may provide more therapeutic options for the treatment of B-cell malignancies. Considering the unmet need of evidence on BTK inhibitors in all clinical settings and to standardize the use of BTK inhibitors available in mainland China, Taiwan, Hong Kong, and Macau regions, this consensus has been formulated for the treatment of various B-cell malignancies based on the clinical practice and available evidences on the use of BTK inhibitors. The recommendations of this consensus will provide guidance to physicians and clinical researchers on the effective treatment of B-cell malignancies with BTK inhibitors.

A prediction model for severe hematological toxicity of BTK inhibitors

Bruton's tyrosine kinase inhibitor (BTKi) has revolutionized the treatment of B-cell lymphomas. However, BTKi-related hematological toxicity hinders treatment continuity and may further affect clinical efficacy. To identify risk factors and predict the likelihood of BTKi-related hematological toxicities, we constructed and validated a prediction model for severe hematological toxicity of BTKi. Approved by the hospital medical science research ethics committee (No. M2022427), we collected real-world data in patients treated with BTKi from a Lymphoma Research Center in China. The outcome of interest was severe hematological toxicity caused by BTKi. 36 candidate variables were categorized into demographics, diagnostic and treatment information, laboratory data, and medical history. The study sample was randomly divided into training (70%) and validation (30%) sets. We developed and compared the performance of various modelling methods, including decision tree (DT), random forest (RF), gradient boosting decision tree (GBDT), extreme gradient boosting (XGBoost), light gradient boosting machine (LightGBM), and logistic regression (LR). Finally, we constructed a Web-calculator of the optimal model to estimate the risk of hematological toxicity. This study was designed, conducted and reported strictly in compliance with the TRIPOD checklist. Data from a total 121 patients were included [median age, 65 years (range, 56-73 years); 74 (61.15%) men; 47 (38.84%) severe hematological toxicity]. The XGBoost model demonstrated better overall properties than other models, achieving high discrimination (AUC: 0.671; accuracy: 0.730; specificity: 0.913) and clinical benefit. The following 10 variables were used to develop the XGBoost model: white blood cell count (WBC), neutrophil count (Neut), red blood cell count (RBC), platelet count (PLT), fibrinogen (Fib), total protein (TP), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), gender and type of BTKi. SHAP values demonstrated insightful associations between these variables and hematological toxicity. Finally, to facilitate clinical and research use, we also deploy the XGBoost model on a web-calculator for free access. The XGBoost model with promising accuracy was developed to predict the severe hematological toxicity of BTKi. It helps to strengthen the proactive monitoring and management of patients with hematological toxicity, and thus achieve long-term continuous BTKi treatment.

Zanubrutinib: past, present, and future

In recent years, Bruton tyrosine kinase (BTK) inhibitors have provided significant advances in the treatment of patients with B-cell malignancies. Ibrutinib was the first BTK inhibitor to be approved, and it changed the standard-of-care treatment for diseases such as chronic lymphocytic leukemia, mantle cell lymphoma, marginal zone lymphoma, and Waldenström macroglobulinemia, improving efficacy outcomes and safety compared to chemotherapy. In this article, we review the development of zanubrutinib, a next-generation BTK inhibitor, from molecular design to patient-related outcomes. We start this journey by providing insights into the discovery of BTK and the physiologic, genetic, and molecular characterization of patients lacking this kinase, together with the brief treatment landscape in the era of chemo-immunotherapies. Zanubrutinib was originally developed by applying a structure-activity strategy to enhance the specificity as well as enzymatic and pharmacokinetic properties. Preclinical studies confirmed greater specificity and better bioavailability of zanubrutinib compared with that of ibrutinib, which supported the initiation of clinical trials in humans. Preliminary clinical results indicated activity in B-cell malignancies together with an improved safety profile, in line with less off-target effects described in the preclinical studies. The clinical program of zanubrutinib has since expanded significantly, with ongoing studies in a wide range of hemato-oncological diseases and in combination with many other therapies. Zanubrutinib currently is approved for various B-cell malignancies in multiple countries. This story highlights the importance of multidisciplinary collaborative research, from bench to bedside, and provides an example of how the commitment to finding improved treatment options should always run parallel to patient care.

