Three weeks after it emerged that Mervyn Peake's wife had written a fourth book in her husband's acclaimed Gormenghast trilogy, Random House has seen off stiff competition from other publishers to acquire rights in the novel.

Peake died from Parkinson's in 1968, leaving behind a page-and-a-half of notes about his plans for Titus Awakes, a fourth book in his classic fantasy series. His wife, Maeve Gilmore, wrote the novel, but it had been hidden in a south London attic since she died in 1983. The couple's granddaughter, Christian, recently discovered it while the family was clearing out the loft.

Three publishers expressed interest in publishing the book, but Random House imprint Vintage Classics triumphed, paying a "significant" sum to acquire rights in Titus Awakes. The novel opens as the 77th Earl of Groan Titus leaves Gormenghast, and follows his search for a final home. Vintage will publish the book in July 2011, on the centenary of Peake's birth, when it will also release a new edition of the Gormenghast trilogy with previously unseen illustrations by the author.

Peake's son Sebastian Peake described Titus Awakes as "an eloquent finale" to his father's Titus books, and said that the whole Peake family was "overjoyed" that Vintage would be publishing it. Acquiring editor Laura Hassan said the novel was "a remarkable book in its own right, but there is the added interest for Gormenghast fans of how Titus's story is resolved".