Real-world outcomes of PD-L1 inhibitors combined with thoracic radiotherapy in the first-line treatment of extensive stage small cell lung cancer

Clinical outcomes and synergistic effect between radiotherapy and immunotherapy in patients with extensive-stage small cell lung cancer: a real-world study

BACKGROUND

Patients with extensive-stage small cell lung cancer (ES-SCLC) experience significant therapeutic challenges and limited survival rates. This study aimed to investigate the efficacy of combining immunotherapy (IT) with chemotherapy (CT) for treating ES-SCLC and to explore the synergistic effect between radiotherapy (RT) and IT.

METHODS

This retrospective analysis examined patients with ES-SCLC who received treatment at three centers. Furthermore, propensity score-matched (PSM) analysis was conducted. The Kaplan‒Meier method and Cox proportional hazards regression were used to compare the survival outcomes.

RESULTS

A total of 257 eligible patients with ES-SCLC were included in the analysis. Among all patients, the median overall survival (mOS) was 18.0 m in the chemoimmunotherapy (CT + IT) group and 15.7 m in the CT group (p = 0.208). The median real-world progression-free survival (mrwPFS) was 7.7 m and 6.8 m (p = 0.043) in the CT + IT and CT group, respectively. Moreover, the mOS was 22.0 m in the chemoradiotherapy (CT + RT) group and 13.6 m in the CT group (p < 0.001). The mrwPFS was 7.4 m and 6.0 m (p = 0.175) in the CT + RT group and CT group, respectively. The multivariate analyses revealed that sex, liver metastasis and RT were independent prognostic factors for OS (p < 0.05), while liver metastasis and IT were found to be independent predictive factors of real-world progression-free survival (rwPFS) (p < 0.05). After PSM, the mOS was 23.2 m in the CT + IT group and 13.0 m in the CT group (p = 0.008). The mrwPFS was 7.3 m and 6.2 m (p = 0.096) in the CT + IT group and the CT group, respectively. Moreover, the mOS was 21.4 m in the CT + RT group and 12.5 m in the CT group (p < 0.001). The mrwPFS was 7.3 m and 5.2 m (p = 0.220) in the CT + RT group and the CT group, respectively. Additionally, our study revealed that in the PD-1 group, RT significantly improved patient survival (36.0 m vs. 15.8 m, p = 0.041).

CONCLUSION

An increasing number of treatment options are being explored for ES-SCLC, and CT is the cornerstone of treatment for this disease. Combining CT with IT and RT has demonstrated remarkable efficacy and excellent safety profiles, and such treatments are worthy of further exploration.

Adebrelimab plus chemotherapy and sequential thoracic radiotherapy as first-line therapy for extensive-stage small-cell lung cancer (ES-SCLC): a phase II trial

Background

This phase II prospective trial aimed to investigate the efficacy and safety of adebrelimab (PD-L1 antibody) plus first-line chemotherapy followed by sequential thoracic radiotherapy (TRT) combined with adebrelimab in extensive-stage small-cell lung cancer (ES-SCLC). Biomarkers associated with potential therapeutic effects were also explored.

Methods

Patients with previously untreated ES-SCLC were enrolled at Shandong Cancer Hospital and Institute (Jinan, China). Patients received 4-6 cycles of adebrelimab (20 mg/kg, D1, Q3W) combined with EP/EC (etoposide, 100 mg/m2, D1-3, Q3W and cisplatin, 75 mg/m2, D1, Q3W or carboplatin, AUC = 5, D1, Q3W). Then patients with response sequentially underwent consolidative TRT (≥30 Gy in 10 fractions or ≥50 Gy in 25 fractions, involved-field irradiation), and maintenance adebrelimab until disease progression or intolerable adverse events (AEs). The primary endpoint was overall survival (OS). Genomic and circulating tumour DNA (ctDNA) profiling were also analyzed with tumour tissues and peripheral blood. This trial was registered with ClinicalTrials.gov, NCT04562337.

Findings

From October 2020 to April 2023, 67 patients diagnosed with ES-SCLC were enrolled and received at least one dose of study treatment. All patients were included in the efficacy and safety analyses. 45 patients received sequential TRT as planned. The median OS and progression-free survival (PFS) was 21.4 months (95% CI: 17.2-not reached months) and 10.1 months (95% CI: 6.9-15.5 months), respectively. The confirmed objective response rate was 71.6% (48/67, 95% CI: 59.3-82.0%) and disease control rate was 89.6% (60/67, 95% CI: 79.7-95.7%). There were no treatment-related deaths. The most common grade 3 or higher treatment-related adverse events (TRAEs) were hematological toxicities. The incidence of any grade and G3+ pneumonitis was 25% (17/67) and 6% (4/67), respectively. No unexpected adverse events were observed. Patients without co-mutations of TP53/RB1 in both tissue and peripheral blood displayed longer PFS (tissue, P = 0.071; ctDNA, P = 0.060) and OS (tissue, P = 0.032; ctDNA, P = 0.031).

