Matt Fraction's final full issues of "FF" and "Fantastic Four" will be #11 and #12, respectively.

Matt Fraction will step away from writing duties on both "Fantastic Four" and "FF," Marvel senior vice president of publishing Tom Brevoort has exclusively confirmed to CBR News.

Fraction informed CBR that his last solely written issue of "Fantastic Four" will be #12 (solicited for September), and his last full "FF" will be issue #11 (expected later this month), the next respective issues of each title to be released. [Update: Christopher Selba is listed as a co-writer on the newly released "Fantastic Four" #11, as noticed by Bleeding Cool.] Brevoort, the editor on both books, cited the changes the upcoming "Inhumanity" story and resulting "Inhuman" ongoing series have brought to Fraction's schedule.

"The demands of 'Inhumanity' on Matt's time increased to the point where something had to give, and that something turned out to be 'Fantastic Four' and 'FF,'" Brevoort said. "So Matt outlined the balance of the story he was going to be telling in those books, much as he'd done for 'Fear Itself: The Fearless' a while back, and we've brought in Karl Kesel on 'Fantastic Four' and Lee Allred on 'FF' to execute those plans and to make them their own.

Kesel has an established history with "Fantastic Four," having written the book on a couple of occasions, including a four-issue 2002 arc illustrated by the book's current artist, Mark Bagley. Kesel also inked the series during Mark Waid and Mike Wieringo's acclaimed run from 2002 to 2005.

Lee Allred is a science-fiction writer and the brother of "FF" artist Mike Allred. The two previously collaborated on Mike Allred's 2005 issue of DC's "Solo."

"Matt will continue to be credited on both titles for the duration of the storyline, as he's contributed to each issue in a material way, but the heavy lifting is going to be done by Karl and Lee respectively," Brevoort told CBR.

Fraction had been solicited as the sole writer for both "Fantastic Four" and "FF" through October's issues #13 of both titles. The current storyline in both books are scheduled to wrap with their respective #16 issues.

Staff Writer Dave Richards contributed to this article.