Ongoing Clinical Trials for Microsatellite Instability Cancer
There are currently 4 ongoing clinical trials investigating new treatments for microsatellite instability cancer. These studies are testing various immunotherapy combinations and targeted therapies across multiple European countries. The trials focus on patients with advanced or metastatic cancers that show either microsatellite instability-high (MSI-H) or mismatch repair deficiency (dMMR), including colorectal cancer, endometrial cancer, and other solid tumors. (Also known as: MSI-H cancer, dMMR cancer)
Clinical trial locations
- Belgium
- Study on the Safety and Effects of GSK4418959 and Dostarlimab for Adults with Colorectal Cancer with Mismatch Repair Deficiency or High Microsatellite Instability
- Study Comparing MK-1308A and Pembrolizumab for Patients with Advanced Colorectal Cancer with High Microsatellite Instability or Mismatch Repair Deficiency
- Denmark
- Estonia
- France
- Germany
- Greece
- Hungary
- Italy
- Lithuania
- Netherlands
- Study on the Safety and Effects of GSK4418959 and Dostarlimab for Adults with Colorectal Cancer with Mismatch Repair Deficiency or High Microsatellite Instability
- Study on PET Imaging with Fianlimab and Cemiplimab for Patients with Advanced Solid Tumors, with or without Platinum-Based Chemotherapy
- Study Comparing MK-1308A and Pembrolizumab for Patients with Advanced Colorectal Cancer with High Microsatellite Instability or Mismatch Repair Deficiency
- Poland
- Romania
- Spain
- Study on the Safety and Effects of GSK4418959 and Dostarlimab for Adults with Colorectal Cancer with Mismatch Repair Deficiency or High Microsatellite Instability
- Study Comparing MK-1308A and Pembrolizumab for Patients with Advanced Colorectal Cancer with High Microsatellite Instability or Mismatch Repair Deficiency
Study on the Safety and Effects of GSK4418959 and Dostarlimab for Adults with Colorectal Cancer with Mismatch Repair Deficiency or High Microsatellite Instability
This trial is testing a new medication called GSK4418959, which works by inhibiting a protein that cancer cells use to repair their DNA. The study has three parts: one determines the right dose of GSK4418959 alone, another tests its effectiveness against colorectal and endometrial cancers, and the third combines it with an immunotherapy called dostarlimab (also known as JEMPERLI).
Main inclusion criteria: You must be at least 18 years old with advanced cancer that shows mismatch repair deficiency or microsatellite instability-high characteristics. You should be fairly active (ECOG status 0-1) with at least 3 months life expectancy. For Part 2, you need to have colorectal or endometrial cancer and have received 1-3 previous treatments including at least one immunotherapy. Your cancer must be measurable on scans, and if possible, you should be willing to provide tumor tissue samples.
Main exclusion criteria: You cannot participate if you had major surgery within the past 4 weeks, have untreated brain metastases, significant heart problems, active infections requiring treatment, HIV, active hepatitis B or C, or if you are pregnant or breastfeeding. You also cannot join if you recently participated in another drug trial or are taking medications that significantly interfere with the study drug.
Trial focus: The study aims to find the safest and most effective dose of GSK4418959, both alone and in combination with immunotherapy. It will monitor how tumors respond to treatment through regular scans and biopsies, track side effects carefully, and measure how long patients benefit from the treatment.
Investigational drugs: GSK4418959 is taken as tablets by mouth and targets the Werner helicase enzyme that certain cancer cells need for survival. Dostarlimab is given through an intravenous infusion at 500 mg and helps the immune system recognize and attack cancer cells.
Study of Monalizumab and Volrustomig for Patients with MSI and/or dMMR Metastatic Cancer
This French trial is testing a combination of two immunotherapy medications, monalizumab and MEDI5752 (also called volrustomig), for patients with metastatic cancer that has spread to other parts of the body. The study will last up to 24 weeks with regular monitoring through MRI scans.
Main inclusion criteria: You must be at least 18 years old, weigh more than 35 kilograms, and have confirmed advanced or metastatic cancer that cannot be surgically removed. Your tumor must show mismatch repair deficiency or microsatellite instability characteristics. You need at least one measurable tumor visible on CT or MRI scans and should be willing to provide tumor tissue samples. You must have a performance status of 0 or 1, meaning you can carry out daily activities with minimal restrictions, and have at least 12 weeks life expectancy. Your heart function (QT interval) must be normal, and you need adequate blood counts and organ function. You must have tried at least one previous treatment that did not work or could not be tolerated, and be registered in a national health care system.
Main exclusion criteria: You cannot participate if you have a different type of cancer not being studied, are outside the specified age range, or belong to a vulnerable population requiring special protection.
Trial focus: The study evaluates how well these two immunotherapy medications work together to help the immune system fight cancer. Researchers will measure tumor response, monitor side effects, track progression-free survival (how long the cancer stays controlled), and assess overall survival.