A fixed-duration immunochemotherapy approach in CLL: 5.5-year results from the phase 2 ICLL-07 FILO trial

In previously untreated, medically fit patients with chronic lymphocytic leukemia (CLL), research is focused on developing fixed-duration strategies to improve long-term outcomes while sparing patients from serious toxicities. The ICLL-07 trial evaluated a fixed-duration (15-month) immunochemotherapy approach in which after obinutuzumab-ibrutinib induction for 9 months, patients (n = 10) in complete remission (CR) with bone marrow (BM) measurable residual disease (MRD) <0.01% continued only ibrutinib 420 mg/day for 6 additional months (I arm), whereas the majority (n = 115) received up to 4 cycles of fludarabine/cyclophosphamide-obinutuzumab 1000 mg alongside the ibrutinib (I-FCG arm). Primary analysis at month 16 showed that 84 of 135 (62.2%) patients enrolled achieved CR with a BM MRD <0.01%. Here, we report follow-up at median 63 months. Peripheral blood (PB) MRD was assessed 6 monthly beyond the end of treatment using a highly sensitive (10-6) flow cytometry technique. In the I-FCG arm, the PB MRD <0.01% rate (low-level positive <0.01% or undetectable with limit of detection ≤10-4) in evaluable patients was still 92.5% (74/80) at month 40 and 80.6% (50/62) at month 64. No differences in the PB MRD status were apparent per to the IGHV mutational status. In the overall population, 4-year progression-free and overall survival rates were 95.5% and 96.2%, respectively. Twelve deaths occurred overall. Fourteen serious adverse events occurred beyond the end of treatment. Thus, our fixed-duration immunochemotherapy approach produced deep and sustained PB MRD responses, high survival rates, and low long-term toxicity. A randomized trial is needed to compare our immunochemotherapy approach with a chemotherapy-free strategy. This trial was registered at www.clinicaltrials.gov as #NCT02666898.

Predictors of ibrutinib-associated atrial fibrillation: 5-year follow-up of a prospective study

Ibrutinib-associated atrial fibrillation (IRAF) emerged among the adverse events of major interests in ibrutinib-treated patients as real-world studies showed a higher incidence compared to clinical trials. We prospectively analyzed predictors of IRAF in 43 single-center consecutive patients affected by chronic lymphocytic leukemia that started therapy with ibrutinib between 2015 and 2017. Key secondary endpoints were to describe the management of IRAF and survival outcomes. During a median follow-up period of 52 months, we registered 45 CV events, with a total of 23 AF events in 13 patients (CI 30.0% (95% CI: 16.5-43.9)). Pre-existent cardiovascular risk factors, in particular hypertension, a previous history of AF and a high Shanafelt risk score emerged as predictors of IRAF. Baseline echocardiographic evaluation of left atrial (LA) dimensions confirmed to predict IRAF occurrence and cut-off values were identified in our cohort: 32 mm for LA diameter and 18 cm2 for LA area. No difference in progression free survival and overall survival emerged in patients experiencing IRAF. Following AF, anticoagulation was started in all eligible patients, and cardioactive therapy was accordingly modified. Echocardiography represents a highly reproducible and widespread tool to be included in the work-up of ibrutinib candidates; the identification of IRAF predictors represents a useful guide to clinical practice.

Health resource utilization and costs of care for adult patients with relapsed or refractory mantle cell lymphoma in the United States: a retrospective claims analysis

OBJECTIVES

We assessed real-world healthcare resource utilization (HRU) and costs among US patients with relapsed or refractory mantle cell lymphoma (R/R MCL) by line of therapy (LoT).

