Toulouse got the full five points from their trip to Zebre as the game was brought to an end after just 64 minutes due to fog.
The visitors had already scored five tries and were leading 36-6 when referee Ian Davies stopped the game due to poor visibility.
A statement from EPCR read: "The referee's decision was taken after consultation with the captains and coaching staff of both clubs.
"Under the Tournament Rules 2016/17, if a game is stopped or abandoned after 60 minutes, the result stands. Toulouse are therefore awarded five match points as they scored five tries."
This is Toulouse's first triumph in the Champions Cup this term with Arthur Bonneval crossing twice while Gael Fickou, Joe Tekori and Yoann Huget also scored.
Toulouse, now with eight points from three matches, move up a place to second in the group, while Zebre are bottom with no points on the board.