Under construction – not a live service
Sign in
Taking peoplePhase 2

Pembrolizumab and porustobart before surgery for colon cancer that can be removed

Tests pembrolizumab with porustobart before surgery in adults with colon cancer.

Key facts

Who runs it
Solstice Oncology, Inc.
Where
Aberdeen, Cardiff, Glasgow, Leeds, and London, United KingdomSee the 5 sitesAlso in 5 other countries, 23 sites
Registry title
Neoadjuvant Pembrolizumab and Porustobart in Resectable pMMR/MSS Colon Cancer
Status
Recruiting
Phase
Phase 2
People taking part
100 people, planned
Starts
30 Nov 2026
Expected to end
30 Sept 2029
Type of study
Interventional, 2 groups
Treatments tested
  • Pembrolizumab
  • Porustobart
Record updated
12 November 2026

Who can take part

AI summary

From the trial's eligibility criteria. Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.

The trial is looking for adults with colon cancer that can be removed by surgery and has not spread. The tumour must be pMMR/MSS.

Age
18 years or older
Sex
All sexes can join
Disease stage
Adenocarcinoma of the colon, any T3 or T4, N any, M0, able to be removed by surgery. The rectosigmoid counts as colon.
Earlier treatment
No earlier treatment with immune drugs that target CTLA-4, PD-1 or PD-L1. No investigational drug within 3 weeks before the first dose.
Biomarker or test result
pMMR/MSS tumour status

Main reasons for not taking part

  • Urgent need for surgery
  • Earlier treatment with CTLA-4, PD-1 or PD-L1 immune drugs
  • Autoimmune disease needing systemic treatment within 2 years
  • Major surgery within 4 weeks of the first dose
  • Active infection needing treatment

The registry criteria, word for word

Show all 14 criteriaShow less

Who can take part

  • ≥18 years of age at consent
  • Adenocarcinoma of the colon (rectosigmoid considered non-rectal); pMMR/MSS status
  • Any T3 or T4, N any, M0; disease amenable to surgical resection
  • ECOG Performance Status 0-1
  • Adequate tumor tissue sample with associated pathology report
  • Adequate hematologic, hepatic, and renal function
  • Reproductive status/contraception requirements per protocol

Who cannot take part

  • Investigational agent within 3 weeks of first dose
  • Imminent or urgent need for surgery
  • Prior treatment with ICIs targeting CTLA-4, PD-1, or PD-L1
  • Systemic corticosteroid/immunosuppressive therapy within 1 week of first dose (exceptions apply)
  • History of severe hypersensitivity to a fully human mAb; interstitial lung disease; pneumonitis requiring corticosteroids
  • Active or history of autoimmune disease requiring systemic treatment within 2 years
  • Major surgery within 4 weeks of first dose; active infection requiring treatment

Where in United Kingdom

Also in 5 other countries, 23 sites

  • AberdeenHospital not named in the registryContact: Medical MonitorNot yet recruiting
  • CardiffHospital not named in the registryContact: Medical MonitorNot yet recruiting
  • GlasgowHospital not named in the registryContact: Medical MonitorNot yet recruiting
  • LeedsHospital not named in the registryContact: Medical MonitorNot yet recruiting
  • LondonHospital not named in the registryContact: Medical MonitorNot yet recruiting

About the trial

What the trial wants to find out

The goal of this clinical trial is to learn if giving two medicines together, porustobart and pembrolizumab, before surgery can treat a common type of colon cancer called microsatellite stable (MSS) colon cancer in adults. This type of cancer can be removed with surgery and has not spread to other parts of the body. Both medicines work by helping the immune system fight cancer.

Read full original descriptionShow less

The main questions this study wants to answer:

How well do the medicines destroy the cancer before surgery? What side effects do participants have when taking the medicines?

Researchers will compare two groups to see which treatment schedule works better and is safer. Both groups get pembrolizumab. One group gets one dose of porustobart (Day 1 only), and the other group gets two doses (Day 1 and Day 22).

Participants will:

Complete certain tests and procedures to make sure they are eligible Get the medicines through a vein on Day 1 and Day 22 then have surgery 6-9 weeks after starting treatment Return for checkups and tests every 6 months for up to 3 years after surgery

The 2 groups in the trial

  • Dose Schedule 1 - Porustobart + PembrolizumabTreatment being tested

    Pembrolizumab IV every 3 weeks x 2 doses (Day 1, Day 22) plus porustobart x 1 dose (Day 1 only)

    Treatment: Pembrolizumab and Porustobart

  • Dose Schedule 2 - Porustobart + PembrolizumabTreatment being tested

    Pembrolizumab IV every 3 weeks x 2 doses (Day 1, Day 22) plus porustobart every 3 weeks x 2 doses (Day 1, Day 22)

    Treatment: Pembrolizumab and Porustobart

Questions to ask the study team

  1. How often do I need to come in, and for how long each time?
  2. Are travel costs paid?
  3. Can I keep my own doctor?
  4. What happens if I want to stop?

Contact the study team: see the registry record → Contacts and Locations

Print a page for my doctor

Data and sources

Registry record
Listed on ClinicalTrials.gov and on the EU's official list of trials (CTIS).
Official title
A Phase 2, Open-Label, Multicenter, Randomized Trial Evaluating the Efficacy and Safety of Different Schedules of Neoadjuvant Pembrolizumab and Porustobart in Patients With Resectable pMMR/MSS Colon Cancer
Plain-language title
Pembrolizumab and porustobart before surgery for colon cancer that can be removedGenerated from the registry record. The registry title is the official one.
AI summary
From the trial's eligibility criteria. Read by machine on 13 November 2026.
Record updated
12 November 2026