Factors predictive of sequential nucleos(t)ide analogue, IFN-α therapy response identified
Published on March 13, 2015 at 5:15 PM · No Comments
By Shreeya Nanda, Senior medwireNews Reporter
Hepatitis B surface antigen (HBsAg) and hepatitis B core-related antigen (HBcrAg) levels can predict long-term response to sequential nucleos(t)ide analogue and interferon-α (IFN-α) therapy in patients with chronic hepatitis B virus (HBV) infection, research indicates.
Researcher Eiji Tanaka (Shinshu University School of Medicine, Matsumoto, Japan) and colleagues also report that maximal levels of alanine aminotransferase (ALT) and HBV DNA during follow-up could be useful for monitoring response to sequential treatment.
This retrospective study included 50 chronic HBV patients treated with a nucleos(t)ide analogue plus IFN-α for 4 weeks followed by IFN-α alone for 20 weeks, with the aim of identifying “factors associated with a long-term response to IFN-α sequential therapy in order to safely discontinue [nucleos(t)ide analogue] therapy”.
After a follow-up of 24 months, 18 participants had serum HBV DNA lower than 4.0 log copies/mL, serum ALT below 30.0 IU/L and were negative for hepatitis B e antigen (HBeAg), and as such were deemed as responders. The remaining 32 did not fulfil these clinical criteria and were classified as nonresponders.
Multivariate analysis showed that individuals with HBsAg levels of 3.0 log IU/mL or higher and HBcrAg levels of 4.5 log U/mL or higher when IFN-α treatment was initiated were significantly less likely to respond to sequential therapy at 24 months than individuals with lower levels.
And receiver operating characteristic (ROC) analysis revealed a significant association between treatment response and maximal ALT and HBV DNA levels, with area under the curve values of 0.839 and 0.868, respectively.
The researchers identified cutoff values of 128 IU/L for ALT and 6.0 log copies/mL for HBV DNA levels, such that patients with levels greater than these during post-treatment follow-up were “likely to be non-responders”.
Using the ALT cutoff to define relapse, they found that most instances of relapse occurred during the initial 24 weeks after IFN-α treatment was stopped, a time period generally considered to be an appropriate monitoring time, they note.
“Accordingly, patients who are likely to be non-responders can now be identified as early as 24 weeks in advance and alternative strategies for treatment may be considered in a more timely fashion”, the team concludes in Hepatology Research.