The phase 1/2 study is for patients with advanced or metastatic solid tumours

Tallac Therapeutics has announced that the first patient has been treated with TAC-001 in a phase 1/2 clinical trial for patients with advanced or metastatic solid tumours.

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 Wan, chief executive officer at Tallac.

“As this study advances, we are also progressing additional assets in our pipeline and plan to file an investigational new drug application in the beginning of next year for our phase 1 study. This therapeutic candidate is a systemically delivered toll-like receptor 9 agonist targeting dendritic cells via SIRP-alpha receptors,” Wan added.

The phase 1/2 trial, known as INCLINE-101, is an open label, multicentre, dose escalation and expansion study of TAC-001 in patients with select advanced or metastatic solid tumours. It is designed to evaluate the safety, pharmacokinetics and preliminary anti-tumour 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-tumour immune responses, and in preclinical studies demonstrated potent single-agent activity,” said Candy Bermingham, vice president, clinical science at Tallac. “We look forward to better understanding the clinical utility of TAC-001 in advanced solid tumours 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 intratumourally. B cells express TLR9 and play a pivotal role in the immune system, and represent a major component of the tumour 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 tumour types.