ASCENT-Study of Sacituzumab Govitecan in Refractory/Relapsed Triple-Negative Breast Cancer


About this study

This is an international, multi-center, open-label, randomized, Phase III study in patients with metastatic TNBC refractory or relapsing after at least 2 prior chemotherapies (including a taxane) for their metastatic disease. Patients meeting eligibility will be randomized 1:1 to receive either sacituzumab govitecan or treatment of physician choice (TPC), which needs to be selected prior to randomization from one of the 4 allowed regimens. Randomization will be stratified by number of prior chemotherapies for advanced disease (2-3 vs > 3) and geographical location (North America vs Europe). Patients will be treated until progression, unacceptable toxicity, study withdrawal, or death, whichever comes first. Tumor progression leading to treatment withdrawal will be assessed by the investigator. Starting with the initial dose of sacituzumab govitecan or TPC, CT scans (or MRI if contrast allergic) will be obtained at least every 8 weeks until the occurrence of progression of disease requiring discontinuation of further treatment.All patients, including those prematurely terminating study participation, will be followed every 4 weeks during the first year and every 8 weeks thereafter for survival follow-up.

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Inclusion Criteria:

  • Female or male patients, >18 years of age, able to understand and give written informed consent.
  • Histologically or cytologically confirmed TNBC per ASCO/CAP criteria, based on the most recent analyzed biopsy or other pathology specimen. Triple negative is defined as <1% expression for estrogen receptor (ER) and progesterone receptor (PR) and negative for human epidermal growth factor receptor 2 (HER2) by in-situ hybridization.
  • Metastatic disease documented by CT or MRI imaging.
  • Measurable disease by CT or MRI as per RECIST 1.1. Bone-only disease is not permitted.
  • Brain MRI must be done for patients with brain metastasis and patient must have had stable* CNS disease for at least 4 weeks. A maximum of 15% (N=74) of patients with brain metastases will be included in this trial.
  • "Stable" brain mets may be defined as:
    • Prior local treatment by radiation, surgery, or stereotactic surgery
    • Imaging – stable or decreasing size after such local treatment
    • Clinically stable signs and symptoms
    • ≥2 weeks from discontinuation of anti-seizure medication.
    • Corticosteroid (if needed) - dose should be stable, or decreasing for at least 2 weeks before randomization. Steroid dose should be 20 mg or less of prednisone/prednisolone daily, or equivalent of a different steroid.
  • At least 2 weeks beyond high dose systemic corticosteroids (however, low dose corticosteroids ≤ 20 mg prednisone or equivalent daily are permitted provided the dose is stable for 4 weeks).
  • Refractory to or relapsed after at least two prior standard of care chemotherapy regimens for unresectable, locally advanced or metastatic breast cancer (Appendix 1). (These regimens will qualify regardless of triple-negative status at the time they were given. There is no cap on the number of prior chemotherapies for locally advanced or metastatic disease and earlier adjuvant or neoadjuvant therapy for more limited disease will qualify as one of the required prior regimens if the development of unresectable, locally advanced or metastatic disease occurred within a 12-month period of time after completion of chemotherapy).
    • For patients with a documented germ-line BRCA1/BRCA2 mutation who received an approved PARP inhibitor, the PARP inhibitor can be used to meet the criteria for one of two prior standard of care chemotherapies.
    • All patients must have been previously treated with a taxane regardless of disease stage (adjuvant, neoadjuvant or advanced) when it was given. Patients who have contra-indications or are intolerant to taxanes are eligible provided that they received at least one cycle of a taxane and showed contra-indications or intolerance during or at the end of that cycle.
  • Eligible for one of the chemotherapy options listed as TPC (Eribulin, capecitabine, gemcitabine, or vinorelbine) as per investigator assessment.
  • ECOG performance score of 0 or 1 (Appendix 2). 
  • Adequate hematology without transfusional support (hemoglobin > 9 g/dL, ANC > 1,500 per mm3, platelets > 100,000 per mm3). Blood transfusion or growth factor support is not allowed within 14 days prior to screening labs.
  • Adequate renal and hepatic function (creatinine clearance of > 60 ml/min, may be calculated using Cockcroft-Gault equation; bilirubin ≤ 1.5 IULN, AST and ALT ≤ 2.5 x IULN or ≤ 5 x IULN if known liver metastases and serum albumin ≥3 g/dL). 
  • Recovered from all toxicities to Grade 1 or less by NCI CTCAE v4.03 (except alopecia or peripheral neuropathy that may be Grade 2 or less) at the time of randomization. Patients with Grade 2 neuropathy are eligible but may not receive vinorelbine as TPC.
  • Patients must have completed all prior cancer treatments at least 2 weeks prior to randomization including chemotherapy (includes also endrocrine treatment), radiotherapy and major surgery:
    • Prior antibody treatment for cancer must have been completed at least 3 weeks prior to randomization. 
  • Prior investigational agents are permitted, provided completion according to the timeframes above. 
  • Patients must have a life expectancy of 3-months or greater, in the opinion of the investigator.

