Camrelizumab with long-course chemoradiotherapy before surgery for locally advanced low rectal cancer (pMMR/MSS)

A Single-arm Phase II Clinical Study of Camrelizumab Combined With Long-course Chemoradiotherapy for Total Neoadjuvant Therapy in Locally Advanced Low pMMR/MSS Rectal Cancer

This trial tests whether giving camrelizumab before and after long-course chemoradiotherapy helps people with locally advanced, pMMR/MSS low rectal cancer achieve a higher complete response and preserve the rectum.

Quick facts

• Phase: PHASE2
• Study type: Interventional
• Enrollment: 44 (estimated)
• Ages: 18 Years to 75 Years
• Sex: All
• Sponsor: Chinese PLA General Hospital (other)
• Drugs / interventions: camrelizumab, chemotherapy, immunotherapy, prednisone
• Locations: 1 site (Beijing, Beijing Municipality)
• Trial ID: NCT07527026 on ClinicalTrials.gov

What this trial studies

This single-arm Phase II trial delivers camrelizumab combined with a long-course chemoradiotherapy program as total neoadjuvant therapy, using an induction chemo-immunotherapy phase, followed by long-course radiotherapy with concurrent chemotherapy, and then a consolidation chemo-immunotherapy phase prior to planned surgery. Eligible adults have histologically confirmed T3-4 and/or N+ low rectal adenocarcinoma (tumor margin ≤10 cm from the anal verge), are pMMR/MSS, ECOG 0-1, and have not received prior anti-tumor treatment. The primary goal is to increase clinical and pathological complete response rates to enable organ-preserving approaches where possible, with surgery scheduled after neoadjuvant therapy. The trial is run at Chinese PLA General Hospital in Beijing and follows participants through treatment, response assessment, and subsequent surgery.

Who should consider this trial

Good fit: Ideal candidates are adults 18–75 with pMMR/MSS, T3-4 and/or N+ low rectal adenocarcinoma (tumor ≤10 cm from the anal verge), ECOG 0–1, adequate organ function, and no prior anti-tumor therapy.

Not a fit: Patients with metastatic disease, prior rectal cancer treatments, poor performance status or organ dysfunction, or those with dMMR/MSI‑H tumors are unlikely to benefit from this protocol.

Why it matters

Potential benefit: If successful, this approach could raise complete response rates and allow more patients to avoid radical surgery and preserve their rectum.

How similar studies have performed: Combining PD‑1 inhibitors with chemoradiation has shown promising signals in early-phase trials but results in pMMR/MSS rectal cancer are still limited and the approach remains exploratory.

Eligibility criteria

Inclusion Criteria:

* Aged 18-75 years, male or female;

Histologically confirmed T3-4 and/or N+ rectal adenocarcinoma (AJCC/UICC TNM staging, 8th edition);

Lower margin of the tumor ≤10 cm from the anal verge;

Expected to achieve R0 resection;

Eastern Cooperative Oncology Group (ECOG) performance status 0-1;

Able to swallow tablets normally;

No prior anti-tumor therapy for rectal cancer, including radiotherapy, chemotherapy, surgery, etc.;

Planned to undergo surgical treatment after neoadjuvant therapy;

No contraindications to surgery;

Laboratory tests must meet the following requirements: white blood cell count (WBC) ≥4×10⁹/L; absolute neutrophil count (ANC) ≥1.5×10⁹/L; platelet count ≥100×10⁹/L; hemoglobin ≥90 g/L; serum total bilirubin ≤1.5× upper limit of normal (ULN); serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤2.5× ULN; serum creatinine ≤1.5× ULN or creatinine clearance ≥50 mL/min; international normalized ratio (INR) ≤1.5× ULN; activated partial thromboplastin time (APTT) ≤1.5× ULN;

Fertile male or female patients willing to use contraceptive measures during the trial.

Exclusion Criteria:

* Prior or current receipt of any anti-tumor therapy for cancer, including surgery, radiotherapy, chemotherapy, targeted therapy, immunotherapy, etc.

Known genetic testing showing MSI-H (microsatellite instability-high) or immunohistochemistry showing dMMR (deficient mismatch repair).

Major surgery or severe trauma within 4 weeks prior to the first dose of study drug.

Known allergy, hypersensitivity, or contraindication to any component of camrelizumab or platinum-based agents.

Presence of poorly controlled cardiac clinical symptoms or diseases, including but not limited to: (1) heart failure ≥ NYHA class II; (2) unstable angina; (3) myocardial infarction within 1 year; (4) clinically significant supraventricular or ventricular arrhythmias that have not been clinically intervened or remain poorly controlled after intervention.

Severe infection (CTCAE grade \>2) within 4 weeks prior to the first dose of study drug, such as severe pneumonia requiring hospitalization, bacteremia, infectious complications, etc.; baseline chest imaging indicating active pulmonary inflammation; presence of signs or symptoms of infection within 14 days prior to the first dose of study drug, or requiring oral or intravenous antibiotic therapy (excluding prophylactic antibiotic use).

Presence of any active autoimmune disease or history of autoimmune disease (e.g., interstitial pneumonia, uveitis, enteritis, hepatitis, hypophysitis, vasculitis, myocarditis, nephritis, hyperthyroidism, hypothyroidism \[excluding patients with stable hormone levels after treatment\]; patients with childhood asthma that has completely resolved and requires no intervention in adulthood, or vitiligo, may be included; subjects requiring bronchodilators for medical intervention are not eligible).

Congenital or acquired immunodeficiency, such as HIV infection, active hepatitis B (HBV DNA ≥500 IU/mL), hepatitis C (positive HCV antibody with HCV-RNA above the lower limit of detection of the assay), or co-infection with hepatitis B and C.

Use of immunosuppressive drugs within 14 days prior to the first dose of study drug, excluding nasal and inhaled corticosteroids or physiological doses of systemic corticosteroids (i.e., no more than 10 mg/day prednisone or equivalent physiological dose of other corticosteroids).

Known interstitial lung disease, except for interstitial changes detected only on imaging.

Diagnosis of another malignancy within 5 years prior to the first dose of study drug, except for malignancies with a low risk of metastasis or death (5-year survival rate \>90%), such as adequately treated basal cell carcinoma of the skin, squamous cell carcinoma of the skin, or cervical carcinoma in situ, which may be considered for enrollment.

Pregnant or breastfeeding women.

Any other factors deemed by the investigator that may lead to premature termination of the study, such as other serious diseases (including psychiatric disorders) requiring concomitant treatment, alcoholism, drug abuse, family or social factors, or factors that may affect subject safety or compliance.

Where this trial is running

Beijing, Beijing Municipality

• Chinese PLA General Hospital — Beijing, Beijing Municipality, China (RECRUITING)

Study contacts

• Principal investigator: Guanghai Dai, MD — Chinese PLA General Hospital
• Study coordinator: Guanghai Dai, MD

Conditions: Locally Advanced Rectal Cancer