In Phase 3 EMPOWER-Lung 1 study (NCT03088540), 1L CEMI monotherapy resulted in significantly longer OS and PFS versus chemotherapy (CHEMO) for pts with aNSCLC with no actionable genomic aberrations, whose tumours express PD-L1 ≥50%. The study included pts with treated, clinically stable, baseline brain metastases, a hard-to-treat and underrepresented population in clinical trials. We previously reported improved OS and PFS with 1L CEMI versus CHEMO for this subgroup. In this post hoc analysis, we report 3-year outcomes.
In EMPOWER-Lung 1, pts were randomised 1:1 to CEMI 350 mg IV Q3W or investigator’s choice of CHEMO. The overall median follow-up duration from randomization to data cut-off (4 March 2022) was 37.1 months (mo; range 24.0–56.5). Here, we analyzed pts with treated, clinically stable brain metastases (radiological stability not required).
In all, 69/565 (12.2%) pts with PD-L1 ≥50% had treated, clinically stable brain metastases at randomization. Baseline characteristics in CEMI (n=34) vs CHEMO (n=35) groups were: median age, 60.0 (range: 45–76) vs 62.0 (range: 48–77) yrs; male, 97.1% vs 82.9%; and non-squamous histology, 85.3% vs 74.3%. CEMI showed superior efficacy outcomes vs CHEMO: longer median OS (not reached vs 20.7 mo; HR=0.42, 0.20-0.87), longer median PFS (12.5 vs 5.3 mo; HR=0.34, 0.18–0.63), a higher ORR (55.9% vs 11.4%) and a longer median duration of response (31.7 mo vs 12.5 mo; Table). After baseline, disease progression in brain occurred in 5 (14.7%) pts with CEMI vs 7 (20%) with CHEMO. Incidence of grade ≥3 TEAEs was 35.3% in the CEMI group vs 60.0% in CHEMO.
| Clinical outcomes | Cemiplimab (n=34) | Chemotherapy (n=35) | HR (cemiplimab vs chemotherapy) |
| OS, mo, median (95% CI) | NR (20.6–NE) | 20.7 (9.1–29.9) | 0.42 (0.20–0.87); P=0.0168† |
| PFS, mo, median (95% CI) | 12.5 (6.1–33.5) | 5.3 (2.2–6.5) | 0.34 (0.18–0.63); P=0.0004† |
| ORR, %, (95% CI) | 55.9 (37.9–72.8) | 11.4 (3.2–26.7) | NA |
| Median (95% CI) duration of response (CR or PR), mo | 31.7 (14.7–NE) | 12.5 (4.4–NE) | NA |
| Data cutoff date 4 March 2022. | |||
Three-year follow up data shows durable clinical benefits and an acceptable safety profile with 1L CEMI monotherapy in subgroup analysis of pts with aNSCLC and brain metastases. CEMI is generally well tolerated in this subgroup.
NCT03088540
This study was funded by Regeneron Pharmaceuticals, Inc. Medical writing and editorial support was provided by John Facciponte, PhD, of Prime, Knutsford, UK, funded by Regeneron Pharmaceuticals, Inc., according to Good Publication Practice guidelines.