Pembrolizumab monotherapy for non-small cell lung cancer (NSCLC): can patient stratification be improved in the UK Tayside population? A retrospective cohort study

OBJECTIVE

Pembrolizumab is a programmed cell death protein-1 (PD-1) inhibitor used to treat advanced patients with non-small cell lung cancer (NSCLC) with a programmed cell death ligand-1 (PD-L1) tumour proportion score (TPS) ≥50. Further sub-division of TPS-based stratification has not been evaluated in the UK, although smoking-induced tumour mutational burden and the immunogenic effects of prior radiotherapy are suggested to improve response.

AIMS

To investigate if PD-L1 TPS ≥80%, smoking status or radiotherapy before or within 2 months of treatment influenced progression-free survival (PFS) in patients with NSCLC treated with pembrolizumab monotherapy.

METHODS

PD-L1 TPS, smoking status and radiotherapy exposure were compared in patients with NSCLC in National Health Service (NHS) Tayside (n=100) treated with pembrolizumab monotherapy between 1 November 2017 and 18 February 2022. Survival estimates were compared using log-rank analysis, and Cox proportional hazards analysis was used to investigate the influence of potential confounding factors, including tumour stage and performance status.

RESULTS

PFS was not significantly different (log-rank HR=0.330, p=0.566) comparing patients with PD-L1 TPS 50-79% and PD-L1 TPS ≥80%. Smokers had significantly improved PFS (log-rank HR=4.867, p=0.027), while patients receiving radiotherapy had significantly decreased PFS (log-rank HR=6.649, p=0.012). A Cox regression model confirmed that both radiotherapy (p=0.022) and performance status (p=0.009) were independent negative predictors of PFS.

CONCLUSIONS

More rigorous PD-L1 TPS stratification did not influence survival outcomes. Smoking history improved PFS, although it was not an independent response predictor, while radiotherapy and performance status independently influenced clinical response. We suggest that further stratification of PD-L1 TPS is not warranted, while performance status and radiotherapy treatment may be additional clinically useful biomarkers of response to pembrolizumab in patients with NSCLC.

First-line nivolumab plus ipilimumab for metastatic non-small cell lung cancer, including patients with ECOG performance status 2 and other special populations: CheckMate 817

BACKGROUND

CheckMate 817, a phase 3B study, evaluated flat-dose nivolumab plus weight-based ipilimumab in patients with metastatic non-small cell lung cancer (NSCLC). Here, in this research, we report on first-line treatment in patients with Eastern Cooperative Oncology Group (ECOG) performance status (PS) 0-1 (cohort A) and special populations (cohort A1: ECOG PS 2; or ECOG PS 0-1 with untreated brain metastases, renal impairment, hepatic impairment, or controlled HIV infection).

METHODS

Cohorts A and A1 received nivolumab 240 mg every 2 weeks plus ipilimumab 1 mg/kg every 6 weeks. The primary endpoint was the incidence of grade 3-4 and grade 5 immune-mediated adverse events (IMAEs; adverse events (AEs) deemed potentially immune-related, occurring <100 days of last dose, and treated with immune-modulating medication (except endocrine events)) and treatment-related select AEs (treatment-related AEs with potential immunological etiology requiring frequent monitoring/intervention, reported between first dose and 30 days after the last dose) in cohort A; efficacy endpoints were secondary/exploratory. In cohort A1, safety/efficacy assessment was exploratory.

RESULTS

The most common grade 3-4 IMAEs were pneumonitis (5.1%), diarrhea/colitis (4.9%), and hepatitis (4.6%) in cohort A (N=391) and diarrhea/colitis (3.5%), hepatitis (3.5%), and rash (3.0%) in cohort A1 (N=198). The most common grade 3-4 treatment-related select AEs were hepatic (5.9%), gastrointestinal (4.9%), and pulmonary (4.6%) events in cohort A and gastrointestinal (4.0%), skin (3.5%), and endocrine (3.0%) events in cohort A1. No grade 5 IMAEs or treatment-related select AEs occurred. Treatment-related deaths occurred in 4 (1.0%) and 3 (1.5%) patients in cohorts A and A1, respectively. Three-year overall survival (OS) rates were 33.7% and 20.5%, respectively.

CONCLUSIONS

Flat-dose nivolumab plus weight-based ipilimumab was associated with manageable safety and durable efficacy in cohort A, consistent with data from phase 3 metastatic NSCLC studies. Special populations of cohort A1 including patients with ECOG PS 2 or ECOG PS 0-1 with untreated brain metastases had manageable treatment-related toxicity and clinically meaningful 3-year OS rate.

