Toronto Man in HIV Remission After Stem Cell Transplant

A 36-year-old Toronto man who has lived with HIV for 27 years is in remission and may be cured of the virus following a bone marrow transplant for leukemia, his doctors announced this week. The procedure, performed at Princess Margaret Cancer Centre, used stem cells from a donor with a rare genetic mutation that confers natural resistance to HIV. If the patient maintains remission for another two and a half years, he would become the 11th person worldwide confirmed cured of the virus.

The patient, whose identity has not been disclosed, was first diagnosed with HIV and an aggressive lymphoma in 1999. He managed the condition with antiretroviral therapy for nearly three decades until routine blood tests in July 2020 revealed abnormalities. Further evaluation at Princess Margaret Cancer Centre led to a diagnosis of acute myelogenous leukemia, a fast-progressing blood cancer that required a stem cell transplant to replace his diseased bone marrow.

Led by a team from the University Health Network, Unity Health Toronto and the University of Toronto, clinicians sought a donor whose cells could address both the leukemia and the HIV. They identified a match with the CCR5-delta 32...