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Immunotherapy-Based Management of Gastric/GEJ Cancers

CME

Expert Think Tank: New Developments in Immunotherapy-Based Management of Gastric/GEJ Cancers Across the Disease Continuum

Physicians: Maximum of 0.50 AMA PRA Category 1 Credit

Released: June 26, 2026

Expiration: December 25, 2026

Activity

Progress
1 2 3
Course Completed

References

  1. Wang Y and Chong G. Immunotherapy in gastric adenocarcinoma - a rapidly evolving treatment landscape. Crit Rev Oncol Hematol. 2025;216:104941.
  2. Tabernero J, Al-Batran SE, Wainberg ZAA, et al. Final overall survival (OS) and the association of pathological outcomes with event-free survival (EFS) in MATTERHORN: a randomised, phase III study of durvalumab (D) plus 5-fluorouracil, leucovorin, oxaliplatin and docetaxel (FLOT) in resectable gastric / gastroesophageal junction (G / GEJ) adenocarcinoma. Ann Oncol. 2025;36:S1624.
  3. Schwengber WK, Pereira RA, Leite da Silva LF, et al. Neoadjuvant immune checkpoint inhibitors for localized dMMR/MSI-H gastric cancer: a meta-analysis. ESMO Open. 2026;11:106066.
  4. Andre T, Tougeron D, Piessen G, et al. Neoadjuvant nivolumab plus ipilimumab and adjuvant nivolumab in localized deficient mismatch repair/microsatellite instability-high gastric or esophagogastric junction adenocarcinoma: the GERCOR NEONIPIGA phase II study. J Clin Oncol. 2023;41:255-265.
  5. Coutzac C, Bibeau F, Abdelghani MB, et al. Immunotherapy in MSI/dMMR tumors in the perioperative setting: The IMHOTEP trial. Dig Liver Dis. 2022;54:1335-1341.
  6. Raimondi A, Lonardi S, Murgioni S, et al. Tremelimumab and durvalumab as neoadjuvant or non-operative management strategy of patients with microsatellite instability-high resectable gastric or gastroesophageal junction adenocarcinoma: the INFINITY study by GONO. Ann Oncol. 2025;36:285-296.
  7. Cercek A, Foote MB, Rousseau B, et al. Nonoperative management of mismatch repair-deficient tumors. N Engl J Med. 2025;392:2297-2308.
  8. National Comprehensive Cancer Network. Clinical practice guidelines in oncology: gastric cancer. v3.2026. nccn.org. Accessed June 24, 2026.
  9. Janjigian YY, Al-Batran S, Wainberg ZA. Perioperative durvalumab in gastric and gastroesophageal junction cancer. N Engl J Med. 2025;393:217-230.
  10. Durvalumab [prescribing information]. Wilmington, DE: AstraZeneca; 2025.
  11. Shitara K. CLARITY-Gastric 01: a randomized phase 3 study of sonesitatug vedotin (sone ve), a Claudin18.2 (CLDN18.2)-targeted drug conjugate, in second- or later-line (2L+) advanced gastric or gastroesophageal antibody junction cancer (GC/GEJC). Presented at: ESMO GI Congress; June 26-29, 2024. Abstract LBA3.
  12. Shitara K, Rha SY, Wyrwicz L, et al. Pembrolizumab plus chemotherapy versus chemotherapy as perioperative therapy in locally advanced gastric and gastroesophageal junction cancer: final analysis of the randomized, phase III KEYNOTE-585 study. J Clin Oncol. 2025;43:3152-3159.
  13. Raghav KPS and Moasser MM. Molecular pathways and mechanisms of HER2 in cancer therapy. Clin Cancer Res. 2023;29:2351-2361.
  14. Lordick F, Carneiro F, Cascinu S, et al. Gastric cancer: ESMO Clinical Practice Guideline for diagnosis, treatment and follow-up. Ann Oncol. 2022;33:1005-1020.
  15. European Society for Medical Oncology. Gastric cancer living guideline. v1.4; September 2024. esmo.org. Accessed June 24, 2026.
  16. Moran D, Maurus D, Rohde C, et al. 103P - Prevalence of CLDN18.2, HER2 and PD-L1 in gastric cancer samples. Annals Oncol. 2018;29:VII32.
  17. National Comprehensive Cancer Network. Clinical practice guidelines in oncology: esophageal and esophagogastric junction cancers. v3.2026. nccn.org. Accessed June 24, 2026.
  18. Pembrolizumab [prescribing information]. Whitehouse Station, NJ: Merck & Co., Inc.; 2025.
  19. Nivolumab [prescribing information]. Princeton, NJ: Bristol Myers Squibb; 2025.
  20. Tislelizumab [prescribing information]. San Carlos, CA: BeiGene USA, Inc.; 2025.
  21. Janjigian YY, Shitara K, Ajani JA. Nivolumab plus chemotherapy as first-line treatment for advanced gastric, gastroesophageal junction, and esophageal adenocarcinoma: 5-year follow-up results from CheckMate 649. Ann Oncol. 2026;37:787-797.
