Bolt Biotherapeutics, Inc. announced that it has entered into a clinical collaboration and supply agreement with Bristol Myers Squibb to investigate Bolt Biotherapeutics' BDC-1001 in combination with Bristol Myers Squibb's PD-1 checkpoint inhibitor Opdivo® (nivolumab). BDC-1001 is a HER2-targeting Boltbody™ immune-stimulating antibody conjugate (ISAC) in development for the treatment of patients with HER2-expressing solid tumors. BDC-1001 is a human epidermal growth factor receptor 2 (HER2) ISAC comprised of a HER2-targeting biosimilar of trastuzumab conjugated to one of Bolt's proprietary TLR7/8 agonists with an intervening non-cleavable linker, for the treatment of patients with HER2-expressing solid tumors.

It is currently being investigated in a Phase 1/2 clinical trial (NCT04278144) in patients with solid tumors, including breast, gastroesophageal and colorectal, that are HER2+ or HER2-low, for which Bolt recently presented preliminary data detailing safety, tolerability, and signs of activity at the 2021 American Society of Clinical Oncology (ASCO) Annual Meeting. The trial is being conducted in four parts, with dose-escalation and dose-expansion parts exploring both monotherapy and combination with a PD-1 checkpoint inhibitor. BMS will provide Opdivo for the combination dose escalation and combination dose expansion portions of the trial.

Bolt Biotherapeutics is the study sponsor and will be responsible for costs associated with the trial execution. The combination dose escalation is expected to start later in 2021.