alxsav, I got a roll of 150 m of Agfa AVIPHOT PAN 200 PE1, and 400 and 80 for 35 mm ( Agfa test).
Like the Agfa AVIPHOT 200 and 400 are black dorsal layer is easily cleaned in solution.
Agfa recommends that before developer wash the film to remove this layer will contaminate developer.
I used a solution of sodium carbonate 10 g / l, then washed film.
It worked well in Kodak D 96. Fog is small (0.06).
:AVIPHOT PAN 200 documentation
:Aviphot Pan 200 PE1 is a panchromatic negative film, coated onto a transparent polyester base
providing excellent dimensional stability. Thickness of the polyester base: 0.10 mm (.004).
:Aviphot Pan 200 PE0 is a similar film coated onto a 0.06 mm (.0025) polyester base.
:Aviphot Pan 200 PE0 AR, coated on a 0.06 mm (.0025) polyester base is designed for LED
exposure through the back.
May be that your film is Aviphot Pan 200 PE0 AR?
http://www.flickr.com/photos/21121448@N06/5713454489/
George