Exclusion Criteria:

  • Women who are pregnant or lactating.
  • Women of childbearing potential or fertile men unwilling to use highly effective contraception during study and up to three months after treatment discontinuation in women of child-bearing potential and six months in males post last study drug.
    • Highly effective is defined as combined (estrogen and progestogen containing) hormonal contraception:
      • Oral, intravaginal, transdermal, progestin -only hormonal contraception associated with inhibition of ovulation: oral, injectable, implantable, intrauterine device (IUD), intrauterine hormone-releasing system (IUS), bilateral tubal occlusion, vasectomized partner, sexual abstinence);
      • Abstinence refers to 'True abstinence’ which means it is in line with the preferred and usual lifestyle of the patient;
      • Periodic abstinence (e.g., calendar, ovulation, symptotherma, post-ovulation methods);
      • Declaration of abstinence for the duration of exposure to study treatment and withdrawal are not acceptable methods of contraception.
  • Patients with Gilbert’s disease.
  • Patients with non-melanoma skin cancer or carcinoma in situ of the cervix are eligible, while patients with other prior malignancies must have had at least a 3-year disease-free interval.
  • Patients known to be HIV positive.
  • Patients with hepatitis B positive, or hepatitis C positive infection:
    • In patients with a history of HBV, hepatitis B core antibody (HBcAb) testing is required and if positive, then HB DNA testing will be performed and if positive the patient will be excluded.
  • Known history of unstable angina, MI, or CHF present within 6 months of randomization or clinically significant cardiac arrhythmia (other than stable atrial fibrillation) requiring anti-arrhythmia therapy.
  • Known history of clinically significant active COPD, or other moderate-to-severe chronic respiratory illness present within 6 months of randomization.
  • Prior history of clinically significant bleeding, intestinal obstruction, or GI perforation within 6 months of randomization.
  • Infection requiring antibiotic use within one week of randomization.
  • Patients with active chronic inflammatory bowel disease (ulcerative colitis, Crohn disease) and patients with a history of bowel obstruction.
  • Patients who have received a live vaccine within 30 days of randomization.
  • Patients who previously received irinotecan.
  • Rapid deterioration during screening prior to randomization, e.g. significant change in performance status, ≥ 20% decrease in serum albumin levels, unstable pain symptoms requiring modifications in analgesic management.
  • Other concurrent medical or psychiatric conditions that, in the Investigator’s opinion, may be likely to confound study interpretation or prevent completion of study procedures and follow-up examinations.



Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status Contact

Rochester, Minn.

Mayo Clinic principal investigator

Roberto Leon Ferre, M.D.

Closed for enrollment

Contact information:

Cancer Center Clinical Trials Referral Office

(855) 776-0015

More information


  • Standard chemotherapy is associated with low response rates and short progression-free survival among patients with pretreated metastatic triple-negative breast cancer. Sacituzumab govitecan-hziy is an antibody-drug conjugate that combines a humanized monoclonal antibody, which targets the human trophoblast cell-surface antigen 2 (Trop-2), with SN-38, which is conjugated to the antibody by a cleavable linker. Sacituzumab govitecan-hziy enables delivery of high concentrations of SN-38 to tumors. Read More on PubMed

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