Bolt Biotherapeutics to Present Data from Phase 1 Dose-Escalation Clinical Study of BDC-3042 at AACR Annual Meeting 2025

Bolt Biotherapeutics (Nasdaq: BOLT), a clinical-stage biopharmaceutical company developing novel immunotherapies for the treatment of cancer, today announced it will present data from the Phase 1 dose-escalation clinical study of BDC-3042 in patients with advanced cancers at the American Association for Cancer Research (AACR) Annual Meeting, taking place April 25-30, 2025, in Chicago, Illinois.

BDC-3042 is a proprietary agonist antibody that targets dectin-2, an immune-activating receptor expressed by tumor-associated macrophages (TAMs). This single-agent, dose-escalation Phase 1 clinical study is evaluating BDC-3042 in patients with metastatic or unresectable solid tumors including non-small cell lung cancer (NSCLC).

Bolt will also be presenting preclinical data from two of its pipeline programs, Boltbody™ ISACs targeting CEA and PD-L1.

Details about the poster presentations can be found below and on the AACR website. Additionally, a copy of each poster will be available on the Publications page of the Bolt Biotherapeutics website at the start of each poster session.

Title: BDC-3042, a first-in-class Dectin-2 agonist, in patients with advanced malignancies: Results from the first-in-human dose-escalation study Presenter: Ecaterina E. Dumbrava, M.D., The University of Texas MD Anderson Cancer Center Poster Session: First-in-Human Phase I Clinical Trials 2 Session Date and Time: Tuesday, April 29, 2025, 9:00 a.m. – 12:00 p.m. CDT Location: Poster Section 48 Poster Number: 20 Abstract Number: CT154

Title: A highly efficacious next-generation CEACAM5 (CEA)-targeted Boltbody™ ISAC for the treatment of colorectal, pancreatic and lung tumors Presenter: Paul D. Ponath, Ph.D., Bolt Biotherapeutics Poster Session: T Cell Engagers and Novel Antibody-Based Therapies Session Date and Time: Wednesday, April 30, 2025, 9:00 a.m. – 12:00 p.m. CDT Location: Poster Section 40 Poster Number: 25 Abstract Number: 7399

Title: PD-L1-directed ISACs target host immune cells to drive powerful antitumor immune responses in a manner distinct from conventional PD-1/PD-L1 blockade Presenter: Justin A. Kenkel, Ph.D., Bolt Biotherapeutics Poster Session: T Cell Engagers and Novel Antibody-Based Therapies Session Date and Time: Wednesday, April 30, 2025, 9:00 a.m. – 12:00 p.m. CDT Location: Poster Section 40 Poster Number: 19 Abstract Number: 7333

About the Boltbody™ Immune-Stimulating Antibody Conjugate (ISAC) Platform Bolt Biotherapeutics’ Boltbody ISAC platform harnesses the precision of antibodies with the power of the innate and adaptive immune system to generate a productive anti-cancer response. Each Boltbody ISAC candidate comprises a tumor-targeting antibody, a non-cleavable linker, and a proprietary immune stimulant. The antibody is designed to target one or more markers on the surface of a tumor cell and the immune stimulant is designed to recruit and activate myeloid cells. Activated myeloid cells initiate a positive feedback loop by releasing cytokines and chemokines, chemical signals that attract other immune cells and lower the activation threshold for an immune response. This increases the population of activated immune system cells in the tumor microenvironment and promotes a robust immune response with the goal of generating durable therapeutic responses for patients with cancer.

About Bolt Biotherapeutics, Inc. Bolt Biotherapeutics is a clinical-stage biopharmaceutical company developing novel immunotherapies for the treatment of cancer. Bolt Biotherapeutics’ pipeline candidates are built on the Company’s deep expertise in myeloid biology and cancer drug development. The Company’s pipeline includes BDC-3042, a first-in-class agonist antibody that activates macrophages by targeting dectin-2, and BDC-4182, a next-generation Boltbody™ Immune-Stimulating Antibody Conjugate (ISAC) clinical candidate targeting claudin 18.2. BDC-3042 is currently in a Phase 1 dose escalation trial that includes patients with any of seven different solid tumor types. BDC-4182 is supported by strong in vitro and in vivo data demonstrating potent anti-tumor activity, and activities are underway to support the initiation of clinical trials in second quarter 2025. Bolt Biotherapeutics is also developing additional Boltbody™ ISACs in strategic collaborations with leading biopharmaceutical companies. For more information, please visit https://www.boltbio.com/.

Investor Relations and Media Contact: Matthew DeYoung Argot Partners (212) 600-1902 bolt[email protected]