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Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported. We report 5-year results from the phase III KEYNOTE-042 study (ClinicalTrials.gov identifier: NCT02220894). Eligible patients with locally advanced/metastatic non-small-cell lung cancer (NSCLC) without EGFR/ALK alterations and with programmed death ligand-1 (PD-L1) tumor proportion score (TPS) ≥ 1% received pembrolizumab 200 mg once every 3 weeks for 35 cycles or chemotherapy (carboplatin + paclitaxel or pemetrexed) for 4-6 cycles with optional maintenance pemetrexed. Primary end points were overall survival (OS) in PD-L1 TPS ≥ 50%, ≥ 20%, and ≥ 1% groups. Patients who completed 35 cycles of pembrolizumab with ≥ stable disease could begin second-course pembrolizumab upon progression. One thousand two hundred seventy-four patients were randomly assigned (pembrolizumab, n = 637; chemotherapy, n = 637). Median follow-up time was 61.1 (range, 50.0-76.3) months. OS outcomes favored pembrolizumab ( v chemotherapy) regardless of PD-L1 TPS (hazard ratio [95% CI] for TPS ≥ 50%, 0.68 [0.57 to 0.81]; TPS ≥ 20%, 0.75 [0.64 to 0.87]; TPS ≥ 1%, 0.79 [0.70 to 0.89]), with estimated 5-year OS rates with pembrolizumab of 21.9%, 19.4%, and 16.6%, respectively. No new toxicities were identified. Objective response rate was 84.3% among 102 patients who completed 35 cycles of pembrolizumab and 15.2% among 33 patients who received second-course pembrolizumab. First-line pembrolizumab monotherapy continued to show durable clinical benefit versus chemotherapy after 5 years of follow-up in PD-L1-positive, locally advanced/metastatic NSCLC without EGFR/ALK alterations and remains a standard of care.

Early clinical data indicate that some patients with castration-resistant prostate cancer may benefit from program death ligand-1 (PD-L1) inhibition, especially with enzalutamide. The IMbassador250 trial (no. NCT03016312) enrolled 759 men with metastatic castration-resistant prostate cancer whose disease progressed on abiraterone. The addition of atezolizumab to enzalutamide in an open-label randomized trial did not meet the primary endpoint of improved overall survival in unselected patients (stratified hazard ratio 1.12, 95% confidence interval (0.91, 1.37), P = 0.28), despite an acceptable safety profile. In archival tumor samples, prostate tumors showed comparatively low expression of key immune biomarkers. DNA damage-response alterations, phosphatase and tensin homolog status and PD-L1 expression levels were similar between hormone-sensitive and castration-resistant prostate cancers. In planned biomarker analysis, longer progression-free survival was seen with atezolizumab in patients with high PD-L1 IC2/3, CD8 expression and established immune gene signatures. Exploratory analysis linked progression-free survival in the atezolizumab arm with immune genes such as CXCL9 and TAP1, together with other potentially relevant biomarkers including phosphatase and tensin homolog alterations. Together these data indicate that the expected biology associated with response to immune checkpoint inhibitors is present in prostate cancer, albeit in fewer patients. Careful patient selection may be required for immune checkpoint inhibitors to identify subgroups of patients who may benefit from this treatment approach., (© 2022. The Author(s), under exclusive licence to Springer Nature America, Inc.)