A Phase 2 Study of TAS-120 in Metastatic Breast Cancers Harboring Fibroblast Growth Factor Receptor (FGFR) Amplifications

Protocol # :
Metastatic Breast Cancer
FGFR 1 High Amplification
FGFR2 Amplification
Disease Sites
Principal Investigator
Giordano, Antonio
Site Investigator
Bardia, Aditya
Desai, Neelam
Site Research Nurses
Cung, Connie
Jeon, Maryangel, H.
Sheehan, Susan

Trial Description

The purpose of the trial is to evaluate a patient's response to a Fibroblast Growth Factor
Receptor (FGFR) inhibitor, futibatinib (TAS-120), used either alone or in combination with
the hormonal therapy, fulvestrant. This study will be conducted in patients with metastatic
breast cancer who have specific Fibroblast Growth Factor Receptor gene abnormalities and who
have previously received conventional therapies to treat their breast cancer, or who are not
able to tolerate certain cancer therapies. This study will also evaluate the safety of taking
futibatinib, or futibatinib and fulvestrant, by learning about the potential side effects.

Eligibility Requirements

Inclusion Criteria:

1. Provide written informed consent

2. Age ≥ 18 years of age

3. Histologically or cytologically confirmed recurrent locally advanced or metastatic
breast cancer not amenable to treatment with curative intent, and the following cohort
specific criteria:

A. Cohort 1

- HR+ HER2- breast cancer harboring an FGFR2 gene amplification.

- Measurable disease per Response Evaluation Criteria in Solid Tumors (RECIST)
Version 1.1

- Has received 1-3 prior endocrine-containing therapies and up to 2 prior
chemotherapy regimens for advanced/metastatic disease

- Has received prior treatment with a CDK4/6 inhibitor or is ineligible for such

B. Cohort 2

- TNBC harboring an FGFR2 gene amplification

- Measurable disease per RECIST 1.1

- Has received at least 1 prior chemotherapy or chemotherapy/immunotherapy
(PD-L1/PD-1 inhibitors) regimen for advanced/metastatic disease

C. Cohort 3

- TNBC or HR+ HER2- breast cancer harboring an FGFR2 gene amplification

- Non measurable, evaluable disease per RECIST 1.1. Patients with bone-only disease
must have lytic or mixed lytic-blastic lesions

- Other criteria for either HR+ HER2- breast cancer or TNBC should be met as
described for Cohort 1 and 2, respectively

D. Cohort 4

- HR+ HER2- breast cancer harboring an FGFR1 high-level gene amplification

- Measurable disease per RECIST 1.1

- Has received 1-2 prior endocrine-containing therapies and no more than 1 prior
chemotherapy regimen for advanced/metastatic disease. Prior treatment with
fulvestrant is not permitted.

- Has received prior treatment with a CDK4/6 inhibitor or is ineligible for such

- Pre/peri-menopausal patients must be on goserelin

4. Eastern Cooperative Oncology Group (ECOG) performance status 0 or 1

5. Archival or (preferably) fresh tumor tissue must be available

6. Adequate organ function

Exclusion Criteria:

1. History and/or current evidence of any of the following disorders:

1. Non-tumor related alteration of the calcium-phosphorus homeostasis that is
considered clinically significant

2. Ectopic mineralization/calcification, including but not limited to soft tissue,
kidneys, intestine, or myocardia and lung, considered clinically significant

3. Retinal or corneal disorder confirmed by retinal/corneal examination and
considered clinically significant

2. Prior treatment with an FGFR inhibitor

3. A serious illness or medical condition(s)

4. Brain metastases that are untreated or clinically or radiologically unstable

5. Pregnant or lactating female