A new combination drug could suppress HIV for more than six months without needing a top-up, a groundbreaking study reveals.
The infusion offers hope of an alternative to the daily regimen of drugs that people living with HIV have to take to stay alive and prevent the onset of AIDS.
Previous attempts to make a long-lasting infusion failed because certain strains of HIV were resistant to the antibodies.
But this version, developed by scientists at Rockefeller University and the National Institutes of Health, successfully circumvented resistance by combining two antibodies together, suppressing HIV for more than 30 weeks in two people, and 15 weeks in most others.
‘This is an important step,’ Dr Carl Dieffenbach, director of the Division of AIDS at the National Institutes of Health, told DailyMail.com.
‘We knew that a single antibody couldn’t hold the fort, but this starts drawing parallels between the things we know are effective, and what’s possible.
‘It makes the argument that it may be doing something.’
HIV is no longer the killer it once was.
The advent of anti-retroviral therapy (ART) means that for most Americans it has become a life-long chronic illness, kept from progressing by a daily pill.
But there are issues with that. In any case – whether it’s ART or the contraceptive pill – users find that act of taking a daily pill arduous and often hard to stick to.
On paper, longer-lasting infusions with antibodies that combat HIV are the most we have as an alternative.
In practice, it has not yet been so simple.
Researchers at the University of Pennsylvania attempted the same in 2016with one strain, but the virus quickly became wise to the treatment, and resisted it.
Though many in the field subsequently dismissed the idea, scientists at Rockefeller, funded by the NIH and the Bill & Melinda Gates Foundation, explored whether they could give the infusion a boost by making it more complex. In essence, bolstering its armor.
The study, published today in the journal Nature, involved 11 people who were religiously taking a regimen of ART. Each of them have strains of the virus which are resistant to one of the antibodies.
After receiving the infusion, they stopped taking their ART.
Two people saw a resurgence of the virus within 12 weeks. But the rest saw impressive results. Two of them still had control over the virus 30 weeks after the infusion, while the other seven of them were virally suppressed for around 15 weeks.
It’s not clear why two of the study participants were protected for so long, though experts caution that a few select people can naturally maintain viral suppression for years.
Dr Dieffenbach also warns that ‘we have to remember, these patients were not directly suppressed by the antibodies. They started the antibody and it looks like one day after they stopped ART.’
He adds: ‘Keep in mind that most people who are HIV positive already harbor antibodies.’
So the question is: could suppression be maintained?
That’s something we don’t know. More studies are needed in more people, perhaps with more antibodies.
‘It’s a very tall order to ask,’ Dr Dieffenbach explains. ‘Can combinations of antibodies fully suppress?
‘There’s a huge amount of questions to work through, but the science is there.’