WILMINGTON, Del. — The U.S. Food and Drug Administration has approved AstraZeneca’s immunotherapy drug IMFINZI (durvalumab) for use before and after surgery in patients with early-stage and locally advanced gastric and gastroesophageal junction cancers, making it the first immunotherapy cleared in the U.S. for this setting.
The decision allows IMFINZI to be used with FLOT chemotherapy prior to surgery, then again with chemotherapy after surgery, and finally as a standalone maintenance treatment. The approval applies to adults with Stage II, III, or IVA disease—patients historically at high risk of recurrence even after aggressive treatment.
The FDA’s ruling is based on results from the Phase III MATTERHORN trial, which found that adding IMFINZI to standard chemotherapy reduced the risk of disease progression, recurrence, or death by 29 percent compared with chemotherapy alone. Median event-free survival was not reached in the IMFINZI arm, while it was 32.8 months in the control arm.
Overall survival also improved. According to data presented at major oncology conferences this year, the IMFINZI regimen cut the risk of death by 22 percent. Three years after treatment, an estimated 69 percent of patients receiving the IMFINZI approach were still alive, compared with 62 percent of those treated with chemotherapy alone. The benefit appeared consistent across PD-L1 expression levels.
Gastric cancer remains one of the deadliest cancers worldwide, with about one million cases diagnosed each year. In the U.S., roughly 6,500 patients are treated annually for early-stage or locally advanced gastric or gastroesophageal junction cancers.
Oncologists involved in the study say the approval marks a notable shift. Yelena Janjigian, MD, of Memorial Sloan Kettering Cancer Center and the principal investigator for MATTERHORN, said the data “opens an entirely new chapter” in treating early-stage disease, noting that nearly seven in ten patients receiving the IMFINZI-based regimen were alive at three years.
Patient groups also welcomed the decision. Aki Smith, founder of Hope for Stomach Cancer, said many families face aggressive disease even when diagnosed early. “Today’s approval represents a major step forward in improving outcomes and offering renewed hope,” she said.
Safety results in the trial were in line with what is typically seen for IMFINZI and FLOT chemotherapy, and the percentage of patients able to undergo surgery was similar between groups.
The FDA reviewed the application through Project Orbis, a program that coordinates oncology drug reviews among multiple countries. Regulators in Australia, Canada, Switzerland, the European Union, Japan, and other regions are also evaluating the treatment.
