Myriam Chalabi

Dr. Myriam Chalabi is a medical oncologist and translational researcher at the Netherlands Cancer Institute (Antoni van Leeuwenhoek Hospital) in Amsterdam, where she serves as Clinical Group Leader in Gastrointestinal Oncology. She is one of the most influential voices in the rapidly emerging field of neoadjuvant immunotherapy for gastrointestinal cancers, and the principal investigator of the landmark NICHE clinical trial program — a series of phase II studies examining neoadjuvant immune checkpoint blockade in both mismatch repair-deficient (dMMR) and mismatch repair-proficient (pMMR) colon cancer. Her findings from NICHE-2, published in the New England Journal of Medicine in 2024, demonstrated pathological complete responses in 68% of patients with locally advanced dMMR colon cancer treated with neoadjuvant nivolumab plus ipilimumab, fundamentally reshaping the treatment paradigm for this disease. Dr. Chalabi’s research program integrates rigorous clinical trial design with deep translational analyses of the tumor microenvironment, immune biomarkers, and treatment resistance, making her one of the leading scientists in cancer immunotherapy.

Current Positions

• Medical Oncologist and Clinical Group Leader, Gastrointestinal Oncology, Netherlands Cancer Institute / Antoni van Leeuwenhoek Hospital, Amsterdam, February 2016–present
• Principal Investigator, NICHE Trial Program (NCT03026140), Netherlands Cancer Institute
• Principal Investigator, NEOASIS Study (pan-cancer neoadjuvant botensilimab plus balstilimab), Netherlands Cancer Institute

Education

• MD, Universiteit Maastricht (University of Maastricht), 2002–2008

Professional Experience

• Resident, Internal Medicine, Atrium Medisch Centrum, August 2008–December 2013
• Medical Oncologist, Antoni van Leeuwenhoek / Netherlands Cancer Institute, January 2014–December 2015
• Medical Oncologist and Clinical Group Leader, Gastrointestinal Oncology, Netherlands Cancer Institute, February 2016–present

Research Activity

• Neoadjuvant immunotherapy in dMMR colon cancer: Principal investigator of the NICHE study program. NICHE-1 (phase II) established proof of concept for neoadjuvant nivolumab plus ipilimumab in both dMMR and pMMR colon cancer. NICHE-2 (New England Journal of Medicine, 2024), enrolling 115 patients with locally advanced dMMR colon cancer, reported a pathological complete response rate of 68% and major pathological response in 95% of evaluable patients, with no recurrences at a median follow-up of 26 months. NICHE-3 (Nature Medicine, 2024) investigated neoadjuvant nivolumab plus relatlimab (anti-LAG-3) in dMMR colon cancer, achieving pathological responses in 57 of 59 patients (97%) including 40 pathological complete responses (68%).
• Neoadjuvant immunotherapy in pMMR colon cancer: Led the pMMR arm of the NICHE study, publishing comprehensive clinical and translational results in Nature (2025). Among 31 pMMR patients treated with nivolumab plus ipilimumab, the response rate was 26%, with six major pathological responses. Identified chromosomal genomic instability and tumor proliferation signatures as potential biomarkers for response. Defined the landscape of tumor microenvironment features associated with resistance in pMMR tumors.
• Neoadjuvant immunotherapy in gastric and gastroesophageal junction cancer: Principal investigator of the phase II PANDA trial, combining atezolizumab with chemotherapy (docetaxel, oxaliplatin, capecitabine) for resectable gastric/GEJ adenocarcinoma; published in Nature Medicine (2024). Major pathological response was achieved in 70% of patients. Serial tissue sampling revealed distinct immunological effects of anti-PD-L1 monotherapy versus combination with chemotherapy on the tumor microenvironment.
  MATTERHORN trial: Investigator in this global phase III trial evaluating perioperative durvalumab plus FLOT in resectable gastric/GEJ adenocarcinoma (Journal of Clinical Oncology, 2025/2026), which demonstrated significant improvement in event-free survival.
• Neoadjuvant immunotherapy in rectal cancer: Principal investigator of the TARZAN study, evaluating short-course radiotherapy followed by atezolizumab and bevacizumab for organ preservation in rectal cancer; achieved 56% clinical complete/near-complete response rate in pMMR tumors.
  Pan-cancer neoadjuvant immunotherapy: Principal investigator of the NEOASIS study, an adaptive phase II pan-cancer trial evaluating neoadjuvant botensilimab (Fc-enhanced anti-CTLA-4) plus balstilimab (anti-PD-1) in early-stage dMMR and pMMR solid tumors including triple-negative breast cancer, ER+ breast cancer, Merkel cell carcinoma, sarcoma, and colorectal cancer; safety run-in results presented at AACR 2025.
• MSI-H/dMMR metastatic colorectal cancer: Contributing investigator in the CheckMate 8HW phase III trial (nivolumab plus ipilimumab versus nivolumab versus chemotherapy in MSI-H/dMMR mCRC), published in The Lancet (2025) and New England Journal of Medicine (2024). Co-investigator in the KEYSTEP-008 study evaluating pembrolizumab-based combinations in MSI-H/dMMR mCRC.
• Cancer immunotherapy biomarkers: Translational research on immune biomarkers for response and resistance to immune checkpoint blockade including the role of B2M defects and γδ T cells in MMR-d cancers (Nature, 2023); innate immune landscape as predictor of nivolumab efficacy in dMMR/MSI tumors (Drug Rediscovery Protocol, Clinical Cancer Research, 2024);
• Immunoscore biopsy validation for rectal cancer watch-and-wait strategy (Journal of Clinical Oncology, 2023).
• Review leadership: First author of a landmark review on the rapidly evolving paradigm of neoadjuvant immunotherapy across cancer types (Nature Cancer, 2025) and co-author of a commentary on early successes in colon immunotherapy (Nature Medicine, 2026).
• Tumor-infiltrating lymphocytes in gastro-oesophageal cancer: Co-investigator in the International Immuno-Oncology Biomarker Working Group’s recommendations for TIL assessment in gastro-oesophageal carcinoma (Histopathology, 2026).

