Clinical Utility of SCALE-B to Predict Hepatitis B Virus Relapse, Hepatitis B Surface Antigen Loss After Antiviral Cessation in Asian Patients After 2-Year Follow-up

Apichat Kaewdech; Suraphon Assawasuwannakit; Pimsiri Sripongpun; Naichaya Chamroonkul; Pisit Tangkijvanich; Teerha Piratvisuth

doi:10.3389/fmed.2022.859430

Clinical Utility of SCALE-B to Predict Hepatitis B Virus Relapse, Hepatitis B Surface Antigen Loss After Antiviral Cessation in Asian Patients After 2-Year Follow-up

Front Med (Lausanne). 2022 Mar 24:9:859430. doi: 10.3389/fmed.2022.859430. eCollection 2022.

Authors

Apichat Kaewdech¹, Suraphon Assawasuwannakit^{1

2}, Pimsiri Sripongpun¹, Naichaya Chamroonkul¹, Pisit Tangkijvanich^{3

4}, Teerha Piratvisuth^{1

5}

Affiliations

¹ Gastroenterology and Hepatology Unit, Division of Internal Medicine, Faculty of Medicine, Prince of Songkla University, Hat Yai, Thailand.
² Department of Medicine, Panyananthaphikkhu Chonprathan Medical Center, Srinakharinwirot University, Nonthaburi, Thailand.
³ Department of Biochemistry, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
⁴ Center of Excellence in Hepatitis and Liver Cancer, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
⁵ NKC Institute of Gastroenterology and Hepatology, Songklanagarind Hospital, Prince of Songkla University, Hat Yai, Thailand.

Abstract

Background: Discontinuation of antiviral therapy in chronic hepatitis B (CHB) patients leads to a higher hepatitis B surface antigen (HBsAg) loss; yet, clinical relapse (CR) may occur. SCALE-B score was developed to predict off-treatment CR; however, validation of SCALE-B beyond a 48-week follow-up is rare. We studied whether SCALE-B and hepatitis B virus ribonucleic acid (HBV RNA) could predict outcomes in CHB patients after a 2-year follow-up.

Methods: A total of 92 Thai CHB patients who stopped antiviral treatment were followed up; baseline characteristics, quantitative hepatitis B surface antigen (qHBsAg), hepatitis B core-related antigen (HBcrAg), and HBV RNA were collected at the time of discontinuation, and SCALE-B scores were calculated. Patients were followed up every 12 weeks for 48 weeks, and then, the intervals were upon primary doctors. Follow-up data regarding virological relapse (VR), CR, and HBsAg loss were obtained.

Results: The median follow-up duration was 142 weeks; the cumulative incidences of VR, CR, and HBsAg loss were 65.2, 33.7, and 7.6%, respectively. After 48 weeks, VR and CR plateaued, but HBsAg loss increased from 2.2 to 7.6%. According to the SCALE-B strata, VR, CR, and HBsAg loss were significantly different. The highest stratum (≥ 320) was associated with higher VR, CR, and lesser HBsAg loss when compared to the lowest stratum, with adjusted hazard ratios of 5.0 (95% CIs: 1.8-14.4), 10.44 (95% CIs: 1.4-79.1), and 0.04 (95% CIs: 0.004-0.43), respectively.

Conclusion: At a median follow-up of 2.5 years after discontinuing therapy, HBsAg loss in Thai patients was found to increase over time. SCALE-B is a valuable tool for predicting CR, VR, and HBsAg loss; HBV RNA is not significantly associated with long-term outcomes.

Clinical trial registration: [www.ClinicalTrials.gov], identifier [TCTR20180316007].

Keywords: S-loss; SCALE-B; cessation; clinical relapse (CR); hepatitis B core-related antigen (HBcrAg); hepatitis B surface antigen (HBsAg); hepatitis B virus ribonucleic acid (HBV RNA); nucleos(t)ide analogues (NAs).