What do systematic reviews say?

Pembrolizumab vs chemotherapy alone

Pembrolizumab showed no clear difference in treatment‐related mortality compared with chemotherapy (low certainty).

• Pembrolizumab monotherapy versus chemotherapy for treatment of advanced urothelial carcinoma with disease progression… 2018 · Cochrane Headline outcomes only
  RR 0.96 [0.24, 3.79]
  1 study · 521 participants
  Low