Quest Diagnostics has launched a new hepatitis B virus surface antigen quantitative testing service for evaluating response to treatment.
HBsAg qualitative testing is currently used to help diagnose HBV, but this new service will assess the quantity of viral antigen in blood to help determine if an HBV patient’s immune system is responding to treatment.
“With this insight, physicians are better positioned to monitor response to antiviral medications, and may enable them to modify or adjust treatment to help minimize the likelihood of progression and reactivation,” according to a press release. In it, the company also cited a study published last year in Hepatology whose researchers noted that “HBsAg is essential to monitor the response to new therapeutic concepts.”
“The widespread availability of quantitative HBsAg testing through Quest for use by hepatologists, gastroenterologists and other specialists will advance the care of HBV-infected patients,” Robert G. Gish, MD, of Robert G. Gish Consultants, said in the press release. “The ability to reliably quantify surface antigen will enhance clinicians’ ability to stage patient’s disease state, provide prognostic information and help guide care with current antivirals and new therapies that are in the development pipeline.”
While direct acting antivirals have high success rates in hepatitis C virus infection, HBV cure rates are lower because the virus is persistent and compliance with long-term therapies is low, according to the press release. Further, viral load can be suppressed during treatment, so it cannot signal viral clearance on its own, and thus the AASLD defines chronic HBV resolution by clearance of HBsAg.
“An estimated 850,000 to 2.2 million persons in the U.S. are infected with chronic hepatitis B,” Rick L. Pesano, MD, PhD, vice president of research and development at Quest Diagnostics, said in the press release. “While there are effective therapies that can functionally cure HBV infection, physicians in the U.S. have lacked tools that help predict individualized patient response to those treatments. With this new test capability, physicians can better develop tailored treatment plans and monitor HBV-infected patients to help prevent progression and better their chance for long-term immunity.”