Project Vitality was a Federation and Section 31 joint project with the sole purpose of creating "super-soldiers".
The project enabled scientists to use an updated DNA Augmentation process to genetically engineer subjects to give them heightened abilities, making them stronger and faster than normal.
The project was shut down when two of the first three subjects died from neural breakdown. The only successful subject of the project was David Gadley.
With the failure of the augmentation process on multiple subjects, the project lost all funding and backing from the Federation and David Gadley decided to enlist in Starfleet Academy.
Despite not getting the "army of soldiers" that they wanted out of the project, Admiral Quinn believed that the one successful subject was worth backing.
Admiral Quinn proposed the idea of giving David Gadley the command of a new prototype starship and an elite squad to be the Federation's "secret weapon". A ship and crew focused on Special Tactics and Reconnaissance.
The Federation officials who knew about the project agreed to revive it for this new "second phase" once the subject completed training at Starfleet Academy.
David Gadley completed his Starfleet training and was given command of the prototype starship U.S.S. Nexus.