Comparative effectiveness of second-line immune checkpoint inhibitor therapy versus chemotherapy for malignant pleural mesothelioma

Comparative efficacy of immune checkpoint inhibitors versus chemotherapy alone in diffuse pleural mesothelioma

BACKGROUND

This study aimed to investigate the effects of immune checkpoint inhibitors (ICIs) versus chemotherapy on the prognosis of real-world diffuse pleural mesothelioma patients in China.

METHODS

Clinical data of 90 patients with diffuse pleural mesothelioma from 2019 to 2022 were collected from Harbin Medical University Cancer Hospital. Patients were divided into two groups: the ICIs-treated group (n = 46) and the chemotherapy-only group (n = 44). The efficacy and safety of immunotherapy relative to chemotherapy at different treatment stages were explored.

RESULTS

The median progression-free survival (PFS) was 10.0 and 7.0 months, and the median overall survival (OS) was 24.7 and 15.8 months in the ICIs-treated group and the chemotherapy group, respectively. The ICIs-treated group showed an 11% increase in objective response rate (ORR) (52.2% vs. 41.0%) and an 8.0% increase in disease control rate (DCR) (78.3% vs. 70.0%) compared to the chemotherapy group. The Kaplan-Meier curves demonstrated significant PFS (HR: 0.61; 95% CI: 0.38-0.98; p = 0.038) and OS (HR: 0.47; 95% CI: 0.26-0.86; p = 0.011) benefits of receiving immunotherapy over chemotherapy alone. Subgroup analysis according to treatment timing showed the same trend.

CONCLUSION

In patients with nonsurgical diffuse pleural mesothelioma, immunotherapy achieved better survival benefits compared to chemotherapy in both first- and second-/third-line treatments. The early addition of immunotherapy improved survival in patients with nonsurgical diffuse pleural mesothelioma.

Phase 2 Trial of Nivolumab and Ramucirumab for Relapsed Mesothelioma: HCRN-LUN15-299

Introduction

We hypothesized that ramucirumab could increase previously reported objective response rate (ORR) of 11% of single-agent nivolumab in the second-line therapy of unresectable mesothelioma.

Methods

This was a cooperative group, single-arm, phase 2 trial enrolling patients with unresectable mesothelioma after progression on more than or equal to one pemetrexed-containing regimen. Ramucirumab and nivolumab were given intravenously every 14 days for up to 24 months. The primary end point was ORR; secondary end points were progression-free survival (PFS) rate at 24 weeks and overall survival (OS).

Results

Between April 2018 and October 2021, 34 patients were recruited. Median age was 72 (range: 40-89) years, 12% were women, and 79% of tumors had epithelial histology. Median follow-up was 10.2 months (interquartile range 19.6 mo [4.3-23.8]). ORR was 22.6% (95% confidence interval [CI]: 9.6%-41.1%) in all population and 43% (95% CI: 10%-82%) in patients with nonepithelioid histology. Of all patients, 45.2% (95% CI: 27.3%-64.0%) had stable disease. PFS rate at 24 weeks was 32% (95% CI: 17%-51%). Median PFS was 4.2 months (95% CI: 1.9-6.4 mo). Median OS was 12.5 months (95% CI: 6.3-23.5 mo). There was no grade greater than or equal to four toxicity. Programmed death-ligand 1 expression in the tumor did not correlate with benefit from treatment. Activation of tumor-infiltrating lymphocytes in response to treatment was associated with a trend toward improvement in PFS.

Conclusions

Nivolumab and ramucirumab combination was safe and generated PFS and OS rates and ORR that compare favorably with single-agent nivolumab in a similar patient population. The primary end point of 40% ORR was not reached. Further investigation of this regimen in mesothelioma with nonepithelioid histology may be warranted. Clinical Trial Information: NCT03502746.

Immunotherapy vs. Chemotherapy in Subsequent Treatment of Malignant Pleural Mesothelioma: Which Is Better?

(1) Background: Malignant pleural mesothelioma (MPM) is a rare but aggressive tumor arising from the pleural surface. For relapsed MPM, there is no accepted standard of- are for subsequent treatment. Thus, we aimed to compare the efficacy of chemotherapy, targeting drugs, and immune-checkpoint inhibitors (ICIs) as subsequent therapy for relapsed MPM. (2) Methods: The study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). We searched several acknowledged databases. Primary outcomes were defined as overall median progressive survival (mPFS) and median overall survival (mOS) in different treatment groups. Secondary outcomes were defined as objective response rate (ORR), the proportion of stable disease (SD), and progressive disease (PD). (3) Results: Ultimately, 43 articles were selected for the meta-analysis. According to the results of a pooled analysis of single-arm studies, ICIs showed a slight advantage in mOS, while chemotherapy showed a slight advantage in mPFS (mOS: 11.2 m vs. 10.39 m and mPFS: 4.42 m vs. 5.08 m for ICIs group and chemotherapy group, respectively). We identified only a few studies that directly compared the efficacy of ICIs with that of chemotherapy, and ICIs did not show significant benefits over chemotherapy based on mOS. (4) Conclusions: Based on current evidence, we considered that immunotherapy might not be superior to chemotherapy as a subsequent therapy for relapsed MPM. Although several studies investigated the efficacy of ICIs, targeting drugs, and chemotherapy in relapsed MPM, there was still no standard of care. Further randomized control trials with consistent criteria and outcomes are recommended to guide subsequent therapy in relapsed MPM and identify patients with certain characteristics that might benefit from such subsequent therapy.

Immune-Checkpoint Inhibitors for Malignant Pleural Mesothelioma: A French, Multicenter, Retrospective Real-World Study

Backgrounds: Malignant pleural mesothelioma (MPM) is a cancer with poor prognosis. Second-line and onward therapy has many options, including immune-checkpoint inhibitors with demonstrated efficacy: 10−25% objective response rate (ORR) and 40−70% disease-control rate (DCR) in clinical trials on selected patients. This study evaluated real-life 2L+ nivolumab efficacy in MPM patients and looked for factors predictive of response. Methods: This retrospective study included (September 2017−July 2021) all MPM patients managed in 11 French centers. Results: The 109 enrolled patients’ characteristics were: median age: 69 years; 67.9% men; 82.6% epithelioid subtype. Strictly, second-line nivolumab was given to 51.4%. Median PFS and OS were 3.8 (3.2−5.9) and 12.8 (9.2−16.4) months. ORR was 17/109 (15.6%); 34/109 patients had a stabilized disease (DCR 46.8%). Univariable analysis identified several parameters as significantly (p < 0.05) prognostic of OS [HR (95% CI)]: biphasic subtype: 3.3 (1.52−7.0), intermediate Lung Immune Prognostic Index score: 0.46 (0.22−0.99), progression on the line preceding nivolumab: 2.1 (1.11−3.9) and age > 70 years: 2.5 (1.5−4.0). Multivariable analyses retained only biphasic subtype: 3.57 (1.08−11.8) and albumin < 25 g/L: 10.28 (1.5−70.7) as significant and independent predictors. Conclusions: Second-line and onward nivolumab is effective against MPM in real life but with less effectiveness in >70 years. Ancillary studies are needed to identify the predictive factors.