Story highlights Joan Tarshis tells CNN Cosby assaulted her twice when she was 19

Cosby has repeatedly said allegations against him of sexual assault are untrue

She says she kept quiet for years because she didn't think people would believe her

Accusations from other women have resurfaced this year

A woman told CNN on Monday that Bill Cosby sexually assaulted her 45 years ago, when she was a teenager.

Joan Tarshis, a journalist and publicist, said she met Cosby in 1969 in Los Angeles when she was invited to have lunch by some friends of his. They saw each other again and she visited him on the set of "The Bill Cosby Show."

On one occasion, Cosby invited Tarshis, who had been writing monologues for the comedian Godfrey Cambridge, back to his bungalow to work on some comedy routines.

"I thought, 'That's cool, getting to work with Bill Cosby on jokes,'" Tarshis told CNN's Don Lemon.

She said Cosby made her a drink that he knew she liked, a Bloody Mary topped with beer known as a Red Eye.

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Tarshis, who was 19 at the time, said that shortly after drinking the Red Eye, she "passed out."

"I woke up or came to very groggily with him removing my underwear," she said.

'You'll never get me again'

Tarshis said that she tried to deter Cosby by saying she had an infection that his wife might catch, but that he then made her have oral sex with him.

She said she left, vowing never to see him again.

But he subsequently called her home in New York and invited her to watch him perform at the Theater at Westbury. Tarshis said she didn't know how to back out of it because she hadn't told her mother, a big fan of Cosby, what had happened.

After accepting drinks at Cosby's hotel and in the limousine, Tarshis said she felt "very, very, very drugged" at the theater and asked the chauffeur to take her back to the car.

She said she passed out in the car and when she woke up, it was the next morning and she was naked in bed with Cosby.

"I didn't say what I wanted to say" to Cosby at the time, Tarshis told CNN's Lemon. "What I said to myself was, 'You old expletive, you finally got me. You'll never get me again.'"

Repeated denials

Tarshis joins a group of women who have accused Cosby, 77, of sexual assault -- claims the comedian denies.

"Over the last several weeks, decade-old, discredited allegations against Mr. Cosby have resurfaced," John P. Schmitt, the lawyer, said in a statement Sunday. "The fact that they are being repeated does not make them true. Mr. Cosby does not intend to dignify these allegations with any comment."

Cosby has repeatedly said the allegations are untrue, and he has never been prosecuted.

He did settle a case in 2006, filed by Andrea Constand, a staffer for Temple University's women's basketball team, who accused him of drugging and molesting her at his suburban Philadelphia home.

Constand's lawyers said they found 13 Jane Doe witnesses with similar stories, but no witnesses were ever called. The terms of the settlement have never been disclosed.

Cosby and Constand's lawyers said in Monday that Schmitt's earlier statement "was not intended to refer in any way to Andrea Constand."

"As previously reported, differences between Mr. Cosby and Ms. Constand were resolved to the mutual satisfaction of Mr. Cosby and Ms. Constand years ago," the lawyers said in a joint statement. "Neither Mr. Cosby nor Ms. Constand intends to comment further on the matter."

Silence in radio interview

Since 2005, a handful of women have made the claims. This year, the accusations resurfaced, and earlier this month, a seemingly harmless post on Cosby's Twitter account turned them into a social media storm

In its wake, one of his accusers, Barbara Bowman, turned to the public once more with an article in the Washington Post and interviews with CNN.

Bowman claims she was drugged then raped, though she said she never saw drugs. "I woke up out of a very confused state not in my clothes," she said.

Bowman said she knew her body had been touched without her permission. This occurred several times in the course of their contact, she said.

On Saturday, NPR broadcast an awkward interview with Cosby in which he didn't utter a word when repeatedly asked about the claims about him.

NPR host Scott Simon filled the airtime by saying Cosby was just "shaking his head no."

"There will be no further statement from Mr. Cosby or any of his representatives," Cosby's lawyer said Sunday.

'Who's going to believe me?'

Tarshis told CNN she had kept quiet about what happened to her because she felt "the guilt and the shame of the victim" -- and because she didn't think anyone would take her word for it.

"Who's going to believe me?" she said on CNN. "Bill Cosby, the all-American dad, the all-American husband, 'Mr. Jell-O' that everybody loves. Who would believe me? They'd probably think I was out to get something."

But she said she decided to speak up now in order to support the other women and give them "some more credibility."

"I really have nothing to gain by doing this," she said.

Before appearing on CNN, Tarshis made the allegations against Cosby in an account published on Hollywood Elsewhere on Sunday.

On Monday, the Village Voice drew attention to a track on an album by Cosby from 1969 in which he jokes about a drug he heard about when he was a boy, known as "Spanish Fly," that would make girls go crazy when put into their drink.

In the routine, he goes on to talk about visiting Spain as an adult with another actor and wanting to get hold of the drug.

Village Voice film editor Alan Scherstuhl said even as a child this statement from Cosby puzzled him.