Rectal AdenocarcinomaPhase 2ULTIMATENCT07209215
ctDNA-Informed Management of Early-Stage Rectal Cancer
A Phase 2 study testing Signatera Genome ultra-sensitive ctDNA blood test + total neoadjuvant therapy (TNT) in people with Rectal Adenocarcinoma and Rectal Cancer, run by University of California, Davis at 1 site in United States.
Trial 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… Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Rectal Adenocarcinoma, Rectal Cancer, Early-stage Rectal Cancer
- What is being tested?
- Signatera Genome ultra-sensitive ctDNA blood test + total neoadjuvant therapy (TNT)
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 200 participants
- Where
- 1 siteUnited States
- Study dates
- Oct 2026to Dec 2028
- Phase
- Phase 2
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- 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.
Who cannot join
- 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
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United States1 site
University of California Davis Comprehensive Cancer Center
Sacramento, California, 95817
Office of Clinical Research, 916-382-6970, OCRReferral@health.ucdavis.edu
About this study
Official title: ULtra sensiTive ctDNA-Informed Management eArly-stage recTal cancEr (ULTIMATE)
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.
Read the detailed description
Two cohorts of participants will be enrolled: Cohort A (participants appropriate for receiving TNT) and Cohort B (TNT already performed at UC Davis Health or externally). At Time A after TNT is completed and based on ctDNA assay results, the clinical decision will be made to put participants into one of two arms: the ctDNA informed management arm (Watchful Waiting [WW] surveillance) or the post TNT SOC surgery arm; participants will be monitored for ctDNA positivity for up to 5 years.
- Conditions
- Rectal Adenocarcinoma, Rectal Cancer, Early-stage Rectal Cancer, Locally Advanced Rectal Adenocarcinoma
- Being tested
- Signatera Genome ultra-sensitive ctDNA blood test + total neoadjuvant therapy (TNT)
- Medical subject headings
- Rectal Neoplasms
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
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.
| Study group | Role | What they receive |
|---|---|---|
| ctDNA informed management arm (Watch and Wait surveillance) | Experimental | Not described Receives: Drug: Signatera Genome ultra-sensitive ctDNA blood test + total neoadjuvant therapy (TNT) |
| Post TNT SOC surgery arm | Experimental | Not described Receives: Drug: Signatera Genome ultra-sensitive ctDNA blood test + total neoadjuvant therapy (TNT) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Pathologic complete response (pathCR) rate (ctDNA Informed Management Arm)
Percent of participants with local regrowth within 2 years of total neoadjuvant therapy (TNT)
Measured: 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
Measured: 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.
Measured: Up to 2 years after TNT
Secondary outcomes (1)
Frequency of local regrowth (ctDNA Informed Management Arm)
Percentage of participants with local regrowth within 2 years of TNT
Measured: Up to 2 years after TNT
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted6 Oct 2025
- Study startOct 2026 (estimated)
- Primary completionMay 2028 (estimated)
- Study completionDec 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Rectal AdenocarcinomaStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 200 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University of California, Davis
- Sponsor type
- University, hospital or other
- Collaborators
- National Cancer Institute (NCI)
- Responsible party
- Sponsor
- Investigators
- Ankit Sarin, MD, Principal investigator, University of California, Davis
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07209215
- Sponsor's protocol ID
- UCDCC322
- Other IDs
- P30CA093373, NCI-2026-00131
- Acronym
- ULTIMATE
- Status last verified
- Aug 2026
- First submitted
- 30 Sep 2025
- Last updated
- 5 Aug 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No