Ambrx Biopharma Inc's (NYSE:AMAM) partner in China, NovoCodex Pharmaceuticals Ltd, presented favorable safety and efficacy data from its ongoing ACE-Breast-01 Phase 1 study of ARX788 at the San Antonio Breast Cancer Symposium (SABCS).

• ARX788 demonstrated treatment effect among patients who previously failed a median of seven anti-HER2 targeting therapies.
• ARX788 demonstrated robust anti-tumor activity, with a disease control rate of 100% in the 29 patients treated at 1.5 mg/kg Q3W.
• One patient who received prior pertuzumab also achieved confirmed partial response (PR).
• The disease control rate among evaluable patients in the 1.5 mg/kg cohort was 100% (29/29).
• ARX788 demonstrated low systemic toxicity and was generally well-tolerated, with most adverse events being grade 1 or 2. No dose-limiting toxicity or drug-related deaths occurred.
• Price Action: AMAM shares are up 11.50% at $9.18 during the market session on the last check Thursday.