Jcovden (ex COVID-19 Vaccine Janssen) is a vaccine used to prevent the 2019 coronavirus disease (COVID-19) in people aged 18 and over. The vaccine causes the immune system to produce antibodies and specialized white blood cells which act against the virus, thus providing protection against the disease.

It is a monovalent vaccine composed of a recombinant vector based on human adenovirus type 26, unable to replicate, which encodes the complete sequence of the SARS-CoV-2 spike glycoprotein (S) in a stabilized conformation.

 After administration, SARS-CoV-2 S-glycoprotein is transiently expressed, stimulating both neutralizing anti-S antibodies and other functional anti-S specific antibodies, as well as cellular immune responses directed against the S antigen, which contribute to protecting against COVID-19.