On-treatment prediction of sustained response to peginterferon alfa-2a for HBeAg-negative chronic hepatitis B patients

Background & AimsWe assessed predictors of response in HBeAg-negative chronic hepatitis B patients treated with peginterferon alfa-2a in routine clinical practice. MethodsNinety-five HBeAg-negative patients received peginterferonalfa-2a for 48weeks and were followed-up for 48weeks post-treatment. Serum HBsAg and HBV DNA levels were monitored during and after therapy with valid commercial assays. Sustained response (SR) was defined as HBV DNA <2000IU/ml at study week 96. ResultsTwenty-two patients (23%) achieved SR and nine (9.5%) lost HBsAg. HBsAg decline was more profound in patients with SR. HBsAg decline 10% from baseline to week 24 was significantly associated with SR [81% (17/21) vs 37% (21/57); Odds ratio: 7.286 (2.162-24.552), P=0.001]. The PARC rule (no decrease in HBsAg and <2 log drop in HBV DNA at week 12) was evaluated in a subset of 47 patients. Among eight patients who fulfilled the PARC rule, none achieved SR. Of the 39 patients who did not fulfil the PARC rule, 24 (62%) had HBsAg decline of 10% at week 24 (12 achieved SR) and 15 (38%) had HBsAg decline of <10% (1 achieved SR; negative predictive value: 93%). ConclusionsIn HBeAg-negative chronic hepatitis B patients treated with peginterferon alfa-2a, HBsAg decline >10% at 24weeks is significantly associated with SR. The combination of the PARC rule and week 24 decline in HBsAg can identify almost two-thirds of patients who are unlikely to achieve SR. Clinicaltrials.gov identifier: NCT01283074.