Anti-HIV drugs are very good at controlling infection, but the moment a patient stops taking them, the overwhelming majority of the time the virus bounces back with a vengeance. For a small percentage of the population, however, a specific genetic variation allows them to control the virus themselves, and in even rarer circumstances, people manage to keep the virus at bay after ceasing treatment – for no immediately obvious underlying reason.
Yesterday, at an international AIDS conference in Canada, another one of these unusual cases was presented, which scientists are hopeful could lead to a better understanding of how a minority manage to restrain HIV in the absence of drugs. The individual is an 18-year-old French woman who was infected around the time of birth and immediately put on antiviral treatment. This intense regime was discontinued six years later, but remarkably she remains symptom-free. As far as doctors are aware, this is the longest a pediatric case has stayed in remission after treatment was stopped.
The teenager is the latest addition to a small group of known individuals who promptly started anti-HIV treatment following infection, but managed to stave off symptoms for an unexpectedly long period after they stopped taking them. These include the so-called VISCONTI cohort of 20 individuals in France and the famous “Mississippi baby.”
Similar to the latter case, the woman described became infected from her HIV-positive mother at or around the time of birth. But unlike the Mississippi baby, who was promptly put on a cocktail of anti-HIV drugs, the French child was initially only given one. A couple of months later, tests revealed that she had high levels of the virus in her blood, so she was put on a more intense regime of several drugs.
Despite advice from doctors, the parents of both children decided to take them off treatment at a later stage, but here is where the cases become more interesting: While the American girl only managed to fight off the virus for just over two years, to this day the French girl appears healthy and the virus remains undetectable in blood samples. This is similar to those in the VISCONTI cohort, a small group of adults who were diagnosed promptly following infection and consequently put on treatment very early on. These individuals stayed on drugs for around three years, but the virus didn’t bounce back for an average of 10 years.
This raises an important question: Could the VISCONTI patients and the French girl have controlled the virus even if drugs were not given? This would place them in the so-called “elite controllers” category, a small percentage of people whose immune systems are able to prevent the virus from taking over the body even in the absence of drugs. This would mean that their unusually prolonged remission was not attributable to the early treatment regimen, but instead maybe some genetic or immunological factor.
That being said, interestingly both those in the VISCONTI group and the French teenager actually possess gene variations that result in weaker immune responses, which usually mean that the early stages of infection are worse than normal. But it’s possible their dampened immune system worked to their advantage, Science points out, as it may have reduced the pool of cells available to the virus when it first entered the body.
But even if these rare cases are attributable to underlying factors, rather than the rapid onset of treatment, there is still a growing amount of evidence to highlight the benefits of starting treatment as early as possible, rather than delaying.
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