Xingyao Kunze Secures Second Breakthrough Therapy Designation for Hepatitis B siRNA Therapy HT-101 in Combination with Neutralizing Antibody HT-102

▎Armstrong

On September 15, 2025, Hepa Thera's HT-101 (HBV siRNA) + HT-102 (HBV neutralizing antibody) combination therapy for chronic hepatitis B infection is proposed to be included in the breakthrough therapy designation program. This marks the second time HT-101 has been included in the breakthrough therapy designation.

In July this year, HT-101 monotherapy for chronic hepatitis B virus infection has been included in the breakthrough therapy drug program.

Hepa Thera Focuses on Innovative Drug Development for Liver Diseases, with HT-101 and HT-102 as Its Leading Pipeline Products.

HT-101 is an siRNA therapy for hepatitis B, targeting the S antigen to inhibit HBV replication and reduce HBV antigens. HT-102 is a hepatitis B neutralizing antibody targeting HBsAg.

In March this year, Hepa Thera disclosed the Phase I clinical data of HT-101 at the APASL 2025 conference. Two injections significantly reduced HBsAg; the 400mg high-dose group showed a maximum reduction of 3.29 log. After 16 weeks of treatment, HBsAg levels in all six patients dropped below 100 IU/ml, with four patients maintaining levels below 10 IU/ml up to week 48.

Summary

Chinese small nucleic acid companies are transitioning from followers to leaders. While the overall development of siRNA for hepatitis B has faced challenges globally, companies such as Hepa Thera, Bowang Pharmaceutical, and Hengrui Medicine have successively achieved excellent clinical data with their hepatitis B siRNA drugs, qualifying them for breakthrough therapy designation, and have advanced into phase II clinical trials.