S1. Synopsis of study protocol.

Item	Description
ER, estrogen receptor; PR, progesterone receptor; HER2, human epidermal growth factor 2; ANC, absolute neutrophil count; AST, aspartate aminotransferase; ALT, alanine aminotransferase; AUC, area under the curve; 5-HT, 5-hydroxytryptamine; G-CSF, granulocyte colony-stimulating factor.
Study ID	CH-BC-012
Study title	Randomized phase III trial comparing dose-dense epirubicin and cyclophosphamide followed by paclitaxel with paclitaxel plus carboplatin as adjuvant therapy for triple-negative breast cancer
Protocol date	4/20/2011
Trial stage principal	Phase III
Investigator	Binghe Xu, M.D. & PhD. National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College. Email: xubinghe@medmail.com.cn; Qing Li, B.S.Med. National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College. Email: cheryliqing@126.com
Participating study left	National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
Objectives	To compare the efficacy and safety of dose-dense epirubicin and cyclophosphamide (ECdd) followed by paclitaxel (P) with dose-dense paclitaxel plus carboplatin (PCdd) as adjuvant therapy for patients with triple-negative breast cancer (TNBC) at high risk of recurrence Primary objective: • Compare 3-year disease-free survival (DFS) of early TNBC patients at high risk treated with PCdd to those treated with ECdd-P regimens Secondary objectives: • Compare 3-year overall survival (OS) in the same population • Compare the toxicity of the PCdd to the ECdd-P in patients with TNBC at high risk of recurrence
Study population	Patients with early TNBC at high risk of recurrence
Study design	This is a single-left, open label, randomized, comparative phase III trial. The trial includes two groups: ECdd-P and PCdd. Eligible participants will be randomly assigned in a 1:1 ratio to the PCdd group or the ECdd-P group. Randomization was conducted with no stratification factors. Eligible patients will be continually enrolled into the study until the total number of patients reached the planned sample size. The patients, medical staff and investigators were aware of treatment allocation. Sample size was determined based on a superiority test of 3-year DFS rate. To detect a difference of an approximate higher proportion of 0.10 between the two regimens (result of our preliminary clinical research demonstrated the proportion surviving in the ECdd-P regimen was 80.0%), an overall sample size of 133 subjects (66 in the ECdd-P arm and 67 in the PCdd arm) was calculated to achieve 80.0% power at a one-sided 0.050 significance level, with a 10% dropout rate (5% in each control/treatment arm). The accrual pattern across time periods was uniform (all periods equal). Primary and secondary efficacy analyses include the intent-to-treat (ITT) population of all randomly assigned patients. The safety analysis population includes all patients who received at least one dose of treatment.
Eligibility	Inclusion criteria: 1) Patient must accept the primary breast surgery; 2) Patients with histologically confirmed ER (−), PR (−) and HER2 (−),i.e., <1% positive tumor cells with nuclear staining in IHC and no HER2 overexpression; 3) Positive axillary lymph nodes; negative axillary lymph node with age <35 years or III grade or intravascular cancer embolus; 4) Age between 18 years to 65 years; 5) Able to give informed consent; 6) Patients with an Eastern Cooperative Oncology Group (ECOG) performance score of 0 or 1; 7) Not pregnant, and on appropriate birth control if of child-bearing potential; 8) Adequate bone marrow reserve with ANC >1.5×10 9/L and platelets >100×10 9/L; 9) Adequate renal function with serum creatinine <2.0× the upper limit of normal; 10) Adequate hepatic reserve with serum bilirubin <2.0× the upper limit of normal, AST/ALT <2× the upper limit of normal, and alkaline phosphatase < 5× the upper limit of normal. Serum bilirubin >2.0 is acceptable in the setting of known Gilbert’s syndrome; and 11) No active major medical or psychosocial problems that could be complicated by study participation. Exclusion criteria: 1) Received neo-adjuvant therapy; 2) cardiac dysfunction documented by an ejection fraction less than the lower limit of the facility normal by multi-gated acquisition (MUGA) scan, or 45% by echocardiogram; 3) uncontrolled medical problems; 4) evidence of active acute or chronic infection; 5) pregnant or breast feeding; or 6) hepatic, renal or bone marrow dysfunction as detailed above.
Sample size calculation	The target sample size was calculated based on the primary endpoint, i.e., 3-year DFS rate. To detect a difference of 0.13 between the two regimens (result of our preliminary clinical research demonstrated the proportion surviving in the ECdd-P regimen was 80.0%), an overall sample size of 133 subjects (66 in the ECdd-P arm and 67 in the PCdd arm) was calculated to achieve 80.0% power at a one-sided 0.050 significance level. The accrual pattern across time periods was uniform (all periods equal). The proportion of drop out in the control and treatment group was 0.1000 (each 0.05).
