Mr. Tambor, whose representatives did not immediately respond to phone calls and emails seeking comment on Sunday, has denied both women’s allegations. He initially referred to Ms. Barnes as “a former disgruntled assistant of mine” and told Deadline that he was “appalled and distressed by this baseless allegation.” And after Ms. Lysette’s statement, he told The Hollywood Reporter that he was upset to “find myself accused of behavior that any civilized person would condemn unreservedly.”

“I know I haven’t always been the easiest person to work with,” he said. “I can be volatile and ill-tempered, and too often I express my opinions harshly and without tact. But I have never been a predator — ever.”

In response to the flood of sexual harassment and assault allegations against prominent men in the past few weeks — from Harvey Weinstein, Kevin Spacey and Louis C.K. to the Senate candidate Roy S. Moore and Senator Al Franken — the executives behind many projects have been forced to decide what to do when a star becomes toxic.

In some cases, these projects have been canceled. Netflix, for example, suspended production on “House of Cards” after its star, Mr. Spacey, was accused of making a sexual advance on the actor Anthony Rapp when Mr. Rapp was 14. (Allegations by many other men have been reported since.) And when a New York Times investigation revealed multiple allegations of sexual misconduct by the comedian Louis C.K., a distributor canceled the premiere of his movie “I Love You, Daddy,” and FX and other networks broke ties with him.

But in her statement, Ms. Lysette urged Amazon not to cancel “Transparent,” but instead to “remove the problem and let the show go on.” The series has been a leader in affirming and employing transgender people — both she and Ms. Barnes are transgender women — and they should not be punished for Mr. Tambor’s actions, she said.

Mr. Tambor, 73, is also known for his role in the TV series “Arrested Development,” which originally ran from 2003 to 2006 but has been revived twice since. Netflix recently finished shooting the fifth season, and it was unclear on Sunday how it would respond.