The 'Copacabana' singer explained that he was very sad to see intimate details of Spears's private life reported in the media following her divorce from Kevin Federline.
"When we started writing, it was when paparazzi were driving her crazy. She couldn't live a life," Manilow told Parade. "[Spears] was the epitome of the price of fame."
Manilow also hinted that his music will be featured on an upcoming episode of Glee, saying: "[Glee co-creator] Ryan [Murphy] sent me an email saying, 'This year, I'm getting your stuff on our show'. But who knows?"
The musician's current LP 15 Minutes reached the top ten of the US album charts upon its release in June.
Manilow confessed earlier this year that he prays for young celebrities like Justin Bieber.
> Barry Manilow remembers Elizabeth Taylor
Watch Barry Manilow perform the album's title track '15 Minutes' below: