A London Man Is Only The Second To Be Cured Of HIV

A man living in London is only the second person to be cured of HIV according to scientists. While originally known as the "London Patient," the man stepped out of the shadows this month identifying himself as Adam Castillejo. The man had two major diseases he was fighting at the same time with HIV and lymphoma. He received a stem cell transplant to treat his lymphoma and the donor had a gene mutation in the CCR5 gene.

The CCR5 gene is a key receptor for most strains of HIV. T cells or macrophages that don't express CCR5 are protected from infection with strains of HIV that use that receptor. After being treated with the transplant from the healthy donor, the HIV RNA in Castillejo's plasma has remained undetected for the last 30 months. That is described as a very long time to remain aviraemic off ART therapy for HIV.

The median time to viral rebound after cessation of ART is 2-3 weeks. Researchers performed a myriad of tests on the man to see if he was indeed cured of HIV including testing semen, cerebrospinal fluid, and tissue samples from the gut, lymph nodes, and rectum. The team says that low levels of HIV DNA were found in the node tissue and in blood CD4 T cells while all other samples were negative for HIV DNA.

The scientists do point out that the low levels of HIV DNA that were found in the samples weren't intact and were consistent with archived HIV DNA fragments that can't replicate. Researchers say that the man had greater than 90% chimerism in circulating T cells and concluded that the chance of future viral rebound when off ART is negligible. There is a discussion on if he is truly cured.

The other cured HIV patient is known as the "Berlin Patient" and has been off ART therapy for 13 years with undetectable plasma HIV RNA. One key area for researchers in being able to claim that HIV is cured is to determine how soon we can know if someone has been cured. Prolonged clinical observation and follow-up is required.