Investigational drugs: Both monalizumab and MEDI5752 are given through intravenous infusion. Monalizumab blocks proteins that prevent the immune system from attacking cancer cells, while MEDI5752 is a bispecific antibody that targets two different immune checkpoint pathways simultaneously to boost the anti-cancer response.
Study on PET Imaging with Fianlimab and Cemiplimab for Patients with Advanced Solid Tumors, with or without Platinum-Based Chemotherapy
This Dutch trial focuses on using advanced PET imaging alongside treatment with cemiplimab, an immunotherapy medication. Some patients may also receive platinum-based chemotherapy. The study aims to find the best dose and timing for imaging while treating various advanced solid tumors including melanoma, lung cancer, cervical cancer, and others with microsatellite instability characteristics.
Main inclusion criteria: You must be at least 18 years old with confirmed locally advanced or metastatic solid cancer. You need at least one tumor that can be biopsied safely and at least one measurable lesion on scans. You should have an ECOG performance status of 0 or 1 and at least 12 weeks life expectancy. Your organ and bone marrow function must be adequate, including hemoglobin at least 9.0 g/dL, adequate white blood cell counts, platelet count at least 100 x 10⁹/L, proper kidney function, and adequate liver function. You must be willing to sign an informed consent form and follow all study procedures.
Main exclusion criteria: You cannot participate if you have metastatic cancer that cannot benefit from cemiplimab treatment or if you belong to a vulnerable population.
Trial focus: The study uses a special imaging tracer called 89Zr-DFO-REGN3767 to visualize how tumors respond to treatment. Researchers will determine the optimal dose and timing for PET imaging, monitor treatment effectiveness through regular scans, evaluate safety, and track tumor response using standardized criteria.
Investigational drugs: Cemiplimab is given as an intravenous infusion at 350 mg every three weeks. It is an immune checkpoint inhibitor that helps the immune system recognize and attack cancer cells. Platinum-based chemotherapy may be added depending on the cancer type. The imaging agent 89Zr-DFO-REGN3767 is used to help visualize treatment response through PET scans.
Study Comparing MK-1308A and Pembrolizumab for Patients with Advanced Colorectal Cancer with High Microsatellite Instability or Mismatch Repair Deficiency
This large international trial, spanning 13 European countries, compares several treatment approaches for Stage IV colorectal cancer with specific genetic characteristics. The study tests MK-1308A (a combination of quavonlimab and pembrolizumab), pembrolizumab alone, and other experimental combinations including MK-4280A, MK-7684A, and MK-4830 with pembrolizumab.
Main inclusion criteria: You must have confirmed Stage IV colorectal cancer with mismatch repair deficiency or microsatellite instability-high characteristics. Your cancer must be measurable by imaging, and you need at least 3 months life expectancy. You must provide a tumor tissue sample from either a previous biopsy within the last 5 years or a new one, and this tissue should not have been previously treated with radiation. Your organs must function well enough to tolerate treatment. Female participants must not be pregnant or breastfeeding and must use effective birth control during the study and for at least 120 days afterward. The study has two cohorts: Cohort A is for patients who have already received treatment for advanced disease and whose cancer has progressed, while Cohort B is for patients with untreated Stage IV disease.
Main exclusion criteria: The specific exclusion criteria focus on ensuring participants have the correct type of cancer with MSI-H or dMMR characteristics.
Trial focus: The study aims to compare how well different immunotherapy combinations work in shrinking tumors and improving patient outcomes. Researchers will measure how long the treatment response lasts, how long patients live without cancer progression, and overall survival rates. Safety will be closely monitored throughout the trial, with all side effects recorded and evaluated.
Investigational drugs: MK-1308A combines quavonlimab and pembrolizumab to help the immune system fight cancer. Pembrolizumab is also being tested alone. MK-4280A, MK-7684A, and MK-4830 are additional experimental therapies designed to enhance the immune system’s ability to target cancer cells. All treatments are administered through intravenous infusion.
Summary
The four ongoing clinical trials for microsatellite instability cancer represent diverse approaches to treating this condition across Europe. A notable concentration of trials is evident in the Netherlands, which hosts three of the four studies, while one trial spans an impressive 13 countries across Europe, demonstrating broad international collaboration.
The trials predominantly focus on immunotherapy combinations, with several studies testing established checkpoint inhibitors like pembrolizumab, cemiplimab, and dostarlimab alongside novel agents. Particularly innovative is the GSK4418959 study, which introduces a completely different mechanism targeting DNA repair through Werner helicase inhibition, representing a potentially groundbreaking approach for tumors with mismatch repair deficiency.
Colorectal cancer receives the most attention, featured prominently in three of the four trials, reflecting its common association with microsatellite instability. However, the studies also include other solid tumors such as endometrial cancer, melanoma, lung cancer, and cervical cancer, acknowledging that MSI-H/dMMR characteristics can appear across various cancer types.
An interesting trend is the emphasis on combination therapies rather than single-agent approaches, with most trials testing multiple treatment arms to identify optimal therapeutic strategies. The inclusion of both treatment-naive patients and those who have exhausted standard options ensures these studies address the full spectrum of patient needs in this disease area.
