Andrew Lloyd Webber said he has not yet signed up to do another series with ITV after the final of his last show pulled in only half the audience which previous finals on the BBC attracted.
The composer switched from the BBC earlier this year to make Superstar - which saw singer Ben Forster chosen to play the son of God in an arena tour of the musical Jesus Christ Superstar.
Speaking at the GQ Men of the Year Awards, Lord Lloyd-Webber said he was going to be concentrating on bringing his latest musical, about Stephen Ward, one of the key figures in the Profumo affair, to the stage.
He said: "That could be two years off, but what I can say is I'm in discussions to do a special with ITV after Superstar."
An average of 3.3 million watched the 75-minute Superstar final compared with the 7.2 million who watched the final of his I'd Do Anything show on BBC One and the six million who watched Over The Rainbow.
Forster, a 31-year-old stage school graduate, will join the cast which includes comic Tim Minchin as Judas Iscariot, DJ Chris Moyles as King Herod and Melanie C as Mary Magdalene when it goes on tour in September.