Based on the pivotal PALOMA trials investigating the combination of the CDK4/6 inhibitor palbociclib with letrozole or with fulvestrant after prior endocrine therapy, extended European approval was granted for this patient population to receive palbociclib in combination with any aromatase inhibitor or with fulvestrant after prior endocrine therapy. The prospective multi-centre phase 2 study INGE-B was designed to a) investigate the combination of palbociclib with letrozole or with fulvestrant in accordance with the PALOMA trials in Germany and b) to obtain so far lacking data on the combination of palbociclib with the aromatase inhibitors exemestane or anastrozole.
In total, 360 patients with locally advanced, inoperable or metastatic HR+/HER2- breast cancer were recruited at 82 sites across Germany. Eligible patients are treated with palbociclib either in combination with letrozole, anastrozole, exemestane or fulvestrant as first-line therapy or in combination with letrozole or fulvestrant as later-line therapy. Primary objective is the clinical benefit rate (CBR), defined as the percentage of patients with response or stable disease at week 24. Key secondary endpoints include progression-free survival (PFS), overall survival (OS), overall response rate (ORR) and safety. Quality of life, fatigue, anxiety and depression are assessed with validated questionnaires. Data were analysed for each treatment group separately with descriptive statistics.
The first interim analysis of the INGE-B study was scheduled to analyse data of patients receiving palbociclib and letrozole in first or later line. Between 09/2016 and 01/2018, 63 first- and 59 later-line patients were enrolled at 38 sites and observed for at least 6 months of treatment, unless discontinued earlier for disease progression or any other reason. Baseline patient and tumour characteristics will be presented. Efficacy in terms of CBR and best response and treatment-emergent adverse events will be described.
The results of the first interim analysis of the INGE-B study will be discussed with respect to data from the PALOMA 1/2 trials.
Clinical trial identification
Legal entity responsible for the study
D. Lüftner: Membership on an advisory board or board of directors, remunerations: Amgen, Pfizer, Eli Lilly, Celgene, Loreal. A. Welt: Membership on an advisory board or board of directors: Roche, Pfizer, Novartis. All other authors have declared no conflicts of interest.