TRIAL REGISTRATION NUMBER

NCT02869789.

Prospective, Noninterventional Study of Nivolumab in Real-world Patients With Locally Advanced or Metastatic Non-small Cell Lung Cancer After Prior Chemotherapy (ENLARGE-Lung)

Nivolumab was the first immune checkpoint inhibitor approved for use in advanced non-small cell lung cancer (NSCLC). This noninterventional, prospective cohort study investigates real-world effectiveness of nivolumab in pretreated NSCLC patients in Germany (Enlarge-Lung/CA209-580). Patients with squamous (SQ) or nonsquamous (NSQ) NSCLC previously treated for locally advanced or metastatic (stage IIIB/IV) disease received nivolumab according to the current Summary of Product Characteristics. Overall survival (OS) was the primary endpoint. Of 907 patients enrolled, 660 patients who were followed for at least 12 months across 79 study centers in Germany, were analyzed. Median OS was 11.2 months [95% confidence interval (CI), 9.1-12.9]; outcomes for the 418 patients with NSQ histology [13.1 mo (95% CI, 10.6-15.6)] were more favorable than outcomes for the 242 patients with SQ histology [8.9 mo (95% CI, 6.4-11.3)]. Patients' age, presence of distant or brain metastases, or line of therapy did not affect outcomes; however, patients with poor performance status (ECOG-PS ≥2, n=80) had shorter median OS [4.7 mo (95% CI, 3.1-5.4)]. This study represents one of the largest real-world cohorts providing outcomes of nivolumab in pretreated NSCLC. The results match well with the published evidence from pivotal clinical trials and demonstrate clinical effectiveness of nivolumab in advanced NSCLC.

Therapeutic and Prognostic Implications of Immune-Related Adverse Events in Advanced Non-Small-Cell Lung Cancer

Introduction

PD-(L)1 inhibitors have improved prognosis of non-small-cell lung cancer (NSCLC), but can also cause immune-related adverse events (irAEs) that complicate management.

Methods

We analyzed NSCLC patients receiving PD-(L)1 inhibitors from 2012 to 2020 in a German academic center.

Results

IrAE showed comparable frequencies in stage IV (198/894 or 22%) vs. III (14/45 or 31%, p = 0.15), after anti-PD-(L)1 monotherapy vs. chemoimmunotherapy (139/483 vs. 58/213, p = 0.75), and across treatment lines. In stage IV, irAE occurred after 3.1 months in median, affected multiple organs (median 2) in 27/894 patients and were associated with PD-L1 positivity (25 vs. 14%, p = 0.003), lower neutrophil-to-lymphocyte ratios (29 vs. 17%, p < 0.001 for NLR dichotomized at 5), better ECOG status (26 vs. 18% for 0 vs. 1, p = 0.004), but not related to age, sex, smoking and palliative radiotherapy. Two hundred thirty two irAEs occurred mostly in endocrine glands (4.9%), lungs (4.4%), the musculoskeletal system (4.2%), colon (4.1%), liver (3.7%), and skin (2.6%), while pneumonitis was most frequent with durvalumab following definitive chemoradiation (16% or 7/45, p < 0.01). IrAE severity was grade 1 in 11%, 2 in 41%, 3 in 36%, and 4 in 11% events, while two were lethal (<1%, myocarditis and pneumonitis). Therapy was suspended in 72%, while steroids were initiated in 66% and complemented by other immunosuppressants in 6%, with longest treatment duration for rheumatic events (mean >3 months), and average cumulative prednisone doses >700 mg for all organs, except for skin. Patients developing irAE had longer progression-free (PFS) and overall survival (OS) in multivariable 12/14-week landmark analyses including ECOG status, treatment line, treatment type, PD-L1 TPS, and NLR (median PFS 17 vs. 10 months, HR = 0.68, p = 0.009; median OS 37 vs. 15 months, HR = 0.40, p < 0.001), regardless of grade. OS was longest with skin (95% at 2 years) and shortest with pneumonitis, hepatitis, neurologic, and cardiologic irAE (38, 37, 28, and 0% at 2 years, p < 0.001).

Conclusions

Approximately one-fourth of immunotherapy-treated NSCLC patients develop irAEs, most of which necessitate treatment suspension and steroids. Despite more frequent occurrence with PD-L1 positive tumors, lower NLR, and better ECOG PS, irAEs are independently associated with longer survival, especially when affecting the skin. Lethality is below 1%.