Johnson & Johnson SARS-CoV-2 vaccine shows promise in clinical trials Many countries have now started to roll out vaccination efforts to contain the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the pathogen that causes the coronavirus disease 2019 (COVID-19). One of the candidate vaccines, the adenovirus serotype 26 (Ad26) vector-based vaccine expressing an optimized SARS-CoV-2 spike (Ad26.COV2.S) or JNJ-78436735, is now in Phase 3 of human trials. Developed by Janssen Vaccines (Johnson & Johnson) and Beth Israel Deaconess Medical Center (BIDMC), the vaccine is a si...