Interpretation

Adebrelimab plus chemotherapy and sequential TRT as first-line therapy for ES-SCLC showed promising efficacy and acceptable safety.

Funding

This study was funded by the National Natural Science Foundation of China (82172865), Jiangsu Hengrui Pharmaceuticals Co., Ltd. and Amoy Diagnostics Co., Ltd.

Real-world impact of the introduction of chemo-immunotherapy in extended small cell lung cancer: a multicentric analysis

Background

Recent clinical trials demonstrated longer survival in extended small cell lung cancer (SCLC) patients treated with immunotherapy in addition to chemotherapy. However, the magnitude of benefit is modest and the impact in real-world setting has to be fully established.

Methods

We collected clinical data and radiological imaging of patients affected by extended or relapsing SCLC and consecutively treated according to clinical practice between 2016 and 2023. As primary end-point, we compared pre-defined outcome indicators before and after the introduction of chemo-immunotherapy (May 2020): 6-month and 12-month progression free survival (PFS) rate, 12-month and 18-month overall survival (OS). Among those who were treated after May 2020, patients who did not receive immunotherapy according to treating physician's choice were included in the analysis to minimize clinical selection bias.

Results

The analysis included 214 patients: 132 (61.7%) were treated in an Academic cancer center and 82 (38.3%) in two community hospitals; 104 were treated before May 2020. Median PFS of the overall study population was 4.8 months (95% confidence interval [95% CI]: 4.4-5.4), median OS was 7.1 months (95% CI: 6.3-7.7). Estimated PFS and OS were significantly longer in patients treated after May 2020 with hazard ratio (HR) for PFS and OS of 0.61 (95% CI: 0.46-0.81, p < 0.001) and 0.70 (95% CI: 0.52-0.93, p = 0.015), respectively. 6-month PFS rate increased from 27% to 40% (p = 0.04) while 12-months PFS raised from 1% to 11% (p = 0.003). 12-month and 18-month OS rate increased from 15% to 28% (p = 0.03) and from 2.1% to 12% (p = 0.009), respectively. After May 2020 the median number of hospitalization days per patient decreased significantly and the incidence of severe AEs was similar. Among patients treated with chemo-immunotherapy, the onset of immune-related AEs was associated with improved PFS and OS (HR 0.55, 95% CI: 0.35-0.89, p = 0.012 and HR 0.47, 95%CI 0.28-0.77, p = 0.002, respectively).

Conclusions

The real-world analysis shows a meaningful improvement of outcome indicators after the introduction of chemo-immunotherapy, with reduction of the duration of hospitalization, thus supporting the use of chemo-immunotherapy and the need for further biomarker research.

Consolidative thoracic radiation therapy for extensive-stage small cell lung cancer in the era of first-line chemoimmunotherapy: preclinical data and a retrospective study in Southern Italy

Background

Consolidative thoracic radiotherapy (TRT) has been commonly used in the management of extensive-stage small cell lung cancer (ES-SCLC). Nevertheless, phase III trials exploring first-line chemoimmunotherapy have excluded this treatment approach. However, there is a strong biological rationale to support the use of radiotherapy (RT) as a boost to sustain anti-tumor immune responses. Currently, the benefit of TRT after chemoimmunotherapy remains unclear. The present report describes the real-world experiences of 120 patients with ES-SCLC treated with different chemoimmunotherapy combinations. Preclinical data supporting the hypothesis of anti-tumor immune responses induced by RT are also presented.

Methods

A total of 120 ES-SCLC patients treated with chemoimmunotherapy since 2019 in the South of Italy were retrospectively analyzed. None of the patients included in the analysis experienced disease progression after undergoing first-line chemoimmunotherapy. Of these, 59 patients underwent TRT after a multidisciplinary decision by the treatment team. Patient characteristics, chemoimmunotherapy schedule, and timing of TRT onset were assessed. Safety served as the primary endpoint, while efficacy measured in terms of overall survival (OS) and progression-free survival (PFS) was used as the secondary endpoint. Immune pathway activation induced by RT in SCLC cells was explored to investigate the biological rationale for combining RT and immunotherapy.

