Book excerpt: This book is the first to tell the extraordinary yet unheralded history of monoclonal antibodies, or Mabs. Though unfamiliar to most nonscientists, these microscopic protein molecules are everywhere, quietly shaping our lives and healthcare. They have radically changed understandings of the pathways of disease, enabling faster, cheaper, and more accurate clinical diagnostic testing. And they lie at the heart of the development of genetically engineered drugs such as interferon and blockbuster personalized therapies such as Herceptin. Lara V. Marks recounts the risks and opposition that a daring handful of individuals faced while discovering and developing Mabs, and she addresses the related scientific, medical, technological, business, and social challenges that arose. She offers a saga of entrepreneurs who ultimately changed the healthcare landscape and brought untold relief to millions of patients. Even so, controversies over Mabs remain, which the author explores through the current debates on their cost-effectiveness.