Premiership champions Exeter will begin their title defence at Gloucester when the 2017-18 season starts on 1 September.
Wasps sign Gloucester's Paul Doran-Jones and fellow prop David Langley from Cambridge, while Tom Bristow exits the club.
Gloucester confirm Carl Fearns will remain with Lyon, despite signing a deal to move to the Premiership this summer.
Edinburgh and London Irish are to meet holders Stade Francais in the Pool stage of next season's European Challenge Cup.
Audio & Video
Gloucester chief executive Stephen Vaughan tells BBC Points West he was disappointed former head coach Laurie Fisher appeared to resign on social media.
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