119TiP A multicenter, open-label, single-arm, non-interventional real-world study to investigate the treatment patterns of neratinib in HER2-positive early breast cancer (EBC) in China: NER-Tree study

Neratinib is an oral, irreversible tyrosine kinase inhibitor of HER1, HER2 and HER4. In China, neratinib was approved in 2020 in the extended adjuvant treatment for HER2+ EBC adult patients who completed prior adjuvant trastuzumab-based therapy. Neratinib is currently the only approved anti-HER2 extended adjuvant therapy for HER2+ EBC. The ExteNET phase III trial, that included patients after adjuvant trastuzumab, has provided concrete efficacy evidence of neratinib in the extended adjuvant setting, but the adjuvant treatment landscape has changed since. Diarrhoea was the most common grade 3 adverse event observed without mandated antidiarrheal prophylaxis (39,8 %). With the evolving landscape of adjuvant treatments, there is a great need to identify real-world treatment patterns of neratinib in HER2+ EBC, its use in clinical practice, its effectiveness and safety data in patients in China. This is a multi-center, open-label, single-arm, non-interventional study in patients with HER2+ EBC in China. 500 patients in 30 centers who completed adjuvant trastuzumab based treatment and scheduled to receive 1-year of extended adjuvant neratinib will be included. Patients will undergo 12 months of extended adjuvant neratinib treatment and 12 months follow-up. Due to its observational nature, treatment decisions will be independent of the registration to the study. The primary objective aims to describe the real-world treatment patterns with neratinib among HER2+ early-stage breast cancer patients. Primary endpoints are patterns of adjuvant treatment, including patient demographics, characteristics, and different prior adjuvant treatments; and patterns of neratinib use as extended adjuvant treatment. Secondary endpoints include incidence, type, severity, and action taken of all grades of AE of special interest. Exploratory endpoints are characterization of recurrence patterns and assessment of self-reported HRQoL. As of 10 Jan 2023, 49 patients have been enrolled from 14 initiated sites. NCT05491057. Medical writing support was provided by Buffy Li, Beijing MetHealth Technology Co., Ltd. Pierre Fabre Medicament. Pierre Fabre Medicament.