"I am just focusing on staying healthy and getting ready for the season," Rose said in a statement. "I am not going to comment other than to say: I know the truth, and am confident I will be proven innocent."
The lawsuit, first reported by TMZ Sports, was filed Wednesday by an unidentified woman who said she dated Rose from 2011 to 2013. She is accusing Rose and two friends of slipping a drug into her drink and later committing sexual acts against her will. The incident, she alleges, occurred in August 2013.
The lawsuit was unclear regarding the timeline of the incident, but an attorney for the woman told ESPN it took place on one day.
"The incident occurred in the early morning of Aug. 27, 2013. The plaintiff had visited the defendant's residence the night of Aug. 26, 2013, and returned to her residence in the early morning of Aug. 27, 2013," attorney Brandon J. Anand said.
A spokesperson for Rose, Lisa Cohen, acknowledged in a statement to several media outlets that Rose and the woman were in a consensual, nonexclusive relationship but said the accusations are "completely false and without any factual basis."
"We have complete confidence that the case will be dismissed," Cohen added.
The Bulls issued a statement early Thursday morning, saying: "We just learned about this matter and do not know all the facts. It would be inappropriate to comment further at this time."
ESPN.com's Brian Windhorst contributed to this report.