Pembrolizumab plus lenvatinib in second-line and third-line patients with pleural mesothelioma (PEMMELA): a single-arm phase 2 study

Immunotherapy in mesothelioma - systematic review and meta-analysis of immunotherapy impact on OS and its correlation with PFS and ORR

Mesothelioma has a poor prognosis, with a 5-year overall survival (OS) rate less than 5%. Immunotherapy has been proven as a promising alternative to platinum-based therapies in first-line treatment. Our systematic literature search included 7 randomized clinical trials involving 2,549 patients to evaluate the impact of immunotherapy on OS across different lines of therapy, histologic subtypes, and ECOG performance status, and to assess the correlation between OS, progression-free survival (PFS), and objective response rate (ORR). Immunotherapy significantly improved OS (HR 0.78, P = 0.0005) with a similar benefit observed in first-line and second/later-line treatment (P = 0.25) as well as in all ECOG statuses (P = 0.32). A significantly greater benefit was observed in non-epithelioid compared to epithelioid mesothelioma (P = 0.002). Additionally, a strong correlation was shown only between OS and PFS (r = 0.86, P = 0.01). Our results emphasize the importance of immunotherapy in mesothelioma and further support PFS as a surrogate endpoint.

Current drug therapy for pleural mesothelioma

Pleural mesothelioma (PM) is a rare and highly aggressive malignancy originating from the pleural lining, with a median overall survival of merely 1 year. This cancer primarily arises from mesothelial cells following exposure to carcinogenic, biopersistent mineral fibers, particularly asbestos. The histological subtypes of mesothelioma are epithelioid (approximately 60%), sarcomatoid (20%), and biphasic (20%), exhibiting epithelioid and sarcomatoid characteristics. Classification is important for prognosis and guides the therapeutic strategy. Due to the typical late presentation, most patients with PM are ineligible for localized treatments such as surgery or radiotherapy. Systemic therapy, including cytotoxic chemotherapy, targeted therapies, and immunotherapy, is thus critical for managing advanced PM. For unresectable PM, decisions regarding systemic treatment are guided by patient suitability and histological characteristics. First-line therapies for advanced PM currently include the cisplatin-pemetrexed combination and the nivolumab-ipilimumab regimen. Historically, cisplatin-pemetrexed has been administered as first-line treatment, though recent advancements have introduced new therapies that significantly prolong patient survival. Innovative approaches combining immunotherapy and chemotherapy offer promising avenues for further improvement. Future treatment strategies should incorporate novel paradigms, such as combination chemo-immunotherapy, targeted agents, and potential cellular therapies, alongside companion biomarkers tailored to the histologic and molecular diversity of mesothelioma. This review explores the latest advancements in drug therapy for PM and provides an overview of current systemic treatment options.

Follow-up after first-Line nivOlumab plus ipilimumab in patients with diffuse pleuRal mesotheliomA: a real-world Dutch cohort study-FLORA

BACKGROUND

Diffuse pleural mesothelioma (dPM) is an aggressive malignancy, primarily treated with palliative systemic therapy. Since 2022, nivolumab-ipilimumab (nivo/ipi) has replaced chemotherapy as the standard first-line treatment for dPM in the Netherlands. Chemotherapy remains a rational second-line treatment. The real-world effectiveness of second-line treatment after doublet immunotherapy remains unknown. The FLORA study aimed to provide an overview of treatment patterns in patients with dPM after first-line nivo/ipi and evaluate the effectiveness of second-line chemotherapy based on real-world data.

PATIENTS AND METHODS

FLORA was a Dutch multicenter retrospective cohort study. Clinical data were collected from the medical records. The primary endpoints were treatment patterns after nivo/ipi and median overall survival (mOS) of patients receiving second-line chemotherapy. The secondary endpoints were objective response rate (ORR), median progression-free survival (mPFS) of second-line chemotherapy, and subgroup analyses (Eastern Cooperative Oncology Group performance status and histological subtype). The study also updated the mOS for first-line nivo/ipi patients.

RESULTS

Between May 2021 and July 2023, 277 patients with dPM receiving first-line nivo/ipi therapy were included. Sixty-eight percent of the patients were male, with a median age of 72 years (interquartile range 67-77 years). The histological subtypes were epithelioid (62%), sarcomatoid (22%), biphasic (13%), and unknown (3%). One hundred and two (47%) of the 218 patients with disease progression received second-line treatment, of whom 83 received second-line platinum-pemetrexed chemotherapy. The mOS and mPFS for second-line chemotherapy were 8.2 months ([95% confidence interval (CI) 7.4-9.1 months] and 5.6 months (95% CI 4.9-6.3 months), respectively, with an ORR of 37%. Poor performance score was the main reason for not receiving second-line treatment.

