Experts say gene therapy could finally be used to treat Human Immuno-deficiency Virus (HIV) and Acquired Immune Deficiency Syndrome (AIDS) – after a decade of trying to replicate the transplant that cured a patient in Germany.
Although there is no definitive cure for the disease, there have been many advances in treatment that have made it possible for patients to live longer lives.
Last year, the United States (U.S.) Centers for Disease Control and Prevention declared that people who religiously take their HIV medication for six months can reach a point where their virus is not transmittable.
However, experts say gene editing — which has been recently approved by the Food and Drug Administration (FDA) to treat cancer and a rare form of childhood blindness — has been developed to such an extent that it could be viewed as the best answer for a cure.
Matt Chappell, of San Francisco, California, has been taking the strongest AIDS drugs for more than a decade, but they weren’t able to full control his HIV infection.
He then participated in a gene therapy experiment in 2014 where scientists removed some of his blood cells, disabled a gene to help them resist HIV, and returned these ‘edited’ cells to him.
So far, it has given Chappell the next best thing to a cure.
“I’ve been off medications for three and a half years,” he said. He even was able to keep the virus in check despite cancer treatments last year that taxed his immune system.
Chappell was lucky, though. Only a few of the 100 others in those experiments were able to stay off HIV drugs for a couple years; the rest still need medicines to keep HIV suppressed.
Now researchers think they can improve the treatment and are trying again to tackle HIV by doctoring Deoxy ribonucleic Acid (DNA)/genetic material. New studies to test these tweaked approaches in people are getting underway.
“Gene therapy techniques have advanced greatly,” said Dr. Otto Yang of the University of California Los Angeles (UCLA) AIDS Institute, one place working on this. “A lot of people are thinking it’s the right time to go back.”
They include Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, which is funding some of the new studies.
Although Fauci doesn’t think the technique will become common because millions of people do well on existing treatments, he says it could help those who can’t easily control the virus, and should be pursued because it holds potential for a cure.
“They’re very bold, innovative techniques, mostly to try and cure people,” he said. “It’s worth trying because the science is there.”
More and more experts are turning to gene-editing to prevent HIV.
A 2016 study published in the Scientific Report revealed researchers at Temple University developed a gene editing method that detects HIV DNA in people’s T cell genome, the DNA set of a type of white blood cells.
Once the DNA is edited out, the loose ends of the genome that were once attached to the HIV infection are reunited by the cell’s own DNA repair system.
Not only is the cell HIV-free, but it’s also protected from a new infection.
So far, Timothy Brown is the one of only two people in history to have been cured of HIV.
He had a bone marrow transplant more than a decade ago to cure his leukemia, and the stem cells came from a donor with natural immunity to HIV.
The donor lacked a common gene that makes an entryway HIV uses to infect T cells.
This transplant, which replaces a sick person’s immune system with stem cells from the bone marrow of a healthy person, gave Brown that protection, but procedures like that are too risky and impractical for wide use.
In fact, attempts to replicate Brown’s procedure has been deadly.(Guardian)