The rights of Peter Pan were left to Great Ormond Street Children's Hospital by the original author JM Barrie and a spokesman for the hospital, which will be selling the book, said: "It's gone very well, it's flying off the shelves."
The book is set 20 years after the original story and Peter Pan's friend Wendy now has children of her own and the Lost Boys have all grown up.
The publishers of Peter Pan in Scarlet tried to keep its details secret but had to launch an investigation back in August after an American paper printed a summary of the book's plot.
Peter Pan in Scarlet is being published in 30 different countries in 34 languages.
