Biotechnology has figured prominently in recent Medicare coverage and payment policies. Biotech treatments push policy boundaries for several reasons: They attract strong patient demand; they often treat rare or life-threatening diseases; they may have uncertain evidence of health benefits; and they are often costly. This paper considers case studies of Medicare coverage for off-label uses of biotech cancer drugs and payments for anemia biopharmaceuticals. The cases suggest Medicare's ongoing challenge to balance access considerations, the role and strength of evidence, and cost consequences of new treatments.