Stem Cell Research on Functional HIV Cure Advances to Human Trials
Research using man-made, blood-forming stem cells has shown great promise in animal experiments in suppressing HIV.
But now a grant from the California Institute for Regenerative Medicine (CIRM) has funded a clinical trial using those bioengineered stem cells to treat HIV patients who have lymphoma, a deadly cancer that eventually kills people with AIDS.
Although the trial funded by the $8.5 million grant will enroll volunteers who have both HIV and lymphoma, researchers hope the gene-modified, hematopoietic (blood-forming) stem cells will help control HIV as well as the lymphoma which persists because of the compromised immune system.
In a news release from the University of California-Davis, Mehrdad Abedi explained the trial will enroll patients who require a stem cell transplant as part of their standard treatment. “This provides us with an ideal setting to test the safety and efficacy of our bioengineered stem cells. Once the specially engineered stem cells are transplanted, new HIV-resistant immune cells will be produced. We’ll replace the patient’s immune system with HIV resistant cells, depleting the viral load associated with the disease without requiring conventional antiretroviral therapies.”
In animal models, Abedi and colleague Joseph Anderson developed a gene therapy strategy that “showed promise as a functional cure for HIV,” according to the news release. The research involved purifying HIV-resistant stem cells. They found a way to tag the HIV-resistant cells so that only those resistant cells will be transplanted, and not cells susceptible to HIV infection.
“While we’re planning to first test our therapy in patients with lymphomas, our ultimate goal is to expand this treatment to all HIV patients,” said Anderson, co-principal investigator on the grant and a researcher at the UC Davis Institute for Regenerative Cures. “If we can prove effectiveness in our upcoming clinical trial, this new approach could benefit a large number of HIV positive patients, both with and without HIV-related malignancies.”
The idea is similar in theory to that which cured Timothy Brown, the only man on earth ever cured of HIV. Brown suffered from acute myeloid leukemia and also was HIV positive. He was given bone marrow from a donor who had a rare genetic mutation that makes a person immune to HIV. Bone marrow transplants work because of stem cells. Other factors also likely contributed to Brown’s cure, however. You can read more about Brown’s cure in this report by Science.
According to the UC Davis news release, Anderson and Abedi said that if the clinical trial proves effective at curing HIV, they anticipate that the one-time cost of therapy using gene-modified stem cells will be “far less expensive than the estimated $1.5 million (and rising) cost of lifelong antiretroviral therapy for HIV patients.”
In other HIV-related research news coming out of UC Davis this week, a study published in PLOS Pathogens showed how scientists have found a new way to arouse HIV from reservoirs where it lies latent. This strategy, known as the “kick” in a one-two punch known as “kick and kill,” is needed because even when people appear to be “cured” of HIV (with the exception of Brown), it eventually comes back once antiretroviral therapy is stopped because the virus is hiding in places doctors and scientists can’t find it.
The research showed that the active compound in the cancer drug Picato “is a potential candidate for advancing HIV eradication strategies,” according to the res