42P Pembrolizumab vs chemotherapy in Chinese patients with non-small cell lung cancer (NSCLC) and PD-L1 TPS ≥1%: 5-year update from KEYNOTE-042

After 4 y of follow-up in patients (pts) enrolled in China in the phase III KEYNOTE-042 study, pembrolizumab (pembro) improved OS vs chemotherapy (chemo) in pts with previously untreated advanced or metastatic NSCLC without EGFR/ALK alterations in the PD-L1 tumor proportion score (TPS) ≥50% (HR, 0.66; 95% CI, 0.45–0.95), ≥20% (0.68, 0.49–0.93), and ≥1% (0.67, 0.51–0.89) groups. We report results after 16 mo of additional follow-up. Eligible pts were randomized 1:1 to receive pembro 200 mg Q3W for ≤35 cycles or carboplatin + paclitaxel or pemetrexed with optional pemetrexed maintenance (nonsquamous only). Primary endpoints were OS in pts with PD-L1 TPS ≥50%, ≥20%, and ≥1%. No alpha was assigned to this exploratory analysis of pts enrolled in China in KEYNOTE-042 global (NCT02220894) and China extension (NCT03850444) studies. Of 262 pts enrolled in China, 128 were randomized to pembro and 134 to chemo. Median time from randomization to database cutoff (Sep 12, 2022) was 63.7 (range, 56.3–72.6) mo. Pembro prolonged OS vs chemo in pts with PD-L1 TPS ≥50% (HR 0.65, 95% CI 0.45–0.93), ≥20% (0.67, 0.49–0.91), and ≥1% (0.66, 0.51–0.87). 5-y OS rates were ~2 fold higher with pembro vs chemo across all 3 PD-L1 TPS groups (table). Grade 3–5 treatment-related AEs occurred in 19.5% of pts in the pembro arm and 68.8% in the chemo arm. Of 22 pts who completed 35 cycles of pembro, ORR was 81.8% (95% CI, 59.7%–94.8%) and 3-y OS rate after completion of 35 cycles (~5 y after randomization) was 56.6%. At data cutoff, 80 pts in the pembro arm and 79 in the chemo arm had begun subsequent therapy; 5 pts began second-course pembro. Similar to the global KEYNOTE-042 study, after 5 y of follow-up, pembro continued to demonstrate improved OS vs chemo with manageable safety in Chinese pts with previously untreated advanced or metastatic NSCLC without EGFR/ALK alterations with PDL1 TPS ≥1%. These data further support pembro monotherapy as a standard of care for these pts.