AACR 2026: Pembrolizumab Bowel Cancer Success, Moderna Melanoma Data

Key Takeaways

• Pembrolizumab (Keytruda) demonstrates zero relapses in the NEOPRISM-CRC bowel cancer trial after approximately three years of follow-up.
• Moderna's mRNA-4359 in combination with pembrolizumab (Keytruda) shows an 83% objective response rate (ORR) in first-line advanced/metastatic melanoma.
• Revolution Medicines' daraxonrasib doubles median survival compared to chemotherapy in second-line pancreatic cancer.
• Immune checkpoint inhibitor (ICI) therapy-related myocarditis risk is highest in the first 30 days of treatment and predicts increased fatality.

The American Association for Cancer Research (AACR) Annual Meeting 2026 is taking place from April 17-22 in San Diego, California, showcasing the latest breakthroughs in cancer research. Several key studies have been presented, highlighting advancements in immunotherapy, targeted therapies, and the use of artificial intelligence in oncology. This article summarizes the most impactful findings reported as of April 21st.

Event Context and Significance

The AACR Annual Meeting is a crucial event for the oncology community, bringing together researchers, clinicians, and industry professionals to share cutting-edge research and discuss the future of cancer treatment. The 2026 meeting features presentations on a wide range of topics, from basic science discoveries to clinical trial results, providing valuable insights into new approaches for preventing, diagnosing, and treating cancer.

Pembrolizumab in Bowel Cancer

The NEOPRISM-CRC trial, led by UCL/UCLH, investigated the use of pre-operative pembrolizumab (Keytruda) in patients with stage II/III mismatch repair deficient bowel cancer. After approximately three years of follow-up, the trial reported zero relapses in patients treated with pembrolizumab for nine weeks prior to surgery [2]. The study also observed a 59% pathological complete response rate. Furthermore, personalized circulating tumor DNA (ctDNA) tests were shown to predict treatment response [2, 8].

Moderna's mRNA-4359 for Melanoma

Moderna presented promising Phase 1/2 trial results for its mRNA-4359 in combination with pembrolizumab (Keytruda) as a first-line treatment for advanced or metastatic melanoma. The combination therapy achieved an 83% objective response rate (ORR) and a 92% disease control rate. The trial also reported two complete responses [4]. The FDA has granted fast track designation to mRNA-4359.

Revolution Medicines' Daraxonrasib in Pancreatic Cancer

Revolution Medicines announced that daraxonrasib doubled median survival compared to chemotherapy in patients with second-line pancreatic cancer, representing an increase of approximately six months [3].

Additional Notable Updates

• Oral Precancer Immunotherapy: A Phase I trial demonstrated that direct injection of an oral precancer immunotherapy can shrink lesions, potentially avoiding the need for surgery [6, 7].
• AI in Oncology: A plenary session highlighted the revolutionary impact of artificial intelligence tools in cancer research and clinical practice [8].
• ICI Therapy and Myocarditis: Research from Oklahoma University Stephenson indicated that myocarditis occurring within the first 30 days of immune checkpoint inhibitor (ICI) therapy is a strong predictor of fatality [1, 9]. This finding underscores the importance of early detection and management of this serious adverse event.
• Revolution Medicines' Zoldonrasib: An update to the Phase 1 trial of zoldonrasib in lung cancer showed a 52% confirmed ORR and 93% disease control [4].
• Insilico Medicine: Presented preclinical data on ISM3830 (Cbl-b inhibitor) and ISM6210 (CDK4 inhibitor) [5].
• Avacta Therapeutics: Presented preclinical and Phase 1 updates on AVA6103 (FAP-EXd) [1, 6].
• ImmunoScape: Presented data on a novel 'Seed-and-Boost' immunotherapy approach [2, 7].
• Foghorn Therapeutics: Presented new preclinical data for selective SMARCA2 inhibitor FHD-909 [9].

Market & Investor Implications

The positive data presented at AACR 2026 is likely to have a positive impact on the stock prices of the companies involved, particularly Moderna and Revolution Medicines. The advancements in immunotherapy and targeted therapies also suggest a continued shift towards personalized medicine in cancer treatment.

What to Watch Next

The AACR Annual Meeting 2026 continues through April 22nd. Further updates are expected, particularly from ongoing clinical trials and presentations in plenary sessions. Monitoring real-time pharma trial NCTs will provide additional insights into the evolving landscape of cancer research.

Frequently Asked Questions

• What is the significance of the NEOPRISM-CRC trial results?

  The NEOPRISM-CRC trial demonstrated the potential of pre-operative pembrolizumab (Keytruda) to eliminate detectable cancer cells in patients with mismatch repair deficient bowel cancer, resulting in zero relapses after approximately three years.

• What is the objective response rate (ORR) of Moderna's mRNA-4359 in melanoma?

  Moderna's mRNA-4359, in combination with pembrolizumab (Keytruda), achieved an 83% objective response rate (ORR) in first-line advanced/metastatic melanoma.

• How does daraxonrasib improve survival in pancreatic cancer?

  Daraxonrasib doubled the median survival compared to chemotherapy in patients with second-line pancreatic cancer, representing an increase of approximately six months.

• Why is early detection of myocarditis important in ICI therapy?

  Myocarditis occurring within the first 30 days of immune checkpoint inhibitor (ICI) therapy is a strong predictor of fatality, making early detection and management crucial.

• Where can I find more information about the AACR Annual Meeting 2026?

  Additional information can be found on the AACR website and through live blogs covering the event.

References

• [1] AACR 2026 Live Updates
• [2] AACR 2026: Bowel Cancer Trial Shows Zero Relapses
• [3] AACR 2026: Pancreatic Cancer and Other Highlights
• [4] AACR 2026: Moderna, Revolution, and Others Present New Data
• [5] Insilico Medicine Showcases Preclinical Data at AACR 2026
• [6] Avacta Therapeutics Data at AACR 2026
• [7] ImmunoScape Presents Data at AACR Annual Meeting
• [8] Personalis Highlights Clinical Impact of ctDNA Monitoring at AACR 2026
• [9] Foghorn Therapeutics Presents New Preclinical Data at AACR 2026