Clinical trial Recruiting at 1 site Phase 2 Interventional Ages 18 and up

Adding tislelizumab with or without the probiotic Probio-M9 to pre-surgery chemoradiation for pMMR/MSS locally advanced rectal cancer.

Official title: Neoadjuvant Chemoradiotherapy Combined With Tislelizumab With or Without Probio-M9 in pMMR/MSS Locally Advanced Middle and Low Rectal Cancer: A Single-Center, Prospective, Randomized Controlled Trial (NCRIT-PM9 Trial)

Run by Seventh Medical Center of PLA General Hospital · NCT07458529 · Data updated 2026-11-12

This will see if adding the PD-1 drug tislelizumab, with or without the probiotic Probio-M9, to standard pre-surgery chemoradiation helps adults with pMMR/MSS locally advanced rectal cancer.

Quick facts

PhasePhase 2
Study typeInterventional
Ages18 Years and up
SexAll
Enrollment50 (estimated)
SponsorSeventh Medical Center of PLA General Hospital
Academic / other
Drugs / interventionschemotherapy, immunotherapy, Tislelizumab
Locations1 site (Beijing, Beijing Municipality)
StatusRecruiting
StartedFebruary 10, 2026
Main results expectedMay 5, 2027
Study endsDecember 1, 2030
Registry record updatedMarch 10, 2026
Trial IDNCT07458529 on ClinicalTrials.gov

Is this trial a fit for you?

Likely a good fit

Adults (≥18) with biopsy‑proven, non‑metastatic stage II–III pMMR/MSS rectal adenocarcinoma within 10 cm of the anal verge, ECOG 0–2, measurable tumor, and no prior anti‑tumor therapy are the intended participants.

Probably not a fit

Patients with distant metastases, MSI‑high tumors, significant organ dysfunction, autoimmune/immune disorders, prior cancer treatment, or inability to undergo surgery are unlikely to qualify or benefit.

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

What this trial studies

Adults with clinically staged II–III pMMR/MSS rectal adenocarcinoma receive long-course chemoradiation with concurrent capecitabine, followed by two cycles of CapeOX chemotherapy and intravenous tislelizumab. Participants are randomized to daily oral Probio-M9 or matched placebo from treatment start until surgery, and all undergo total mesorectal excision (TME). The trial compares the two combination arms to a control arm receiving chemoradiation alone, monitoring safety, imaging and pathological response, and surgical outcomes. Outcomes will use RECIST/MRI and pathology to measure tumor shrinkage and treatment-related adverse events.

Why it matters

Potential benefit: If successful, the regimen could increase tumor response before surgery and may reduce the chance of recurrence.

How similar studies have gone: Combining immunotherapy with chemoradiation has shown promise mainly in MSI‑high rectal cancer and early-phase work, but using tislelizumab in pMMR/MSS disease and adding Probio-M9 is largely experimental.

Who can join: the full rules

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Age ≥ 18 years
* ECOG performance status 0-2
* Biopsy-proven rectal adenocarcinoma
* Distal tumor margin within 10 cm of the anal verge
* No distant metastasis
* Clinical stage II or III based on MRI (T4b excluded)
* Maximum diameter of rectal tumor ≥ 10 mm on baseline CT or MRI (measurable lesion according to RECIST 1.1)
* Willing and able to comply with the study protocol
* Willing to provide blood and tissue specimens for research purposes
* No prior anti-tumor treatment (e.g., radiotherapy, chemotherapy, immunotherapy, biological therapy, or herbal therapy)
* No history of immune system disorders (e.g., systemic lupus erythematosus, rheumatoid arthritis, systemic vasculitis, scleroderma, pemphigus, dermatomyositis, mixed connective tissue disease, autoimmune hemolytic anemia, thyroid autoimmune disease, ulcerative colitis, HIV infection, etc.)
* No significant dysfunction of major organs (heart, lung, liver, kidney)
* No jaundice or gastrointestinal obstruction
* No acute or ongoing infection
* Adequate hematologic and biochemical function including:

  * Neutrophils ≥ 1.5 × 10\^9/L
  * Hemoglobin ≥ 80 g/L
  * Platelets ≥ 100 × 10\^9/L
  * Serum creatinine ≤ 1.5 × ULN
  * Total bilirubin ≤ 1.5 × ULN
  * ALT and AST ≤ 2.5 × ULN
* No social or psychiatric disorders that may interfere with study participation
* Women of childbearing potential must have a negative pregnancy test before enrollment and must use effective contraception from study entry until 60 days after the last dose of study drug

Exclusion Criteria:

* History of multiple primary cancers or concomitant malignant tumors other than rectal cancer
* Receipt of any anti-cancer treatment (e.g., surgery, chemotherapy, radiotherapy, or other systemic therapies) within the past 5 years
* History of recent major surgery
* Conditions that may affect the gastrointestinal absorption of capecitabine (e.g., inability to swallow, persistent nausea or vomiting, chronic diarrhea)
* Uncontrolled or severe concomitant diseases of any kind
* Known allergy or hypersensitivity to any components of the study drugs
* Estimated life expectancy ≤ 5 years due to any cause
* Planned or prior organ or bone marrow transplantation
* Use of immunosuppressive therapy or systemic corticosteroids for immunosuppressive purposes within 1 month prior to enrollment
* History of central nervous system disorders that may impair the ability to provide informed consent or affect compliance with oral medication (investigator discretion)
* Other conditions that may interfere with study results or lead to premature discontinuation of study treatment (e.g., alcoholism or drug abuse)
* Pregnant or breastfeeding women, or women planning to become pregnant during the treatment period

Where it's running

  • Seventh Medical Center of Chinese PLA General Hospital
    Beijing, Beijing Municipality, China
    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.