Imugene's promising trial results: five patients with >30% decrease in tumour size
Clinical stage immuno-oncology company, Imugene (ASX:IMU), has met all study endpoints and produced positive top-line results from its Phase 1b study of its HER-Vaxx gastric cancer vaccine.
14 patients, who all express the HER2 target protein, were tested three across three dose levels of HER-Vaxx (10, 30 and 50 micrograms) in combination with current standard of care chemotherapy, cisplatin and fluorouracil or capecitabine.
The response rate is considered an exploratory endpoint in the Phase 1b study, with results showing that of the 10 patients evaluable for tumour growth assessment during the study, five patients showed partial response (PR) and four patients showed stable disease (SD) for their best overall response.
Promisingly, all dose levels showed an increased antibody response in patients, no safety issues were reported, and HER-Vaxx was found to be well-tolerated.
As a result of the study, the Cohort Review Committee recommended a dose of 50 micrograms for the Phase 2 dose, based on the safety and immunogenicity data.
“We would like to sincerely thank the medical researchers and patients who participated in this study,” IMU managing director and CEO, Leslie Chong, said of the news.
“Together, we are cautiously encouraged by meeting all the endpoints of the study and data from the top-line results in a small sample size, in particular the five patients whose best response showed more than 30% decrease in their tumour size from baseline scans.”
“With these early results from the HER-Vaxx clinical study, Imugene’s B-cell active immunotherapy approach is showing positive signs, which provides us with further confidence in our B-cell immunotherapy pipeline.
“This is a promising milestone for Imugene and the many medical professionals seeking treatments for patients with advanced gastric cancer who often have very few medical options,” she said.
Phase 2 trial: first patient to be dosed in early 2019
The Phase 2 study will test the efficacy, safety and immune response to HER-Vaxx in 68 gastric cancer patients with metastatic gastric cancer over-expressing the HER-2 protein.
It will be randomised into two arms of either HER-Vaxx plus standard-of-care chemotherapy or standard-of-care alone. The primary endpoint will be overall survival and the secondary endpoint will be progression-free survival.
The study will be conducted at sites across Asia, Eastern Europe and India where treatments such as Herceptin and Perjeta are not readily available to patients. There is also a high prevalence of gastric cancer in many of the countries selected.
HER-Vaxx is designed to produce an antibody response against a cancer growth signal receptor protein called HER-2 which is found on the cell surface in breast and gastric cancers.