PALbociclib CoLlaborative Adjuvant Study

• Palbociclib (Drug)
• Standard Adjuvant Endocrine Therapy (Drug)

Primary outcomes

• Invasive Disease Free Survival (iDFS) [4 years]: Invasive disease-free survival (iDFS) for the combination of at least 5 years endocrine therapy and 2-year palbociclib treatment versus at least 5 years endocrine therapy alone in patients with histologically confirmed HR+/HER2- invasive early breast cancer (EBC) at 4 years. iDFS is defined as the time from randomization to the date of the first event: local/regional invasive ipsilateral recurrence, contralateral invasive breast cancer, distant recurrence, second primary invasive cancer of non-breast origin or death from any cause. Direct comparison between arms used time to iDFS events and Kaplan-Meier Log-rank analysis. Due to the medians not yet achieved, the percentage of patients considered iDFS at 4 years is reported.

Secondary outcomes

• Invasive Disease Free Survival (iDFS) Excluding Second Primary Invasive Cancers of Non-breast Origin. [4 years]: Invasive disease-free survival (iDFS, excluding second primary invasive cancers of non-breast origin) for the combination of at least 5 years endocrine therapy and 2-year palbociclib treatment versus at least 5 years endocrine therapy alone in patients with histologically confirmed HR+/HER2- invasive early breast cancer (EBC) at 4 years. iDFS excluding second primary invasive cancers of non-breast origin is defined as the time from randomization to the date of the first event: local/regional invasive ipsilateral recurrence, contralateral invasive breast cancer, distant recurrence, or death from any cause. Second primary invasive cancers of non-breast origin will not be considered as events for this endpoint. Direct comparison between arms used time to iDFS events and Kaplan-Meier Log-rank analysis. Due to the medians not yet achieved, the percentage of patients considered iDFS at 4 years is reported.
• Distant Recurrence-free Survival (DRFS) [4 years]: Compare time to distant recurrence-free survival (DRFS). Distant recurrence is defined according to STEEP criteria as the time from randomization to the date of the first event: distant recurrence or death from any cause. Patients with a locoregional recurrence will continue to be followed for DRFS. Surviving patients who are event-free will be censored at: the date of last disease assessment, or withdrawal of consent to be followed, or death whichever came first. Direct comparison between arms used time to DRFS events and Kaplan-Meier Log-rank analysis. Due to the medians not yet achieved, the percentage of patients considered DRFS at 4 years is reported.
• Overall Survival (OS) [4 years]: Compare overall survival (OS). Overall survival is defined as the time period between randomization and death. Surviving patients classified as lost-to-follow up or having withdrawn consent to be followed will be censored at their date of last contact or withdrawal of consent to be followed, whichever occurs first.
• Locoregional Recurrences-free Survival (LRRFS) [4 years]: Compare locoregional recurrence-free survival (LRRFS). LRRFS is defined as the time from randomization to the date of the first event: local/regional invasive ipsilateral recurrence, contralateral invasive breast cancer, or death from any cause. Patients with second primary invasive cancers of non-breast origin or distant recurrence will be censored at the date of diagnosis. Surviving patients who are event-free will be censored at: the date of last disease assessment, or withdrawal of consent to be followed, whichever occurs first.

Sex: All, ages: 18 Years to any

Inclusion Criteria:

* Signed informed consent prior to study specific procedures.
* Age ≥18 years (or per national guidelines).
* Pre- and postmenopausal women or men with Stage II (Stage IIA limited to max. 1000 patients) or Stage III early invasive breast cancer
* Patients with multicentric and/or multifocal and/or bilateral early invasive breast cancer are eligible if all histopathologically examined tumors meet pathologic criteria for ER+ and/or PR+ and HER2-.
* Patients must have histologically confirmed ER+ and/or PR+, HER2-, early invasive breast cancer.
* Patients must have undergone adequate (definitive) breast surgery for the current malignancy.

FFPE tumor tissue block must be confirmed to be received at the central sample repository prior to randomization.

* ECOG performance status 0-1.
* Patients must be able and willing to swallow and retain oral medication.
* Serum or urine pregnancy test must be negative in premenopausal women within 14 days of randomization, or in women with amenorrhea of less than 12 months at time of randomization.
* Patients who received neo/adjuvant therapy must be after last dose of chemotherapy and/or biologic therapy and must have sufficient resolution of side effects.
* Patients who received breast/axilla/post-mastectomy chest wall radiotherapy must be after last dose of radiotherapy and must have sufficient resolution of side effects.
* Patients must have sufficient resolution of any surgical side effects (no active wound healing complications).

