Adagene Inc. announced data from its presentation at the American Society of Clinical Oncology (ASCO) 2024 Gastrointestinal (GI) Cancers Symposium, taking place January 18-20 in San Francisco. Key highlights from the poster (November 30, 2023 data cutoff) include: Results from dose escalation and dose expansion cohorts of ADG126 in combination with Merck & Co. Inc., Rahway, NJ, USA?s anti-PD-1 therapy KEYTRUDA® (pembrolizumab) (200 mg/Q3W) demonstrated a best-in-class safety profile for ADG126 at doses from 6 mg/kg to 10 mg/kg in heavily pre-treated advanced/metastatic patients (N=46): Limited dose-dependent toxicities were observed.

Grade 3 TRAEs occurred in 5/46 patients (10.8%), with no Grade 4 or 5 TRAEs and a discontinuation rate of 6.5% (3/46). In dose escalation across tumor types, two partial confirmed responses (PRs) were observed among the three patients treated with ADG126 10 mg/kgQ3W, which triggered expansion cohorts at this dosing regimen. One of the patients had PD-1 refractory cervical cancer and the other had endometrial cancer.

Both confirmed PRs are sustained after more than 55 weeks (over 14 cycles) of treatment. In dose expansion of patients with MSS CRC, 12 evaluable patients without liver metastases were treated at the active, potent dose of 10 mg/kg Q3W: Two confirmed PRs were observed in nine of these patients without peritoneal and liver metastases, resulting in an overall response rate of 22% in this subset. An additional seven of these nine patients experienced stable disease (SD) for an overall disease control rate 100% (2 PRs and 7 SD).

Observation of these clinical activities triggered further expansion into Stage 2 of the Simon?s 2-stage design for this dose level, which is currently ongoing with data anticipated throughout 2024. In a preliminary PFS analysis of those MSS CRC patients free of liver and peritoneal metastasis, a median PFS of seven months was observed in those treated with ADG126 10 mg/kg at two dosing frequencies pooled together [every three weeks (n=9) and every six weeks (n=6)]. The durable clinical activity of ADG126 in combination with pembrolizumab will continue to be evaluated as a larger cohort of subjects becomes evaluable at the 10 mg/kg Q3W dose level.