Finding an HIV cure has always proven difficult because of a viral reservoir of HIV cells that is untreatable by antiretroviral drugs, but Spanish doctors may have discovered a solution.

Doctors believe six people afflicted with HIV have had the virus eliminated from their body and one may even have been completely cured of the virus, according to a study published in the journal Annals of Internal Medicine. The study was carried out by scientists from the Institue of AIDS Research IrsiCaixa in Barcelona and the Gregorio Marañón Hospital in Madrid, Spain, and gives new hope to developing a reliable HIV cure.

The success was achieved by using stem cell transplants. After the transplants, none of the six patients had the presence of HIV detectable in their blood and tissues after the treatment. One patient did not have any HIV antibodies either, suggesting he may have been completely cured of the virus.

The stem cells used for the HIV treatment were obtained from umbilical cords and the bone marrow. The patients are still on antiretroviral drugs, but the scientists think the source of the stem cells used and the length of time it took for the recipients’ bodies to completely replace their cells with the donor cells may have resulted in completely eliminating HIV. In one of the six patients, it took 18 months for the body to adopt the donor cells.

‘The Berlin Patient’ – Some People Are Immune to HIV/AIDS

With the success achieved with this study, the researchers hope the treatment can be replicated to develop an HIV cure that is reliable and widely available.

IrsiCaixa researcher Maria Salgado and Mi Kwon, a hematologist at Gregorio Marañón Hospital led the study. According to them, antiretroviral drugs have not been engineered yet to fully cure HIV infection because of the viral reservoir created by cells destroyed by the HIV virus. This virus load remains passive in the face of drugs, while the immune system is powerless against them.

Researchers are hoping stem cell transplants can be the answer to the problem of the viral reservoir. Previously, medical specialists used stem cell transplantation only for chronic blood diseases.

The idea to use stem cell transplants for an HIV cure arose out of the case of Timothy Brown, known as ‘The Berlin Patient”. Brown had both leukemia and HIV and underwent stem cell transplantation to treat leukemia.

The individual that donated stem cells to Brown had a cell mutation known as CCR5 Delta 32. This mutation makes the individual immune to HIV infection. It is now 11 years since Brown was treated with the donor’s stem cells, and he does not have HIV in his system even though he no longer uses antiretroviral medication.

Brown is considered the only person in the world to be cured of HIV. This has given scientists hope that HIV/AIDS can still be cured – with stem cell transplants.

Study Success Is Basis for Developing New Treatment for HIV Cure

“Our hypothesis was that, in addition to the CCR5 Delta 32 mutation, other mechanisms associated with transplantation influenced the eradication of HIV in Timothy Brown,” said Salgado.

The six patients from the study in Spain did not receive blood cells from donors with CCR5 Delta 32. Mi Kwon said these patients were chosen for the study in order to test other ways their HIV virus could be eliminated.

With several tests, it was found that five of the patients did not have any HIV in their bodies and the sixth individual did not have any viral antibodies after the treatment. Salgado said the next step is stopping the antiretroviral treatment to see if the virus returns and conducting a full clinical trial.