Richard D. Parsons, a longtime media executive who less than a month ago was named the interim chairman of CBS to help stabilize the company, said on Sunday that he was stepping down because of illness.
Forced again to reshuffle its leadership ranks, the CBS Corporation named as his replacement Strauss Zelnick, the head of the video game publisher Take-Two Interactive Software. Mr. Zelnick, who is widely respected within the media industry, was appointed to the CBS board in early September. He had led the music publisher BMG Entertainment and had served as president of 20th Century Fox.
The shake-up complicates an already difficult time for CBS, which has spent most of the past year fighting scandal on multiple fronts. Several accusations of sexual misconduct were made against Leslie Moonves, its chief executive, as well against a longtime leader of its news division. Separately, a contentious legal showdown with its controlling shareholder threatened to upend the company’s management.
As CBS worked to resolve the disputes, Mr. Parsons was instrumental in negotiating the departure of Mr. Moonves. He also advised on appointing Joseph Ianniello, the chief operating officer, as acting chief executive, and helped install six new directors to lead the company out of trouble, according to several people close to the board who spoke on the condition of anonymity. The lawsuit was dissolved as part of Mr. Moonves’s exit agreement.
Several years ago, Mr. Parsons was found to have a rare form of blood cancer known as multiple myeloma. His disease went into remission after he underwent a stem cell transplant. In a statement released by CBS, he said, “Unfortunately, unanticipated complications have created additional new challenges, and my doctors have advised that cutting back on my current commitments is essential to my overall recovery.”
Mr. Parsons has a reputation as a trustworthy dealmaker, one who could settle the most rancorous of disputes. He untangled what is considered one of the worst mergers in corporate history, AOL-Time Warner, and he helped stabilize Citigroup after the 2008 recession. In 2014, he was called in to help rehabilitate the Los Angeles Clippers of the National Basketball Association.
Under Mr. Parsons’s leadership, the revamped CBS board had already started the search for a chief executive as it evaluated who could best help the company navigate what has become a tough landscape for media businesses. Silicon Valley continues to steal ad dollars and eyeballs away from traditional television outlets, and entertainment companies have had to find new ways to maintain relevance with younger audiences.
In the case of CBS, it has played up gains in its streaming effort, CBS All Access, which has over 2.5 million paying subscribers and is on pace to hit four million by next year, according to the company. The premium cable network Showtime, part of CBS, has also made strides in streaming and expects to sign up a similar number of customers in the same period. Together, the streaming businesses account for over $500 million in annual revenue, a business line that didn’t exist just years ago.
Mr. Ianniello, who is a candidate to become the permanent chief executive, has already made several key executive appointments in the two months he has been on the job.
He appointed David Nevins the chief executive of Showtime, to head up all programming as chief creative officer, a newly created role. He also named a head finance executive, a new head of human resources and a chief communications officer.
The board is still awaiting the outcome of an investigation into the claims of sexual harassment made against Mr. Moonves and Jeff Fager, the head of CBS’s most lucrative news program, “60 Minutes,” and a former leader of its news division. Both have denied the allegations.
The CBS board hired Nancy Kestenbaum of Covington & Burling and Mary Jo White of Debevoise & Plimpton to conduct its internal investigation into the accusations and the overall culture at the company.
Ms. White led the Securities and Exchange Commission during the Obama administration and was previously the United States attorney for the Southern District of New York. Ms. Kestenbaum was also a federal prosecutor with the same district.