-Patients must either be initiating or have already started adjuvant hormonal treatment. -

* Patients who already received neo/adjuvant endocrine therapy are eligible as long as they are enrolled within 12 months of initial histological diagnosis and after completing no more than 6 months of adjuvant endocrine therapy.
* Absolute neutrophil count ≥ 1,500/µL
* Platelets ≥ 100,000/ mm3
* Hemoglobin ≥ 10g/dL
* Total serum bilirubin ≤ ULN; or total bilirubin ≤ 3.0 × ULN with direct bilirubin within normal range in patients with documented Gilbert's Syndrome.
* Aspartate amino transferase (AST or SGOT) and alanine amino transferase (ALT or SGPT) ≤ 1.5 × institutional ULN.
* Serum creatinine below the upper limit of the institutional normal range (ULN) or creatinine clearance ≥ 60 mL/min/1.73 m2 for patients with serum creatinine levels above institutional ULN.

Exclusion Criteria:

* Concurrent therapy with other Investigational Products.
* Prior therapy with any CDK inhibitor.
* Patients with Stage I or IV breast cancer are not eligible.
* History of allergic reactions attributed to compounds of chemical or biologic composition similar to palbociclib.
* Patients receiving any medications or substances that are potent inhibitors or inducers of
* CYP3A isoenzymes within 7 days of randomization.
* Uncontrolled intercurrent illness that would limit compliance with study requirements.
* Pregnant women, or women of childbearing potential without a negative pregnancy test within 14 days prior to randomization.
* Patients with a history of any malignancy are ineligible
* Patients who previously received endocrine therapy within 5 years prior to diagnosis of the current malignancy.
* Patients on antiretroviral therapy.
* Patients with clinically significant history of any chronic liver disease.
* Patients receiving concurrent exogenous hormone therapy (topical vaginal estrogen therapy is allowable).

337 more sites not listed.

