This study is being done to compare survival using pembrolizumab (SCH 900475, MK-3475) or standard chemotherapy for participants with advanced melanoma (MEL) who have progressed after prior therapy. Participants were initially randomized to receive either low dose pembrolizumab, higher dose pembrolizumab or Investigator-choice chemotherapy (ICC). The randomization to either pembrolizumab or Investigator choice chemotherapy was conducted in an open-label fashion.