AspexBio Raises $120 Million to Accelerate AHB-137 Phase 3 and Commercialization
$120 Million to Simultaneously Support Late-Stage Development and Commercialization
The pre-IPO biotech companies AspexBio Therapeutics and AspexBio Pharma have completed a $120 million Series C equity financing round. Strategic investors led the round, with RA Capital Management joining as a new participant, followed by HanKang Capital, Chi Ming Venture Partners, Weyen BioVenture Capital, and CDH Investments. The company's cumulative fundraising since 2024 has now reached $360 million. The funds will be allocated to the China Phase 3 trial and commercialization preparation of AHB-137, as well as the development of AHB-171 and combination therapies. This financing aims to not only cover the cost of a single clinical trial but also to build manufacturing, regulatory, and market access capabilities, reflecting a valuation reassessment for a late-stage company.
AHB-137 Directly Inhibits HBV RNA and Antigen Production
AHB-137, an antisense oligonucleotide (ASO) without a brand or international nonproprietary name yet, is designed to bind to hepatitis B virus (HBV) RNA to reduce viral protein and surface antigen (HBsAg) production and inhibit DNA replication. In the Phase 2 trial NCT06829329 with treatment-naïve patients, 8 out of 25 patients (32%) achieved functional cure at 24 weeks post-treatment after 16 weeks of once-weekly monotherapy at 300 mg. At the end of treatment, 17 out of 25 patients (68%) achieved complete response, but one case of treatment-related serious adverse events was reported, including elevated ALT, bilirubin, and HBV DNA, highlighting liver safety as a key focus in later-stage trials. To accurately reflect clinical value, the patient numbers, evaluation timepoints, and safety results from the conference raw data should be considered instead of the previously summarized 72-week 30% functional cure and absence of serious adverse events.
The 577-Patient China Phase 3 Trial is Central to Company Value
The AUSHINE Phase 3 trial NCT07246889 is evaluating 577 HBeAg-negative chronic HBV patients in China using a randomized, double-blind design. The trial started in August 2025, with primary completion expected in December 2026 and full completion in October 2027, clearly defining the short-term use of Series C funds. Current standard-of-care treatments include Baraclude (entecavir, HBV DNA polymerase/reverse transcriptase inhibitor), Viread (tenofovir disoproxil), and Beqvez (tenofovir alafenamide), which strongly suppress the virus but do not provide long-term functional cure. Therefore, AHB-137's commercial differentiation hinges on demonstrating the durability of HBsAg loss and the potential to discontinue oral antiviral therapy in the Phase 3 trial.
Direct Competition with Bepirovirsen Has Already Begun
The most advanced competitor is GSK plc (GSK)'s Bepirovirsen sodium, a Phase 3 ASO targeting HBV transcripts, which does not yet have a commercial brand name. In the B-Well 1 and B-Well 2 trials, functional cure rates at 72 weeks were 127 out of 650 patients (20%) and 106 out of 570 patients (19%), respectively, with all placebo groups at 0%. In Japan, it was designated as a SAKIGAKE (pioneer) drug in August 2024, and a manufacturing and marketing application was submitted on February 26, 2026, though this is not yet approval or advisory committee decision. With 254 million chronic HBV-infected patients globally in 2022 and a projected $4.1 billion market in 2026, AHB-137 must demonstrate superior cure durability or dosing convenience compared to Bepirovirsen to secure a meaningful market share.
This $120 million equity financing enables AspexBio to execute its 577-patient China Phase 3 AUSHINE trial through primary completion in December 2026 and to build manufacturing and regulatory infrastructure in parallel. In Phase 2, AHB-137 monotherapy achieved 32% functional cure at 24 weeks post-treatment, but one treatment-related serious liver adverse event was reported, making response durability and ALT/bilirubin management key validation points for investigators. GSK plc (GSK)'s Bepirovirsen achieved 19–20% functional cure in two Phase 3 trials and entered Japan regulatory review in February 2026, giving it a commercialization timeline advantage. In the $4.1 billion chronic HBV market in 2026, short-term value will depend on AUSHINE data and regulatory progress, while mid-to-long-term value will hinge on whether AHB-171 Phase 1 siRNA and combination therapies can shift the entecavir/tenofovir-based lifelong treatment paradigm to a finite treatment approach.