The Dragons sit in second place in Pool 2, eight points behind leaders Bath.
Dragons skipper Andrew Coombs also returns to the fold as he sat out the New Year's Day game with the Cardiff Blues due to a knee injury. Full back Dan Evans retains his place and is joined in the back three by Matthew Pewtner, who moves from the left to the right wing to accommodate Prydie.
Ross Wardle steps in alongside Ashley Smith in the centre with Pat Leach on the bench. Jason Tovey gets the nod again from Lyn Jones as fly half and partners Richie Rees at half back.
Jones has made four changes in the pack. Nathan Buck steps in to make his second start of the season in the front row, Coombs returns to partner Rob Sidoli in the second row while the back row is made up of Jevon Groves, Nic Cudd and Toby Faletau.
Bath include former Wales centre Gavin Henson from the start and Dom Day starts at lock. England RBS 6 Nations Squad member Anthony Watson begins at full back.