  22. Rha SY, Oh D, Yanez P, et al. Pembrolizumab plus chemotherapy versus placebo plus chemotherapy for HER2-negative advanced gastric cancer (KEYNOTE-859): a multicentre, randomised, double-blind, phase 3 trial. Lancet Oncol. 2023;24:1181-1195.
  23. Rha SY, Wyrwicz L, Weber PEY, et al. KEYNOTE-859: 4.5-year median follow-up of pembrolizumab plus chemotherapy for previously untreated advanced HER2-negative gastric or gastroesophageal junction (G/GEJ) adenocarcinoma. J Clin Oncol. 2025;43:4036.
  24. Cruz-Correa MR, Moehler MH, Denlinger CS, et al. Associations between ECOG performance status (PS) and patient-reported outcomes (PROs) in patients with gastric or gastroesophageal junction (G/CEJC) adenocarcinoma: Results from the RATIONALE-305 trial. J Clin Oncol. 2026;44:288.
  25. Janjigian YY, Kawazoe A, Bai Y, et al. Pembrolizumab in HER2-positive gastric cancer. N Engl J Med. 2024;391:1360-1374.
  26. Janjigian YY, Kawazoe A, Bai Y, et al. Pembrolizumab plus trastuzumab and chemotherapy for HER2-positive gastric or gastro-oesophageal junction adenocarcinoma: interim analyses from the phase 3 KEYNOTE-811 randomised placebo-controlled trial. Lancet. 2023;402:2197-2208.
  27. Casak SJ, Zhang Y, Song C, et al. FDA approval summary: pembrolizumab for the treatment of HER2-positive gastric cancer. Clin Cancer Res. 2026;32:1923-1930.
  28. Kawazoe A, Rha SY, Bai Y, et al. KEYNOTE-811: 6-year median follow-up of pembrolizumab plus trastuzumab and chemotherapy for previously untreated advanced HER2-positive gastric or gastroesophageal junction adenocarcinoma. J Clin Oncol. 2026;44:4040.
  29. Elimova E, Rha SY, Shitara K, et al. Zanidatamab + chemotherapy (CT) ± tislelizumab for first-line (1L) HER2-positive (HER2+) locally advanced, unresectable, or metastatic gastroesophageal adenocarcinoma (mGEA): Primary analysis from HERIZON-GEA-01. J Clin Oncol. 2026;44:LBA285.
  30. Tabernero J, Shen L, Elimova E, et al. HERIZON-GEA-01: Zanidatamab + chemo ± tislelizumab for 1L treatment of HER2-positive gastroesophageal adenocarcinoma. Future Oncol. 2022;18:3255-3266.
  31. Shitara K, Elimova E, Liu T, et al. Zanidatamab with and without Tislelizumab in HER2-Positive Gastroesophageal Cancer. N Engl J Med. 2026;394:2002-2013.
  32. Pembrolizumab and berahyaluronidase alfa [prescribing information]. Whitehouse Station, NJ: Merck & Co., Inc.; 2025.
  33. Nivolumab and hyaluronidase [prescribing information]. Princeton, NJ: Bristol Myers Squibb; 2025
  34. Chen M, Bulat I, Maglakelidze M, et al. Subcutaneously administered tislelizumab in locally advanced or metastatic non-small cell lung cancer: pharmacokinetics and safety results from the BGB-A317-103 phase I study. Clin Cancer Res. 2026;32:1678-1686.
  35. George S, Bourlan MT, Chacon MR et al. Subcutaneous nivolumab (NIVO SC) vs intravenous nivolumab (NIVO IV) in patients with previously treated advanced or metastatic clear cell renal cell carcinoma (ccRCC): pharmacokinetics (PK), efficacy, and safety results from CheckMate 67T. J Clin Oncol. 2024;42:LBA360.
  36. Albiges L, Bourlan MT, Chacon M, et al. Subcutaneous versus intravenous nivolumab for renal cell carcinoma. Ann Oncol. 2025;36:99-109.
  37. Adamczyk D, Bourlon MT, Albiges L, et al. Updated efficacy and safety results from CheckMate 67t: subcutaneous (sc) vs intravenous (iv) nivolumab (nivo) in patients with previously treated advanced or metastatic clear cell renal cell carcinoma (CCRCC) Presented at: Oncology Nursing Society Annual Congress; April 9-13, 2025. Abstract 16944.
  38. Felip E, Rojas CI, Schenker M, et al. Subcutaneous versus intravenous pembrolizumab, in combination with chemotherapy, for treatment of metastatic non-small-cell lung cancer: the phase III 3475A-D77 trial. Ann Oncol. 2025;36:775-786.
  39. Elantably D, Jones JC, Lou Y, et al. A pilot single-arm, pragmatic trial in progress of in-home versus in-clinic subcutaneous nivolumab administration through Cancer Care (connected access and remote expertise) Beyond Walls (CCBW) program. J Clin Oncol. 2025;43:TPS1657.
  40. Lonardi S, Ługowska I, O’Donnell A, et al. Pharmacokinetics and safety of subcutaneous nivolumab: results from the phase I/II CheckMate 8KX study. J Immunother Cancer. 2025;13:e011918.
  41. van Vugt MJH, Stone JA, De Greef RHJMM, et al. Immunogenicity of pembrolizumab in patients with advanced tumors. J Immunother Cancer. 2019;7:212.