Are we any closer to a cure?

It’s been 50 years since the first HIV-related death was recorded. The virus though continues to be a sly foe to the 38 million people worldwide living with the disease. But recently, a second patient appeared to be ‘cured’.

If any phenomenon has played an unsung role in medical discoveries, it is serendipity. One such chance occurrence has now buoyed the hope of scientists struggling for years to find the ‘holy grail’ of HIV research — a possible cure.

It is heartening to note that worldwide, treatment and management of HIV has improved dramatically over the past two decades and people living with the disease are able to live longer and manage the disease with one pill as opposed to a ‘cocktail of drugs’ at one point. However, HIV remains a global burden.

Stigma and ostracism continue to haunt sufferers, and in poorer countries, especially in Asia and Africa, the epidemic has remained the cruel adversary it always was.

Consider these numbers. According to UNAIDS 2018 figures, there are approximately 38 million people living with
the disease of which 36.2 million are adults and 1.7 million children. In 2018 alone, an estimated 1.7 million individuals were newly infected with the disease and the virus killed around a million people.

But first, the good news

However, there is considerable good news too. The number of Aids-related deaths has seen a huge drop of nearly 50 per cent from 2005 to 2017 worldwide. In India too, there has been a similar decrease with a 56 per cent decrease in deaths from 2010 to 2017. The number of new HIV infections in India also reduced from 1,20,000 to 88,000 in the same period.

This number crunching is important because it not only reveals the extent to which global HIV/Aids awareness campaigns have succeeded but also affirms the greatly improved efficacy of the Anti-Retroviral Treatment (ART).

In fact, so efficient is the treatment now that opinion is divided in the medical community about whether the research ought to focus on finding a cure or if the same money could be better utilised by making ART accessible to more people.

“When I treated my first HIV patient way back in 1989, all we talked about was suffering and dying. Today, the atmosphere in my clinic is so positive — some of my HIV patients have lived longer than those suffering from other chronic diseases like diabetes and hypertension,” says Dr K S Satish, senior consultant pulmonologist at the Fortis Hospitals, Bangalore, who has had 30 years of experience in the field of HIV medicine and has been part of several clinical trials.

No longer a death sentence but...

Having said that, the doctor cautions that though HIV has ceased to be a ‘death sentence’ as it were, when medications are not taken or when people do not have constant access to the pill, the risk of the virus rapidly taking over the infected body is real and alive.

As Consultant Physician Dr Shylaja Shyamsundar, who has long been treating HIV-infected patients at BGS Gleneagles Global Hospital, Bangalore, says, unlike other viruses, HIV-infected cells can ‘hide’ and be virtually invisible to the body’s immune system and treatment therapies. “Stop the pill and they come out of hiding and begin multiplying in billions. Not only that, they also turn mutant — which is why complete compliance to the treatment is critical.”

What ART does, explain the doctors, is suppress the multiplying of the virus; in other words, it keeps the devil under check but cannot (and does not) eliminate it.

It is precisely because ART cannot kill the virus that eminent researchers like Prof John Frater of the University of Oxford are advocating for “not taking the hunt for a cure off the HIV agenda”.

And with the unexpected discovery of a possible path to a cure, a surcharge of hope has run through the HIV/Aids research community, struggling for years to find a breakthrough.

What happened with the London patient?

Breaking down the complex procedures that led up to this discovery, Dr Satish explains how an infected person in the UK, identified only as the “London patient” was declared ‘cured’ a few months earlier this year. “This ‘London Patient’ was diagnosed with HIV in 2003 and in 2012, it was discovered he had advanced Hodgkin lymphoma, the cancer of the immune system.

The only way to treat him was through intense chemotherapy and a bone marrow transplant containing stem cells to rebuild his immune system. Doctors selected a donor with a rare genetic mutation that granted him resistance to HIV and thus the London patient’s immune system was rebuilt with HIV resistant cells.”

A shift in focus

A decade earlier, exactly this procedure had been applied on another patient Timothy Ray Brown and he is today free of HIV. Curiously enough, researchers had failed many times to replicate the procedure on others till they finally found success with the London patient. (This is also why they are still to completely understand what exactly worked this time around.)

Dr Shylaja adds that in March this year, doctors who treated the London patient announced that it has been 18 months since the HIV virus has been undetectable in his body and thus he could be considered ‘cured’.

In fact, with this unexpected success, the focus of the research has shifted subtly to these aforementioned ‘hiding’ cells. Technically known as ‘latently-infected’ cells, these are the ones researchers are now looking to destroy to find the all-elusive cure. While some researchers are using the ‘shock and kill’ approach wherein they are trying to bring these hiding cells out in the open so that they can be eliminated, others are looking for ways to destroy them while they are in hiding itself.

Gene therapy to the rescue?

The exciting part is of course how they are planning to conduct this guerilla warfare —through gene therapy and gene editing — the ‘sexiest’ areas of medical research today.

Evidently, as far as a cure for HIV/Aids is concerned, it is hope that ought to be garnished with a dose of realism. As some researchers put it, with the new successes, they have traversed a journey from mere aspiration to solid feasibility. And that itself has been a long and hard road.