In 2007, Timothy Brown, aka Berlin Patient, became the first man to be “cured” of HIV. Slightly over a decade later comes the “London Patient” — good news to tens of millions of HIV/Aids patients and hundreds of millions of their loved ones praying for a cure to be found.
Optimistic doctors and researchers say these two cases are, indeed, milestones worth celebrating. But their pessimistic colleagues say a medical panacea for HIV is not in the horizon yet. Nonetheless, many take it as a harbinger that humanity will vanquish HIV.
The two cases have an element of serendipity. The “London Patient”, who is anonymous, was diagnosed with HIV in 2003 and had been using antiretrovirals (ARVs). He was later diagnosed with Hodgkin’s Lymphoma, which was managed through chemotherapy, and in 2016 underwent a bone-marrow transplant. He is in a remission state; there is no evidence of the virus in his body system.
The “Berlin Patient” was also on ARVs before being diagnosed with Myeloid Leukaemia, which failed to respond to chemotherapy. He underwent two bone marrow transplants and, in 2007, was reported to have been “cured”.
In both cases, the targeted treatment was cancer with HIV being collateral damage. In both transplants, the donors had a rare mutation protein, CCR5, which rests on the surface of certain immune cells. HIV uses the protein to enter those cells but cannot latch onto the mutated version.
The protein may just hold the key to HIV cure, but why has it taken scientists a decade to replicate this? It goes to say that there will be a lot of soiling of hands in the labs before scientific community enjoys a eureka moment in the HIV war.
Bone marrow transplant, or simply stem cell transplant biotechnology, has been used in the treatment of some types of cancers. The stem cell transplant applied in these two cases is a relatively new but highly promising technology being used in the treatment of some medical conditions.
Stem cells can transform into different cell types, sometimes after long periods of inactivity. When a stem cell divides, each new cell has the potential to either remain a stem cell or become another type of cell with a more specialised type and, subsequently, function. They serve as an innate repair system to replenish other cells.
Stem cell biotechnology taps the pluripotent (ability to replicate and change into other cells) nature of stem cells. Researchers can redirect the cells to form new ones of their choice, which can be used in the treatment of diseases like cancers, stroke, burns, type 1 diabetes and probably HIV/Aids.
Being a relatively new medical technology, controversy is expected and already a lot of it have been documented.
Although stem cells can be harvested from adult bone marrow and fat, embryonic stem cells got from 3-5-day-old embryos are the best due to their versatility. The latter raised a lot of moral issues; in vitro embryos are mostly used.
Another issue that might add a dark cloud to this journey towards discovery of HIV cure is the application of this technology. Maybe you are already wondering why a black patient is yet to make it onto this seemingly prevented list? The technology is expensive and dangerous, making it unfeasible for the millions of patients receiving ARV treatment. But like any other method, crude as it may look at its infancy, it can be refined and be subsidised to make it accessible to all.
Before governments started giving ARVs free of charge, many people died because they could not afford them. Even if this technology were proven to work and approved for use, it could take a little bit longer for it to diffuse to the commoners.
The beauty of science is that it is stubbornly resilient; it draws its nutrients from difficulties and suffers not from stagnation it grows in whichever conditions it finds itself. A lot of research is going on towards HIV cure and, who knows, one day we may wake up to naked scientists on our streets shouting “Eureka!”. Until then, HIV/Aids remains among leading killers and prevention will always prevail over cure.
Dr Othieno is a veterinary doctor based in Nairobi. [email protected]