GSK entered an exclusive collaboration agreement, through its subsidiary Chia Tai Tianqing Pharmaceutical Group (CTTQ), with Sino Biopharmaceutical (SBP Group) to advance Bepirovirsen during its launch.

The partnership aims to accelerate Bepirovirsen’s launch in mainland China using CTTQ’s broad commercial footstep that spans across more than 5000 medical centers.¹

What is Bepirovirsen?

Bepirovirsen is a triple-action antisense oligonucleotide licensed from Ionis that works by inhibiting viral DNA replication, suppressing hepatitis B surface antigen in the blood, and stimulating the immune system to mount a durable response.¹ It was designed to address the central limitation of current standard-of-care treatments, typically nucleos(t)ide analogues, which require lifelong therapy and achieve functional cure rates of only around 1%.

Functional cure, defined as undetectable hepatitis B virus DNA and surface antigen for at least 24 weeks after stopping treatment, is associated with a significant reduction in the risk of long-term complications including liver cancer. Achieving it at meaningful rates would represent a transformative advance for a disease affecting more than 250 million people worldwide and causing approximately 1.1 million deaths annually.

What are the details of the collaboration?

Under terms of the agreement, CTTQ is set to handle importation, distribution, hospital access, and promotional activities across its network of more than 5,000 medical centers, while GSK retains the marketing authorization and responsibility for regulatory, quality, pharmacovigilance, and global medical strategy.¹

GSK is also expected to book sales of Bepirovirsen supplied to CTTQ under the initial 5.5-year agreement. The deal will also grant GSK the ability to review certain early-stage pipeline assets from the SBP Group for potential collaboration outside China.

China's hepatitis B burden is among the most severe globally, with an estimated 75 million people affected, approximately 450,000 deaths annually, and 84% of liver cancer cases in the country associated with chronic hepatitis B infection.¹ The Chinese government's National Action Plan for the Prevention and Treatment of Viral Hepatitis (2025-2030) has explicitly set functional cure as a treatment goal.

"By combining GSK's innovation with CTTQ's extensive local scale and execution, we want to reach more patients, deliver greater impact, and directly address one of China's most pressing healthcare priorities," said Mike Crichton, president international at GSK.

What is the FDA's position on Bepirovirsen?

In April, 2026, FDA accepted a New Drug Application for Bepirovirsen for the treatment of adults with chronic hepatitis B along with granting it both Priority Review and Breakthrough Therapy Designation.² The agency also assigned October 26, 2026, as the PDUFA action date.

The Breakthrough Therapy Designation, reserved for drugs showing preliminary evidence of substantial improvement over available therapies, builds on a Fast Track Designation granted in February 2024 and enables greater FDA guidance on the development program.¹

The regulatory submission is supported by Phase III results from the B-Well 1 and B-Well 2 trials, in which Bepirovirsen demonstrated statistically significant and clinically meaningful functional cure rates compared to standard of care alone across all ranked endpoints, including a particularly pronounced effect in patients with lower baseline hepatitis B surface antigen levels.² The safety and tolerability profile remained consistent with prior studies, with full data expected to be presented at the European Association for the Study of Liver Congress and submitted for peer-reviewed publication in 2026.²

Sources

1. GSK enters exclusive collaboration with SBP Group, a market leader in hepatology in China, to accelerate bepirovirsen at launch GSK May 11, 2026 https://www.gsk.com/en-gb/media/press-releases/gsk-enters-exclusive-collaboration-with-sbp-group-a-market-leader-in-hepatology-in-china-to-accelerate-bepirovirsen-at-launch/?sessionid=
2. Bepirovirsen accepted for priority review and granted Breakthrough Therapy Designation by the US FDA GSK April 28, 2026 https://www.gsk.com/en-gb/media/press-releases/bepirovirsen-accepted-for-priority-review-and-granted-breakthrough-therapy-designation-by-the-us-fda/