In February, Timothée Olivier, MD, wrote that PATINA’s progression-free survival gain “may have been artifically inflated.” In June, the FDA approved palbociclib maintenance on that endpoint. In October, the EMA said the benefit “had not been demonstrated.”
PATINA (AFT-38) added palbociclib (IBRANCE) to anti-HER2 maintenance and endocrine therapy after induction in HR-positive, HER2-positive metastatic breast cancer. The trial was open-label. The primary endpoint was investigator-assessed progression-free survival (PFS).
On February 8 he published the full analysis on The Oncology Shot. He noted that the NEJM publication did not report the number of censored patients, and estimated it from the Kaplan-Meier curves:
“5.3% of patients censored over the first 6 months in the palbociclib group and 12.1% of them in the control group.”Timothée Olivier, MD, The Oncology Shot, February 8, 2026
His conclusion:
“In conclusion, given the possible biases introduced by informative censoring, an open-label design, and the lack of BICR, the PFS gain as reported may have been artifically inflated.”Timothée Olivier, MD, The Oncology Shot, February 8, 2026
NEJM published two letters to the editor on PATINA and a reply from the lead author, Otto Metzger, MD. The opening of the first letter, visible on NEJM’s site, questions the design: patients were randomized only after they had no progression on four to eight cycles of chemotherapy plus HER2-targeted therapy, which the letter says “shifts the clinical time zero and enriches the trial for favorable biologic features.” The rest of the correspondence and the reply are behind NEJM’s paywall.
Pfizer’s withdrawal letter is dated September 15, 2026. The EMA made the withdrawal public on October 16, 2026, in the highlights of the CHMP’s October 12–15 meeting and in a question-and-answer document that gives the Agency’s reasons. The October 16 publication is the first public record we found. Coverage followed from October 19, and physician reaction on X peaked on October 21.
“The Agency considered that the study did not provide sufficiently reliable evidence that Ibrance was effective in the proposed use. The study was open-label, meaning that the patients and the doctors carrying out the study knew which treatment was being given. The main assessment of whether the cancer had worsened was made by these doctors, and differences between their assessments and an independent review of the scans raised concerns that the results may have been biased in favour of Ibrance. The independent review did not confirm a clear improvement, and the other measures of effectiveness did not provide sufficient supporting evidence.”
“Therefore, at the time of the withdrawal, the Agency’s opinion was that the benefits of Ibrance in the maintenance treatment of HR-positive, HER2-positive locally advanced or metastatic breast cancer had not been demonstrated.”
European Medicines Agency, Questions and answers on the withdrawal, October 16, 2026The same document: “There are no consequences for Ibrance in its authorised uses.”
| Olivier, February 8, 2026 | EMA, October 16, 2026 | |
|---|---|---|
| Design | “an open-label design” | “The study was open-label” |
| Who called progression | “The primary end point was investigator-assessed progression-free survival (PFS).” | “The main assessment of whether the cancer had worsened was made by these doctors” |
| Direction of bias | “In an open-label setting, investigators may be more inclined to declare progression earlier in control patients when scans are borderline or tumor growth is still below formal RECIST thresholds, because there’s a practical incentive to move quickly to the next line of therapy or another trial.” | “the results may have been biased in favour of Ibrance” |
| Bottom line | “the PFS gain as reported may have been artifically inflated” | “the benefits of Ibrance … had not been demonstrated” |
Olivier’s February piece cited a lack of blinded independent central review. The EMA’s Q&A refers to an independent review of the scans. The NEJM paper and the FDA label report investigator-assessed PFS.
More physician discussion of PATINA, including the EMA and Japan reactions and the sequencing debate after DESTINY-Breast09, is on the PATINA trial profile.
Not surprised: My take on PATINA:Timothée Olivier, MD (@Timothee_MD), October 21, 2026, linking his February analysis
🚨 PATINA: The EMA questions a 15-month PFS gain (HR 0.75). I highly recommend 📖https://t.co/pIPlN34KPj by @Timothee_MD: An open-label trial, investigator-assessed PFS, and estimated early censoring of 12.1% in controls vs 5.3% with palbociclib. Robust benefit or potential assessment bias?Pablo Jara Martín (@pablojaramartin), October 21, 2026
Hoping we will get more clarity into this decision. https://t.co/c5y3gCQgy3Neil Vasan (@NeilVasan), October 21, 2026
Full physician reactions, the sentiment table, the FDA label data and the complete EMA and Pfizer statements are on the PATINA trial profile.
Sources: Timothée Olivier, “The PATINA trial – palbociclib maintenance in metastatic breast cancer,” The Oncology Shot, February 8, 2026 · Metzger et al., N Engl J Med 2026;394:451-462, January 29, 2026 · Correspondence, N Engl J Med 2026;394:1764-1766, April 30, 2026 · FDA approval notice, June 24, 2026 · IBRANCE prescribing information, June 2026 · CHMP draft agenda, September 14–17, 2026 · Pfizer withdrawal letter, September 15, 2026 · Pfizer Japan press release, September 16, 2026 · EMA questions and answers, October 16, 2026. Physician posts quoted verbatim from X.
Brian Shields, Founder, KOL Pulse. October 22, 2026.