1474P - Outcome of nivolumab and ipilimumab-based therapy for advanced non-small cell lung cancer with low or negative PD-L1 expression

Background

Immunotherapy is currently the standard care for advanced non-small cell lung cancer (NSCLC) in the first line. The combination therapy of nivolumab and ipilimumab addresses an unmet clinical need, as single immune checkpoint inhibitor (ICI) therapy has limited efficacy in PD-L1-negative NSCLC. This combination therapy may also benefit patients with NSCLC who have low PD-L1 expression.

Methods

A retrospective, multicenter observational study was conducted to evaluate the efficacy of nivolumab and ipilimumab-based therapy (dual group) and single ICI-based therapy (single group) for patients with low or negative PD-L1 expression.

Results

Between December 2018 and October 2022, a total of 240 patients with advanced/recurrent NSCLC and low/negative PD-L1 expression who received combination immunotherapy were enrolled. The median age of the patients was 72 years. PD-L1 Tumor Proportion Score (TPS) was negative in 109 patients (45.4%), 1-10% in 69 patients (28.7%), 11-20% in 19 (7.9%), 21-30% in 21 (8.8%), and 31-49% in 17 (7.1%). The median observation period was 11.5 months. The single group consisted of 201 patients (83.8%) and the dual group consisted of 39 patients (16.2%). In the overall population, there was no significant difference in overall survival (OS) and progression-free survival (PFS) between both groups after propensity score matching. However, in the patients with PD-L1 TPS negative and 1-20%, the dual group had a tendency for longer PFS and OS than the single group. In the dual group, patients with PD-L1 TPS 0-20% had significantly longer PFS (10.5 months (5.0-NA) vs. 4.1 months (0.23-NA), p=0.017) and OS (NA months (18.6-NA) vs. 9.0 months (0.23-NA), p=0.0014) than those with PD-L1 TPS 21-49%. In the single group, there was no association between PD-L1 expression and PFS/OS.

Conclusions

The results suggest that nivolumab and ipilimumab-based therapy may be a better treatment option, especially for patients with negative and lower PD-L1 TPS (<20%). Updated results with a larger patient population and an extended observation period will be presented at upcoming congresses.

Clinical trial identification

UMIN000050723.

Editorial acknowledgement

Legal entity responsible for the study

Kobe University Graduate School of Medicine.

Funding

Has not received any funding.

Disclosure

M. Tachihara: Financial Interests, Personal, Invited Speaker: Eli Lilly Japan K.K., Chugai Pharmaceutical Co., Ltd, AstraZeneca K.K, MSD K.K., Ono Pharmaceutical Co., Ltd., Bristol Myers Squibb Co. Ltd.; Financial Interests, Personal and Institutional, Research Grant: AstraZeneca K.K. All other authors have declared no conflicts of interest.