1. Abstract OT2-6-01: Phase 2 study of palbociclib (CDK 4/6 inhibitor) for ER positive, HER2- negative post-menopausal advanced breast cancer patients recurring after hormonal therapy (to reverse endocrine resistance - TREnd trial)
- Author
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M Koehler, Marc Buyse, Silvia Cappadona, Giuseppe Curigliano, Luca Malorni, Giovanni Sanna, Laura Biganzoli, O. Siclari, A. Di Leo, Chiara Biagioni, Alessandro Marco Minisini, Luca Boni, Marta Pestrin, C. Guarducci, I. Migliaccio, and D Baldari
- Subjects
Gynecology ,Oncology ,Cancer Research ,medicine.medical_specialty ,Fulvestrant ,business.industry ,Letrozole ,Cancer ,Phases of clinical research ,Palbociclib ,medicine.disease ,Internal medicine ,medicine ,Clinical endpoint ,Hormonal therapy ,business ,Off Treatment ,medicine.drug - Abstract
Background: Palbociclib (PD-0332991) is an orally active, potent and highly selective inhibitor of CDK4/6 that prohibits progression of the cell cycle from G1 into S phase and has shown activity in ER positive breast cancer in vivo and in vitro. Recently, in phase 2 settings, palbocilcib extended PFS in combination with letrozole as first-line hormonal treatment for advanced breast cancer (ABC) (Finn R.S. et al. Cancer Res., Dec 2012; 72: S1-6) and showed single agent activity in patients with ER positive ABC relapsed to several lines of therapy (DeMichele A. et al., ASCO 2013). Given pre-clinical evidence on the relevance of Cyclin D-CDK4/6-E2F signalling in the development of acquired resistance to hormonal therapy, CDK4-6 inhibition might be a strategy to overcome resistance in tumors who have progressed after hormonal therapy for metastatic disease. Study design: This is an investigator initiated, open-label, multicenter, randomized, Phase 2 trial for patients with ER+ HER2 negative ABC who have experienced progression on first or second line hormonal therapy. Other eligibility criteria include: ≤1 previous line of chemotherapy for ABC; measurable disease; and available archival tumor tissue for translational studies. Consenting patients are randomized (1:1) to receive, until progression of disease, unacceptable toxicity or consent withdrawal, either ARM A) palbociclib 125 mg/d orally for 3 weeks followed by 1 week off treatment or ARM B) palbociclib in combination with the hormonal therapy to which the patient has experienced progression in the previous line of treatment (anastrozole 1 mg/d, letrozole 2.5 mg/d, exemestane 25 mg/d, fulvestrant 500mg/4 weeks). Patients are stratified according to: number or prior lines of hormonal therapy (1 vs. 2); disease site (visceral vs. non visceral); duration of prior line of hormonal therapy (>6 vs. ≤6 months); treating center. The primary endpoint is clinical benefit (CB) (i.e. complete response, partial response, stable disease≥ 24 weeks), based on local assessment of response using RECIST 1.1 criteria. Key secondary endpoints are: objective response rate, duration of response, time to progression, progression-free survival, overall survival and assessment of exploratory tissue markers of response. Statistical methods: A two-stage optimal phase 2 design is used to assess the activity of each of the two treatment regimens. Assuming P0≤20% (inactivity), P1≥ 40% (activity) and α = 10%, a sample size of 50 evaluable patients per treatment arm is required for a statistical power equal to 90%. In case of inactivity, enrolment could be stopped in each arm after 25 evaluable patients. This study does not provide adequate power for a two arm comparison. Target accrual: the study is actively recruiting in 3 Italian centers and is expected to involve additional 7 centers in Italy by the end of 2013. The first patient was enrolled in October 2012 and, as per June 2013, a total of 9 patients have been enrolled, 8 remain on treatment. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr OT2-6-01.
- Published
- 2013