Randomization	Upon meeting the eligibility criteria, patients will be randomised under concealment, by the study lead investigator (Cancer Hospital, Chinese Academy of Medical Sciences), according to prespecified randomisation number lists to receive ECdd-P or PCdd.
Treatment	Administration: Patients in both study groups received treatment in 14-day cycles. Patients assigned to the PCdd arm received paclitaxel 150 mg/m2 on d 1 plus carboplatin AUC=3 on d 2 for 8 cycles. Patients assigned to the ECdd-P arm received epirubicin 80 mg/m2 divided in 2 d and cyclophosphamide 600 mg/m2 on d 1 for 4 cycles followed by paclitaxel 175 mg/m2 on d 1 for 4 cycles. Prophylactic antiemetic measures, including 5-HT3 receptor antagonists, and dexamethasone, were allowed. Premedication with dexamethasone and histamine antagonists was administered before paclitaxel to prevent hypersensitivity reactions. Prophylactic G-CSF 3 µg/kg in d 5−9 was given for each chemotherapy cycle.
Safety assessments and dose modifications	Safety assessments included 12-lead electrocardiograms, vital sign taking and clinical laboratory evaluations every cycle. Adverse events (AEs) were recorded at each treatment cycle until 28 follow-up d after the end of study visit. Toxicity was graded by using the National Cancer Institute Common Terminology Criteria for Adverse Events version 3.0 (NCI-CTCAE, version 3.0). Febrile neutropenia was managed according to institutional treatment guidelines in China. Toxicities were managed through dose delays of up to 3 weeks, and dose reductions were permitted in the following events: grade 4 hematological, grade 3 or 4 non-hematological, or other protocol-specified toxic effects.
Study drugs	Drug: epirubicin, cyclophosphamide, paclitaxel, carboplatin, G-CSF epirubicin 80 mg/m2 iv divide in 2 d cyclophosphamide 600 mg/m2 iv d 1 G-CSF 3 µg/kg in d 5−9 q14d ×4 cycles paclitaxel 175 mg/m2 iv d 1 G-CSF 3 µg/kg in d 5−9 q14d ×4 cycles paclitaxel 150 mg/m2 iv d 1 carboplatin AUC=3 iv d 2 G-CSF 3 µg/kg in d 5−9 q14d ×8 cycles.
Concomitant medications	1. Antiemetics can be prescribed to patients who are vomiting due to administration of treatment drug(s); 2. Patients experiencing peripheral neuropathy can be treated with neurotropic supplements such as duloxetine, vitamin B, etc.; 3. Analgesics can be used for patients who have pain affecting quality of life; 4. Patients with constipation, diarrhea, or other conditions can be treated using appropriate medication for their respective condition; 5. Prophylactic antiemetic measures, including 5-HT3 receptor antagonists, and dexamethasone, were allowed. 6. Premedication with dexamethasone and histamine antagonists was administered before paclitaxel to prevent hypersensitivity reactions.
Outcome measures	Primary outcome measure: The primary endpoint is 3-year DFS rate. DFS was calculated from the date of randomization to the date of the first local/distant recurrence (without second primary malignancies), according to Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. Secondary outcome measures: Secondary endpoints include 3-year OS (defined as the time from randomization to death due to any cause) and safety of the treatment. Toxicity was graded by using the NCI- CTCAE, version 3.0.
Safety parameters	AEs, vital signs and clinical laboratory tests
Statistical analysis	All statistical analyses were performed using the Statistical Package for the Social Sciences (SPSS) software (Version 22.0; IBM Corp., New York, USA). Data on clinical characteristics, chemotherapy, recurrence, and survival were analyzed. Data were presented as the number (%) or the mean standard deviation. Continuous variables were compared using the Student’s t test, while categorical variables were compared using the χ2 or Fisher’s exact test. The proportion of patients remaining event-free over time will be displayed using the Kaplan-Meier method and analyzed using a two-sided log-rank test. All statistical tests were two-sided, and a P value of <0.05 was considered statistically significant. The safety population will include all patients who received at least one dose of treatment. For safety analysis, AEs will be coded using the Medical Dictionary for Regulatory Activities (MedDRA). Analysis of AEs will be based on treatment-emergent adverse events (TEAEs). TEAEs are AEs not present prior to medical treatment, or are already present and worsen either in intensity or frequency following treatment. The incidence rate of TEAEs will be described according to system organ class (SOC) and preferred term (PT). Meanwhile, serious AEs (SAEs) and AEs leading to study discontinuation will be similarly summarized and tabulated. Laboratory tests will be analyzed using descriptive statistical analysis.
Follow-up	All treated patients will be followed-up with once every 3 months to collect survival information for DFS and OS. Patients who discontinue treatment due to any causes will be followed-up with once every 3 months until disease recurrence or death. After disease recurrence, patient follow up can be conducted by phone or as general clinical visits until death.