A 25-year-old model filed a lawsuit against disgraced US comedian Bill Cosby alleging he sexually assaulted her at the Playboy Mansion in 2008.

According to the civil complaint by Chloe Goins, Cosby spiked her drink during a party at the famed mansion and she woke up naked in a bed to find him licking her toes and masturbating.

"Goins awoke to find that her breasts were wet and sticky, as if someone had been licking them, and Bill Cosby was biting one of her toes as he crouched at the end of the bed," the suit alleges.

It adds that when Cosby realized she was conscious, he quickly pulled up his pants and left the room.

Goins, who was 18 at the time of the alleged crime, is among some 50 women who claim that Cosby, over a period spanning four decades, drugged them and then sexually assaulted or raped them.

The statute of limitations prevents most of the women from taking legal action. In Goins's case, the statute runs out in May.

"Today marks a critical step in empowering women to address the rape culture that has become so prevalent in the entertainment industry and in the American conversation," said Goins's attorney Spencer Kuvin, who is seeking at least $75,000 in damages.

"We are confident that when all the facts come out, Mr. Cosby will have to answer for his actions to not only my client, but all the women he has devastated."

Cosby could also face criminal charges if prosecutors who are reviewing a police probe into Goins's allegations decide to pursue the case.

Last December, prosecutors declined to file charges over sexual assault allegations brought by Judy Huth, who claims Cosby also assaulted her at the Playboy Mansion in 1974 when she was 15 years old. Officials said the statute of limitations had expired.

Huth went ahead and filed a civil lawsuit and Cosby is due to give sworn testimony in the case on Friday.

More than 30 women who have accused Cosby of sexual assault have come forward in recent months recounting their stories in detail.

Twenty seven of them are due to appear on NBC News on Friday to tell their stories.

Cosby's lawyers have repeatedly denied any wrongdoing by the 78-year-old comedian who has gone from being America's pre-eminent father figure on "The Cosby Show" to pariah.