• Results publication: Shinn E, Zahrieh D, DeMichele A, Zdenkowski N, Lemieux J, Mao J, Bjelic-Radisic V, Naughton MJ, Pfeiler G, Gelmon K, Balko JM, Egle D, Zoppoli G, Traina T, Jimenez MM, Novoa SA, Haddad T, Chan A, Ring A, Wolff A, Symmans WF, Ponce Lorenzo J, Sabanathan D, Burstein HJ, Nowecki ZI, Pristauz-Telsnigg G, Brufsky A, Bellet-Ezquerra M, Foukakis T, Novik Y, Rubovszky G, Singer CF, Muehlbacher K, Filho OM, Goulioti T, Law E, Partridge AH, Carey LA, Zoroufy A, Hlauschek D, Fesl C, Mayer EL, Gnant M. Impact of adding palbociclib on treatment adherence to ongoing adjuvant endocrine treatment in the global randomized PALLAS randomized trial in patients with early breast cancer. Breast Cancer Res Treat. 2025 Jun;211(2):385-397. doi: 10.1007/s10549-025-07653-2. Epub 2025 Mar 27. PMID 40140172
• Results publication: DeMichele A, Dueck AC, Hlauschek D, Martin M, Burstein H, Pfeiler G, Zdenkowski N, Wolff A, Bellet-Ezquerra M, Winer E, Balic M, Miller K, Colleoni M, Lake D, Rubovsky G, Cameron D, Balko J, Singer CF, Nowecki Z, Iwata H, Wolmark N, Parraga KA, Rugo H, Steger GG, Traina T, Werutsky G, Czajkowska D, Metzger O, El-Abed S, Theall KP, Lu RD, O'Brien P, Fesl C, Mayer E, Gnant M. Outcomes in stage IIA versus stage IIB/III in the PALLAS trial [ABCSG-42/AFT-05/PrE0109/BIG-14-13]). Breast Cancer Res. 2025 Jan 23;27(1):12. doi: 10.1186/s13058-024-01941-3. PMID 39849600
• Results publication: Pfeiler G, Hlauschek D, Mayer EL, Deutschmann C, Kacerovsky-Strobl S, Martin M, Meisel JL, Zdenkowski N, Loibl S, Balic M, Park H, Prat A, Isaacs C, Bajetta E, Balko JM, Bellet-Ezquerra M, Bliss J, Burstein H, Cardoso F, Fohler H, Foukakis T, Gelmon KA, Goetz M, Haddad TC, Iwata H, Jassem J, Lee SC, Linderholm B, Los M, Mamounas EP, Miller KD, Morris PG, Munzone E, Gal-Yam EN, Ring A, Shepherd L, Singer C, Thomssen C, Tseng LM, Valagussa P, Winer EP, Wolff AC, Zoppoli G, Machacek-Link J, Schurmans C, Huang X, Gauthier E, Fesl C, Dueck AC, DeMichele A, Gnant M; PALLAS Groups and Investigators. Impact of BMI in Patients With Early Hormone Receptor-Positive Breast Cancer Receiving Endocrine Therapy With or Without Palbociclib in the PALLAS Trial. J Clin Oncol. 2023 Nov 20;41(33):5118-5130. doi: 10.1200/JCO.23.00126. Epub 2023 Aug 9. PMID 37556775
• Results publication: Mayer EL, Fesl C, Hlauschek D, Garcia-Estevez L, Burstein HJ, Zdenkowski N, Wette V, Miller KD, Balic M, Mayer IA, Cameron D, Winer EP, Ponce Lorenzo JJ, Lake D, Pristauz-Telsnigg G, Haddad TC, Shepherd L, Iwata H, Goetz M, Cardoso F, Traina TA, Sabanathan D, Breitenstein U, Ackerl K, Metzger Filho O, Zehetner K, Solomon K, El-Abed S, Theall KP, Lu DR, Dueck A, Gnant M, DeMichele A. Treatment Exposure and Discontinuation in the PALbociclib CoLlaborative Adjuvant Study of Palbociclib With Adjuvant Endocrine Therapy for Hormone Receptor-Positive/Human Epidermal Growth Factor Receptor 2-Negative Early Breast Cancer (PALLAS/AFT-05/ABCSG-42/BIG-14-03). J Clin Oncol. 2022 Feb 10;40(5):449-458. doi: 10.1200/JCO.21.01918. Epub 2022 Jan 7. PMID 34995105
• Results publication: Gnant M, Dueck AC, Frantal S, Martin M, Burstein HJ, Greil R, Fox P, Wolff AC, Chan A, Winer EP, Pfeiler G, Miller KD, Colleoni M, Suga JM, Rubovsky G, Bliss JM, Mayer IA, Singer CF, Nowecki Z, Hahn O, Thomson J, Wolmark N, Amillano K, Rugo HS, Steger GG, Hernando Fernandez de Aranguiz B, Haddad TC, Perello A, Bellet M, Fohler H, Metzger Filho O, Jallitsch-Halper A, Solomon K, Schurmans C, Theall KP, Lu DR, Tenner K, Fesl C, DeMichele A, Mayer EL; PALLAS groups and investigators. Adjuvant Palbociclib for Early Breast Cancer: The PALLAS Trial Results (ABCSG-42/AFT-05/BIG-14-03). J Clin Oncol. 2022 Jan 20;40(3):282-293. doi: 10.1200/JCO.21.02554. Epub 2021 Dec 7. PMID 34874182
• Results publication: Mayer EL, Dueck AC, Martin M, Rubovszky G, Burstein HJ, Bellet-Ezquerra M, Miller KD, Zdenkowski N, Winer EP, Pfeiler G, Goetz M, Ruiz-Borrego M, Anderson D, Nowecki Z, Loibl S, Moulder S, Ring A, Fitzal F, Traina T, Chan A, Rugo HS, Lemieux J, Henao F, Lyss A, Antolin Novoa S, Wolff AC, Vetter M, Egle D, Morris PG, Mamounas EP, Gil-Gil MJ, Prat A, Fohler H, Metzger Filho O, Schwarz M, DuFrane C, Fumagalli D, Theall KP, Lu DR, Bartlett CH, Koehler M, Fesl C, DeMichele A, Gnant M. Palbociclib with adjuvant endocrine therapy in early breast cancer (PALLAS): interim analysis of a multicentre, open-label, randomised, phase 3 study. Lancet Oncol. 2021 Feb;22(2):212-222. doi: 10.1016/S1470-2045(20)30642-2. Epub 2021 Jan 15. PMID 33460574
• Results publication: Dieras V, Rugo HS, Schnell P, Gelmon K, Cristofanilli M, Loi S, Colleoni M, Lu DR, Mori A, Gauthier E, Huang Bartlett C, Slamon DJ, Turner NC, Finn RS. Long-term Pooled Safety Analysis of Palbociclib in Combination With Endocrine Therapy for HR+/HER2- Advanced Breast Cancer. J Natl Cancer Inst. 2019 Apr 1;111(4):419-430. doi: 10.1093/jnci/djy109. PMID 30032196

• Study Protocol and Statistical Analysis Plan (PDF, 2020-12-23)

• Evanthia Galanis, MD, Principal investigator, Alliance Foundation Trials, LLC.
• Erica Mayer, MD, Principal investigator, Dana-Farber Cancer Institute
• Angela DeMichele, MD, Principal investigator, University of Pennsylvania
• Michael Gnant, MD, Principal investigator, ABCSG, Medical University Vienna

NIH grants: 2014