New Scientist reports that the Düsseldorf and London cases share stark similarities: both patients underwent bone marrow transplants as part of their cancer treatment, receiving cells from donors with the rare mutation of the gene CCR5. Brown has previously spoken of how he counts the date of the first stem cell treatment-February 6, 2007-as a new birthdate of sorts, because it was on this day that, unbeknownst to his doctors at the time, he would apparently be cured of HIV. In fact, Timothy Ray Brown, the original patient functionally cured of HIV, also known as the Berlin patient, nearly died from a host donor rejection during his treatment.
The key is finding a bone marrow donor with mutated CCR5 proteins, which prevent HIV from entering cells in the immune system, effectively "curing" HIV.
"The combination is paradigm shifting", Chloe Orkin, an HIV researcher at Queen Mary University of London who reported the trial findings at a Seattle conference, told Nature.
When an HIV positive patient achieves viral suppression and has an undetectable viral load, not only do they have a significantly increased likelihood of improved health outcomes, but it also eliminates their likelihood of transmitting HIV.
Other HIV patients from IciStem have also undergone similar bone marrow transplants for cancer, but they have not yet stopped taking the antiviral medications at this point.
"This will inspire people that cure is not a dream", Wensing said.
This complex treatment involves destroying a person's own immune system with high doses of chemotherapy or radiation.
The surgical replacement of bone marrow with the stem cells of patients who have the CCR5 genetic mutation must be followed by hospitalization where patients can be monitored for and treated against tissue rejection. This renders them resistant to most HIV infection.
While it proved to be successful for the Berlin, London, and Düsseldorf patients, the strategy used for these cases are not the way to eradicate HIV on a large scale. To end the global HIV epidemic, it is extremely important that there be 100 percent universal access to these important treatments - not just to those who can afford their expensive retail prices. Add to this that only about one percent of Caucasians are CCR5 negative-this being a mutation that only appears in European bloodlines-and it quickly becomes apparent that we can not feasibly use stem cell transplants to make every person with HIV enter remission.
The process is not scalable, since it can not be used on all HIV patients - only a small group of cancer patients failing all other cancer treatment interventions who also have HIV.
He did not experience HIV rebound, during the 18 months he did not take anti-viral medication.