KORTUC (KRC-01) Plus Radiotherapy for Organ Preservation in Rectal Cancer

NCT07622017 | Not Yet Recruiting Phase 2

• 2 other identifiers: 2025-524378-40-00CSET number 2025/4237
• Study Type: interventional
• Target: 24
• Locations: 1 country
• Sites: 2

Brief Summary

This phase II clinical trial is evaluating whether adding KRC-01 injections to standard chemoradiotherapy may improve treatment outcomes in patients with locally advanced rectal cancer without metastases. KRC-01 is an investigational product designed to improve the effectiveness of radiotherapy by increasing oxygen levels inside tumors, which may help radiation work better. KRC-01 contains hydrogen peroxide and sodium hyaluronate and is injected directly into the tumor before radiotherapy sessions. Previous clinical experience in Japan, including studies in several types of cancer, suggested that this approach may improve tumor oxygenation and enhance the effect of radiotherapy. The main objective of the K-BOOST study is to evaluate how many patients achieve a complete clinical response after treatment with chemoradiotherapy combined with intratumoral KRC-01 injections, potentially allowing some patients to avoid surgery. Surgery may still be recommended depending on the individual response to treatment. Approximately 24 patients will participate in this multicenter French study. The experimental treatment period lasts approximately 26 weeks, and participants will be followed for up to 2 years.

Conditions

Rectal Cancer

Keywords

Intratumoral; chemoradiotherapy; advanced rectal cancer; Organ Preservation

Outcome Measures

Primary Outcomes (1)

• Clinical Complete Response (cCR) Rate at Week 24

  Clinical complete response (cCR) rate is defined as the proportion of patients with no clinical, rectoscopic, or radiographic evidence of disease at Week 24 after treatment. Patients with at least one missing clinical, rectoscopic, or radiographic evaluation, or lost to follow-up before Week 25, will be considered non-responders.

  Week 24

Secondary Outcomes (4)

• Pathological Complete Response (pCR) Rate

  At time of surgery (approximately Week 26)

• Progression-Free Survival (PFS)

  Up to 24 months

• Overall Survival (OS)

  Up to 24 months

• Incidence of Adverse Events

  From first study treatment administration up to 24 months

Study Arms (1)

Intratumoral KRC-01 injections combined with standard chemoradiotherapy

EXPERIMENTAL

Participants receive intratumoral KRC-01 injections (8 injections) combined with standard long-course chemoradiotherapy (radiotherapy: 50 Gy in 25 fractions plus capecitabine 825 mg/m² orally twice daily for 5 weeks) and consolidation chemotherapy with CAPOX or FOLFOX according to investigator decision and institutional practice. Surgery with total mesorectal excision (TME) may be performed depending on tumor response and multidisciplinary team assessment.

Drug: KRC-01 (KORTUC); Radiation: Radiotherapy; Drug: Capecitabine; Drug: CAPOX; Drug: FOLFOX; Procedure: Optionnal TME

Interventions

KRC-01 (KORTUC) DRUG

Intratumoral injections administered before radiotherapy.

Intratumoral KRC-01 injections combined with standard chemoradiotherapy

Radiotherapy RADIATION

Standard radiotherapy administered with chemotherapy.

Intratumoral KRC-01 injections combined with standard chemoradiotherapy

Capecitabine DRUG

Standard chemotherapy regimen (capecitabine) administered with radiotherapy.

Intratumoral KRC-01 injections combined with standard chemoradiotherapy

CAPOX DRUG

Standard chemotherapy regimen (capecitabine and oxaliplatin), after chemoradiotherapy

Intratumoral KRC-01 injections combined with standard chemoradiotherapy

FOLFOX DRUG

Standard chemotherapy regimen (5-fluorouracil, leucovorin, and oxaliplatin), after chemoradiotherapy

Intratumoral KRC-01 injections combined with standard chemoradiotherapy

Optionnal TME PROCEDURE

Surgery with total mesorectal excision (TME) may be performed depending on tumor response and multidisciplinary team assessment

Intratumoral KRC-01 injections combined with standard chemoradiotherapy

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Males and females ≥ 18 years of age.
• Eastern Cooperative Oncology Group (ECOG) performance status 0 or 1.
• Histopathologically confirmed locally advanced rectal adenocarcinoma, stage III (high risk)
• No evidence of metastatic disease on computed tomography (chest and abdomen), including resectable metastases. (M0, and no oligometastases)
• At least one of the following criteria: cT4a, cT4b, presence of extramural invasion (EMVI+), cN2, involvement of the mesorectal fascia (MFI+), involvement of lateral lymph nodes (lat LN+)
• Adenocarcinoma located with a lower border less than 15 cm from the anal margin
• Primary resection without chemoradiotherapy is unlikely to achieve clear margins.
• Tumor lesion must be mesurable by endoscopic visual assessment
• Target tumor is accessible for intratumoral injections.
• Intention to undergo treatment including 5 Fu based chemoradiotherapy and CAPOX (6 cycles) or FOLFOX (9 cycles)
• Life expectancy \> 6 months
• Acceptable organ functions, as evidenced by the following laboratory data:
• Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤2.0×upper limit of normal (ULN).
• Total serum bilirubin ≤ 1.5×ULN.
• Absolute neutrophil count (ANC): ≥ 1500 cells/mm³.

