In the larger picture, the fight against HIV has been a triumph of modern medicine. A patient diagnosed with HIV in the 1980s had a remaining life expectancy of 1 to 2 years. In 2023, they can expect to live another half century. But so far, an HIV vaccine has remained elusive. In the newest phase III failure, Janssen Pharmaceutical Cos. of Johnson & Johnson closed down its Mosaico trial more than a year ahead of schedule, following a data and safety monitoring board’s (DSMB) report saying the study was not expected to hit its primary endpoint.