Bloomsbury Publishing saw annual profits more than triple last year thanks to strong Harry Potter sales, and said a strong pipeline of new titles would see it through the post-wizard era.

The publisher said this morning that pre-tax profits jumped to £17.86m in 2007, from £5.2m in 2006. Revenues doubled to £150.2m. The news sent its shares climbing 2.5p to 167.5p in early trading, a 1.5% gain.

Both adult and children's titles put in record-breaking performances, with strong sales of Khaled Hosseini's The Kite Runner and A Thousand Splendid Suns, and of Harry Potter and the Deathly Hallows.

Current trading has been boosted by the launch of Jonathan Littell's controversial Die Wohlgesinnten, where hardcover sales have breached 100,000 copies.

"We are now well positioned for the post Harry Potter era," said chief executive Nigel Newton. "We have reduced overhead costs, are successfully developing new business areas in specialist publishing, and have a strong pipeline of titles."

Bloomsbury authors with new books coming include David Guterson, author of Snow Falling on Cedars, Margaret Atwood, Justin Cartwright, Anne Michaels, who wrote Fugitive Pieces, and Ben Schott.

Bloomsbury has been working hard to plug the gap left after the release last year of the boy wizard's final adventure. Newton, who founded company 21 years ago, now has to demonstrate he can maintain growth even after the runaway success of the Potter series has come to an end.

Newton described 2007 as a "landmark year" for the group, when the roles of chairman and chief executive were split.

In an effort to find new revenue streams, Bloomsbury has struck a deal to publish Reed's Nautical Almanac online and yesterday acquired Featherstone Education, an educational publisher. It has reduced the number of new adult titles to devote more time and energy to ensure that each title generates more revenue.