You may not qualify if:

• Patients not deemed fit for radiotherapy or preexisting condition which would deter radiotherapy, e.g., fistulas, severe ulcerative colitis (including subjects currently taking sulphasalazine), active Crohn's disease, prior adhesions.
• Any Previous radiotherapy in the pelvic region.
• Contraindications to MRI (e.g., subjects with pacemakers, claustrophobia, excessive weight, etc.).
• Participation in another clinical study with an investigational product during the last 3 months.
• Prior rectal surgery.
• Prior investigational treatment for rectal cancer.
• Patients with known high microsatellite instability (MSI-H) or mismatch repair deficient (dMMR) tumors are not eligible, as these patients may benefit from standard-of-care immunotherapy.
• High medical risk because of systemic diseases (e.g., uncontrolled infections, uncontrolled diabetes) in addition to the qualifying disease under study. Patients must not have any uncontrolled concurrent illness including, but not limited to, severe active or uncontrolled infection, symptomatic congestive heart failure, unstable, angina pectoris, cardiac arrhythmia, uncontrolled diabetes mellitus or psychiatric illness/social situations that would limit compliance with study requirements.
• Patients receiving therapeutic anticoagulation are not eligible. Prophylactic anticoagulation at low dose (e.g., thromboprophylaxis) may be allowed at the investigator's discretion, provided that the bleeding risk is considered minimal.
• Patients receiving concomitant treatment with brivudine or who have received brivudine within the previous 4 weeks.
• Peripheral sensory neuropathy grade ≥2 (for the future administration of oxaliplatin)
• Concomitant medications/comorbidities that may prevent the patient from receiving study treatments,
• Contraindication to fluoropyrimidines or oxaliplatin and capecitabin as mentioned in the SMPC of investigational medicinal products: FOLFOX is contraindicated in patients with known hypersensitivity to 5-fluorouracil, oxaliplatin, leucovorin, or other platinum compounds; in those with severe renal impairment (CrCl \<30 mL/min), significant bone marrow suppression, uncontrolled infections, or pre-existing grade ≥2 peripheral neuropathy. It is also contraindicated in individuals with complete or partial dihydropyrimidine dehydrogenase (DPD) deficiency due to the risk of severe 5-FU toxicity, as well as in cases of severe hepatic dysfunction, pregnancy, and breastfeeding. Caution is advised in patients with poor performance status (ECOG ≥3).
• Yellow fever vaccine and live attenuated vaccines are contraindicated due to the risk of severe vaccine-induced infection. Note: The currently authorized COVID-19 vaccines are not live vaccines and therefore can be safely administered.
• Known history of human immunodeficiency virus (HIV) infection or seropositive results consistent with active hepatitis B virus (HBV) or active hepatitis C virus (HCV) infection.

Sponsors & Collaborators

• Kortuc, Inc.: collaborator
• Gustave Roussy, Cancer Campus, Grand Paris: lead

Study Sites (2)

Gustave Roussy

Villejuif, Val de Marne, 94800, France

Location

Institut Bergonié

Bordeaux, 33000, France

Location

MeSH Terms

Conditions

Rectal Neoplasms

Interventions

Radiotherapy; Capecitabine; Folfox protocol

Condition Hierarchy (Ancestors)

Colorectal Neoplasms; Intestinal Neoplasms; Gastrointestinal Neoplasms; Digestive System Neoplasms; Neoplasms by Site; Neoplasms; Digestive System Diseases; Gastrointestinal Diseases; Intestinal Diseases; Rectal Diseases

Intervention Hierarchy (Ancestors)

Therapeutics; Deoxycytidine; Cytidine; Pyrimidine Nucleosides; Pyrimidines; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Fluorouracil; Uracil; Pyrimidinones; Deoxyribonucleosides; Nucleosides; Nucleic Acids, Nucleotides, and Nucleosides

Central Study Contacts

Eric Deutsch, MD, PhD

CONTACT

(+33)142116573; Eric.DEUTSCH@gustaveroussy.fr

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: May 27, 2026
• First Posted: June 2, 2026
• Study Start (Estimated): July 1, 2026
• Primary Completion (Estimated): January 1, 2029
• Study Completion (Estimated): July 1, 2030
• Last Updated: June 2, 2026

Record last verified: 2026-05

Data Sharing

• IPD Sharing: Will not share

Locations

FR (2)