OA12.06 First-Line Pembrolizumab or Placebo Combined with Etoposide and Platinum for ES-SCLC: KEYNOTE-604 Long-Term Follow-Up Results

In the phase 3 KEYNOTE-604 study of pembrolizumab + etoposide/platinum (EP) versus placebo + EP as first-line therapy for ES-SCLC (NCT03066778), PFS was significantly improved with pembrolizumab + EP versus placebo + EP (HR, 0.75 [95% CI, 0.61-0.91]; P=0.0023) and although the HR for OS favored pembrolizumab + EP, the significance threshold was not met (HR, 0.80 [95% CI, 0.64-0.98]; P=0.0164). We present updated results with ∼3.5 years of follow-up and outcomes in patients who completed 35 cycles of pembrolizumab.