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HIV Patients Potentially Cured After Stem Cell Transplants to Treat Blood Cancer

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Two men with HIV may have been cured after they received stem cell transplants to treat lymphoma, a type of blood cancer.

Their doctors, presenting last week at the International AIDS Society Conference in Kuala Lumpur, said that one of the men received stem cell transplants to replace his bone marrow about 3 years ago and the other 5 years ago. Their regimens were similar to one used on Timothy Ray Brown, the “Berlin patient” who has been living HIV-free for 6 years and is the only adult to have been declared cured of HIV.

Last July, doctors announced that the two men—the “Boston patients”—appeared to be living without detectable levels of HIV in their blood, but they were still taking antiretroviral medications at that time.

Timothy Henrich, M.D., an HIV specialist at Brigham and Women’s Hospital in Boston, who helped to treat the men, says that they have now stopped their antiretroviral treatments with no ill effects. One has been off medication for 15 weeks and the other for 7 weeks. Neither has any trace of HIV DNA or RNA in his blood, Dr. Henrich says.

If the men stay healthy, they would be the third and fourth patients ever to be cured of HIV, after Brown and a baby in Mississippi who received antiretroviral therapy soon after birth.

“We’re being very careful not to say that these patients are cured,” said Daniel Kuritzkes, M.D., a colleague at Brigham who also worked with the men. “But the findings to date are very encouraging.”

The Boston patients’ treatment differed from the Berlin patient’s regimen in one key way:  Brown was given stem cells that were predisposed to resist HIV infection because the donor happened to have a mutated version of a key protein — CCR5 — that is needed for HIV to infect cells. So Brown’s transplant was akin to gene therapy with HIV-resistant cells.

But the Boston patients received stem cells without the protective mutation. The transplanted cells must therefore have been protected from infection by the antiretroviral drugs taken during cancer treatment.

Their doctors think that graft-versus-host disease—a post-transplant reaction in which donated cells kill off a patient’s own cells—may have then wiped out the patients’ HIV reservoirs, potentially curing the men.

The finding is very important for people with HIV who also need blood-cell transplants, but the treatment is unlikely to be used more generally because the risks from transplants are high.

Separately, the International Maternal Pediatric Adolescent AIDS Clinical Trials (IMPAACT) Group, based in Silver Spring, Maryland, is trying to replicate the Berlin patient’s cure by giving CCR5-mutated HIV-resistant blood from umbilical cords to children and adults with HIV and cancer. 

Learn more:
http://www.nature.com/news/stem-cell-transplants-may-purge-hiv-1.13297
http://impaactnetwork.org/