METHODS

We selected patients from MarketScan® (1/1/2016-12/31/2020): ≥1 claims of MCL-indicated first line (1L) therapies, ≥1 diagnoses of MCL pre-index date (1L initiation date), ≥6-month continuous enrollment pre-index date, second line (2L) therapy initiation, ≥18 years old at 2L, and no clinical trial enrollment. Outcomes included time to next treatment (TTNT), all-cause HRU, and costs.

RESULTS

The cohort (N = 142) was 77.5% male, aged 62 years (median). Sixty-six percent and 23% advanced to 3L and 4L+, respectively. Mean (median) TTNT was 9.7 (5.9), 9.3 (5.0), and 6.3 (4.2) months for 2L, 3L, and 4L+, respectively. Mean (median) per patient per month (PPPM) costs were $29,999 ($21,313), $29,352 ($20,033), and $30,633 ($23,662) for 2L, 3L, and 4L+, respectively. Among those who received Bruton tyrosine kinase inhibitors, mean (median) PPPM costs were $24,702 ($17,203), $31,801 ($20,363), and $36,710 ($25,899) for 2L, 3L, and 4L+, respectively.

CONCLUSIONS

During the period ending in 2020, patients relapsed frequently, incurring high HRU and costs across LoTs. More effective treatments with long-lasting remissions in R/R MCL may reduce healthcare burden.

Impact of atrial fibrillation in onco-hematological patients in Europe: a targeted literature review

INTRODUCTION

Atrial fibrillation (AF) is a common complication in cancer patients, and the increased risk associated with certain therapies poses a major challenge. The objective was to determine the clinical and economic burden of AF in onco-hematological patients in Europe.

AREAS COVERED

A targeted literature review was completed for observational, retrospective and case studies, and reviews on AF in onco-hematology published between January 2010 and 2022 in PubMed, Science Direct, Medes and IBECS. The search was based on epidemiology, cost, health-related quality of life (HRQoL), disease burden and management, and patient journey. Thirty-one studies fulfilled eligibility criteria. Annual incidence of AF during treatment varies up to 25%, and increased with first-generation Bruton tyrosine kinase inhibitors (BTKi). Risk factors include age ≥65, prior AF or hypertension, hyperlipidemia and ibrutinib use. Complications are managed with anticoagulants and/or antiarrhythmics, and regular monitoring. When AF is no longer controllable, dose reduction or discontinuation is recommended. No data on costs, HRQoL and patient journey were identified.

EXPERT OPINION

There is scarce and heterogeneous information on AF in onco-hematology in Europe. Available evidence reports a higher risk of AF associated with first-generation BTKi. Further studies are needed to understand the burden of AF in these patients.

The preclinical discovery and development of orelabrutinib as a novel treatment option for B-cell lymphoid malignancies

INTRODUCTION

Bruton's tyrosine kinase (BTK) inhibitors have recently been approved for clinical use against several B-cell indolent lymphoid malignancies, both as single agents or in combination. One second-generation BTK inhibitor that is being developed for the treatment of B-cell hematological malignancies, as well as for autoimmune disorders, is orelabrutinib.

AREAS COVERED

This paper reviews recent developments in the use of orelabrutinib against B-cell indolent lymphoid malignancies such as chronic lymphocytic leukemia, mantle cell lymphoma, diffuse large B-cell lymphoma, Waldenstrom macroglobulinemia and central nervous system lymphoma. Google Scholar and PubMed were initially searched for articles, and the corpus of articles was broadened by reviewing the references of the identified papers. All were in English. The corpus comprised papers from 2016 to April 2023. In addition, a manual search was performed of conference proceedings from the last five years of The American Society of Hematology, American Society of Clinical Oncology and the European Hematology Association.

EXPERT OPINION

Orelabrutinib is an active drug in indolent and aggressive B-cell lymphoid malignancies. It demonstrates high selectivity, good efficacy and an excellent safety profile. Nevertheless, further clinical trials are required to optimize its use. In addition, several other highly selective BTK inhibitors are being examined in early-phase studies.

