CHICAGO (AdAge.com) -- With a new global CMO installed at Burger King, the changes are beginning to come. The chain recently dismissed long-time kids' agency Campbell Mithun, and another high-ranking marketing executive has left the company. Meanwhile it continues to battle slumping sales. For the third fiscal quarter ended March 31, same-store sales fell 6% in the U.S. and Canada, capping a year of declines.

Burger King is also losing share to both McDonald's and Wendy's ; its share of hamburger sales fell from 15% in 2008 to 14% in 2009. McDonald's share grew more than a point to 48% and Wendy's grew more than half a point, to 13%. Burger King worked hard to snag the category's No. 2 position, but its hold is becoming tenuous.

At times like these, most industry experts expect an account review, but the fast feeder denies the possibility of breaking with Crispin Porter & Bogusky, which has been its creative agency of record for six years. "[Burger King] and Crispin Porter & Bogusky are and will continue to be strong partners who work together to engage, entertain and attract consumers, bringing the Burger King brand to life in exciting and unexpected ways," a spokeswoman said in a statement. BK CMO Natalia Franco was unavailable for an interview. Crispin referred calls to Burger King.

As for Campbell Mithun's dispatch, the spokeswoman said the eight-year collaboration, "resulted in the development of many successful advertising campaigns for our youth and family market." The Pitch Agency, which has been the youth and family promotions agency since 2008, will expand into youth and family advertising. Effective July 1, the change "further streamlines our marketing efforts to this very important market," the spokeswoman said.

Campbell-Mithun CEO Steve Wehrenberg said the agency was proud of its years with Burger King, a pairing that he said saw "a lot of success," although he was surprised when the relationship ended before the agency had its first meeting with the new executives who made the decision.

Mr. Wehrenberg added that the agency had been unsure about the account's prospects for several years, as restrictions on marketing to kids have limited the scope of the work.

In fact, Crispin's Alex Bogusky noted on his personal blog last week that Burger King has at times considered stopping all of its marketing to kids in a bid to pressure rival McDonald's, which boasts a much larger scale of that market. Mr. Bogusky mused about the possibility of kids' marketing ceasing altogether.

Brian Gies, who was VP-marketing impact and one of the most-visible and highest-ranking marketers under previous CMO Russ Klein, recently left Burger King "to pursue other opportunities." Mr. Gies had been with the company since 1994. His successor is Leo Leon, another company veteran, who, according to his LinkedIn profile, has held marketing positions for BK in Latin America and the Mediterranean. "In his new role, Leo oversees the creative development and implementation of all national advertising, media, merchandising, sponsorship and promotion initiatives for all consumer demographics, including general market, multicultural and parties with kids," the spokeswoman said.

~ ~ ~
Contributing: Rupal Parekh