Areas of Specialization

• Medical oncology — gastrointestinal cancers
• Neoadjuvant immunotherapy for colon, rectal, gastric, and gastroesophageal cancers
• Mismatch repair-deficient and mismatch repair-proficient tumor immunobiology
• Immune checkpoint blockade — anti-PD-1, anti-CTLA-4, anti-LAG-3 combinations
• Tumor microenvironment and translational biomarker research
• Clinical trial design and leadership in GI oncology
• Organ preservation strategies in rectal cancer
• Colorectal cancer genomics and molecular profiling (MSI/dMMR, KRAS)
• Innate and adaptive immune mechanisms in cancer immunotherapy

Publications

Dr. Chalabi has authored and co-authored publications in Nature, Nature Medicine, Nature Cancer, The Lancet, New England Journal of Medicine, Journal of Clinical Oncology, Clinical Cancer Research, JAMA Network Open, BMJ Open, BMC Cancer, Histopathology, and European Journal of Surgical Oncology.

Select Key Publications:

Chalabi M, Verschoor YL, Batista Tan P, van den Berg J, Haanen JB, et al. “Neoadjuvant Immunotherapy in Locally Advanced Mismatch Repair-Deficient Colon Cancer.” New England Journal of Medicine 390(21):1949–1958, June 2024. 391 citations.

de Gooyer P, Verschoor YL, van den Dungen LDW, Chalabi M, et al. “Neoadjuvant nivolumab and relatlimab in locally advanced MMR-deficient colon cancer: a phase 2 trial.” Nature Medicine 30(9):2509–2518, September 2024. 98 citations.

Tan PB, Verschoor YL, van den Berg J, Chalabi M, et al. “Neoadjuvant immunotherapy in mismatch-repair-proficient colon cancers.” Nature 636:203–212, October 2025. 19 citations.

Verschoor YL, van de Haar J, van den Berg J, Chalabi M, et al. “Neoadjuvant atezolizumab plus chemotherapy in gastric and gastroesophageal junction adenocarcinoma: the phase 2 PANDA trial.” Nature Medicine 30(1):96–109, January 2024. 122 citations.

André T, Elez E, Van Cutsem E, Lonardi S, Chalabi M (co-investigator), et al. “Nivolumab plus Ipilimumab in Microsatellite-Instability-High Metastatic Colorectal Cancer.” New England Journal of Medicine 392(2):165–177, November 2024. 199 citations.

André T, Elez E, Lenz HJ, Lonardi S, Chalabi M (co-investigator), et al. “Nivolumab plus ipilimumab versus nivolumab in microsatellite instability-high metastatic colorectal cancer (CheckMate 8HW): a randomised, open-label, phase 3 trial.” The Lancet 405(10492):2207–2217, January 2025. 166 citations.

de Vries N, van de Haar J, Veninga V, Voest EE, Chalabi M (co-investigator), et al. “γδ T cells are effectors of immunotherapy in cancers with HLA class I defects.” Nature 613:743–750, January 2023. 279 citations.

El Sissy C, Kirilovsky A, Lagorce Pagès C, Chalabi M (co-investigator), Pagès F, et al. “International Validation of the Immunoscore Biopsy in Patients With Rectal Cancer Managed by a Watch-and-Wait Strategy.” Journal of Clinical Oncology 41(30):4763–4774, October 2023. 40 citations.

Scott AJ, Kennedy EB, Berlin J, Gholami S, Chalabi M (panel member), et al. “Management of Locally Advanced Rectal Cancer: ASCO Guideline.” Journal of Clinical Oncology 42(23):2706–2731, August 2024. 144 citations.

Awada G, Cascone T, Van der Heijden M, Chalabi M (co-author), et al. “The rapidly evolving paradigm of neoadjuvant immunotherapy across cancer types.” Nature Cancer 6:986–1005, June 2025. 26 citations.

Chalabi M. “Early successes in colon immunotherapy.” Nature Medicine, January 2026.

de Back T, Nijskens I, Schafrat P, Sommeijer D, Chalabi M (co-investigator), et al. “Evaluation of Systemic Treatments of Small Intestinal Adenocarcinomas: A Systematic Review and Meta-analysis.” JAMA Network Open 6(2):e2254573, February 2023. 23 citations.

Zeverijn LJ, Geurts BS, Battaglia TW, Voest EE, Chalabi M (co-investigator), et al. “The Innate Immune Landscape of dMMR/MSI Cancers Predicts the Outcome of Nivolumab Treatment: Results from the Drug Rediscovery Protocol.” Clinical Cancer Research 30(16):3580–3591, July 2024. 6 citations.

Weeda Y, Salgado R, van Herpe F, Meijer SL, Chalabi M (co-author), et al. “Making sense of TILs: recommendations for morphological assessment of tumour-infiltrating lymphocytes in gastro-oesophageal carcinoma.” Histopathology, February 2026.

de Gooyer PG, van den Dungen LD, Geukes Foppen MH, Chalabi M, et al. “Neoadjuvant botensilimab plus balstilimab in MMR proficient and deficient early stage cancers: First results of the pan-cancer NEOASIS study.” Cancer Research 85(8_Suppl_2):CT130, AACR 2025.

All information is sourced from publicly available materials.