Wasps have signed scrum-half Sam Wolstenholme from Yorkshire Carnegie, but have cancelled a deal for prop Mike Daniels after he failed a medical.
Wolstenholme, 20, joins after making 23 appearances for the Leeds-based Championship side.
The signing of Daniels, 26, from Championship side Nottingham was initially announced in February.
The club has also announced that fly-half Jacob Umaga has been promoted to the first team from their academy.
The 20-year-old is the nephew of former All Blacks captain Tana Umaga and has scored four tries in seven first-team appearances.