CONCLUSION

This study provides the first real-world data on subsequent treatment of patients with dPM with disease progression on nivo/ipi, resulting in an mOS of 8.2 months after second-line chemotherapy.

The presence of pleural effusion is an independent prognostic factor in patients with malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is a rare form of thoracic malignancy with a poor prognosis. Pleural effusion (PE) occurs in the majority of patients with MPM; however, its impact on MPM outcomes remains controversial. We searched for eligible patients from the Surveillance, Epidemiology, and End Results (SEER) database, and clinicopathological information and outcomes were collected. Cox proportional hazard regression analyses were utilized to evaluate the association of PE and other factors with overall survival (OS) and cancer-specific survival (CSS) in patients with MPM. A total of 4185 patients were extracted from the SEER database from 2000 to 2021. The median age of the cohort was 73 years, with a predominance of male patients and epithelioid MPM as the main histological subtype. Univariate Cox regression revealed associations between PE, age, sex, marital status, histology, stage, and treatment with both OS and CSS. Besides, multivariate analyses indicated that PE was independently associated with poorer OS and CSS in patients with MPM, regardless of age, sex, histology, stage, and treatment. Subgroup analyses suggested that PE has a remarkable impact on patients undergoing surgery. PE might serve as an independent prognostic factor in patients with MPM, especially in surgery recipients. Consequently, the development of pleural effusion in these patients should receive increased attention. Future studies are needed to validate these findings, particularly concerning the effect of PE in other clinical settings, such as immunotherapy.

Unleashing precision: A review of targeted approaches in pleural mesothelioma

This review delves into the intricate landscape of pleural mesothelioma (PM), emphasizing the need for nuanced therapeutic strategies. While platinum-based chemotherapy remains a cornerstone, the advent of immune checkpoint inhibitors (ICIs), notably through the Checkmate 743 trial, has reshaped treatment paradigms. Challenges persist due to patient heterogeneity and a lack of specific biomarkers. Targeting genotypic and phenotypic alterations emerges as a promising avenue, demanding precision oncology in this rare disease. CDKN2A loss, prevalent in PM, may respond to CDK4/6 inhibitors. Defects in MMR and HR suggest tailored approaches with ICI or PARP inhibitors, respectively. Ongoing trials explore novel inhibitors and promising targets like mesothelin. Implementing these strategies requires overcoming challenges in patient selection, combination therapies, biomarker identification, and cost considerations. Collaboration is crucial for transforming these insights into impactful clinical interventions, heralding the era of personalized and precision medicine for PM.

Genomic and T cell repertoire biomarkers associated with malignant mesothelioma survival

BACKGROUND

Malignant mesothelioma (MM) is an exceedingly rare tumor with poor prognosis due to the limited availability of effective treatment. Immunotherapy has emerged as a novel treatment approach for MM, but less than 40% of the patients benefit from it. Thus, it is necessary to identify accurate and effective biomarkers that can predict the overall survival (OS) and immunotherapy efficacy for MM.

METHODS

DNA sequencing was used to identify the genomic landscape based on the data from 86 Chinese patients. T cell receptor (TCR) sequencing was used to characterize MM TCR repertoires of 28 patients between October 2016 and April 2023.

RESULTS

Patients with TP53, NF2, or CDKN2A variants at the genomic level, as well as those exhibiting lower Shannon index (<6.637), lower evenness (<0.028), or higher clonality (≥0.194) according to baseline tumor tissue TCR indexes, demonstrated poorer OS. Furthermore, patients with TP53, CDKN2A, or CDKN2B variants and those with a lower evenness (<0.030) in baseline tumor tissue showed worse immunotherapy efficacy. The present study is the first to identify five special TCR Vβ-Jβ rearrangements associated with MM immunotherapy efficacy.

CONCLUSIONS

The present study reported the largest-scale genomic landscape and TCR repertoire of MM in Chinese patients and identified genomic and TCR biomarkers for the prognosis and immunotherapy efficacy in MM. The study results might provide new insights for prospective MM trials using specific genes, TCR indexes, and TCR clones as biomarkers and offer a reference for future antitumor drugs based on TCR-specific clones.