Clinical trial Recruiting at 1 site Phase 1 Interventional Ages 18 and up

BT-001 plus pembrolizumab for localized pMMR rectal cancer

Official title: A Phase I Study of the Safety and Efficacy of a Modified Vaccinia Virus (BT-001) Delivered by Endoscopic Intra-tumoural Injection Followed by Systemic Antiprogammed Death-1 (Anti-PD-1) Antibodies in Patients With Localised Rectal Cancer With Proficient Mismatch Repair (pMMR)

Run by Bispebjerg Hospital · NCT07687875 · Data updated 2026-11-12

This early-phase trial tests whether adding the oncolytic virus BT-001 to pembrolizumab is safe and tolerable for adults with localized pMMR rectal cancer prior to definitive surgery.

More Rectal Cancer Patients trials

Quick facts

PhasePhase 1
Study typeInterventional
Ages18 Years and up
SexAll
Enrollment20 (estimated)
SponsorBispebjerg Hospital
Academic / other
Drugs / interventionspembrolizumab, immunotherapy, prednisone
Locations1 site (Copenhagen, Captial Region)
StatusRecruiting
StartedOctober 23, 2026
Main results expectedDecember 31, 2028
Study endsDecember 31, 2033
Registry record updatedNovember 4, 2026
Trial IDNCT07687875 on ClinicalTrials.gov

Is this trial a fit for you?

Likely a good fit

Adults with localized pMMR rectal adenocarcinoma (stages cT2N0M0 to cT3bN2M0) eligible for potentially curative resection and without contraindications to pembrolizumab.

Probably not a fit

Patients with non-pMMR status, more advanced disease requiring non-curative approaches, or those who do not tolerate immunotherapy may not benefit.

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

In this Phase 1 study, patients with localized pMMR rectal cancer will receive BT-001 followed by the PD-1 blocker pembrolizumab to assess safety and tolerability of the combination. Eligibility requires appropriate surgical candidacy, confirmed pMMR status, and fit overall health, with specific blood and organ function criteria. The trial aims to see if the viral therapy can modulate the tumor environment to potentially enhance immunotherapy efficacy. No neoadjuvant therapy is required, and treatment precedes or accompanies planned curative resection as clinically indicated. Outcomes will focus on safety signals, tolerability, and preliminary activity to inform future studies.

Why it matters

Potential benefit: If successful, patients may experience improved response to immunotherapy and a smoother path to curative surgery.

How similar studies have gone: Early trials in select cancers suggest combining oncolytic virotherapy with checkpoint inhibitors can be safe and show signals of activity, but this specific combination in localized pMMR rectal cancer is novel.

Who can join: the full rules

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Histological diagnosis of primary, localised rectal adenocarcinoma (cT2N0M0 to cT3bN2M0, TNM classification version 8
* Diagnosis of Proficient Mismatch Repair (pMMR) rectal adenocarcinoma (using biopsy from the initial diagnostic endoscopy)
* Suitable for potentially curative surgical resection
* No contraindications for treatment with pembrolizumab
* Not requiring neoadjuvant therapy
* Aged \> 18 years at the time of inclusion
* Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1
* Have baseline laboratory results as follows:

  * Absolute neutrophil count (ANC) ≥ 1.0 x 109/L
  * Platelets ≥ 100 ×109/L (without platelet transfusion)
  * Haemoglobin ≥ 6.2 mmol/L or 10.0 g/dL (with or without red blood cell (RBC) transfusion)
  * Serum creatinine ≤ 1.5 × upper limit of normal (ULN)
  * Bilirubin \< 1.5 × ULN (or \< 2.5 x ULN in patients with Gilbert's syndrome)
  * ALT, AST and alkaline phosphatase \< 3 × ULN
* Provide written informed consent in accordance with all applicable regulations and follow the study procedures. Subjects must be capable of understanding the investigational nature, potential risks, and benefits of the study.

Exclusion Criteria:

* Have impending bowel obstruction or other indications for acute surgical intervention
* Have had concurrent immunotherapy in the 3 months before the start of the study therapy.
* Have acute or chronic hepatitis B or hepatitis C infection
* Evidence of immunosuppression for any reason:

  * Known HIV disease
  * Chronic oral or systemic steroid medication use at a dose of \> 10 mg/day of prednisolone or equivalent
  * Other signs or symptoms of clinical immune system suppression
* Have an autoimmune disorder (except thyroiditis with replacement therapy and type I diabetes mellitus)
* Have a condition requiring systemic treatment with either corticosteroids (\> 10 mg daily prednisone equivalents) or other immunosuppressive medications within 14 days of study drug administration. Inhaled or topical steroids and adrenal replacement doses \> 10 mg daily prednisone equivalents are permitted in the absence of active autoimmune disease
* Ongoing antiviral therapy active on vaccinia virus, e.g., ribavirin, cidofovir, interferon/ pegylated interferon
* History of severe exfoliative skin conditions (e.g., eczema or atopic dermatitis) requiring systemic therapy for more than 4 weeks within 2 years prior to BT-001 initiation
* Live virus vaccination within 28 days of BT-001 administration
* A history of hypersensitivity to egg or to any excipient of BT-001
* Pregnant or breast-feeding female. Confirmation that women of childbearing potential are not pregnant with a negative serum β-human chorionic gonadotrophin (β-hCG) pregnancy test results must be obtained within 7 days prior to the 1st administration of BT-001
* Fertile males and females who are unwilling to employ highly effective means of contraception during study treatment and for 4 months after the last dose of study treatment

Where it's running

  • Copenhagen University Hospital - Bispebjerg and Frederiksberg
    Copenhagen, Captial Region, Denmark
    Recruiting

Study contacts

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

How to take part

  1. Review the eligibility criteria above with your treating physician.
  2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
  3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.
Last reviewed 2026-11-14 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.