A cancer that has resisted meaningful treatment for more than half a century may finally have a credible scientific path forward.
In late 2025, researchers at Spain’s National Cancer Research Centre (CNIO), led by Dr. Mariano Barbacid, published findings in PNAS describing a triple drug combination that eliminated pancreatic tumors completely in mouse models without triggering drug resistance, a result that drew immediate international attention.
Then the study was retracted.
That retraction is not the end of the story.
It is actually the beginning of a far more important one.
The paper was pulled from PNAS in April 2026, not because the science was wrong, but because Barbacid and two co-authors failed to disclose a financial interest in a company tied to the research.
According to the formal retraction notice in PNAS, the issue was procedural: the submission used a track reserved for members without competing interests, when financial ties to a company called Vega Oncotargets should have been declared and triggered a different review process.
The research team has described this as an administrative matter and has resubmitted the study through the standard peer-review process with full disclosure.
Meanwhile, one of the three drugs at the heart of that triple therapy approach, daraxonrasib, has just produced the most significant result in pancreatic cancer research in decades.
A Phase 3 clinical trial, published simultaneously in the New England Journal of Medicine and presented at the 2026 ASCO Annual Meeting, showed that daraxonrasib nearly doubled median survival for patients with previously treated metastatic pancreatic cancer, from 6.7 months on standard chemotherapy to 13.2 months.
The announcement received a standing ovation from oncologists at ASCO.
For a disease where fewer than 13% of patients survive five years after diagnosis, that is not a minor improvement.
That is a paradigm shift.
Why Pancreatic Cancer Has Been So Hard to Treat
Pancreatic ductal adenocarcinoma (PDAC) is the most common and deadliest form of pancreatic cancer.
It is also one of the cruelest cancers in medicine.
It rarely causes noticeable symptoms in its early stages, which means most patients receive a diagnosis only after the disease has already spread.
According to the National Cancer Institute, approximately 97% of patients diagnosed with metastatic pancreatic cancer between 2015 and 2021 died within five years.
There are no reliable screening tools for the general population.
Standard chemotherapy regimens have improved somewhat over the decades, but they have never produced a meaningful survival advantage in patients with advanced disease.
For more than 50 years, that was the ceiling.
The reason pancreatic cancer resists treatment so tenaciously comes down largely to a single gene: KRAS.
KRAS is mutated in approximately 90% of all pancreatic cancer cases.
It acts as a molecular on-switch for cancer cell growth, and historically it was considered essentially impossible to target with drugs.
Scientists spent decades calling it “undruggable.”
The first drugs designed specifically to block KRAS were only approved in 2021, representing the first major mechanistic advance over conventional chemotherapy in more than half a century.
Those drugs were a genuine step forward.
But they came with a deeply frustrating limitation: tumors quickly adapted and became resistant, often within months.
The KRAS Resistance Problem and the Triple Threat Idea
This is the problem that Barbacid’s team at CNIO set out to solve.
Their insight was conceptually elegant.
When a single drug blocks one point in the KRAS signaling pathway, cancer cells find other routes through the network to keep growing.
Biological systems are redundant by design.
Blocking one exit does not close the maze.
As Technology Networks explained in its coverage of the research, the Barbacid team’s strategy was to attack the KRAS pathway at three independent points simultaneously: blocking downstream signaling through RAF1, upstream signaling through EGFR, and a completely separate survival route through STAT3.
Think of it as blocking three different escape roads at the same time.
When all three are closed, the cancer cell has nowhere to go.
The drugs chosen to execute this strategy were daraxonrasib (a KRAS inhibitor), afatinib (an approved drug already used for certain lung cancers that blocks the EGFR receptor), and SD36 (a protein degrader that eliminates the STAT3 protein entirely).
In three separate mouse models of pancreatic ductal adenocarcinoma, this combination produced complete tumor regression that lasted more than 200 days after treatment ended, with no evidence of resistance and no significant toxicity to healthy tissue.
