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A Trial Using ARV-471 or Anastrozole in Post-Menopausal Women With Breast Cancer Prior to Surgery

Phase 2
Completed
Conditions
Breast Cancer
Interventions
Procedure: Surgical resection of breast tumor
Registration Number
NCT05549505
Lead Sponsor
Arvinas Inc.
Brief Summary

This trial is a Phase 2 neoadjuvant study evaluating ARV-471 or anastrozole in post-menopausal women with estrogen receptor positive/ human epidermal growth factor receptor 2 (ER+/HER2)- localized breast cancer.

Detailed Description

This is a Phase 2, open-label, randomized, non-comparative proof of concept study of ARV-471 or anastrozole in participants with ER+/HER2- breast cancer amenable to definitive surgical resection. The main goal of this study is to evaluate the biological activity of ARV-471 and anastrozole, respectively.

Recruitment & Eligibility

Status
COMPLETED
Sex
Female
Target Recruitment
152
Inclusion Criteria
  • Post-menopausal females ≥ 18 years.

  • Histologically or cytologically confirmed ER+ and HER2- breast cancer (per local assessment). ER and HER2 status must be documented:

    • ER+ disease, with ER staining of ≥ 10% of tumor cell nuclei by immunohistochemistry (IHC) per American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) guidelines.
    • HER2- disease by either IHC or in situ hybridization per ASCO/CAP guidelines.
    • Ki-67 score ≥ 5%, analyzed locally.
  • Clinical T1c-T4c, N0-N2, M0 breast cancer amenable to definitive surgical resection, without bilateral breast ductal carcinoma in situ or invasive breast cancer.

  • The primary tumor must be at least 1.5 cm by imaging.

  • Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1.

  • Willingness to undergo a screening biopsy, an on-treatment biopsy and surgical resection.

Exclusion Criteria
  • Any other active malignancy within 3 years prior to enrollment, except for adequately treated basal cell or squamous cell skin cancer, or cervical carcinoma in situ.
  • Any of the following in the previous 6 months: Myocardial infarction; Severe unstable angina; Coronary/peripheral artery bypass graft; Symptomatic congestive heart failure (New York Heart Association class III or IV); Cerebrovascular accident; Transient ischemic attack; Symptomatic pulmonary embolism or other clinically significant episode of thromboembolism.
  • Any of the following in the previous 6 months: Congenital long QT syndrome; Torsade de Pointes; Sustained ventricular tachyarrhythmia and ventricular fibrillation; Left anterior hemiblock (bifascicular block); Ongoing cardiac dysrhythmias of NCI CTCAE ≥ Grade 2; Atrial fibrillation of any grade (≥ Grade 2 in the case of asymptomatic lone atrial fibrillation).
  • corrected QT (Fridericia method) (QTcF) > 470 msec.
  • Active, uncontrolled bacterial, fungal or viral infection, including (but not limited to) hepatitis B virus (HBV), hepatitis C virus (HCV), and known human immunodeficiency virus (HIV) or acquired immunodeficiency syndrome (AIDS)-related illness.
  • Active inflammatory gastrointestinal disease, chronic diarrhea, known uncontrolled diverticular disease, or previous gastric resection or lap band surgery.
  • Cirrhosis meeting criteria for Child Pugh B and C.
  • Prior treatment for breast cancer including systemic therapy (eg, chemotherapy, hormonal therapy), radiation, surgery, or any investigational agents.
  • Any live vaccines within 14 days of planned start of first dose of study drug.
  • Major surgery (as defined by the Investigator) within four weeks of first dose of study drug.

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Arm A: ARV-471 (Experimental)ARV-471Participants received 200 mg ARV-471 (2\*100 mg tablets) once daily for approximately 5.5 months prior to undergoing surgical resection (no later than Cycle 6 Day 18 \[C6D18\] + 14 days).
Arm A: ARV-471 (Experimental)Surgical resection of breast tumorParticipants received 200 mg ARV-471 (2\*100 mg tablets) once daily for approximately 5.5 months prior to undergoing surgical resection (no later than Cycle 6 Day 18 \[C6D18\] + 14 days).
Arm B: AnastrozoleAnastrozoleParticipants received 1 mg Anastrozole tablet orally once daily for approximately 5.5 months prior to undergoing surgical resection (no later than C6D18 + 14 days).
Arm B: AnastrozoleSurgical resection of breast tumorParticipants received 1 mg Anastrozole tablet orally once daily for approximately 5.5 months prior to undergoing surgical resection (no later than C6D18 + 14 days).
Primary Outcome Measures
NameTimeMethod
Percent Reduction in Ki-67 Expression From Baseline to Day 15 in Tumor BiopsiesBaseline (during screening, prior to Day 1) and Day 15

Tumor biopsy Ki-67 expression (% of tumor cells that are positive for Ki-67) at baseline and Cycle 1 Day 15 (C1D15) was collected. Ki-67 expression was assessed by immunohistochemical staining in a central laboratory. The log-transformed Ki-67 after approximately 2 weeks of treatment as a percentage of the baseline value, ie, the ratio between the Ki-67 measurements obtained from C1D15 visit and baseline was modelled using a generalized linear model (GLM) with both stratification factors (ie, baseline Ki-67 score and the tumor size) and treatment as co-variates. The treatment effects were back transformed into geometric means and their Confidence Intervals. The percent change, in other words, relative reduction, of Ki-67 after 2 weeks of treatment is reported as the complement of the ratio between the Ki-67 measurement from C1D15 and baseline, that is 100% × (1 - geometric mean ratio between Ki-67 at C1D15 and Ki-67 at baseline).