Design and Characterization of a Novel Venetoclax-Zanubrutinib Nano-Combination for Enhancing Leukemic Cell Uptake and Long-Acting Plasma Exposure

Leukemia remains incurable partly due to difficulties in reaching and maintaining therapeutic drug concentrations in the target tissues and cells. Next-generation drugs targeted to multiple cell checkpoints, including the orally active venetoclax (Bcl-2 target) and zanubrutinib (BTK target), are effective and have improved safety and tolerability compared to conventional, nontargeted chemotherapies. However, dosing with a single agent frequently leads to drug resistance; asynchronous coverage due to the peak-and-trough time-course of two or more oral drugs has prevented drug combinations from simultaneously knocking out the respective drugs' targets for sustained leukemia suppression. Higher doses of the drugs may potentially overcome asynchronous drug exposure in leukemic cells by saturating target occupancy, but higher doses often cause dose-limiting toxicities. To synchronize multiple drug target knockout, we have developed and characterized a drug combination nanoparticle (DcNP), which enables the transformation of two short-acting, orally active leukemic drugs, venetoclax and zanubrutinib, into long-acting nanoformulations (VZ-DCNPs). VZ-DCNPs exhibit synchronized and enhanced cell uptake and plasma exposure of both venetoclax and zanubrutinib. Both drugs are stabilized by lipid excipients to produce the VZ-DcNP nanoparticulate (d ~ 40 nm) product in suspension. The VZ-DcNP formulation has enhanced uptake of the two drugs (VZ) in immortalized leukemic cells (HL-60), threefold over that of its free drug counterpart. Additionally, drug-target selectivity of VZ was noted with MOLT-4 and K562 cells that overexpress each target. When given subcutaneously to mice, the half-lives of venetoclax and zanubrutinib were extended by approximately 43- and 5-fold, respectively, compared to an equivalent free VZ. Collectively, these data suggest that VZ in VZ-DcNP warrant consideration for preclinical and clinical development as a synchronized and long-acting drug-combination for the treatment of leukemia.

Co-Occurring X-Linked Agammaglobulinemia and X-Linked Chronic Granulomatous Disease: Two Isolated Pathogenic Variants in One Patient

We present a unique and unusual case of a male patient diagnosed with two coexisting and typically unassociated X-linked conditions: he was initially diagnosed with X-linked agammaglobulinemia (XLA) followed by a diagnosis of X-linked chronic granulomatous disease (XCGD) and an as of yet unpublished hypomorphic gp91phox variant in the CYBB gene. The latter was tested after the finding of granulomatous gingivitis. Hematopoietic stem cell transplant (HSCT) was performed due to severe colitis and nodular regenerative hyperplasia (NRH) of the liver. Following transplant, complete donor engraftment was observed with the restoration of a normal oxidative burst and full restoration of normal levels of circulating, mature CD19+ B cells. This case is singular in that it does not involve a contiguous gene syndrome in which deleted genes are in close proximity to either BTK and CYBB, which has been previously reported. To our knowledge, this is the first reported case of XLA and XCGD co-existing in a single patient and of having both inborn errors of immunity successfully treated by HSCT.

Ibrutinib-Induced Paronychia and Periungual Pyogenic Granuloma

Nail changes elicited by Ibrutinib are relatively infrequent but are reported in the literature. Herein, we report on two cases that developed Ibrutinib-induced nail toxicities. A 63-year-old female, with relapsing mantle cell lymphoma on Ibrutinib 560mg/day for seven months developed paronychia, onychomadesis, Beau's lines, nail fragility, and brittleness over fingernails and toenails. On the other hand, an 80-year-old male with chronic lymphoid leukemia developed a bloody papule with hemorrhagic crust and nail-plate abnormalities. Skin toxicities manifested eight months after initiating Ibrutinib therapy. From a clinical perspective, Ibrutinib-induced chronic paronychia and PG have been established. All other PG triggers have been ruled out. After the cessation of Ibrutinib, the PG improved for both cases. The exact pathogenesis of PG induced by Ibrutinib is not yet understood but it had been compared to retinoid-related changes. Thus, further research and reporting of similar cases should be done to further understand the pathophysiology of such manifestations.

