After money manager Jeffrey Epstein was charged in July with soliciting sex from prostitutes, several recipients of his donations distanced themselves from the New York billionaire. But though Epstein wrote a $6.5 million check to Harvard—with the possibility of additional millions down the line—the University said yesterday that it has no plans to return the gift.

The donation, first announced in 2003, finances the work of mathematical biologist Martin A. Nowak, the director of Harvard’s Program for Evolutionary Dynamics. Epstein agreed to consider raising his total contribution to $30 million after a review of the program’s progress. That review has not yet taken place, according to the University.

After Epstein was charged with soliciting prostitution at his Palm Beach, Fla., mansion, several politicians who had accepted campaign money from the billionaire returned the donations. They include Eliot L. Spitzer, the New York attorney general who is running for governor; Mark A. Green, a Democratic candidate for attorney general of New York; and New Mexico Gov. Bill Richardson, according to the New York Times and New York Daily News.

Harvard will not join them. “Mr. Epstein’s gift is funding important research using mathematics to study areas such as evolutionary theory, viruses, and cancers,” a Harvard spokesman said yesterday. “The University is not considering returning this gift.”

Interim President Derek C. Bok, who served as University president from 1971 to 1991, wrote in an e-mail that he was unfamiliar with the specific details of Epstein’s donation, but stands by his 1979 open letter to the Harvard community stating his views of the ethics of accepting controversial gifts.

In “extreme cases,” Bok wrote in the letter, Harvard should refuse contributions from donors who have earned their money immorally, “but on the whole, I would be inclined to accept such donations on the ground that the tangible benefits of using the money...should overcome the more abstract, symbolic considerations that might lead us to turn down such benefactions.”

“I am not yet persuaded that Harvard should have an obligation to investigate each donor and impose detailed moral standards” prior to accepting donations, he wrote then.

Epstein, whose defense attorneys include Alan M. Dershowitz, the Frankfurter professor of law, last month pled not guilty to the charge of soliciting prostitution.

In an affidavit released by the Palm Beach Police Department, the police said it had probable cause to also charge Epstein with lewd and lascivious molestation and unlawful sexual activity with a minor. (Epstein, through his attorneys, has denied knowing that any of the women who visited his house were underage.) A grand jury later declined to indict Epstein on those additional charges.

—Daniel J.T. Schuker contributed to the reporting of this story.

—Staff writer Nicholas M. Ciarelli can be reached at ciarelli@fas.harvard.edu.