Pancreatic Cancer Eliminated in Mice with Triple Therapy, Spanish Scientists Report

The treatment was well tolerated by the animals, with no major toxicities reported.

Published: 1/30/2026, 11:18:37 PM EST

Pancreatic Cancer Eliminated in Mice with Triple Therapy, Spanish Scientists Report — White rats stand in a basin at an animal laboratory in a file photo. (China Photos/Getty Images)

Spanish researchers say they have found a powerful new combination treatment that completely eliminated pancreatic tumors in mice, a discovery that could point the way to better therapies for this type of cancer.

The findings were published in the Proceedings of the National Academy of Sciences (PNAS).

In laboratory experiments, scientists at the Spanish National Cancer Research Centre (CNIO) induced pancreatic cancer in mice by implanting tumor cells directly into the pancreas, a method designed to mimic how the disease develops in humans.

They then treated the animals with a “triple therapy” approach, using three different drugs simultaneously to block key biological functions that allow pancreatic tumors to grow and evade treatment.

The result was that the tumors disappeared completely, and in many cases remained gone for more than 200 days after treatment ended, with no signs of regrowth. This outcome was reported in both genetically engineered mice and in models where human pancreatic tumors were grafted into animals.

According to the American Cancer Society, pancreatic cancer accounts for roughly 3 percent of all cancers diagnosed in the United States but about 8 percent of all cancer deaths.

Symptoms often don’t appear until the disease is advanced, but may include abdominal pain that radiates to the back or sides, unintended weight loss, loss of appetite, and yellowing of the skin and eyes (also known as jaundice), the Mayo Clinic notes.

The American Cancer Society estimates that for pancreatic cancer in the United States, about 67,530 people will be diagnosed with pancreatic cancer, and bout 52,740 people will die of pancreatic cancer this year.

The new study’s triple therapy targeted three essential signaling pathways on which pancreatic tumors depend. These include: KRAS—a gene crucial for cell growth, which is mutated in most pancreatic cancers; EGFR—a receptor mediating growth signals; and STAT3—a protein that promotes cancer cell survival.

Blocking just one of these pathways alone usually leads tumors to adapt and survive by switching to alternative routes. However, by targeting several critical weaknesses simultaneously, researchers blocked the tumor’s ability to adapt.

The treatment was well tolerated by the animals, with no major toxicities reported. However, the work remains preclinical, as the results are from mouse models rather than human patients.

“This combination therapy also led to significant regression of genetically engineered mouse tumors as well as patient-derived tumor xenografts (PDX) in the absence of tumor relapses,” stated the study’s abstract. “Of importance, this combination therapy was well tolerated. In sum, these results should guide the development of new clinical trials that may benefit PDAC patients.”