Diagnosis and research key to hepatitis elimination
In 2017, global virus elimination is the focus of World Hepatitis Day. Hepatitis C was first identified in 1989 and today we have drugs that destroy the virus. Associate Director of the MRC-University of Glasgow Centre for Virus Research Professor John McLauchlan’s work contributed to this transformation. The real challenge now, he writes, is diagnosis.
This is my third blog post to mark World Hepatitis Day. In 2013 I shared our plans to help the NHS deliver the best treatment to patients through two research consortia, HCV Research UK and STOP-HCV. In 2015 I wrote about the impact of new anti-viral drugs, able to not just control the virus, as is the case for HIV, but rid people of their infection.
Thanks to new treatments, many people are now at a much lower risk of developing liver disease and there are reports of patients who no longer require a liver transplant.
Today, most people infected with hepatitis C receiving the new therapies can expect to have the virus wiped from their blood. The biggest challenge we now face is continuing to diagnose those unaware that they carry the virus.
To truly eliminate hepatitis C, we need to find people in communities around the world living with infection. Especially those in low- and middle-income countries lacking the infrastructure of the more developed nations.
We predict there are as many as 170 million people infected with hepatitis C. In the UK around 50% of people infected are diagnosed. The other 50% don’t know they carry the virus and, even if they are diagnosed, will not necessarily have access to treatment.
For elimination of the virus on a global scale, the difficulty is a lack of resources. Many countries in Africa and Asia for example do not have the same treatment or diagnostic provisions that we have in the UK and this magnifies the problem. It makes the goal of eradicating hepatitis C by 2030, an objective of the World Health Organization, a huge challenge.
A changing beast
Then there is the virus itself. Hepatitis C is one of the most variable pathogens known to infect humans. Its genetic makeup is very changeable, for example there are seven known ‘genotypes’ divided into further ‘sub-types’. One individual alone can be infected with multiple strains. We’re still finding new types and I expect there are more out there.
Identifying the virus type means that people can be treated with the correct classes of drug. This increases the chance of completely removing the virus from the patient’s blood. At least two classes of drugs need to be used in combination to maximise successful treatment. For some classes of drug, there are many options available that act in different ways depending on the genetic makeup of the virus.
Having a set of drugs that work effectively against such a variable virus is mind-blowing. The drugs are still being improved to make them ever more powerful against the virus. The aim is to have drugs that are equally effective against all types of the virus.
A challenge for the future though, is helping treat people in whom the virus is not successfully killed by drugs. This is usually due to resistance that hepatitis C develops against the drugs. Identifying how the virus develops resistance is an important research question which will help guide clinicians on retreatment choices. This may mean changing the class of drug used or prescribing a more powerful drug.
We also need to know what happens to people after successful treatment. This requires long-term studies to monitor people for any liver disease that occurs because of previous infection with the virus. We predict that cases of liver disease caused by hepatitis C infection will go down as more people are diagnosed and treated.
Where there’s a will
Having the means to eliminate hepatitis C is a fantastic success story dating back through the 1990s and early 2000s. Basic science made all of the necessary progress to allow the development of new drugs – drugs that are now becoming the standard of care in the clinic. People infected with the virus, and the clinicians who treat them, are now reaping the benefits of that work.
In the UK, funding bodies such as the Medical Research Foundation and the MRC have invested heavily from charitable donations and the public purse. The result is clinical and scientific networks that provide solutions for infections that pose a huge burden on our healthcare services and individuals.
More research is needed to address the remaining challenges. Further funding for research is vital to support this important work. But achieving elimination of hepatitis C here in the UK, and elsewhere, is now possible and within our grasp – we just need the will to do it!
STOP-HCV is funded by the MRC. HCV Research UK was established through funding from the Medical Research Foundation (MRF). Look out for £1.5m of funding opportunities, for emerging research leaders working on viral hepatitis, being launched later this year by the MRF. For more information contact email@example.com