ARX788 HER2 ADC Drug Description

ARX788 is an antibody drug conjugate or ADC being developed by Ambrx Inc. The trial drug targets HER2 over-expressing tumors including breast, gastric, colon, pancreatic and ovarian cancers. ARX788 is based on Ambrx next-generation ADC technology platform whereby a HER2 specific monoclonal antibody is site-specifically conjugated with Amberstatin269, a potent cytotoxic tubulin inhibitor.

ARX-788 is Potential Best-In-Class Phase I Anti-HER2 ADC for the treatment of R/R Metastatic Breast Cancer that incorporates non-natural amino acid. The investigational drug is currently in clinical trials. The drug's payload is Amberstatin269 or AS269, a proprietary micro tubule inhibitor. The conjugation of Amberstatin269 to anti-HER2 antibody is site-specific and quantitative with a drug-to-antibody ration (DAR) = 1.9.
ARX-788 is Potential Best-In-Class Phase I Anti-HER2 ADC for the treatment of R/R Metastatic Breast Cancer that incorporates non-natural amino acid. The investigational drug is currently in clinical trials. The drug’s payload is Amberstatin269 or AS269, a proprietary micro tubule inhibitor. The conjugation of Amberstatin269 to anti-HER2 antibody is site-specific and quantitative with a drug-to-antibody ration (DAR) = 1.9. Image Courtesy Ambrx.

In preclinical settings, ARX788 has demonstrated an improved efficacy and safety profile relative and a wider therapeutic index compared to currently available HER2 targeting antibody-drug conjugates using conventional non-specific conjugation.

Based on this research, scientists found that ARX788 has the potential to benefit a broader spectrum of HER2+ cancer patients than those that can be treated with the currently available HER2 targeted therapies and to improve outcomes for those patients that are eligible for current HER2-targeted therapies.

Preclinical studies demonstrated that ARX788 is effective in controlling xenograft tumors, and safety studies in rodents and non-human primates demonstrated that ARX788 is well tolerated at doses significantly higher than the doses required to demonstrate efficacy.

Ambrx optimized ADCs are based on site-specific conjugation technology along with proprietary linkers and payloads.  The company owns the worldwide rights to ARX788, with the exception of the People’s Republic Of China, for which the rights to ARX788 have been licensed to Zhejiang Medicine Co., Ltd.


Editorial Review: March 4, 2015 | Last Update October 24, 2019