KEY TAKEAWAYS
- The phase II trial aimed to assess the impact of ICIs on PFS and OS in stage 3 unresectable NSCLC pts following concurrent CRT.
- The result demonstrated that high CAML PD-L1 expression post-CRT may predict better outcomes for NSCLC pts with IMT, but prospective trials are needed.
For a study, researchers aimed to assess the impact of immune checkpoint inhibitors(ICIs) on progression-free survival(PFS) and overall survival(OS) in stage 3 unresectable NSCLC patients(pts) following concurrent CRT.
Utilizing 2 IMT treatment modalities, the study included concurrent CRT, atezolizumab (N=34), and another multi-year prospective study with standard CRT followed by consolidation durvalumab (N=48). A control group (n=82) treated with CRT alone, primarily before 2018, was included.
About 164 pts with confirmed unresectable stage 3 NSCLC underwent blood sample collection at Baseline (BL) and ~1 month post-CRT (T1). Blood was filtered using CellSieve, and CAMLs were quantified for PD-L1 expression with a binary score (low or high). PFS and OS HRs were assessed through censored univariate and multivariate analyses at 36 months.
In 91% of samples, an average of 6.6 CAMLs/15mL was observed. Additionally, 17 pts, initially treated with CRT alone, received post-recurrence IMT (i.e. n=4 atezolizumab, n=4 nivolumab, and n=9 pembrolizumab) for OS analysis only. PD-L1 expression (>1% using DAKO 22c3) didn’t predict CRT+IMT response (PFS HR 1.1 P=0.9856 & OS HR 1.4 p=0.49863).
High CAML PD-L1 at baseline wasn’t associated with PFS in CRT alone (HR 0.8 P=0.6032) or CRT+IMT (HR 1.1 p=0.9026). It also wasn’t associated with OS in CRT alone (HR 0.9 P=0.9577) or CRT+IMT (HR 1.3 P=0.5827). After CRT, high CAML PD-L1 at T1 predicted superior PFS in CRT+IMT (HR 2.6 P=0.0065) but not in CRT alone (HR 1.0 P=0.9544).
High CAML PD-L1 at T1 predicted better OS in CRT+IMT (HR 2.6 P=0.0075) but not in CRT alone (HR 1.4 P=0.4982). Among IMT pts (n=99), 57% maintained high PD-L1 at BL and T1 (N=27) or increased from BL to T1 (n=24).
IMT patients with high CAML PD-L1 at T1 had better outcomes than those with low CAML PD-L1 and better outcomes than patients treated with CRT alone. The result demonstrated that high CAML PD-L1 expression post-CRT may predict better outcomes for NSCLC pts with IMT, but prospective trials are needed.
Source: https://cattendee.abstractsonline.com/meeting/10925/presentation/938
Clinical Trial: https://clinicaltrials.gov/study/NCT02525757
Lin S, Seo A, Xu T, Tsao A, Heymach JV, Liao Z, Chang JY, Gardner KP, Moran JA, Tang C-M, Adams DL. The Predictive Value of PD-L1 levels on Circulating Stromal Cells in Unresectable Stage 3 NSCLC Treated with Chemoradiation. Presented at: The University of Texas MD Anderson Cancer Center; Houston, TX, USA. Creatv Microtech; Bethesda, MD, USA. September 11, 2023; 4:17 PM-4:27 PM
