Real-world outcomes of ibrutinib therapy in Korean patients with relapsed or refractory mantle cell lymphoma: a multicenter, retrospective analysis

Unmet needs in relapsed/refractory mantle cell lymphoma (r/r MCL) post-covalent Bruton tyrosine kinase inhibitor (BTKi): a systematic literature review and meta-analysis

To quantify the clinical unmet need of r/r MCL patients who progress on a covalent Bruton tyrosine kinase inhibitor (BTKi), we conducted a systematic review to identify studies that reported overall survival (OS), progression-free survival (PFS), or response outcomes of patients who received a chemo(immunotherapy) ± targeted agent standard therapy (STx) or brexucabtagene autoleucel (brexu-cel) in the post-BTKi setting. Twenty-six studies (23 observational; three trials) reporting outcomes from 2005 to 2022 were included. Using two-stage frequentist meta-analyses, the estimated median PFS/OS for patients treated with an STx was 7.6 months (95% CI: 3.9-14.6) and 9.1 months (95% CI: 7.3-11.3), respectively. The estimated objective response rate (ORR) was 45% (95% CI: 34-57%). For patients treated with brexu-cel, the estimated median PFS/OS was 14.9 months (95% CI: 10.5-21.0) and 32.1 months (95% CI: 25.2-41.2), with a pooled ORR of 89% (95% CI: 86-91%). Our findings highlight a significant unmet need for patients whose disease progresses on a covalent BTKi.

Real-World Evidence of Relapsed/Refractory Mantle Cell Lymphoma Patients and Treatments: A Systematic Review

Introduction

Mantle cell lymphoma (MCL) is an incurable disease with an aggressive clinical course, and most patients eventually relapse after chemotherapy. Targeted therapies developed for relapsed/refractory MCL have been approved based on clinical trial data. However, real-world setting data are scarce and scattered.

Areas Covered

This systematic review aimed to collect, synthesize, and describe the characteristics and treatment outcomes of patients with relapsed/refractory MCL after receiving a second or subsequent line of therapy in the real-world setting.

Expert Opinion

R/R MCL is clinically and biologically heterogeneous and still represents a therapeutic challenge, with high-risk and early relapsed patients remaining an unmet medical need. This systematic review is limited by the quality of the available data and the difficulty of comparing outcomes in R/R MCL due to the heterogeneity of the disease, but the results suggest that covalent BTKis should be positioned as second-line therapy, followed by CAR T-cells in BTK-i-relapsed patients. Chemo-free and combination therapies with established chemoimmunotherapy backbones in the relapsed and front-line settings have been recently developed, and front-line options are being improved to move targeted and cellular therapies to earlier lines, including front-line therapy, in elderly and younger fit patients. In the upcoming years, many new targeted agents will play an important role and will be incorporated to the routine practice as their sequence, and outcomes in unselected patients are determined.

Death from mantle cell lymphoma limits sequential therapy, particularly after first relapse: Patterns of care and outcomes in a series from Australia and the United Kingdom

Mantle cell lymphoma (MCL) is a B-cell non-Hodgkin lymphoma characterised by a heterogeneous clinical course. Patients can often receive sequential treatments, yet these typically yield diminishing periods of disease control, raising questions about optimal therapy sequencing. Novel agents, such as chimeric antigen receptor T-cell therapies and bispecific antibodies, show promise in relapsed MCL, but are often reserved for later treatment lines, which may underserve patients with aggressive disease phenotypes who die early in the treatment journey. To assess the problem of patient attrition from lymphoma-related death limiting sequential treatment, we performed a multicentre retrospective cohort analysis of 389 patients treated at Australian and UK centres over a 10-year period. Deaths from MCL increased after each treatment line, with 7%, 23% and 26% of patients dying from uncontrolled MCL after first, second and third lines respectively. Patients with older age at diagnosis and early relapse after induction therapy were at particular risk of death after second-line treatment. This limitation of sequential treatment by lymphoma-related death provides support for the trial of novel therapies in earlier treatment lines, particularly in high-risk patient populations.

A retrospective analysis of ibrutinib outcomes in relapsed or refractory mantle cell lymphoma

Background

While treatment strategies for mantle cell lymphoma (MCL) have evolved, patients often experience disease progression and require additional treatment therapies. Ibrutinib presents a promising option for relapsed or refractory MCL (RR-MCL). This study investigated real-world treatment outcomes of ibrutinib in patients with RR-MCL.