As News-Medical reported in its coverage of the findings, the therapeutic impact extended beyond mouse tumor cells to human tumor-derived patient models as well, which made the result even more promising.
No result like this had ever been produced in these models before.
The Retraction and What It Actually Means
Before going further, this story requires honesty about what happened after the PNAS paper was published.
On April 27, 2026, PNAS formally retracted the study.
The reason was not scientific misconduct or falsified data.
According to the retraction notice and multiple independent analyses, the editorial process used was inappropriate because three of the authors held financial stakes in Vega Oncotargets, a biotechnology company created specifically to commercialize the triple therapy.
PNAS policy requires that authors with such interests submit through a different, more rigorous track.
The authors did not do this.
The journal chose retraction over a correction, which is the strictest possible response, and one that reflects how seriously publishers take conflict of interest disclosure, regardless of whether the underlying science is sound.
Barbacid’s position is that the laboratory results are valid and that the issue is purely administrative.
The team has resubmitted the paper with full disclosure of competing interests and awaits independent peer review.
Crucially, the scientific validity of the experiments has not been challenged.
The data from the mouse models stands.
The mechanistic rationale for the triple therapy approach stands.
And as the clinical results for daraxonrasib have now demonstrated at the highest level of medical evidence, the underlying direction of this research was pointing somewhere real.
Here Is Where the Conventional Thinking About “Failed” Studies Falls Apart
Most people, when they hear that a study has been retracted, assume the science is dead.
A retraction sounds final.
It sounds like a verdict on the research itself.
The reality of scientific publishing is considerably more complicated, and this case illustrates why.
Retractions happen for a range of reasons: falsified data, honest statistical errors, unreproducible results, plagiarism, and yes, undisclosed conflicts of interest.
Only the first of those categories means the science itself was invented.
In this case, the CNIO laboratory work was conducted, peer-reviewed by three named reviewers including David A. Tuveson, one of the world’s leading pancreatic cancer researchers, and found to be scientifically sound.
The problem was the disclosure process, not the pipettes.
And now consider what has happened in the months since the retraction.
Daraxonrasib, the KRAS inhibitor at the center of Barbacid’s triple therapy approach, has just completed one of the most consequential clinical trials in oncology this decade.
The Phase 3 RASolute 302 trial, published in the New England Journal of Medicine, enrolled 500 patients with previously treated metastatic pancreatic cancer and compared daraxonrasib against standard-of-care chemotherapy.
The drug reduced the risk of death by 60% compared to chemotherapy, with a hazard ratio of 0.40.
Median survival nearly doubled.
Approximately 90% of patients experienced disease control, meaning their cancer was reduced or stabilized.
The drug was well tolerated.
As Dana-Farber Cancer Institute reported on the trial results, this represents the first substantial survival advantage over chemotherapy ever demonstrated in a large randomized trial for this patient population.
The science behind the KRAS inhibitor approach, the same science underpinning the CNIO triple therapy research, just produced the biggest advance in pancreatic cancer treatment in the modern era.
Why the Triple Therapy Approach Still Matters
Daraxonrasib as a single agent is remarkable.
But the CNIO research, and the broader scientific context around it, suggests that even this achievement may only be the beginning.
The resistance problem that Barbacid’s team was trying to solve with the triple therapy approach does not disappear simply because daraxonrasib works better than chemotherapy.
As the ESMO Daily Reporter noted in its analysis of the KRAS inhibition landscape, RAS(ON) inhibitors like daraxonrasib represent a major advance, but the rapid onset of tumor resistance has historically frustrated their long-term therapeutic benefit in other settings.
The triple therapy concept, blocking KRAS at three independent nodes simultaneously, was designed specifically to prevent that resistance from ever getting started.
If daraxonrasib continues to show the kind of activity seen in the Phase 3 trial, the next logical clinical question is whether combining it with afatinib and a STAT3 inhibitor could extend those gains further, producing responses that last not months but years.
