Abbisko Announces Updated Irpagratinib Data in HCC: Best Poster of ESMO 2024

SHANGHAI, Sept. 18, 2024 – Abbisko Therapeutics (HKEX: 02256) proudly announced receiving the ESMO 2024 Best Poster Award on September 16, 2024. The accolade was awarded for their presentation titled "Updated Safety and Efficacy of Irpagratinib (ABSK011) in advanced hepatocellular carcinoma (aHCC) with FGF19 overexpression from a Phase 1 study". The updated data from the ABSK-011-101 study indicated that Irpagratinib showed a manageable safety profile and promising anti-tumor activity as a monotherapy in aHCC. Significantly, among patients with aHCC who had been pretreated with both immune checkpoint inhibitors (ICI) and Tyrosine Kinase Inhibitors (TKI)—a group with considerable unmet treatment needs—the observed Objective Response Rate (ORR) and Disease Control Rate (DCR) were 44.8% and 79.3%, respectively. Additionally, the median duration of response (mDoR) was 7.4 months, and the median progression-free survival (mPFS) was 5.5 months.

At the 2024 ESMO Congress, the poster numbered #983P was showcased during the Hepatocellular Carcinoma poster session on Sunday, September 16, 2024. The Best Poster Award was conferred at the end of the session, with only one recipient honored in the HCC poster session.

As of September 5, 2024, the study had enrolled 122 patients, including 74 in the BID cohort with doses of 160mg BID, 220mg BID, and 300mg BID. The patient demographics showed that 5.4% were at BCLC Stage B, 89.2% at BCLC Stage C, with Child-Pugh (CP) Scores of 5 (64.9%), 6 (27%), and 7 (6.8%). A significant 64.9% of patients had undergone multiple lines of prior therapy, 85.1% had received prior ICIs, and 75.7% had been treated with both ICIs and mTKIs.

Efficacy data revealed that among forty pre-treated HCC patients with FGF19 overexpression who were administered irpagratinib at 220 mg BID, the response rate was 36.8% (14/38) among the 38 evaluable patients. The disease control rate (DCR) was 78.9% (30/38). In the subset of patients who had previously received ICI and mTKI therapy, the response rate was 44.8% (13/29). The longest observed duration of response (DoR) was 16.4 months, with a median DoR of 7.4 months. The DCR was 79.3% (23/29) and the mPFS was 5.5 months.

Safety data indicated that one dose-limiting toxicity (DLT) was observed in the 300 mg BID cohort. The most common treatment-related adverse effects (>20%) included elevated ALT, diarrhea, elevated AST, hyperphosphatemia, elevated bilirubin, increased alkaline phosphatase, decreased platelet count, and elevated total bile acid. Grade 3-4 treatment-related adverse events (>5%) consisted of elevated AST, elevated ALT, and diarrhea. No Grade 5 adverse events were reported.

Hepatocellular carcinoma (HCC) is the predominant form of liver cancer, comprising 85% to 90% of primary liver cancers. HCC is highly malignant, with about 30% showing abnormally high FGFR4 expression and consequently poor prognosis. Current treatments are insufficient for long-term survival benefits. There is no approved standard of care for HCC patients who have progressed after first-line ICI-based therapies. The FGF19/FGFR4 signaling axis is a potential novel therapeutic target for HCC. Irpagratinib (ABSK011), a potent FGFR4 inhibitor, has demonstrated a tolerable safety profile and promising anti-tumor activity as a single agent. The 220mg BID regimen of irpagratinib showed a 44.8% ORR, a 7.4 months mDoR, and a 5.5 months mPFS in heavily pre-treated HCC patients, supporting further late-stage development of the drug for populations with significant unmet medical needs.

Additionally, Abbisko Therapeutics has presented the design of the phase II study of pimicotinib in combination with chemotherapy, with or without toripalimab, as a first-line treatment for advanced pancreatic ductal adenocarcinoma (PDAC).

Irpagratinib (ABSK011) is a highly selective FGFR4 small molecule inhibitor designed for treating advanced solid tumors with abnormalities in the FGF19/FGFR4 signaling pathway, including advanced HCC, cholangiocarcinoma, and breast cancer. The FGFR4 signaling pathway is recognized as a promising target for HCC treatment. Clinical data for irpagratinib have shown improved potency and anti-tumor efficacy compared to competitors.

Founded in April 2016, Abbisko Therapeutics Co., Ltd., a subsidiary of Abbisko Cayman Limited (Stock Code on the Hong Kong Stock Exchange: 2256.HK), is an oncology-focused biopharmaceutical company based in Shanghai that is dedicated to discovering and developing innovative medicines to meet unmet medical needs both in China and globally. The company, established by seasoned professionals from leading multinational pharmaceutical companies, has developed a broad pipeline of 16 innovative small molecule programs focused on precision oncology and immuno-oncology.