Q&A: Finding a cure for hepatitis B
The NIH announced a plan to “intensify” ongoing hepatitis B virus research that is focused on finding a cure and improving screening and treatment for the infection.
For nearly 40 years, there has been an effective vaccine to prevent HBV, but the virus still causes an increasing number of illnesses and deaths worldwide each year. Focusing on three critical research areas, the Strategic Plan for Trans-NIH Research to Cure Hepatitis B aims to address the global public health challenge that HBV presents.
Healio spoke with National Institute of Allergy and Infectious Diseases Director Anthony S. Fauci, MD, about the plan, the “crucial” role that clinicians play, and how close the world is to a cure for HBV. – by Marley Ghizzone
Q: What was the impetus for the plan?
A: Hepatitis B is a prevalent and serious disease. The global disease burden is approximately 257 million chronic infections worldwide — 850,000 to 2.2 million in the United States — and approximately 900,000 deaths per year, with those numbers increasing.
There are new scientific opportunities to pursue due to the identification of a cell receptor for HBV, more advanced cell culture systems and the identification of major steps of virus replication.
In October 2018, the Congressional Appropriations Committee report requested the NIAID-led Trans-NIH Working Group to coordinate research agendas and infrastructure to find a cure for HBV.
In early 2019, the NIH Working Group included NIAID, the National Institute of Diabetes and Digestive and Kidney Diseases, the National Cancer Institute, the National Institute on Minority Health and Health Disparities and the NIH Office of the Director.
From February to March 2019, the NIH put out a request for information to solicit comments on plan structure. It received 34 responses from academia, private companies and government organizations.
Q: What does it focus on?
A: Priority one is to understand hepatitis B biology by identifying viral factors that control infection and disease, understanding immune and other host factors of HBV infection and characterizing clinical pathology and factors that affect disease progression.
Priority two is to develop tools and resources by standardizing and sharing reagents, procedures and assays; improving and creating in vitro and animal models that reflect human liver disease; establishing biomarkers and diagnostics for disease progression and response to therapy; and expanding clinical research capacity.
Priority three is to create strategies to cure and prevent hepatitis B by advancing strategies that suppress viral replication and/or stimulate the immune response, evaluating curative approaches in various subpopulations and improving strategies to screen, link to care or vaccinate high-risk and underserved populations.
Q: Is there a role for clinicians?
A: Clinicians play a crucial role to ensure HBV research captures the complexities of the disease and asks and answers questions that are directly relevant to the patient population
Scientists and clinicians collaborate to conduct clinical studies that validate laboratory findings, identify new biomarkers, evaluate therapeutic strategies and develop improved diagnostics.
Clinicians are essential to improve vaccination rates, especially in underserved populations.
Q: Why is there a cure for hepatitis C and not hepatitis B?
A: There is no simple answer to this. Hepatitis C and hepatitis B are caused by entirely different types of viruses, which carry RNA and DNA genomes, respectively. Each interacts differently with the hepatocyte (liver cell) and has vastly different mechanisms of replication. HBV has a sophisticated, self-perpetuating mechanism that is very difficult to target with drugs.
Immune responses against these two viruses are also very different — hepatitis B can be prevented with a very effective vaccine, whereas 30 years of effort have not yet led to a vaccine against hepatitis C.
Challenges to curing hepatitis B are far greater because of the nature of replication of HBV and its mechanisms of persistence.
Q: How close is the world to a cure for HBV , and what would that look like?
A: New advances are fueling the race toward a cure for hepatitis B, and the outlook for new and better drugs in the next several years is promising.
A “functional” cure would be marked by — after completion of a finite course of treatment — a sustained loss of hepatitis B virus surface antigen (HBsAg), undetectable HBV DNA in serum and preferably with antibodies against HBsAg.
Disclosure: Fauci reports no relevant financial disclosures.