Inclusion Criteria:

- Post-menopausal women (either through bilateral oophorectomy or amenorrhoeic for 24
months)

- Histological confirmation of Breast Cancer with documented ER+ receptor status

- Safety run-in: Relapsing during/within 12 months of completion of a single regimen
of adjuvant endocrine therapy with non-steroidal AI and/ tamoxifen or progression
following 1st line endocrine therapy with non-steroidal AL

- Rand phase IIa: Received at least 1 prior endocrine therapy in the metastatic setting
or have relapsed during/ within 6 months of completion of adjuvant endocrine therapy
(either non-steroidal AI or tamoxifen or a combination of both). Chemotherapy
administered in the adjuvant setting is permitted.

- Rand phase IIa: Mandatory provision of tumour sample to confirm FGFR1 polysomy or
gene amplification. At least one measurable lesion that can be accurately assessed by
CT/MRI/x-ray at baseline and follow up visits

Exclusion Criteria:

- Prior exposure to exemestane (safety run-in) / fulvestrant (randomized phase IIa), or
any agent known to inhibit FGFRs.

- More than 1 prior regimen of chemotherapy for breast cancer

- ECG recordings that demonstrate significant abnormalities in cardiac rate, rhythm or
conduction

- History of hypersensitivity to active or inactive excipients of AZD4547 or exemestane
(safety run-in ) or fulvestrant (Randomized phase), including castor oil, or drugs
with a similar chemical structure or class to AZD4547 or exemestane or fulvestrant.

- Randomized phase IIa: bleeding/blood clotting conditions that would prevent the
administration of the fulvestrant injection into the buttocks