Signatera-Guided CDK4/6 Inhibitor Therapy in Breast Cancer

Conditions

• Breast Neoplasms
• Carcinoma, Ductal, Breast
• Receptors, Estrogen (for ER-positive Requirement)

Eligibility Criteria

Sex

ALL

Age

18 Years - N/A

Healthy Volunteers

Not accepted

Interventions

• ctDNA-Guided Treatment Strategy — DEVICE
  Circulating tumor DNA testing using Signatera Genome assay is performed every 3 months for up to 4 years to guide timing of CDK4/6 inhibitor initiation. Participants with positive ctDNA results initiate CDK4/6 inhibitor therapy (ribociclib or abemaciclib) plus standard endocrine therapy for a minimum of 2 years. Participants with negative ctDNA results continue endocrine therapy alone with ongoing surveillance. CDK4/6 inhibitor selection and endocrine therapy regimen per the physician's choice following standard-of-care guidelines.

Study Details

The purpose of this study is to evaluate the efficacy and safety of ctDNA-guided initiation of CDK4/6 inhibitor therapy using the Signatera™ Designed on Genome test (referred to as "Signatera Genome") in participants with intermediate-risk HR+/HER2- early-stage breast cancer. Based on ctDNA test results, participants will either start CDK4/6 inhibitor therapy in addition to hormone therapy or continue hormone therapy with ongoing ctDNA surveillance. This study will compare outcomes to historical controls from the NataLEE trial to determine whether ctDNA-guided timing maintains efficacy while reducing unnecessary treatment. Participants will be followed for up to 9 years with regular blood draws, hormone therapy, imaging as needed, and quality-of-life assessments.

Key Dates

First listed

Oct 9, 2025

Start date

May 8, 2026

Status verified

Aug 2026

Primary completion

May 15, 2032

Completion

Dec 30, 2037

Study Design

Enrollment

725 participants (estimated)

Allocation

NA

Intervention model

SINGLE_GROUP

Primary purpose

TREATMENT

Arms

• Experimental: ctDNA-Guided Therapy
  All participants receive circulating tumor DNA (ctDNA) testing using Signatera Genome every 3 months to guide treatment decisions. Participants with positive ctDNA results initiate CDK4/6 inhibitor therapy (ribociclib or abemaciclib) in addition to standard endocrine therapy. Participants with negative ctDNA results continue endocrine therapy alone with ongoing ctDNA surveillance. All participants continue their assigned treatment pathway until disease progression, unacceptable toxicity, or study completion.

Primary Outcome Measure

Invasive Disease-Free Survival [ Time Frame: From the date of surgery up to 9 years ]

Central Contacts

• Chelsea Nihill, MS
  706-726-6935
  [email protected]
• Jessica Reyes, BS
  844-778-4700
  [email protected]

Locations (49)

Find similar trials in Phoenix, AZ

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