David Baltimore, Nobel Prize-winning molecular biologist renowned for his discovery of reverse transcriptase and groundbreaking contributions to cancer and viral research, died at age 87. Baltimore’s work transformed molecular biology by demonstrating that RNA can be reverse-transcribed into DNA, challenging central dogma concepts and accelerating HIV research. He played pivotal roles in academic leadership and scientific policy, influencing biotechnology and medicine extensively. His passing marks the loss of a foundational figure in molecular and biopharmaceutical sciences.