A Phase 2 Study of PCS6422 With Capecitabine in Patients With Advanced or Metastatic Breast Cancer

Inclusion Criteria

• •1. Aged ≥18 years at Screening
• •2. Diagnosis of histologically confirmed breast cancer that is unresectable. The following subsets of breast cancer are included:
• •1. Patients with triple-negative breast cancer, advanced or metastatic
• •2. Patients with hormone receptor (HR) positive, ER positive, HER2 negative advanced or metastatic breast cancer
• •3. Has measurable disease in accordance with RECIST 1.1 obtained by imaging within 28 days prior to C1D1
• •4. Other therapies are not indicated (eg, resistant or intolerant to taxanes and/or an anthracycline-containing regimen) for treatment of advanced or metastatic breast cancer
• •5. Has a life expectance of at least 24 weeks
• •6. Has Eastern Cooperative Oncology Group Performance Status (ECOG PS) 0 or 1 at screening
• •7. Has adequate bone marrow, liver, and renal function as assessed by the following laboratory requirements conducted within 7 days before C1D1 (Note: labs will also be repeated pre-dose on C1D1 to confirm eligibility): a. Hemoglobin ≥9 g/dL (≥90 g/L) b. Adequate renal function by estimated glomerular filtration rate (eGFR) defined as a creatinine clearance \>50 mL/min (\>0.84 mL/s) (Cockcroft-Gault equation) and normalized to body surface area c. Peripheral absolute neutrophil count (ANC) of ≥1.5×109/L d. Platelet count of ≥100×109/L without growth factor/transfusion e. Total bilirubin \<1.5× upper limit of normal (ULN); or ≤3×ULN if the patient has Gilbert's disease f. Aspartate aminotransferase (AST) or alanine aminotransferase (ALT) \<2.5×ULN, with liver metastasis \<5×ULN g. International normalized ratio (INR) \<1.5 and prothrombin time (PT) ≤1.5×ULN, unless both of the following conditions are met: i. Patient is receiving anticoagulant therapy, and ii. PT or partial thromboplastin time (PTT) is within therapeutic range of intended use of anticoagulant h. Activated partial thromboplastin time (aPTT) ≤1.5×ULN, unless both of the following conditions are met: i. Patient is receiving anticoagulant therapy, and ii. PT or PTT is within therapeutic range of intended use of anticoagulants