Handok 'HD-B001A' Biliary Tract Cancer Phase 2 Key Results Presented at ASCO GI

Bispecific Antibody Licensed from ABL Bio

'Handok Future Complex' and 'Genexine Progen Bio Innovation Park'
[Photo by Handok]

[Asia Economy Reporter Chunhee Lee] Handok announced on the 20th (local time) that the key results of the Phase 2 clinical trial of 'HD-B001A (CTX-009, ABL001)' for cholangiocarcinoma patients will be presented as a poster at the American Society of Clinical Oncology Gastrointestinal Cancer Symposium (ASCO GI 2023) held in San Francisco, USA.

HD-B001A is a next-generation anticancer drug being developed using bispecific antibody platform technology. Handok holds domestic rights through a licensing agreement with ABL Bio and has been conducting a domestic Phase 2 clinical trial focusing on cholangiocarcinoma since 2021. Based on the domestic trial, Handok is laying the groundwork for expanding HD-B001A into global clinical trials and is collaborating with Compass Therapeutics on clinical trials in the United States.

According to the 2020 National Cancer Registry statistics, the 5-year survival rate for cholangiocarcinoma is 28%, the second lowest among major cancers after pancreatic cancer (13.9%). Only 10% of cholangiocarcinoma cases are detected at an early stage where surgical resection is possible. The majority are diagnosed at locally advanced or progressed stages, with very limited treatment options.

This Phase 2 trial was conducted at four domestic institutions, including Seoul National University Hospital, targeting patients with unresectable advanced, metastatic, or recurrent cholangiocarcinoma who had previously received first- or second-line systemic chemotherapy. In the primary efficacy evaluation of 24 participating patients, the objective response rate (ORR) for the combination therapy of HD-B001A and paclitaxel was 37.5%, with 9 partial responses (PRs) observed. Among 11 patients treated as second-line therapy, 7 showed partial responses, resulting in an ORR of 63.6% for second-line treatment.

After 12 months of follow-up, the median progression-free survival (mPFS) was 9.4 months, and the median overall survival (mOS) was 12.5 months. For comparison, the average mPFS and mOS for FOLFOX-based therapy, which is recommended by the National Comprehensive Cancer Network (NCCN) guidelines for patients with advanced cholangiocarcinoma, are known to be 4 months and 6.2 months, respectively. Additionally, the incidence of grade 3 or higher treatment-emergent adverse events (TEAEs) in the Phase 2 trial was 95.8%, regardless of causality with HD-B001A or paclitaxel. Reported adverse events included neutropenia, hypertension, anemia, and thrombocytopenia.

Youngjin Kim, Chairman of Handok, stated, “At this ASCO GI, HD-B001A attracted significant attention from researchers and patients as a new treatment for advanced cholangiocarcinoma with high unmet needs. Handok and Compass Therapeutics will secure additional efficacy and safety data in global Phase 2 and 3 trials involving more patients based on the Korean Phase 2 trial.”

Handok is collaborating with Compass Therapeutics for global Phase 2 and 3 trials. Based on the results of these trials, HD-B001A is planned to be submitted for biologics approval in 2024. In addition to cholangiocarcinoma, a Phase 2 clinical trial for a colorectal cancer treatment is also underway.