Neoadjuvant PD-1 Blockade Toripalimab With or Without Celecoxib in Mismatch-repair Deficient or Microsatellite Instability-high Locally Advanced Colorectal Cancer (PICC): a Parallel-group, Randomized, Multi-cohort, Phase 2 Trial
Colorectal cancer of Mismatch Repair-deficient (dMMR)/ Microsatellite Instability-high (MSI-H) accounts for approximately 15% of all colorectal cancer patients, with a higher proportion in right colon cancer. Previous studies have found that colon cancer patients with dMMR/MSI-H cannot benefit from 5-fluorouracil (5-FU) adjuvant chemotherapy. Once patients have distant metastases, they are not sensitive to traditional palliative chemotherapy, and the prognosis is significantly worse than that of mismatch repair-proficient (pMMR)/microsatellite stability (MSS). A phase II clinical study of anti-PD-1 immunotherapy based on mismatch repair (MMR) status published in 《N Engl J Med》 showed that the objective response rate (ORR) of advanced colorectal cancer patients with dMMR received anti-PD-1 is 40%, and a longer response time can be obtained compared to conventional chemotherapy. Anti-PD-1 neoadjuvant therapy has proven to be safe and feasible in lung cancer, bladder cancer and malignant melanoma, and can achieve more than 40% of major pathological response. However, there are no reports of anti-PD-1 neoadjuvant therapy for the dMMR/MSI-H colorectal cancer. Therefore, the aim of this study was to find the best multidisciplinary treatment for resectable colorectal cancer patient with the dMMR/MSI-H phenotype and to explore whether cyclooxygenase (COX) inhibitors combined with anti-PD-1 monoclonal antibody (mAb) could further improve efficacy.
• Willing and able to provide written informed consent.
• Histological or cytological documentation of adenocarcinoma of the colon or rectum.
• Tumor tissues were identified as mismatch repair-deficient (dMMR) by immunohistochemistry (IHC) method or microsatellite instability-high (MSI-H) by polymerase chain reaction (PCR).
• Male or female subjects ≧ 18 years of age.
• Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1.
• Determined CT or MRI scans (done within 14 days of registration) of the chest, abdomen and pelvis: locally advanced (cT3-4 or cN1-2 \[with the definition of a clinically positive lymph node being any node ≥ 1.0 cm\]).
• Non complicated primary tumor (obstruction, perforation, bleeding).
• No previous any systemic anticancer therapy for colorectal cancer disease.
• Adequate bone marrow, hepatic and renal function as assessed by the following laboratory requirements conducted within 7 days of starting study treatment.