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Phase III study evaluating palbociclib, a cyclin-dependent kinase 4/6 inhibitor, in patients with hormone receptor-positive, HER2-normal primary breast cancer with high relapse risk after neoadjuvant chemotherapy.

Disease site: Breast cancer

Treatment modality: Systemic therapy (palbociclib)

Status: Closed

Trial details

PENELOPEB is a phase III international, multicentre, randomised, placebo-controlled, double-blind trial comparing the efficacy and safety of adding palbociclib to standard hormone therapy vs standard hormone therapy alone for the treatment of breast cancer patients with an increased risk of relapse after having received chemotherapy prior surgery.

In total 1,100 women from 13 countries are expected to take part. In the UK, 35 patients will be recruited over a two-year period. Participants will be randomised to one of two treatment groups:

  • Palbociclib + standard hormone therapy; or
  • Placebo + standard hormone therapy.

Participants will receive trial treatment for one year and will continue to receive standard hormone therapy for a total of at least five years.

Further information

UK Coordinating Investigator: Dr Andreas Makris (East and North Hertfordshire NHS Trust)

ICR-CTSU Scientific Lead: Professor Judith Bliss

Trial management contact: [email protected] identifier: NCT01864746

Sponsor: German Breast Group (GBG)

Funding: Pfizer

View PENELOPE-B on the National Institute for Health Research website: NIHR - Be Part Of Research

A link to a plain English summary of the trial will be added once available.

The German Breast Group (GBG) website provides information on PENELOPEB in German.

Publications and presentations

Loibl S, Marmé F, Martin M, Untch M, Bonnefoi H, Kim SB, Bear H, McCarthy N, Melé Olivé M, Gelmon K, García-Sáenz J, Kelly CM, Reimer T, Toi M, Rugo HS, Denkert C, Gnant M, Makris A, Koehler M, Huang-Bartelett C, Lechuga Frean MJ, Colleoni M, Werutsky G, Seiler S, Burchardi N, Nekljudova V, von Minckwitz G. Palbociclib for Residual High-Risk Invasive HR-Positive and HER2-Negative Early Breast Cancer-The Penelope-B Trial. J Clin Oncol. 2021 Apr 1:JCO2003639. doi: 10.1200/JCO.20.03639. Epub ahead of print. PMID: 33793299. 

Clinical trials

Division of Clinical Studies

The division carries out or coordinates high-quality trials and translational research at both an early phase – typically to test new targeted drugs – and a later stage.