First-Line Benmelstobart Regimen Produces Longest PFS, OS to Date in ES-SCLC

First-line treatment with benmelstobart, anlotinib, and chemotherapy improves survival outcomes, when compared to chemotherapy alone, in patients with extensive-stage small cell lung cancer (ES-SCLC), according to research presented at the 2023 World Conference on Lung Cancer.

The benmelstobart regimen produced the longest progression-free survival (PFS) and overall survival (OS) seen with first-line treatment for ES-SCLC thus far, according to study presenter Ying Cheng, MD, of Jilin Cancer Hospital in Changchun, China.

Dr Cheng and colleagues evaluated the regimen in the phase 3 ETER701 trial (ClinicalTrials.gov Identifier: NCT04234607).

The trial included 738 patients with ES-SCLC who had received no prior systemic therapy. They were randomly assigned to receive 1 of 3 treatment regimens:

• Benmelstobart (1200 mg on day 1), anlotinib (12 mg on days 1-14), etoposide (100 mg/m² on days 1-3), and carboplatin (AUC 5 mg/mL/min on day 1) in 21-day cycles
• Placebo, anlotinib, etoposide, and carboplatin (at the same dosing schedule as above)
• Placebo, etoposide, and carboplatin (same dosing schedule).

After 4 cycles of induction, patients received maintenance with benmelstobart plus anlotinib, anlotinib alone, or placebo.

Dr Cheng presented data comparing the patients who received the benmelstobart regimen (n=246) to patients who received chemotherapy only (n=247). Baseline characteristics were generally well balanced between these arms. The median follow-up was 14.0 months.

The median PFS was 6.93 months in the benmelstobart arm and 4.21 months in the chemotherapy-alone arm (hazard ratio [HR], 0.32; 95% CI, 0.26-0.41; P <.0001). The 6-month PFS rate was 59.11% in the benmelstobart arm and 16.55% in the chemotherapy-alone arm. The 12-month PFS rate was 27.91% and 2.29%, respectively.

The median OS was 19.32 months in the benmelstobart arm and 11.89 months in the chemotherapy-alone arm (HR, 0.61; 95% CI, 0.46-0.79; P =.0002). The 12-month OS rate was 64.12% in the benmelstobart arm and 49.00% in the chemotherapy-alone arm. The 24-month OS rate was 41.83% and 24.24%, respectively.

The objective response rate was 81.30% in the benmelstobart arm and 66.80% in the chemotherapy-alone arm. The median duration of response was 5.75 months and 3.09 months, respectively (HR, 0.31; 95% CI, 0.24-0.41; P <.0001). 

The incidence of grade 3 or higher treatment-related adverse events (TRAEs) was 93.1% in the benmelstobart arm and 87.0% in the chemotherapy-alone arm. The most common grade 3 or higher TRAEs (in the benmelstobart arm and chemotherapy-only arm, respectively) were neutrophil count decrease (69.5% and 68.7%), platelet count decrease (49.6% and 35.8%), and white cell count decrease (38.2% and 34.6%).

There were 11 treatment-related deaths in the benmelstobart arm and 4 in the chemotherapy-only arm.

According to Dr Cheng, these results support the use of benmelstobart plus anlotinib and chemotherapy as a new first-line option for patients with ES-SCLC.

Disclosures: This research was supported by Chia Tai Tianqing Pharmaceutical Group Co., Ltd. No other disclosures were provided.

Reference

Cheng Y, Yang R, Chen J, et al. Benmelstobart with anlotinib plus chemotherapy as first-line therapy for ES-SCLC: A randomized, double-blind, phase III trial. Presented at WCLC 2023. September 9-12, 2023. Abstract OA01.03.

This article originally appeared on Cancer Therapy Advisor