A man in Brazil appears to have been cleared of an HIV infection and in long-term remission after receiving a highly intensified cocktail of drugs, in a new experimental therapy.
After receiving the treatment of antiretroviral drugs and vitamin B3 for almost a year, the patient stopped taking other HIV treatments in March 2019 and still has no detectable virus or antibodies in his blood.
The professed feat has earned both fascination and skepticism from scientists, with outside experts warning the work needs further long-term independent verification and more information needs to be published. They were also quick to stress it’s still too early to proclaim the man is “cured” from HIV.
If the researchers’ estimations are accurate, however, the patient could represent the third case of a person previously diagnosed with HIV who has achieved long-term remission. It would also be the first time HIV has been eliminated in an adult using solely drugs without a bone marrow or stem cell transplant.
As reported by the Associated Press and Science, the feat was announced on Tuesday, July 7 by Dr Ricardo Diaz of the Federal University of São Paulo in Brazil, the clinical investigator running the study, during a press conference held at the virtual AIDS 2020 conference.
Known as the “São Paulo Patient,” the unnamed 36-year-old Brazilian man started this treatment 2 months after being diagnosed with HIV in October 2012. He was one of five people who took part in the experimental trial, although he was the only patient to receive promising results.
The human immunodeficiency virus (HIV) is extremely tough to "cure" because it can lay dormant, protected from any treatments or immune response, then bounce back and fully reactivate. For example, people with HIV can take antiretroviral medications, which work by stopping the virus replicating in the body and holds the infection at bay. This reduces the amount of HIV virus in the blood, known as the viral load, allowing people to live long and healthy lives. It also means there is a near-zero risk of transmitting HIV to a partner through sex. Nevertheless, if a patient stops taking the treatment, the infection can reactivate even if they previously had no detectable HIV in the blood.
This radical treatment, however, appears to overcome this hurdle. The treatment involves taking frequent doses of three drugs, including maraviroc (an entry inhibitor that helps to block HIV from entering human cells), dolutegravir (an antiretroviral drug), and nicotinamide (aka vitamin B). After receiving this treatment for 48 weeks, he then stopped taking his standard antiretroviral drugs. Over one year later, there is still no detectable virus in his tested blood and tissue samples, the researchers say. There is also no evidence of antibodies in his body, which further hints the body has been rid of the infection.
So far, so good. However, independent experts urge for caution when interpreting these preliminary results. First of all, very little information about the case is currently published for other scientists to critique and analyze. There's also no certainty that long-term (effectively permanent) remission has been achieved yet.
“Altogether, this is a remarkable claim, but exceedingly frustrating given the lack of detail about the virological status of the “Sao Paulo Patient” or a plausible model for effect of vitamin B3,” commented Dr Jonathan Stoye, an independent expert from the Head of the Retrovirus-Host Interactions Laboratory at the Francis Crick Institute. “I am not convinced.”
“Am I skeptical? Of course. Am I intrigued? Absolutely,” Dr Steve Deeks, an HIV researcher at the University of California, San Francisco, who was also not involved in the work, told the New York Times.
According to the United Nations, 40 million people worldwide live with HIV, and although there is available medication to prevent and treat it, and promising new treatments in the works, we still don't have a vaccine or a cure.