Management of front line chronic lymphocytic leukemia

Treatment options with targeted agents have changed the treatment landscape of CLL profoundly. Besides chemoimmunotherapy, treatment regimen approved for frontline therapy include continuous treatment with BTK inhibitors like ibrutinib and acalabrutinib or fixed-duration regimen like venetoclax-obinutuzumab with the approval of venetoclax-ibrutinib to be awaited. Although these agents have usually manageable side effects, toxicities might limit choices for the individual patient. We here discuss latest trial data and propose a treatment algorithm for frontline treatment of CLL according to fitness and relevant genetic risk factors like IGHV mutational status and TP53 aberrations.

Selecting the optimal BTK inhibitor therapy in CLL: rationale and practical considerations

Bruton's tyrosine kinase (BTK) inhibitors have dramatically changed the treatment of newly diagnosed and relapsed/refractory chronic lymphocytic leukemia (CLL). Ibrutinib, acalabrutinib, and zanubrutinib are Food and Drug Administration (FDA)-approved BTK inhibitors that have all demonstrated progression-free survival (PFS) benefit compared with chemoimmunotherapy. The efficacy of these agents compared to one another is under study; however, current data suggest they provide similar efficacy. Selectivity for BTK confers different adverse effect profiles, and longer follow-up and real-world use have characterized side effects over time. The choice of BTK inhibitor is largely patient-specific, and this review aims to highlight the differences among the agents and guide the choice of BTK inhibitor in clinical practice.

Case report: Zanubrutinib-induced dermatological toxicities: A single-center experience and review

Zanubrutinib, a next-generation non-covalent Bruton’s tyrosine kinase (BTK) inhibitor, shows great efficacy in the treatment of B cell malignancies. Some patients may experience a series of side effects after the treatment of zanubrutinib. Grade 4 dermatological toxicities are rare, which present as severe rash and skin infection. Herein, we retrospectively reported the grade 4 dermatological toxicities of zanubrutinib in three consecutive patients. They were treated with zanubrutinib 160 mg twice daily orally. One patient was diagnosed with Primary Breast Diffuse Large B-cell Lymphoma(PB-DLBCL) and two patients were diagnosed with Chronic Lymphocytic Leukemia(CLL). Within one month after zanubrutinib treatment, all three patients developed grade 4 dermatological toxicities, including bruising, maculopapular rash, petechiae, ecchymosis, hemorrhagic blister, acne-Like rash, papulopustular rash, and skin infections. Zanubrutinib was discontinued in two patients due to unacceptable dermatological toxicities. Safety data from pre-licensing clinical trials showed that zanubrutinib-related side effects were frequent but well tolerated. To date, no severe dermatological toxicities were reported. The majority of patients can be relieved with symptomatic treatment, but a very small percentage of patients may face discontinuation of the drug.

Use of BTK Inhibitors in Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma (CLL/SLL): A Practical Guidance

The treatment landscape of chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) has changed significantly since the development of oral Bruton's tyrosine kinase (BTK) inhibitors. While chemoimmunotherapy was previously the standard of care for first-line treatment, BTK inhibitors have proven to be a highly effective and safe therapeutic option for CLL/SLL, and now constitute one of the preferred first-line options. Ibrutinib, the first approved covalent BTK inhibitor in CLL/SLL, has the most long-term data supporting its efficacy in CLL/SLL treatment although is associated with increased risk of cardiovascular and hemorrhage adverse events due to off-target kinase inhibition. The second-generation covalent BTK inhibitors, including acalabrutinib and zanubrutinib, are more selective to BTK with less off-target effects. Resistance to covalent BTK inhibitors may emerge over time due to mutations in BTK and downstream kinases. Novel non-covalent BTK inhibitors currently being studied are showing promising activities to overcome such resistance. In this review, we discuss the role of BTK inhibitors in treatment of CLL/SLL, review the data that led to approval of BTK inhibitors in CLL/SLL, outline the toxicity profile of each approved BTK inhibitor and management, and give practical guidance on how to select the most appropriate agent for treatment.

