Newcastle Falcons will sign back-rower Ryan Burrows from Championship side Yorkshire Carnegie at the end of the season.
Joe Simmonds kicks 11 points in his first Premiership start to help Exeter move into second with victory over Newcastle.
Newcastle Falcons are to sign winger DTH van der Merwe for the 2017-18 season once his Scarlets deal expires.
Wasps sign winger Marcus Watson and prop Ben Harris from Newcastle, plus Nottingham hooker Antonio Harris, for 2017-18.
Audio & Video
Near the halfway stage of the 2016-17 season, BBC Sport's Jeremy Guscott assesses the sides vying to be Premiership champions.
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