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  • Cancer Type: Breast
  • Study Type: Treatment
  • NCT#: NCT05573555
  • Phase: Phase I/II
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  • Overview

    Study Title:

    Pfizer Umbrella Study - TACTIVE-U: An Interventional Safety and Efficacy Phase 1b/2, Open label Umbrella Study to Investigate Tolerability, PK, and Antitumor Activity of ARV-471 (PF-07850327), an Oral Proteolysis Targeting Chimera, in Combination with Other Anticancer Treatments in Participants Aged 18 Years and Over With ER+ Advanced or Metastatic Breast Cancer, Sub-Study B (ARV-471 in Combination with Ribociclib)


    The purpose of this clinical trial is to learn about the safety and effects of the study medicine (called ARV-471) when given together with other medicines for the potential treatment of advanced or metastatic breast cancer.


    Objectives To assess safety and tolerability of ARV-471 in combination with ribociclib in participants with ER+/HER2- A/MBC, to select a RP2D. To evaluate the overall safety profile. To evaluate antitumor activity of ARV-471 in combination with ribociclib. To evaluate the effect of ribociclib on PK ofARV-471

  • Treatments


    Chemotherapy (NOS)


    ARV-471 (); LEE011 (Ribociclib); Ribociclib ()

  • Inclusion Criteria

    • Histological or cytological diagnosis of ER+ and HER2- advanced/metastatic breast cancer that is not amendable to surgical resection with curative intent (>1% ER+ stained cells on the most recent tumor biopsy)
    • Prior anticancer therapies: up to 2 lines of prior therapies for advanced/metastatic disease; 1 line of any CDK4/6 inhibitor-based regimen is required (in any setting eg adjuvant, metastatic)
    • At least 1 measurable lesion as defined by RECIST v1.1
    • ECOG PS <1>
  • Exclusion Criteria

    • Visceral crisis at risk of life-threatening complications in the short term
    • Known history of drug-induced pneumonitis or other significant symptomatic deterioration of lung functions.
    • Newly diagnosed brain metastases, or symptomatic CNS metastases, carcinomatous meningitis, or leptomeningeal disease. Participants with a history of CNS metastases or cord compression are eligible if they have been > Definitively treated, clinically stable and discontinued anti-seizure medications and corticosteroids for at least 14 days prior to enrollment in the of study.
    • History of any other tumor malignancies within the past 3 years, except for the following: (1) adequately treated basal or squamous cell carcinoma of the skin; (2) curatively treated in situ carcinoma of the cervix.
    • Inflammatory breast cancer
    • Impaired cardiovascular function or clinically significant cardiovascular diseases
    • Concurrent administration of medications, food, or herb supplements that are strong inhibitors and strong/moderate inducers of CYP3A and drugs known to predispose to Torsade de Pointes or QT interval prolongation.
    • Renal impairment, not adequate liver function and/or bone marrow function
    • Known active infection

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