platinum 789Keynote-789. KEYNOTE-789 was a randomized, double-blind phase 3 study. 18 It was desned to evaluate the addition of pembrolizumab to platinum-based chemotherapy inKeynote-789. KEYNOTE-789 was a randomized, double-blind phase 3 study. 18 It was desned to evaluate the addition of pembrolizumab to platinum-based chemotherapy in