The Role of Bruton's Kinase Inhibitors in Chronic Lymphocytic Leukemia: Current Status and Future Directions

The use of Bruton's tyrosine kinase (BTK) inhibitors has changed the management and clinical history of patients with chronic lymphocytic leukemia (CLL). BTK is a critical molecule that interconnects B-cell antigen receptor (BCR) signaling. BTKis are classified into two categories: irreversible (covalent) inhibitors and reversible (non-covalent) inhibitors. Ibrutinib was the first irreversible BTK inhibitor approved by the U.S. Food and Drug Administration in 2013 as a breakthrough therapy in CLL patients. Subsequently, several studies have evaluated the efficacy and safety of new agents with reduced toxicity when compared with ibrutinib. Two other irreversible, second-generation BTK inhibitors, acalabrutinib and zanubrutinib, were developed to reduce ibrutinib-mediated adverse effects. Additionally, new reversible BTK inhibitors are currently under development in early-phase studies to improve their activity and to diminish adverse effects. This review summarizes the pharmacology, clinical efficacy, safety, dosing, and drug-drug interactions associated with the treatment of CLL with BTK inhibitors and examines their further implications.

Outcomes for Recurrent Mantle Cell Lymphoma Post-Ibrutinib Therapy: A Retrospective Cohort Study from a Japanese Administrative Database

INTRODUCTION

Treatment options in patients with mantle cell lymphoma (MCL) failing ibrutinib are limited, with no standard therapies defined. This study aimed to investigate real-world treatment patterns and outcomes for patients with MCL following ibrutinib.

METHODS

This study utilized a de-identified hospital-based claims database (Medical Data Vision) in Japan. Eligible patients were adults who were diagnosed with MCL and had received antitumor drugs between December 2010 and July 2020. Patients were followed from the first antitumor drug treatment until the end of available data up to July 2021. Time-to-event analyses utilized the Kaplan-Meier method. Factors for receiving post-ibrutinib therapy were explored with logistic regression analysis.

RESULTS

Of the 1386 patients who started antitumor drug therapy, 247 patients received and discontinued ibrutinib at any line of therapy. Among them, 137 patients (55.5%) received subsequent therapy. The median age at the end of ibrutinib therapy was 77 (range 42-95), and 44 patients had a dependent activity of daily living (ADL). Factors negatively associated with receiving post-ibrutinib therapy after discontinuation of ibrutinib were age ≥ 75 years (odds ratio [95% CI] 0.46 [0.26-0.80]) and emergency hospital admissions (0.37 [0.17-0.84]). Immediate post-ibrutinib therapy regimens were highly diverse, with BR (bendamustine, rituximab) only prescribed in more than 10% of patients. The median duration of post-ibrutinib therapy was 1.5 months (95% CI 1.07-2.07). The median overall survival from the end of ibrutinib therapy in patients regardless of the receipt of post-ibrutinib therapy (n = 247), in those who did not receive post-ibrutinib therapy (n = 110), and in those who received post-ibrutinib therapy (n = 137) was 5.6 months (95% CI 3.8-8.7), 2.3 months (95% CI 1.2-3.9), and 8.7 months (95% CI 5.6-13.8), respectively. The most common adverse event during post-ibrutinib therapy was infection, with the use of anti-infectives (17%).

CONCLUSIONS

Patients with MCL previously treated with ibrutinib have poor ability to carry out ADL and experience very poor outcomes. New safe, effective therapies are needed.