— TAC-001 is the First Candidate from Tallac’s Novel Toll-like Receptor Agonist Antibody Conjugate (TRAAC) Platform to Enter the Clinic

BURLINGAME, Calif. – (BUSINESS WIRE) – July 28, 2022 — Tallac Therapeutics, Inc., a privately held biopharmaceutical company harnessing the power of innate and adaptive immunity to fight cancer, today announced that the first patient has been dosed with TAC-001 in a Phase 1/2 clinical trial for patients with advanced or metastatic solid tumors. TAC-001 is the company’s lead clinical candidate from its novel Toll-like Receptor Agonist Antibody Conjugate (TRAAC) platform and the first to enter the clinic.

“The initiation of the first-in-human study for our lead therapeutic candidate represents a major milestone for Tallac as we work to advance our differentiated pipeline of immunotherapy candidates derived from our TRAAC platform,” said Hong I. Wan, Ph.D., president, CEO and co-founder of Tallac Therapeutics. “As this study advances, we are also progressing additional assets in our pipeline and plan to file an investigational new drug application (IND) in the beginning of next year for our Phase 1 study in partnership with ALX Oncology Holdings Inc. (Nasdaq: ALXO) for ALTA-002. This therapeutic candidate is a systemically delivered toll-like receptor 9 (TLR9) agonist targeting dendritic cells via SIRP-alpha receptors.”

The Phase 1/2 trial, known as INCLINE-101 (NCT05399654), is an open label, multicenter, dose escalation and expansion study of TAC-001 in patients with select advanced or metastatic solid tumors. It is designed to evaluate the safety, pharmacokinetics and preliminary anti-tumor activity of TAC-001 administered intravenously.

“TAC-001 is unique in that it integrates B cells and TLR9 activation to trigger innate and adaptive anti-tumor immune responses, and in preclinical studies demonstrated potent single-agent activity,” said Candy Bermingham, Ph.D., vice president, clinical science at Tallac Therapeutics. “We look forward to better understanding the clinical utility of TAC-001 in advanced solid tumors and the potential of this molecule to address the high unmet treatment needs that remain in multiple cancer types.”

Toll-like receptor 9 (TLR9) agonists are a class of immunotherapy that generate both innate and adaptive immune response, which may produce more robust and durable anti-cancer immunity to help overcome resistance to standard-of-care oncology treatments. TLR9 agonists have demonstrated clinical activity in melanoma patients when administered intratumorally. B cells express TLR9 and play pivotal roles in the immune system, and represent a major component of the tumor microenvironment, where they are predominantly associated with tertiary lymphoid structure (TLS). The presence of B cells and TLS is a positive prognostic factor and predicts treatment response to checkpoint inhibitors in multiple solid tumor types.

Tallac Therapeutic’s TRAAC platform is designed to deliver a potent and differentiated TLR9 agonist (T-CpG) for targeted immune activation via systemic administration. TAC-001 is an antibody-oligonucleotide conjugate, comprised of T-CpG conjugated to an antibody against CD22, a receptor restricted to B cells, including tumor-infiltrating B cells. Preclinical studies demonstrate that the innate and adaptive immune responses triggered by TAC-001 leads to robust, curative, and durable single agent anti-tumor activity in checkpoint inhibitor resistant and refractory tumor models. Increased B cell infiltration, T cell effector functions and modulation of suppressive myeloid cells within the tumor microenvironment were observed following systemic TAC-001 administration. These results support the development of TAC-001 for a broad range of solid tumor malignancies, particularly in the tumor types with B cell/TLS involvement.

About TAC-001
TAC-001 is a Toll-like Receptor Agonist Antibody Conjugate (TRAAC) comprised of a potent toll-like receptor 9 agonist (T-CpG) conjugated to an antibody against CD22, a receptor restricted to B cells, including tumor-infiltrating B cells. TAC-001 is designed to systemically deliver T-CpG to B cells by binding to CD22, leading to internalization of TAC-001, TLR9 signaling, B cell activation and a cascade of immune reactions. Preclinical studies demonstrate that the innate and adaptive immune responses triggered by TAC-001 leads to potent anti-tumor activity. TAC-001 is being developed for the potential treatment of solid tumors.

About Tallac Therapeutics, Inc.
Tallac Therapeutics is a privately held biopharmaceutical company harnessing the power of innate and adaptive immunity to fight cancer. Tallac’s pipeline of immunotherapy candidates are derived from the company’s novel Toll-like Receptor Agonist Antibody Conjugate (TRAAC) platform to deliver a potent Toll-like receptor (TLR9) agonist (T-CpG) for targeted immune activation via systemic administration. Several TRAAC molecules are in various stages of discovery and preclinical development. For more information, please visit www.tallactherapeutics.com.

Tallac Media Contact:
Tara Cooper
The Grace Communication Group
(650) 303-7306
tara@gracegroup.us