Quantum Leap Healthcare Collaborative and Ambrx Biopharma have selected the latter’s antibody drug conjugate (ADC), ARX788, for a new investigational treatment arm in the Phase II I-SPY 2.2 TRIAL to treat HER2-positive breast cancer in the neoadjuvant setting. 

An anti-HER2 antibody drug conjugate (ADC), ARX788 is being analysed widely in breast cancer, gastric / gastroesophageal junction (GEJ) cancer and various other solid tumours. 

The adaptive trial is sponsored by Quantum Leap and assesses developing targeted agents to combine them with less toxic chemotherapeutic regimens or to completely replace cytotoxic chemotherapy. The company expects to commence subject enrolment in the ARX788 arms in May this year.

In the trial, ARX788 will be assessed as a single agent and along with the programmed cell death protein 1 (PD-1) targeting checkpoint inhibitor, cemiplimab, in subjects with HER2-positive early-stage breast cancer in the neoadjuvant setting. 

I-SPY 2.2 follows the I-SPY 2 TRIAL, designed to quickly analyse encouraging experimental therapies and detect the most effective ones in specific patient subgroups depending on molecular characteristics.

Ambrx Biopharma board chairman president and CEO Feng Tian said: “I am thrilled that Quantum Leap has selected Ambrx’s antibody drug conjugate, ARX788, to be evaluated in the I-SPY 2.2 TRIAL. 

“We are encouraged by the favourable anti-tumour activity and safety profile of ARX788 for the treatment of early-stage breast cancer. 

“It may provide a less toxic treatment option for patients through the precision conjugation of cytotoxic payloads targeting HER2 receptors.”

In April last year, Quantum Leap concluded subject enrolment in the icatibant arm of the I-SPY COVID Trial analysing various agents to treat critically ill patients.