Come to think of it...
From The Lost Media Wiki
I may actually have a copy of it, and by the way, I swear that I am telling the truth. There's a pretty good chance that it's official...That's what I said several months ago. I saw the floppy disk that the game was on before I knew that the port was lost media, and I only saw the label for a brief moment. However, when I looked at the disk recently, it said “The Great Giana Sisters 2.” However, it also said “Super Mario Bros 3” Interesting eh?