‘San Francisco Patient’ Is the Second Person Effectively Cured of HIV

A second person, referred to in the research as the “San Francisco Patient,” has been effectively cured of HIV the virus that caused AIDS.

Time: According to a report published Monday in the Annals of Internal Medicine, a now 31-year-old woman who was diagnosed with HIV in 2013 only took antiretroviral therapy for six months during pregnancy to prevent transmitting the infection to her baby. Yet multiple sophisticated tests looking for genetic evidence of HIV in the patient’s blood showed no intact virus in her cells, says Dr. Xu Yu, who led the research team reporting on the case. She’s a principal investigator at the Ragon Institute of Massachusetts General Hospital, MIT and Harvard, as well as an associate professor of medicine at Harvard Medical School. The findings suggest that the patient’s immune system was even able to clear the reservoirs of HIV that allow the virus to continue replicating for decades. Current anti-HIV drugs can lower virus levels to undetectable levels but can’t completely rid the body of these lingering reservoirs of the virus.

“There is no way to ever say we have proof that there is not a single virus in this patient,” says Yu. “The only thing we can say is that after analyzing a large number of cells from the patient, with the technology in our lab we cannot reject the hypothesis that the patient probably reached a sterilizing cure by natural immunity.”

There have been previous reports of patients who stopped taking anti-HIV medications and achieved undetectable virus levels for years, including Timothy Ray Brown, who’s also known as “the Berlin patient,” and Adam Castillejo, “the London patient.” Both, however, had been diagnosed with cancer and benefited from having a stem cell transplant to treat it, which replaced their immune cells with ones from donors that included cells that could block HIV infection. They also likely continued to harbor latent reservoirs of HIV, which have been eliminated in the patient Yu is describing.