Clinical trial NCT06830239: Phase II Study of Neoadjuvant Dostarlimab in Patients With Untreated T3-4N0-2 or Stage III pMMR/MSS Resectable Colon Cancer
Official title: Early Phase II Exploratory, Open-Label, Non-Randomized Study of Neoadjuvant Dostarlimab Monotherapy in Participants With Untreated T3-4N0-2 or Stage III pMMR/MSS Resectable Colon Cancer
Study type: INTERVENTIONAL
Overall status: NOT_YET_RECRUITING
Phase: PHASE2
Conditions: Colon Cancer Stage III
Keywords: Colon Cancer
Neoadjuvant
pMMR/MSS
Resectable
Lead sponsor: Universitaire Ziekenhuizen KU Leuven
Sponsor class: OTHER
First posted: 2025-02-17
Enrollment: 10
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: BASIC_SCIENCE

Brief summary: Dostarlimab belongs to a class of drugs called PD-1 inhibitors that use your own immune system to treat cancer (immunotherapy). It is designed to stop cancer from growing by helping your immune system recognize and fight the cancer. This investigational medicinal product (IMP) has been approved by the Belgian authorities, but not for the treatment of colon cancer.

It is known that a small number of patients with pMMR/MSS colon cancer may have significant response to medication of this type (immunotherapy) depending on each person's biology.

Trial intervention for all patients will be neo-adjuvant dostarlimab 500 mg IV, given alone by intravenous infusion. Two administrations of dostarlimab are foreseen, at three weeks interval, before surgery for your colon cancer. It has not yet been proven that this treatment can cure, improve or stabilise your disease or condition.

The study aims to investigate specific molecular changes in tumour and blood after dostarlimab monotherapy administered and before surgery which could be associated with improved response to conventional treatment in some patients. If you decide to participate, as the duration of treatment with dostarlimab is 6 weeks, surgery may be slightly delayed compared to patients that are not treated with dostarlimab and go directly for surgery. It remains uncertain if this is beneficial in your personal situation but some patients might experience significant response. The risks have been carefully assessed and the potential benefits for some patients are considered important and justify undertaking the treatment.

Subsequent therapy after surgery remains at the discretion of the treating physician.

The duration of a patient on trial will last up to 4 months from the first dose of dostarlimab and afterwards 2 years of follow up is applicable.


Eligibility criteria: Inclusion Criteria:

* at least 18 years of age and capable of giving informed consent
* primary adenocarcinoma colon cancer than can be removed surgically, staged cT3-4, cN0-2, cM0 or stage III
* tumour expresses an MMR proficient/microsatellite stable called MSS
* tissue samples from tumour and colon mucosa available for molecular analyses
* capable of receiving immunotherapy
* adequate general health status and organ function (blood tests)

Exclusion Criteria:

* no prior cancer treatment
* not pregnant and using effective contraception if applicable

Primary outcomes:
measure: Multi-omic exploration
timeFrame: From enrollment to the last FU visit of the patient for blood (2 years). From baseline to surgery for tissue (12-15 weeks). Data will be reported at the final study report (max 3 years from study start).
Secondary outcomes:
measure: Safety analysis
timeFrame: Continuous
measure: Pathological response
timeFrame: Pathological tumor staging and response assessment is at surgery
measure: Survival
timeFrame: From enrollment till last FU visit of patient (2 years). Data will be reported at the final study report (max 3 years from study start).
Other outcomes:
Locations:
city: Leuven
country: Belgium
facility: UZLeuven
Study officials:
affiliation: Universitaire Ziekenhuizen KU Leuven
name: Sabine Tejpar, MD
role: PRINCIPAL_INVESTIGATOR
References: