A Phase II Trial Testing Oral Administration of Lucitanib in Patients With Fibroblast Growth Factor Receptor (FGFR)1-amplified or Non-amplified Estrogen Receptor Positive Metastatic Breast Cancer

Inclusion Criteria:

* Histologically confirmed breast adenocarcinoma.
* Presence of an accessible metastatic lesion for biopsy or at least one archived metastatic tumour sample.
* Prior first-line systemic therapy in the metastatic setting.
* Demonstrated progression of disease by radiological or clinical assessment.
* Female patient, aged ≥18 years old.
* Estimated life expectancy \>3 months.
* Normal Left ventricular function
* Adequate haematological, hepatic and renal functions.
* For women with childbearing potential, a negative pregnancy test prior to initiation of the study drug and willingness to use an effective contraception.
* Ability to swallow oral capsules or tablets.

Exclusion Criteria:

* More than two lines of chemotherapy with or without targeted therapy in the metastatic setting.
* Previous treatment with bevacizumab within 3 months of first dose of Investigational Medicinal Product.
* Active central nervous system metastases, cerebral oedema, and/or progressive growth.
* Patients with impaired cardiac function.
* Uncontrolled arterial hypertension
* Patients with history of thrombotic disorders or hereditary risk factors of thromboembolic events
* Serum potassium level below Lower Limit of Normal
* Uncontrolled hypothyroidism.
* Pregnant or breastfeeding women.