By Jennifer Maloney

Anheuser-Busch InBev SA has begun a search for a chief executive to succeed longtime CEO Carlos Brito, who is expected to move next year to a role on the beer giant's board, according to people familiar with the matter.

Mr. Brito, 60 years old, has led the world's biggest brewer for more than a decade, overseeing the integration of U.S. brewer Anheuser-Busch with the Belgian-Brazilian conglomerate InBev and more recently the 2016 takeover of rival SABMiller.

In recent years, Mr. Brito has faced a slump in beer consumption in the U.S. and other key markets and the company has focused on paying down its debt load, which topped $100 billion after the SABMiller deal. AB InBev halved its dividend in 2018 and spun off its Asian assets in a public offering in 2019.

Before the pandemic struck, the company slashed its financial projections, citing weakness in the U.S. and China. Sales of Bud and Bud Light have lost ground as Americans abandoned mainstream lagers in favor of craft beers, spirits and hard seltzers.

The company in July reported a sharp drop in second-quarter sales and took a $2.5 billion write-down on its business in South Africa. However, Mr. Brito said sales volumes were improving rapidly as restaurants and other businesses reopened after being forced to close amid the pandemic.

The leading internal candidate to replace Mr. Brito is Michel Doukeris, a fellow Brazilian and head of the company's U.S. business, the people familiar with the matter said. The search also includes external candidates, the people said.

The Financial Times earlier reported on the company's CEO succession planning.

Mr. Doukeris previously headed AB InBev's Asia business and ran its soft-drinks business in part of Latin America. He has operational experience in three of the company's top revenue-generating markets: the U.S., China and Mexico.

AB InBev's board is dominated by a small group of Belgian and Brazilian families who together own a majority of the company's shares. The current chairman, former Altria Group Inc. CEO Marty Barrington, is an independent board member.

The board last year changed the company's charter to allow a nonindependent board member to become chairman, according to people familiar with the matter. That opens the door for a representative of the controlling Brazilian and Belgian shareholders -- such as Mr. Brito -- to be nominated as chairman.

The company's American depositary receipts have notched a total shareholder return of 34% over the past 10 years as of Friday's close, compared with a roughly 280% total return for the S&P 500 index. The ADRs, which trade under the symbol BUD, were down 4% Tuesday afternoon.

Write to Jennifer Maloney at jennifer.maloney@wsj.com