Study reignites interest in HIV cure
At the beginning of March, news reports began circulating about a man from London who has, according to researchers, become only the second person in the world to be cured of HIV. Here, we take a closer look at what was reported and what it could mean for the future of HIV treatment.
What was in the news?
A string of news stories appeared online at the start of March, reporting that a man from London has become only the second person in the world to be cured of HIV.
The stories were prompted by the publication of an article in the Lancet HIV journal reporting on the case of Adam Castillejo, who has been free from HIV more than 30 months after undergoing a stem cell transplant and stopping HIV medication.
The journal article provided an update on an earlier report from 2019, where Mr Castillejo, then referred to as the 'London patient', had been in remission of his HIV for 18 months.
Speaking to the BBC, lead researcher Prof Ravindra Kumar Gupta, from the University of Cambridge, was confident that the results represented an HIV cure with 'almost certainty'. However, it was noted in the article that latent remnants of HIV remain in Mr Castillejo's body, so it is impossible to be absolutely certain that he is cured.
The research is being conducted by academics from UCL, Imperial College London, the University of Cambridge and the University of Oxford.
What was the treatment?
Mr Castillejo has been participating in IciStem, an international study investigating the potential for an HIV cure linked to stem cell treatments for blood disorders.
As part of the study, he underwent chemotherapy and stem cell translplantation to treat Hodgkin lymphoma. Importantly, the donor cells used to treat the lymphoma contained a mutated version of a protein found on the surface of white blood cells.
Normally, this protein is used by the HIV virus to enter a person's blood cells, and then multiply. However, the mutated version of the protein received by Mr Castillejo appears to be resistent to HIV.
Following the stem cell transplant, he continued to take antiretroviral treatment for his HIV for 16 months, before deciding, along with the clinical team, to stop taking it to see if his HIV was in remission. Follow up reports at 18 and 30 months have confirmed that his HIV remains in remission.
Has this happened before?
As already mentioned, Mr Castillejo is the second person to reportedly be cured of HIV.
The first was Timothy Brown, known as the 'Berlin Patient', who underwent similar stem cell treatment after being diagnosed with myeloid leukemia in 2007. Mr Brown's case was one of the inspirations that led to the IciStem study, and he acted as a member of the project's community board.
Unfortunately, Mr Brown passed away in September last year after his leukaemia returned.
Does this mean we're close to a cure for HIV?
In a word, no. Despite the encouraging results of this study, we are still a long way from having a scalable cure for HIV that could be rolled out around the world.
The approach taken by researchers involved use of chemotherapy alongside stem cell transplantation and is an agressive therapy.
Acknowledging this, Prof Gupta told BBC News that the treatment being studied was high risk and only used as a 'last resort' for patients who had HIV along with specific life-threatening blood disorders.
However, what this latest breakthrough does do is offer hope that a cure may be something that can be identified in future.
What does that mean for HIV treatment in Scotland now?
Although research into a cure will continue, we are fortunate in Scotland that we have access to highly effective treatments that can control HIV and even help to prevent its spread.
HIV treatments work by reducing the amount of HIV in the body. When this viral load gets below a certain point, HIV becomes undetectable and it usually takes up to six months of treatment to reach this point.
A person living with HIV, who is on treatment and has an undetectable viral load cannot pass on HIV to sexual partners - we therefore say that their HIV is untransmittable.. This is known as U=U or undetectable=untransmittable.
Because there isn't currently a cure, HIV treatment is something a person will take for life. At the moment, that means people living with HIV will generally take between 1 and 4 pills a day, depending on the combination medicines they are prescribed.
However, earlier this year, new, long-acting treatments were approved in the EU that could replace daily pills with monthly or two-monthly injections. We will be keeping an eye on how this develops in Scotland.
While the hunt for an HIV cure continues, we can be reassured that continuing improvements to treatment are helping people with HIV to take control, live long, healthy lives and contribute to prevention of new infections.