According to the Database of 365Chess, the English Wing Gambit has not been tried by a grandmaster in a rated game.
Although there might not be a clear refutation, the gambit seems to be somewhat dubious. Compared with most gambits, white does not obtain a quick development. Compared with the Sicilian Wing Gambit, white acquires less control in the center. Compared with the Benko Gambit, black's central pawns are still flexible (which was already pointed out by Brian Towers).
After 1.c4 c5 2.b4, the most principled reply is to accept the gambit by 2....cxb4. Now, white has two logical continuations: 3.a3 (Benko style) and 3.d4 (trying to occupy the center). Regardless of white's third move, black can play 3....e6 and 4....d5, after which white doesn't have enough compensation.
Instead of accepting the gambit, black is also more than fine after 2....Nf6, as he will regain the pawn after 3.bxc5 e5.
1.c4 c5 2.b4 cxb4 (2...Nf6 3.bxc5 e5) 3.d4 (3.a3 e6) e6 4.e4 d5