That is quite an annoying opening! I have never played against it. Presumably this is a really early prophylactic move to avoid Bb4.
My advice would be to try and steer into your normal preferred opening if it does not involve Bb4. c6 moves towards a standard Slav/semi-Slav setup and seems to do quite well in the database games.
The main problem with prophylactic moves is that they are not developing moves, so if they are made too early they pass the initiative to the other player. Get on with your development.
Hey whats a good defense against the prie attack and if you don't know what it is it's the newes't opening invented by eric prie in 2004 and it's starting to become popular.
The opening is 1.d4/d5 2.a3!?