A patient treated with a single dose of AdAlta’s experimental CAR T cell therapy EW 001 has remained free of cancer recurrence for two years, marking a significant milestone in the company’s ongoing mesothelioma study in China.
The patient was the first participant in the investigator-initiated trial to achieve a Complete Response, meaning that no tumour could be detected following treatment.
A second patient who also achieved a Complete Response has now survived for more than 12 months after receiving EW 001. No imaging assessment was conducted at the one-year milestone, so the second patient’s current tumour status is not available.
AdAlta said EW 001 has produced Complete Responses in two of the ten patients treated at higher doses, representing a response rate of 20 per cent. Across all 14 evaluable patients treated with the current generation of the therapy, the Complete Response rate stands at 14 per cent.
The results are notable because complete tumour clearance is rarely seen in patients with advanced mesothelioma. The disease affects the membranes surrounding organs, including the lungs, heart, and gastrointestinal tract, and is commonly associated with asbestos exposure. Although patients are typically treated initially with chemotherapy or immunotherapy, treatment options become increasingly limited when the disease returns or progresses.
Published studies of second-line and later treatments for advanced mesothelioma have generally reported Complete Response rates of zero per cent, according to AdAlta. The company said this makes the durability of the first patient’s response particularly significant.
“Complete tumour clearance is almost never seen in patients with advanced mesothelioma. To have achieved it in two (20%) of the ten patients treated at the higher EW-001 doses is highly encouraging – and to see the first of those patients still free of cancer recurrence two years after a single infusion is the kind of result that changes the conversation with patients, regulators and partners.”
AdAlta said it will continue monitoring the patients involved in the study and plans to report further survival and response data as it becomes available.
The company is also preparing for the next stage of EW 001’s development. It is transferring the therapy’s manufacturing process to Cell Therapies, with the first Australian manufacturing runs expected in the second half of 2026. AdAlta is also preparing for a pre-Investigational New Drug meeting with the United States Food and Drug Administration during the same period.
The company said these steps are intended to establish an Australian manufacturing platform, obtain regulatory guidance and support a planned Australian Phase 1 clinical study.
EW 001, formerly known as BZDS1901, is a CAR T cell therapy designed to use a patient’s own engineered immune cells to identify and destroy cancer. AdAlta is developing the treatment for mesothelioma and is also exploring its potential application in more than ten other cancers.
