A scheduled appearance by comedian Bill Cosby on David Letterman’s late night CBS talk show has been cancelled. Cosby was meant to appear on Wednesday night’s edition of the show, but CBS announced on Friday that he was to be replaced by regular stand in Regis Philbin.

Bill CosbyComedian Bill Cosby

The show declined to reveal whether the 77 year old had decided to cancel his appearance himself or if the show had made the decision to replace him. A spokeswoman for the show, Kim Izzo-Emmet, told the New York Times, “We can’t comment on the booking process.”

It’s the second time in a fortnight that a guest appearance by Cosby has been cancelled. On October 30th, a scheduled appearance by the comedian on the Queen Latifah daytime talk show was cancelled reportedly at Cosby’s request. 

More: Bill Cosby's New NBC Show May Be Debuting As Soon As Next Summer

Cosby had been slated to return to TV soon, starring in a new multigenerational sitcom for NBC. However there’s no word yet if the series will still go ahead with Cosby, but it is said to not yet have a script.