RecruitingColon CancerdMMR Colorectal Cancer
Single Arm Study of Neoadjuvant Dostarlimab in Stage II and III Deficient Mismatch Repair Colon Cancers
Eligible age
18+ yrs
Accepts
All genders
Locations
2 states
Healthy volunteers
No
See if you qualify for this study
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About this study
This is a Phase II, single arm study looking at the rate of major clinical response and non-operative management in Stage II and III colon cancer after 18 weeks (up to 6 cycles) of neoadjuvant dostarlimab.
Sponsor: University of Iowa
You may qualify if…
- ✓ Capable of understanding and complying with the protocol requirements and have signed the informed consent document. Patients with mild cognitive impairment may be considered for enrollment in the study if their legally authorized representative provides written informed consent for the patient.
- ✓ 18 years or older in age
- ✓ Biopsy proven dMMR (by IHC), Stage II or III colon cancer per CT imaging correlation with AJCC 8th edition, 2017, amendable to en block surgical resection as determined by colorectal surgeon.
- ✓ Biopsy specimen for diagnosis of dMMR Colon cancer should have enough tissue for minimum 4 and max 6 adjacent unstained FFPE slides (4µm each) as determined by Protocol Pathologist Dr. Anthony Snow for CD3+ and CD8+ analysis. If there is not enough tissue present in original sample, a repeat colonoscopy and biopsy may be performed; otherwise patient is not eligible.
- ✓ Potentially surgically resectable Stage II or III patients who are willing to forgo surgical resection if study endpoints are met. Patient with easily manageable bowel changes amenable to laxatives or stool softeners as outpatient per assessment by colorectal surgery are allowed. (See exclusion criteria #2)
- ✓ ECOG performance status less than or equal to 1
- ✓ Absence of metastatic disease on CT CAP with Contrast within 28 days from treatment start
- ✓ Absolute neutrophil count greater than or equal to 1,500/µL
You may not qualify if…
- ✕ Synchronous primary tumor (i.e. more than 1)
- ✕ Obstruction or perforation requiring diverting ostomy or immediate resection, or bright red blood per rectum requiring urgent blood transfusion, from their primary tumor.
- ✕ Clinical T4b tumors
- ✕ Known hypersensitivity to dostarlimab components or excipients.
- ✕ Major surgery less than or equal to 3 weeks prior to initiating protocol therapy
- ✕ Received investigational therapy less than or equal to 3 months, or within a time interval less than at least 5 half- lives of the investigational agent, whichever is shorter, prior initiating protocol therapy.
- ✕ Heavy bleeding from the colon cancer tumors requiring PRBC transfusions that would require palliative surgical resection
- ✕ Concurrent, clinically significant, active malignancies within two years of study enrollment.
Where it's recruiting
Source: ClinicalTrials.gov · NCT05239546 · last updated 2026-06-12