A Second Patient Has Been Cured of HIV—How Does That Even Happen?
Investigators say the so-called "London patient" is in long-term remission.
For the second time in history, medicine has achieved what was once the unthinkable: Not just a treatment for HIV/AIDS, but what seems to be an outright cure.
A person known only as the "London patient" has been free of the HIV virus for more than a year since from a donor who had a specific gene mutation that prevented HIV from taking hold. Researchers reported the case in the journal Nature and at this week's Conference on Retroviruses and Opportunistic Infections in Seattle.
While the investigators are calling this a "long-term remission" rather than a "cure," others are using the C word.
The only other time a patient was "cured" of HIV/AIDS was 12 years ago, in 2007. The "Berlin patient," aka Timothy Ray Brown, now 52 and living in Palm Springs, California, is widely considered cured because he has been HIV-free without anti-HIV drugs for more than a decade.
"The concept of a cure for HIV is really being able to remove the virus," David Rosenthal, DO, PhD, medical director of the Center for Young Adult, Adolescent, and Pediatric HIV at Northwell Health in Great Neck, New York, who was not involved in the London patient's care, tells Health. "For hepatitis C, we can completely cure people of the virus so they're no longer infected. HIV is like high blood pressure; we can control the symptoms, but we can't remove the cause."
The holy grail of HIV/AIDS research has been to rid the body of the virus permanently.
The Berlin patient's cure was one of magnificent serendipity. He underwent a bone marrow transplant to treat not AIDS but leukemia. Bone marrow transplants have long been used to treat this type of blood cancer. The bone marrow donor turned out to have a mutation that prevented HIV from digging in. The donated cells, with their ability to fight HIV, have now taken root in Brown's body.
"What we're talking about with a bone marrow transplant is getting rid of someone's immune system and giving them back someone else's immune system," says Dr. Rosenthal.
Brown, though, had terrible side effects from the treatment and nearly died. Partly for that reason, doctors have not considered this a viable option for HIV/AIDS patients.
RELATED: 16 Signs You May Have HIV
Fast forward to 2016 when the London patient received a bone marrow transplant from a donor with the same mutation. Again, the procedure was intended to treat Hodgkin's lymphoma, not HIV/AIDS. Like Brown, this patient also received immunosuppressive drugs after the transplant. The London patient stopped anti-HIV drugs more than a year ago (in September of 2017) and has had no sign of the virus since. Unlike Brown, though, the London patient did not have to go through a horrific, near-death experience to reap the benefits of the therapy.
"The question is, is it in remission, which means that we've been able to stop the virus from reproducing itself temporarily, or is it truly cured, in which case it won't ever come back?" says Dr. Rosenthal. The London patient has been free of the virus for a substantial amount of time, he acknowledges, but at this point, "it's still possible for the virus to come back."
Today, people with HIV are able to live essentially virus-free with a minimally disruptive regimen of pills.
"Medications used to be much more difficult and have higher side effects," says Dr. Rosenthal. "We're fortunate now in that we can have many patients treated with one pill, once a day. That completely suppresses the virus [making it] undetectable." That may sound like a cure but it's not: When the medications stop, the virus comes back.
So does the case of the London patient mean we're on the verge of having a widely available cure for HIV/AIDS? Not so fast.
"We really don't know what the long-standing significance of this is," says Dr. Rosenthal. "We can't completely eradicate everyone's immune systems and this, in and of itself, is not a suggested mechanism for curing HIV." Bone marrow transplant procedures are rough, involving heavy-duty drugs, serious side effects, and the possibility of death.
But the current news "does teach us a great deal about the HIV virus and how we can possibly create other ways to eradicate it," says Dr. Rosenthal. "I don't think doing wide-scale bone marrow transplantation is on anyone's radar as a future option."
Researchers are tracking other HIV/AIDS patients who have received bone marrow transplants from donors with the same mutation that cured the Berlin patient. "Patients are being monitored to see how well they do and how well they continue to do,” says Dr. Rosenthal. "If you don't have any virus that can be detected for an extended period of time, when does that become a cure instead of remission?"
Both the London patient and those currently being monitored, he adds, “help us understand how we can overcome the virus and design a true cure.”
To get our top stories delivered to your inbox, sign up for the