A U.S. patient with leukemia has become the first woman and third person to be cured of HIV after receiving a stem cell transplant from a donor who was naturally resistant to the virus that causes AIDS, researchers reported on Tuesday.

The middle-aged woman was treated with a new method: a transplant with umbilical-cord blood.

“This is now the third report of a cure in this setting, and the first in a woman living with HIV,” Sharon Lewin, President-Elect of the International AIDS Society, said in a statement.

The woman has been in remission and free of the virus for 14 months, without the need for potent HIV treatments known as antiretroviral therapy.

The two prior cases occurred in males – one white and one Latino – who had received adult stem cells, which are more frequently used in bone marrow transplants.