Results

Preclinical data supported the activation of innate immune pathways, including the STimulator of INterferon pathway (STING), gamma-interferon-inducible protein (IFI-16), and mitochondrial antiviral-signaling protein (MAVS) related to DNA and RNA release. Clinical data showed that TRT was associated with a good safety profile. Of the 59 patients treated with TRT, only 10% experienced radiation toxicity, while no ≥ G3 radiation-induced adverse events occurred. The median time for TRT onset after cycles of chemoimmunotherapy was 62 days. Total radiation dose and fraction dose of TRT include from 30 Gy in 10 fractions, up to definitive dose in selected patients. Consolidative TRT was associated with a significantly longer PFS than systemic therapy alone (one-year PFS of 61% vs. 31%, p<0.001), with a trend toward improved OS (one-year OS of 80% vs. 61%, p=0.027).

Conclusion

Multi-center data from establishments in the South of Italy provide a general confidence in using TRT as a consolidative strategy after chemoimmunotherapy. Considering the limits of a restrospective analysis, these preliminary results support the feasibility of the approach and encourage a prospective evaluation.

Chemoimmunotherapy combined with consolidative thoracic radiotherapy for extensive-stage small cell lung cancer: A systematic review and meta-analysis

INTRODUCTION

This study aimed to evaluate the efficacy and safety of chemoimmunotherapy combined with consolidative thoracic radiation therapy (cTRT) in patients with extensive-stage small cell lung cancer (ES-SCLC).

METHODS

A meta-analysis was conducted. PubMed, Embase, Web of Science, and the Cochrane Library were searched. The study was registered in PROSPERO (registration no. CRD42023410344).

RESULTS

A total of 4677 studies were initially screened and 15 studies encompassing a total of 1033 patients were included. Chemoimmunotherapy combined with cTRT significantly improved survival (HR = 0.52, 95 % CI: 0.39, 0.68) with favorable 6-month (0.89, 95 % CI: 0.77, 1.00) and 1-year (0.77, 95 % CI: 0.72, 0.82) OS, without affecting ≥3 grade TRAEs (RR = 1.29, 95 % CI: 0.85, 1.98). Pooled 6-month and 1-year PFS were 0.67 (95 % CI: 0.47, 0.86) and 0.38 (95 % CI: 0.22, 0.55), respectively. Incidence of ≥3 grade TRAEs was 0.24 (95 % CI: 0.08, 0.39) and radiation pneumonitis was 0.03 (95 % CI: 0.01, 0.06).

CONCLUSIONS

Chemoimmunotherapy combined with cTRT improves survival and shows favorable outcomes in ES-SCLC patients, with manageable adverse events. Further research with larger samples is needed to confirm these findings.

Treatment patterns and clinical outcomes in 157 patients with extensive-stage small cell lung cancer: real-world evidence from a single-center retrospective study

Background

Immune checkpoint inhibitors (ICIs) have changed the therapeutic options for extensive-stage small-cell lung cancer (ES-SCLC). In this real-world study, we analyzed the treatment patterns in patients with ES-SCLC and evaluated the efficacy of chemotherapy combined with immunotherapy as first-line therapy.

Methods

A retrospective analysis was performed on patients with ES-SCLC who received treatment at China-Japan Friendship Hospital (Beijing, China) between August 1, 2020, and April 30, 2023. The treatment patterns appeared in the form of Sunburst Chart and Sankey diagram. The survival analyses were conducted by Kaplan-Meier curves.

Results

A total of 157 patients with ES-SCLC were retrospectively included. According to first-line therapy, patients were divided into the chemotherapy (CT) group (n=82) and chemo-immunotherapy (CIT) group (n=75). The median treatment lines were 2[1, 2] and cycles were 8[5, 12], respectively. 82 patients received the second line of therapy, followed by 37 for the third, 15 for the fourth, 11 for the fifth, and 5 for the sixth. Overall, the treatment patterns involved 11 options including 12 chemotherapy regimens, 11 ICIs, and 4 targeted agents. The second-line treatment pattern had the most options (9) and regimens (43). In the first 3 lines, chemotherapy was the largest proportion of treatment options. The addition of ICIs prolonged progression-free survival from 6.77 (95% confidence interval [CI], 6.00-7.87) to 7.33 (95% CI, 6.03-9.80) months (hazard ratio [HR]=0.67, 95% CI, 0.47-0.95; P=0.025), overall survival from 12.97 (10.90-23.3) to 14.33 (12.67-NA) months without statistically significant difference (HR=0.86, 95% CI, 0.55-1.34; P=0.505).

Conclusion

The treatment options of patients with ES-SCLC are more diversified. Combination therapy is the current trend, where chemotherapy is the cornerstone. Meanwhile, ICIs participate in almost all lines of treatment. However, the clinical efficacy remains barely satisfactory. We are urgently expecting more breakthrough therapies except immunology will be applied in the clinic.