Positive Times: A "Cure" for HIV

By Dr. Dawd Siraj

 

There have been many scientific advances in HIV care and prevention since the first cases of HIV/AIDS were reported in 1981.  However, one goal that science has not been able to reach is that of an HIV vaccine or cure. So it was very exciting to read the headlines about an HIV "cure" announced at a major scientific HIV conference (CROI) in March of 2019. Since the release of those results, the HIV community and the general public have been asking whether we have finally reached the goal of an HIV "cure". 

 

You may have heard of Timothy Ray Brown, also known as the "Berlin Patient" who in 2008 was the first person living with HIV (PLWH) to be functionally "cured" of HIV after receiving a bone marrow stem cell transplant to treat his cancer. So what is a "functional cure"?  This means that Timothy Brown is off of ART (HIV medications) and doctors have been unable to find HIV in his body. Scientists also sometimes call this HIV "remission" instead of an HIV "cure".

 

The March 2019 reports are of a second and possibly third patient "cured" of HIV. The "London" patient and the "Düsseldorf" patient each received bone marrow transplants from donors with a rare genetic mutation that is resistant to most types of HIV. Each of these patients has been in HIV "remission" since stopping their HIV medications; the "London" patient since September 2017 and the Düsseldorf patient since November 2018.

 

Is this "cure" an option for me?

 

While these are very important achievements, we have to think carefully about how bone marrow stem cell transplants can be used. Right now, a bone marrow stem cell transplant is a procedure that’s only used as a last resort for certain types of bone marrow-related cancers. A donor must first be identified, and just a tiny percentage of bone marrow donors have the rare mutation that makes one resistant to HIV. Even when a donor is available, the procedure is very risky, expensive, and complex and the recipient’s immune system will be suppressed for the rest of their life. This means the person could be at risk of developing life-threatening conditions, which is far riskier than controlling HIV with a daily pill, even if it is a lifelong commitment.  Considering all this, a bone marrow stem cell transplant is not a practical strategy to "cure" HIV on a large scale.

 

There have been many advances since the first cases of HIV/AIDS in 1981. We have now reached a point where many PLWH can achieve an undetectable HIV viral load by taking just one pill, once a day. Scientific evidence clearly shows that PLWH with a durably undetectable HIV viral load do not transmit HIV to their sexual partners, known as Undetectable = Untransmittable or U=U. Added to this are prevention methods PrEP (pre-exposure prophylaxis) and PEP (post-exposure prophylaxis), that can help further prevent HIV transmission. These advances and achievements are safe, cost-effective, and easily scalable strategies to control HIV while steps are made towards an HIV cure that is practical for the majority of PLWH.