Methods

A single-center retrospective analysis investigated clinical characteristics and survival outcomes of patients with RR-MCL, treated with ibrutinib.

Results

Forty-two patients were included, with 16 received rituximab and bendamustine, and 26 receiving anthracycline-based regimens as front-line treatment. During a median follow-up of 46.0 months, the response rate to ibrutinib was 69%, with 12 CRs and 8 partial responses. Disease progression (54.8%) and adverse events (11.9%) were the primary reasons for discontinuation. Median progression-free survival (PFS) and overall survival (OS) were approximately 16.4 and 50.1 months, respectively. Patients older than 70 years (P=0.044 and P=0.006), those with splenomegaly (P=0.022 and P=0.006), and those with a high-risk simplified Mantle Cell Lymphoma International Prognostic Index (sMIPI) (P＜0.001 and P＜0.001) exhibited siginificantly inferior PFS and OS. Notably, patients with a high-risk sMIPI relapsed earlier. Post-ibrutinib treatment yilded an OS of 12.2 months, while clinical trial participants demonstrated superior survival compared to those receiving chemotherapy alone.

Conclusion

This study underscores the importance of considering patient characteristics before administering ibrutinib as salvage therapy. Early relapse was associated with poor outcomes, highlighting the need for novel therapeutic strategies.

IBRORS-MCL study: a Spanish retrospective and observational study of relapsed/refractory mantle-cell lymphoma treated with ibrutinib in routine clinical practice

This retrospective study evaluated 66 patients diagnosed with relapsed and/or refractory mantle cell lymphoma (R/R MCL) treated with ibrutinib in Spain in routine clinical practice. At diagnosis, patients had a median age of 64.5 years, 63.6% presented with intermediate/high sMIPI (simplified prognostic index for advanced-stage mantle cell lymphoma), 24.5% had the blastoid variant, and 55.6% had a Ki67 > 30%. Patients had received a median of 2 prior lines of therapy (range 1-2; min-max 1-7). Overall response rate was 63.5%, with 38.1% of patients achieving complete response (CR). With a median duration of ibrutinib exposure of 10.7 months (range 5.2-19.6; min-max 0.3-36), the median progression-free survival (PFS) and overall survival (OS) were 20 months [95% confidence interval (CI) 8.8-31.1] and 32 months (95% CI 22.6-41.3), respectively, and were not reached in patients achieving CR. No grade ≥ 3 cardiovascular toxicity or bleeding was reported. This study supports that treatment with ibrutinib leads to high response rates and favorable survival outcomes in patients with R/R MCL.

Ibrutinib as monotherapy versus combination therapy in Chinese patients with relapsed/refractory mantle cell lymphoma: A multicenter study

BACKGROUND

Ibrutinib has revolutionized the treatment of mantle cell lymphoma (MCL). Both ibrutinib monotherapy and ibrutinib-based combination therapy are important salvage options for patients with relapsed/refractory (R/R) MCL. The real-world efficacy and safety profile of the two strategies in Chinese patients with R/R MCL remain unclarified.

METHODS

In the present study, data of 121 R/R MCL patients who received either ibrutinib monotherapy (N = 68) or ibrutinib combination therapy (N = 53) in 13 medical centers in China were retrospectively reviewed.

RESULTS

With a median follow-up of 20.5 months, the overall response rate was 60.3% versus 84.9% (p = 0.003), complete remission rate was 16.2% versus 43.4% (p < 0.001), and median progression-free survival (PFS) was 18.5 months (95% confidence interval [CI], 12.1-21.8) vs. 30.8 months (95% CI, 23.5-NR) (hazard ratio, 0.53 [95% CI, 0.30-0.93]; p = 0.025), with ibrutinib monotherapy and ibrutinib-based combination therapy, respectively. Subgroup analysis showed that patients with male gender, no refractory disease, Ki67 <30%, previous line of therapy = 1, non-blastoid subtype, and the number of extranodal sites involved <2 might benefits more from the combination therapy. Treatment-emergent adverse events were similar, except for a higher incidence of all grade neutropenia in the ibrutinib combination group (12.7% vs. 32.0%, p = 0.017).

CONCLUSIONS

Ibrutinib combination therapy demonstrated potentially superior efficacy and comparable tolerability to ibrutinib monotherapy. Ibrutinib-based combination therapy could be one of the prominent treatment options for R/R MCL patients.