Gandolfini shot a pilot for "Criminal Justice," an adaptation of the 2008 BBC series. Gandolfini played a low-rent New York City attorney.
The 51-year-old star of "The Sopranos" died of a heart attack in June.
HBO Programming President Michael Lombardo told the Television Critics Association on Thursday that he couldn't imagine airing the pilot with Gandolfini since he wouldn't continue with the drama.
"Criminal Justice" was being restructured as a miniseries.
Lombardo says it's difficult to think of recasting Gandolfini's part. He didn't indicate what the drama's future would be.
Gandolfini's final movies, the crime film "Animal Rescue" and the romance "Enough Said," are awaiting release.