ctDNA-Informed Management of Early-Stage Rectal Cancer

NCT07209215 | Not Yet Recruiting Phase 2 DMC FDA Drug

• 2 other identifiers: UCDCC322P30CA093373
• Study Type: interventional
• Target: 200
• Locations: 1 country
• Sites: 1

Brief Summary

This is a phase 2 pragmatic study to examine the utility of ctDNA-informed treatment management for participants with early-stage rectal cancer using the Signatera Genome assay. The primary aims are to 1) assess pathologic complete response (path CR) in the ctDNA informed management arm; 2) assess pathologic complete response (path CR) in the post total neoadjuvant therapy (TNT) standard of care (SOC) surgery arm; and 3) assess disease free survival (DFS) in the ctDNA informed management arm.

Conditions

Rectal Adenocarcinoma; Rectal Cancer; Early-stage Rectal Cancer; Locally Advanced Rectal Adenocarcinoma

Outcome Measures

Primary Outcomes (3)

• Pathologic complete response (pathCR) rate (ctDNA Informed Management Arm)

  Percent of participants with local regrowth within 2 years of total neoadjuvant therapy (TNT)

  Up to 2 years after TNT

• Pathologic complete response (pathCR) rate (Post TNT SOC Surgery Arm)

  Percent of participants with local regrowth within 2 years of TNT

  Up to 2 years after TNT

• Disease-free survival (DFS) rate (ctDNA Informed Management Arm)

  Median interval from first date of TNT to the first occurrence of locoregional failure, distant recurrence, a new invasive colorectal primary cancer.

  Up to 2 years after TNT

Secondary Outcomes (1)

• Frequency of local regrowth (ctDNA Informed Management Arm)

  Up to 2 years after TNT

Study Arms (2)

ctDNA informed management arm (Watch and Wait surveillance)

EXPERIMENTAL

Drug: Signatera Genome ultra-sensitive ctDNA blood test + total neoadjuvant therapy (TNT)

Post TNT SOC surgery arm

EXPERIMENTAL

Drug: Signatera Genome ultra-sensitive ctDNA blood test + total neoadjuvant therapy (TNT)

Interventions

Signatera Genome ultra-sensitive ctDNA blood test + total neoadjuvant therapy (TNT) DRUG

Use of Signatera Genome ultra-sensitive ctDNA blood test post-total neoadjuvant therapy (TNT) for ctDNA-informed treatment management of early-stage rectal cancer.

Post TNT SOC surgery arm; ctDNA informed management arm (Watch and Wait surveillance)

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Tumor tissue histologically confirming rectal adenocarcinoma that is available for Natera ctDNA assay.
• Cohort A only: Patients appropriate for receiving TNT including chemotherapy and chemoradiation.
• Cohort B only: TNT must have included at least 4 cycles of CAPEOX or 6 cycles of FOLFOX and at least 45 Gy in 25 fractions to the pelvis during chemoradiation.
• Patients ≥18 years of age at time of consent.
• Ability to understand and willingness to sign the informed consent form (ICF).
• Ability and stated willingness to adhere to the study visit schedule and protocol procedures/requirements.

You may not qualify if:

• Prior treatment for rectal cancer, except for cohort B.
• Evidence of distant metastatic disease on staging imaging (CT chest with abdominopelvic imaging by CT or MRI) within 8 weeks of enrollment.
• Patients on hemodialysis.
• Any condition that in the opinion of the investigator would interfere with the participant's safety or compliance while on trial

Sponsors & Collaborators

• University of California, Davis: lead
• National Cancer Institute (NCI): collaborator

Study Sites (1)

University of California Davis Comprehensive Cancer Center

Sacramento, California, 95817, United States

Location

MeSH Terms

Conditions

Rectal Neoplasms

Condition Hierarchy (Ancestors)

Colorectal Neoplasms; Intestinal Neoplasms; Gastrointestinal Neoplasms; Digestive System Neoplasms; Neoplasms by Site; Neoplasms; Digestive System Diseases; Gastrointestinal Diseases; Intestinal Diseases; Rectal Diseases

Study Officials

• Ankit Sarin, MD

  University of California, Davis

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Ankit Sarin, MD

CONTACT

(916) 734-3772; axsarin@health.ucdavis.edu

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: September 30, 2025
• First Posted: October 6, 2025
• Study Start: March 1, 2026
• Primary Completion (Estimated): November 1, 2027
• Study Completion (Estimated): May 1, 2028
• Last Updated: January 20, 2026

Record last verified: 2025-09

Locations

US (1)