NEOPRISM-CRC : Neoadjuvant Pembrolizumab Stratified to Tumour Mutation Burden for High Risk Stage 2 or Stage 3 MMR-deficient Colorectal Cancer
Colorectal cancer (CRC) is the 2nd to 3rd most common malignant disease in developed countries, with over 1 million new cases and 500,000 deaths worldwide each year. The primary treatment for early stage CRC is surgery to remove the tumour, which is possible in 80% of patients. Even after surgery up to half of patients will develop recurrence or spread of the disease (metastases) which is incurable. Survival after 5 years is approximately 14% for patients with metastatic disease. Clinical trials using immunotherapy drugs called 'immune checkpoint inhibitors' have shown excellent results in advanced colorectal cancer patients who have certain genetic characteristics called 'mismatch repair deficiency (MMR-d)' and 'high microsatellite instability (MSI-h)'. The benefits of immunotherapy as a treatment prior to surgery to remove the tumour (neoadjuvant treatment) has been observed in both melanoma and in glioblastoma with enhanced local and systemic anti-tumour responses. Pembrolizumab is an immunotherapy drug and works by helping the body's own immune system to fight the cancer cells. The NEOPRISM-CRC trial will investigate whether giving pembrolizumab before surgery is safe, whether it improves the chances of the tumour being removed completely and whether it delays or prevents the cancer from coming back. Pembrolizumab treatment lasts for a maximum of 9 weeks (maximum of 3 cycles of treatment, each cycle consisting of 3 weeks) and is given prior to surgery. Following surgery patients will be followed up for at least 3 years after their surgery and to a maximum of 5 years. Target recruitment is 78 patients and recruitment is expected to take place over a 42 month period. Blood, tissue, mouth swabs and stool samples will be collected from patients throughout the trial to better understand the biology of immunotherapy as a treatment for CRC prior to surgery.
• Histologically proven adenocarcinoma of the colon or rectum which is MMR-d by IHC or MSI-H by PCR (or microsatellite testing if routine practice).
• Patient is fit (ECOG 0-1) and eligible for planned curative surgery in keeping with NICE guidelines and considered fit/suitable for adjuvant chemotherapy as per local site investigator's discretion based on:
∙ Radiological node positive T1-4 CRC or
‣ Node negative high risk T3 defined as EITHER ≥ 5mm of extramural depth of invasion OR unequivocal EMVI on imaging (regardless of depth) or Node negative T4 disease
• Patients with rectal cancer are eligible if it is determined that neoadjuvant chemo-radiotherapy is not required to achieve a R0 resection.
• Patients presenting with acute colonic obstruction may enter the trial only after obstruction is relieved by a successful defunctioning stoma/stent, and when recovered to a fitness level consistent with the other eligibility criteria
• Adequate bone marrow function:
‣ White Blood Cell \>3.0 x 10\^9/L;
⁃ Absolute neutrophil count ≥1.5 x 10\^9/L
⁃ Platelets ≥100 x 10\^9/L.
⁃ Haemoglobin ≥90 g/L
• Adequate renal function:
• GFR \>50 mL/min estimated using validated creatinine clearance calculation (e.g. Cockroft-Gault) NB If the calculated creatinine clearance is \< 50 mL/min, a formal 24 hour urine collection or isotope clearance must be carried out demonstrating GFR ≥ 50 mL/min as per institutional standards
• Adequate liver function:
• Total bilirubin \< 1.5 times Upper Limit of Normal (ULN) OR direct bilirubin ≤ULN for participants with total bilirubin levels \>1.5 × ULN
• AST and ALT ≤ 2.5 × ULN
• Adequate coagulation:
• International normalized ratio (INR) OR prothrombin time (PT) and Activated partial thromboplastin time (aPTT) ≤1.5 × ULN unless participant is receiving anticoagulant therapy as long as PT or aPTT is within therapeutic range of intended use of anticoagulants
• Aged ≥18 years
⁃ Able and willing to provide written informed consent
⁃ Female patients of child bearing potential must be willing to use highly effective contraception for the duration of trial treatment and for 120 days after last dose of pembrolizumab