Bill Cosby has canceled an appearance on “The Late Show with David Letterman” scheduled for Wednesday as mainstream media outlets heighten the scrutiny of longstanding allegations of sexual assault leveled against the comedian.

A rep for Cosby did not respond to a request for comment. CBS would not comment on the change in “Late Show’s” Wednesday guest lineup.

Cosby’s retreat from the national TV spotlight comes after an Arizona woman, Barbara Bowman, revived allegations that he drugged and raped her in the mid-1980s when she was an aspiring actress who met him in New York City. Cosby and his reps in the past have strongly denied the allegations from Bowman and other women.

On Thursday, the Washington Post published a lengthy column by Bowman that recounted multiple incidents of sexual assault and her struggle to have her claim believed. At the time of the incidents, Cosby was the star and producer of the nation’s top-rated TV series, the NBC sitcom “The Cosby Show.”

Bowman has made several prominent media appearances in recent days, including an interview with CNN. Comedian Hannibal Buress also brought the spotlight to the decades-old allegations last month when he unabashedly called Cosby a rapist as part of his standup routine that mocked Cosby’s habit in recent years of decrying what he sees as coarse aspects of African-American pop culture. A video of Buress’ performance in Philadelphia went viral, which helped spark a fresh round of media attention on the rape allegations.

The new focus on old allegations seems likely to derail the prospects for Cosby mounting a sitcom comeback with NBC. The network and Sony Pictures TV have a half-hour comedy in development for the comedian that reunites him with Tom Werner, one of the producers of the 1980s series.

As the project came together earlier this year, several studios and writers fought to land the show, given Cosby’s stature as a TV star. The untitled project settled with writers Mike O’Malley and Mike Sikowitz. According to NBC, the project remains in the early stages of development.

Bowman is not the first to accuse Cosby of sexual misdeeds. In 2006, according to the Associated Press, Cosby settled a civil suit with another woman who accused him of sexual assault and claimed in her legal filing that 13 more victims were ready to come forward, one of which was Bowman.

The groundswell of rape allegations has already cast a pall on the 77-year-old entertainer’s status as one of the nation’s most beloved comedians, one who is known for his gentle humor about parenting and family life.

The events of the past few weeks also underscore how quickly scandals can turn into all-encompassing crises for celebrities. Just last week, Cosby appeared at Carnegie Hall as part of the New York Comedy Festival, and he has made other recent media appearances in which he was lauded as an elder statesman.