Launchbury had been out since September due to knee and neck problems, but the lock helped Dai Young’s struggling side stop the rot at the Ricoh Arena.
Wasps had lost nine of their previous 10 matches and had secured just one victory since September, yet they moved up to sixth spot by ending Northampton’s run of four consecutive wins across all competitions.
Josh Bassett took a pass from Willie le Roux to put Wasps in front in the corner after strong carries from Brad Shields and Nizaam Carr, and Juan de Jongh raced onto his own grubber kick to add a second try, which Ahsee Tuala probably ought to have prevented.
Cobus Reinach laid on a first Saints try for Fraser Dingwall and Dan Biggar’s third penalty just before half-time reduced the deficit to 17-16.
The outstanding Thomas Young had a try ruled out, but Taqele Naiyaravoro gifted Le Roux a score with an ill-advised attempted offload after Saints had got themselves out of the in-goal area with a couple of risky passes.
Lima Sopoaga converted and capped an excellent display of kicking by adding a penalty to take his tally to 12 points as Wasps lifted the gloom in Coventry.
FULL-TIME | ?Wasps 27-16 Northampton Saints? pic.twitter.com/3QFvkrTqbo
— Wasps Rugby (@WaspsRugby) January 6, 2019
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