Pancreatic cancer mRNA vaccine shows lasting immune response in small early trial

A personalized mRNA vaccine in a 16-person Phase 1 trial produced durable T cell responses, and six-year follow-up data show seven of eight vaccine responders were alive while two nonresponders were alive.

An early Phase 1 trial tested a personalized mRNA vaccine given after surgery for people with operable pancreatic cancer. The vaccine was made from genetic material taken from each patient’s tumor and given alongside standard post‑operative chemotherapy. Investigators tracked patients for six years to see whether immune responses persisted and whether those responses related to survival. The team plans to present the six‑year follow‑up findings at the American Association for Cancer Research meeting. Key findings: - The trial enrolled 16 patients and eight mounted measurable T cell responses to the personalized vaccine. - Six years after treatment, seven of the eight vaccine responders were alive; two of the eight patients who did not mount a response were alive. - Two responders experienced a cancer recurrence; one responder died. Donna Gustafson, the first participant treated, had no recurrence at the time of follow‑up. - Researchers report the vaccine appeared to prompt both killer (cytotoxic) T cells and helper T cells, which may support a durable immune response. - A larger Phase 2 trial is already underway to evaluate the vaccine in more patients. Summary: The six‑year follow up suggests that patients who generate a measurable immune response to the personalized mRNA vaccine lived longer in this small study. The finding is preliminary because of the small number of participants, and investigators have launched a larger Phase 2 trial to test the approach further.