US-based Triumvira Immunologics will aim for accelerated approval for its TAC01-HER2 by the US Food and Drug Administration (FDA) in gastric and oesophageal cancers, chief medical officer Dr Deyaa Adib told Clinical Trials Arena.
Adib noted: “It's an area of significant unmet medical needs, where the standard of care has not changed over the last 40 years."
TAC01-HER2 is a novel cell therapy that consists of genetically engineered autologous T cells expressing T-cell antigen coupler (TAC), which recognises human epidermal growth factor receptor 2 (HER2).
Triumvira Immunologics expects to complete the Phase II component of a Phase I/II trial in HER2-positive solid tumours in 2025. The Phase II portion will be a registration-enabling study and it is based on the three-stage Simon hypothesis. The second part of the trial is expected to enrol 72 patients who have passed between two to four prior lines.
Following the completion of all three stages, Triumvira will discuss with the FDA about the accelerated approval path based on the open-label, single-arm study (NCT04727151) whether TAC01-HER2 should be used as a monotherapy or in combination with an immune checkpoint inhibitor, said Adib.
Earlier this year, Triumvira announced a clinical collaboration and supply agreement with Merck (MSD) to evaluate TAC01-HER2 as a monotherapy and in combination with Keytruda (pembrolizumab).
After the accelerated approval, Triumvira will conduct a Phase III trial as a confirmatory study in patients in a second-line setting.
Phase I data
In May, Triumvira announced positive Phase I clinical data from the Phase I/II trial. The interim results showed that TAC01-HER2 had a highly favourable safety profile, with one dose-limiting toxicity of Grade 3 and one Grade 3 cytokine release syndrome observed at the highest dose.
The cell therapy demonstrated early signals of clinical activity, highlighting two partial responses in stage IVb gastric cancer patients and stage IV gastro-oesophageal junction (GOJ) patients.
The Phase I component of the study has enrolled 20 patients. It is a US-based trial with six sites open already, but the total number of sites will be ten, Adib said.
Further development plans
This year, Triumvira plans to enter its second programme and target Claudin 18.2-positive solid tumours. The company plans to welcome the first patient into the Phase I/II trial (NCT05862324) by the end of August.
The focus of the Phase I component of the study will be gastric, oesophageal, pancreatic, non-small cell lung cancer and ovarian cancers. Based on the results, Triumvira will define the population for the Phase II portion of the trial, which will also be a registration-enabling study.
Phase I will identify the maximum tolerated dose of TAC01-CLDN18.2 and define the dose-limiting toxicities. The primary endpoints in the Phase II trial will measure the overall response rate (ORR) and duration of response (DOR) while secondary endpoints will look at progression-free survival and safety.
