Born a micro preemie at under 26 weeks, little Alistair was also at very high risk for severe disease from other germs, including respiratory syncytial virus (RSV). Now the development of these monoclonal antibodies “is the third significant inflection point event,” he says. Finally, scientists had unlocked the code to allow them to begin developing a highly potent monoclonal antibody. By the end of the summer of 2023, just in time for the fall RSV season, the FDA had approved one preventive monoclonal antibody and two vaccines against RSV. AstraZeneca partnered with Sanofi to make and market the highly effective monoclonal antibody nirsevimab for all infants.