Secondary Outcome Measures
NameTimeMethod
Number of Participants With Treatment Emergent Adverse Events (TEAEs), Serious TEAEs and TEAEs Leading to Study Drug DiscontinuationFrom signing of consent to minimum of 30 days after last administration of study drug (up to approximately 6.5 months)

An AE is any untoward medical occurrence in a participant or clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of study intervention. A serious adverse event (SAE) was an AE that resulted in any of the following outcomes: death; life threatening; persistent/significant disability/incapacity; initial or prolonged inpatient hospitalization; congenital anomaly/birth defect or was otherwise considered medically important. A TEAE is an AE that emerges or worsens on/after the first dose of ARV-471/Anastrozole to 30 days after the last administration of the study intervention (ie, study drug treatment or surgical resection, whichever occurs last).

Pathologic Stage at the Time of Surgical ResectionAt Cycle 6 Day 18 (approximately 5.5 months), each cycle is 28 days

Local pathological assessment of the tissue from surgical resection (performed after approximately 5.5 months of treatment), at minimum, included pathologic stage (ypT and ypN stage) as described in the Laboratory Manual. Participants were analysed based on the current American Joint Committee on Cancer (AJCC) staging system as follows:

* Pathologic Tumor - post-neoadjuvant therapy pathologic tumor categorization (ypT): (ypTx, ypT0, ypTis, ypT1mi, ypT1a, ypT1b, ypT1c, ypT2, ypT3, ypT4a, ypT4b, ypT4c).

* Pathological Lymph Nodes - post-neoadjuvant therapy pathologic node categorization (ypN): (ypNX, ypN0, ypN0(i+), ypN0(mol+), ypN1, ypN1mi, ypN1a, ypN1b, ypN1c, ypN2, ypN2a, ypN2b, ypN3, ypN3a, ypN3b, ypN3c).

* ypT0 / ypN0 indicates no evidence of disease and the progressive grades indicate increasing size of tumor and increasing area of lymph node involvement respectively and ypTx/ypNX indicates non-measurable disease.

Pathological Complete Response(pCR) Rate at the Time of Surgical ResectionAt Cycle 6 Day 18 (approximately 5.5 months), each cycle is 28 days

pCR is defined as no invasive cancer in the breast and sampled axillary lymph nodes following completion of neoadjuvant systemic therapy (ie, Pathologic Tumor - ypT = ypT0 or ypTis, and Pathologic Lymph Nodes - ypN = ypN0 in the current American Joint Committee on Cancer (AJCC) staging system). pCR rate is the percentage of participants with pCR.

Number of Participants With Modified Preoperative Endocrine Prognostic Index (mPEPI) Score of 0 at the Time of Surgical ResectionAt Cycle 6 Day 18 (approximately 5.5 months), each cycle is 28 days

Modified Pre-operative Endocrine Prognostic Index (mPEPI) score is an investigational prognostic tool used to predict the risk of breast cancer recurrence. It will be derived from factors assigned a numerical score following Neoadjuvant endocrine treatment (NET). The factors include pathologic tumor size, and lymph node status and Ki67 expression in the surgical specimen. Total mPEPI score (mPEPI\_T) per participant is the sum of mPEPI score of each factor.

mPEPI score of 0 indicates Pathological tumor size T1-T2, no lymph nodes and Ki67 level of 0%-2.7%, 1 indicates: Ki67 level \>2.7%-7.3%, 2 indicates Ki67 level \>19.7%-53.1% and 3 indicates: tumor sizeT3-T4, presence of lymph nodes and Ki67 level \>53.1%.

Breast Conserving Surgery (BCS) RateAt Cycle 6 (from Day 141 to Day 168), each cycle is 28 days

Breast conserving surgery (BCS) Rate is the percentage of participants received breast conserving surgery.

Radiographic Response Per Modified Response Evaluation Criteria in Solid Tumors (mRECIST) in Primary Tumor During Cycle 6At Cycle 6 (from Day 141 to Day 168), each cycle is 28 days

The number of participants with Complete Response (CR), Partial Response (PR), Stable Disease (SD), Progressive Disease (PD), Not Evaluable (NE) per mRECIST calculated. CR = disappearance of all target lesions, PR is \>=30% decrease in sum of diameters of target lesions, progressive disease (PD) is \>=20% increase in sum of diameters of target lesions, stable disease (SD) is \<30% decrease or \<20% increase in sum of diameters of target lesions.

Percentage Change From Baseline at Cycle 6 Day 1 in Caliper Measurement of the Primary TumorBaseline (Day 1) and Cycle 6 Day 1 (At Day 141), each cycle is 28 days

The percentage change from the baseline of the primary breast tumor size in physical exam calculated in caliper measurement. Caliper-based response is the maximum percentage decrease or minimum percentage increase if there is no decrease per participant.

Trial Locations

Locations (1)

Clinical Trial Site

🇪🇸

Zaragoza, Spain

Clinical Trial Site
🇪🇸Zaragoza, Spain

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