July 2014
Examples of media coverage:
- HIV “Cleared” in Two Australian Men after Bone-Marrow Transplants– Sydney Morning Herald, July 19, 2014
- HIV Said Cleared in Two Bone Marrow Transplant Patients– Bloomberg News, July 18, 2014
- Cancer Treatment Clears Two Australian Patients of HIV– Nature News, July 18, 2014
Original sources:
- Presentation at the International AIDS Society Towards an HIV Cure Symposium, Melbourne, Australia, July 19, 2014 (see abstract #PE48LB on page 74 of the symposium abstract book)
- Two Sydney Men Clear HIV after Bone Marrow Transplants – University of New South Wales press release, July 18, 2014
TAG’s commentary:
The headlines relating to this story are very misleading. There is no evidence as yet that HIV has been “cleared” from these two individuals, as both remain on ART. Rather, HIV is undetectable by a variety of tests. Most of the stories do mention this critical fact, even though the headlines are inaccurate. A news item in the scientific journal Nature, which might be expected to be more accurate than other media, erroneously describes the men as “apparently HIV-free.” An article in the New Scientist also specifically addresses concerns about the misleading coverage:
Latest HIV “Cure” Claims Prompt Calls for More Caution – Andy Coghlan and Jessica Hamzelou, New Scientist, July 22, 2014
As this and several other articles point out, recent experience strongly cautions against assuming that the inability to detect HIV means that the virus is no longer present in the body. A previously published report regarding two HIV-positive individuals in Boston who received stem cell transplants to treat cancers described an absence of detectable HIV. These cases received a lot of publicity in July of last year because HIV remained undetectable after ART was interrupted. However, in December, it was announced that viral load had rebounded in both individuals, after 12 weeks in one case and 32 weeks in the other. These results were published on July 22 in the journal Annals of Internal Medicine.
Context:
Stem cell transplantation is a high-risk procedure used to treat certain serious cancers. There is significant interest in studying people with HIV who undergo stem cell transplants to treat cancers because of evidence that the procedure contributed to eliminating HIV in Timothy Brown, the only person considered cured of HIV infection. However, Brown received stem cells from a donor with a genetic mutation known as CCR5Δ32, which renders cells resistant to most HIV strains. The Boston patients did not receive stem cells from donors with this mutation.
Of the two Australian cases, one received stem cells from a donor heterozygous for the CCR5Δ32 mutation (they inherited the mutation from one parent, not both), meaning their cells are less susceptible to HIV, but not resistant. The other received stem cells from a normal donor. Conducting an ART interruption is the only way for researchers to assess whether these individuals will maintain undetectable levels of HIV in the absence of ongoing treatment.
A number of research studies are looking into the effects of stem cell transplantation in HIV-positive people who require the procedure as part of treatment for cancer. Two trials in the United States are attempting to find compatible stem cell donors homozygous for the CCR5Δ32 mutation in order to try to repeat the cure achieved in Timothy Brown.
- Allogeneic Transplant in HIV Patients (BMT CTN 0903)
- IMPAACT P1107: Effects of Cord Blood Transplantation with CCR5Δ32 Donor Cells on HIV Persistence
In Europe, the European HIV Cure and Transplant Consortium (EHCTC) is also aiming to try to identify stem cell donors homozygous for the CCR5Δ32 mutation for HIV-positive people requiring stem cell transplants to treat cancers.