Australian medical biotech company Imugene (ASX: IMU) has completed the recruitment of HER-2 gastric cancer patients for the Phase 1b clinical trial of its HER-Vaxx cancer vaccine.
The sequential dose escalation study – involving three groups of patients at trial sites in Asia and Eastern Europe where expensive antibody treatments can be difficult to access – is designed to evaluate the safety, tolerability, immunology and clinical activity of HER-Vaxx in combination with standard-of-care chemotherapy.
It will also establish the optimal dose for a larger Phase 2 study which will test the efficacy, safety and immune response of the selected dose in 68 gastric cancer patients with metastatic gastric cancer overexpressing the HER-2 protein.
Imugene managing director and chief executive officer Leslie Chong said clinicians at the trial sites have observed no toxicities and all vaccinated patients have developed immune responses and antibodies to the HER-2 protein, which encourages cancer growth.
“Completion of recruitment is an important milestone for this study and for the many medical professionals seeking treatments for patients with advanced gastric cancer who often have very few medical options,” she said.
“We look forward to reporting on further milestones and completing the analysis in the coming months.”
Ms Chong said the Phase 1b HER-Vaxx trial will recruit additional patients to the third cohort until the current evaluable patients have safely passed the dose limiting toxicity window.
In February, the company reported “promising results” from trials with the first cohort, which indicated the HER-Vaxx had demonstrated immune system activation in patients consistent with the vaccine’s anticipated action.
Phase 2 study preparations
In some cancerous cells, including those present in certain types of breast and gastric cancers, the HER-2 receptor is over-expressed, causing cancer cells to reproduce uncontrollably.
Imugene’s HER-Vaxx is designed to produce a strong antibody response against a cancer growth signal receptor protein called HER-2 which is found on the cell surface in breast and gastric cancers.
Preparation for Phase 2 has already commenced and a cohort review committee will determine the recommended dose for that study.
It will be randomised into two arms of either HER-Vaxx plus standard-of-care (chemotherapy) or standard-of-care alone.
Endpoints will be progression-free survival and overall survival.
Capital already raised
In June, Imugene reported a successful quarter with a $20.1 million capital raising from existing and new shareholders to support the acquisition of new B-cell peptide vaccine programs from Ohio State University and The Mayo Clinic.
Imugene believes the B-cell platform has the potential to be part of the “next wave of immuno-oncology products”, and brings treatment of multiple diseases via multi-level therapies within reach.
The acquisition has established a clinical presence for Imugene in the United States.
Funds from the capital raising will also be used to advance the company’s pipeline of clinical programs including those relating to HER2, PD-1 and combinations of the acquired B-cell vaccine.
At midday, shares in Imugene were trading 9.09% higher at $0.024.