Abstract 119P
Background
Neratinib is approved based on the phase III ExteNET study in Europe since 2018 to treat adult patients with Hormone Receptor-positive/Human Epidermal Growth Factor Receptor 2-positive (HR+/HER2+) early-stage breast cancer (eBC) completing adjuvant trastuzumab-based therapy <1 year ago (EU label). A 2017 Early Access Program (EAP) granted neratinib access to patients awaiting product availability. The eBC treatment landscape has evolved since ExteNET, and there is a need to assess neratinib safety and effectiveness in the recent treatment landscape.
Methods
NEAR is a retrospective, observational study in Belgium, Croatia, France, Italy, and Spain in adults with HER2+ eBC receiving ≥1 dose of neratinib in the context of the EAP between Aug 1, 2017, and Dec 31, 2020. Patient characteristics were presented in 2023.1 Here we present data on neratinib treatment patterns, safety, and 2-year effectiveness.
Results
As of Jan 31, 2023, 108 patients were included in the full analysis set (FAS), of which 92 were HR+ and 74 met the EU label criteria; median follow up was 28 months. Key patient characteristics are summarised in the table. Initial neratinib dose was 240 mg in 87% of both the FAS and the EU label subgroup; the rest received <240 mg. The most common adverse event (AE) was diarrhoea (all grades/grades 3–4: 58%/8% in the FAS; 53%/8% in the EU label subgroup), followed by other gastrointestinal AEs. Prophylactic antidiarrhoeal treatment was given in 44% of the FAS and in 47% of the EU label subgroup. At 2 years, in the HR+ and EU label subgroups, invasive/distant disease-free survival were 93%/94% and 95%/96%, respectively; overall survival was 98% and 97%. No central nervous system metastases were observed. Table: 119P
Key patient characteristics1, pre-treatments received1, and neratinib therapy patterns
| FAS (N=108) | EU label subgroup (n=74) | |
| Median age [min, max], years | 48 [30, 72] | 49 [30, 72] |
| Pre-menopausal, % | 37 | 41 |
| Stage I, %Stage II + III, %Missing, % | 17749 | 157411 |
| High recurrence risk profile‡, % | 81 | 81 |
| Prior neoadjuvant therapy, % | 58 | 65 |
| Prior anti-HER2 adjuvant therapy, %Of which on trastuzumab, % | 9188 | 9190 |
| Median months [min, max] from adjuvant therapy to neratinib initiation | 4.6 [0.3, 24] | 3.2 [0.3, 12] |
| Median [min, max] months on neratinib | 12.3 [0.03, 16] | 12.1 [0.3, 16] |
‡Stage II/III or N+ or no pathologic complete response
Conclusions
This study provides additional data supporting the use and management of extended adjuvant neratinib in clinical practice.
1. De Laurentiis et al. 2023. ESMO Congress, Poster #283.
Clinical trial identification
NCT05599334.
Editorial acknowledgement
Acknowledgements: Medical writing and editorial assistance were provided by Rebecca Hopkins via IQVIA, Cristiana Miglio of IQVIA and Nathaniel Grubbs of IQVIA, funded by Pierre Fabre.
Legal entity responsible for the study
Pierre Fabre Laboratories.
Funding
Pierre Fabre Laboratories.
Disclosure
T. Silovski: Financial Interests, Personal and Institutional, Principal Investigator: University Hospital Center Zagreb. A. Cano Jimenez: Financial Interests, Institutional, Invited Speaker: Hospital of Jaén. M. Krizic: Financial Interests, Personal, Invited Speaker: Roche, Servier, Medicopharmacia, Pierre Fabre. N. Dedic Plavetic: Financial Interests, Personal and Institutional, Advisory Role: University Hospital Center Zagreb. X. Gonzalez Farre: Financial Interests, Personal, Invited Speaker: Novartis, Pierre Fabre. A.L. Guerrero Zotano: Non-Financial Interests, Personal, Invited Speaker: Pierre-Fabre. C.J. Cabasag: Non-Financial Interests, Institutional, Other, Epidemiology Lead: IQVIA. O. Romano: Financial Interests, Personal and Institutional, Advisory Board: Daiichi Sankyo, Pfizer, MSD, Gilead, Amgen. M. De Laurentiis: Financial Interests, Personal, Invited Speaker: Novartis, Roche, Seagen, Gilead, Daiichi Sankyo, AstraZeneca, Pfizer. All other authors have declared no conflicts of interest.