Revolution Medicines, the developer of daraxonrasib, has already initiated three additional Phase 3 trials, including one testing daraxonrasib in combination with chemotherapy as a first-line treatment for patients who have not yet received any therapy.
The pathway from single drug to triple combination therapy is not hypothetical.
It is already being built.
What the KRAS Science Means Beyond Pancreatic Cancer
One of the most significant aspects of this entire field of research is how broadly it may apply.
KRAS mutations are not unique to pancreatic cancer.
They are among the most common cancer-driving mutations in human biology, found in approximately 25% of all human cancers, including lung adenocarcinoma and colorectal cancer.
As Memorial Sloan Kettering Cancer Center has reported on the daraxonrasib trials, the drug received FDA Breakthrough Therapy designation in June 2025 and the FDA has since issued a “safe to proceed” letter allowing expanded access for patients who cannot participate in clinical trials.
OncLive reporting on the expanded access program confirmed that the program opened in May 2026, allowing patients with RAS-mutated pancreatic cancer outside of clinical trials to begin accessing the drug now.
That is a meaningful development for patients today, not just patients in the future.
What Patients and Families Should Know Right Now
If you or someone you love is dealing with a pancreatic cancer diagnosis, the landscape in 2026 is genuinely different from what it was even two years ago.
Daraxonrasib is available through an expanded access program for patients with previously treated RAS-mutated metastatic pancreatic cancer who do not qualify for clinical trials.
Phase 3 trials comparing daraxonrasib to chemotherapy as a first-line treatment are actively enrolling.
The fact that approximately 90% of pancreatic cancer cases carry KRAS mutations means that the vast majority of patients are biologically eligible for this class of drugs.
ScienceDaily’s coverage of the RASolute 302 results described daraxonrasib as the first drug to crack what had been considered an undruggable target in a way that produced a clinically meaningful survival advantage in a large randomized trial.
Those are not routine words in cancer medicine.
They reflect a genuine shift in what is possible.
The Bigger Picture on Drug Resistance
The problem that originally motivated the CNIO triple therapy research remains one of the most important open questions in oncology.
Even with daraxonrasib showing unprecedented efficacy, the history of KRAS inhibitors in other cancers suggests that resistance will eventually develop in some patients, as it does with most targeted therapies.
A May 2026 Nature commentary described the success against KRAS as raising new hopes not just for pancreatic cancer but for the entire class of “undruggable” oncogenes that have resisted therapeutic targeting for decades.
The authors also noted that the next frontier, much as Barbacid’s work anticipated, will involve combination strategies designed to block the cancer’s escape routes before it can use them.
The CNIO research, even while awaiting re-publication in a peer-reviewed journal, contributed to the scientific conversation that is now accelerating at a remarkable pace.
That is how science actually works: imperfectly, iteratively, sometimes controversially, and with setbacks that do not always mean what they appear to mean at first glance.
A retracted paper is not a buried idea.
An undisclosed conflict of interest is a serious procedural failure, but the biology does not care about the paperwork.
A Disease That Is Finally Being Understood
Pancreatic cancer has spent decades being called untreatable, and statistically, that was close to true.
The discoveries arriving now, from Barbacid’s triple pathway concept to daraxonrasib’s landmark Phase 3 results, represent the most concentrated period of genuine scientific progress this disease has seen since the field began taking KRAS seriously as a drug target.
The researchers who have spent careers working on this problem, including the scientists at CNIO who are now resubmitting their work through proper channels, are part of a broader wave of progress that was never going to be stopped by a procedural issue in a journal.
For the families who have lost someone to this disease, and for the patients receiving diagnoses today, the fact that there is now a drug that can nearly double survival time in metastatic pancreatic cancer is not an abstraction.
For the first time in a very long time, the science is moving faster than the disease.
Know someone affected by pancreatic cancer, or working in oncology? Share this piece. The most important treatment developments in this field are happening right now.
