When the Scan Is Clear, But Risk Remains

You completed surgery. You may have completed chemotherapy. Your scans show no evidence of cancer.

But for some patients with stage II or stage III colorectal cancer, tiny amounts of cancer may still remain in the body. These microscopic cancer cells cannot be seen on CT scans but can be detected through a blood test that measures circulating tumor DNA (ctDNA). This condition is known as minimal residual disease (MRD).

The COMBAT Trial is based on a simple but powerful idea: can immunotherapy eliminate cancer when only microscopic disease remains and provide the best chance to prevent recurrence in patients with ctDNA-positive colorectal cancer?

The combination of botensilimab and balstilimab has shown promising activity in colorectal cancer, a disease that has historically been difficult to treat with immunotherapy. COMBAT builds on advances in immunotherapy research in earlier-stage colon cancer by targeting remaining cancer cells before they become visible on scans.

The goal is to determine whether treating molecular residual disease can reduce the risk of recurrence and ultimately improve cure rates.

For patients with a positive ctDNA test, COMBAT offers the opportunity to take action before a recurrence becomes clinically detectable.

For Referring Providers

The COMBAT Trial is for patients with resected stage II or III colorectal cancer who:

  • Have completed standard curative-intent therapy
  • Remain ctDNA-positive following treatment (Signatera MTD Test is being used on study).
  • Have no radiographic evidence of disease

The study addresses one of the most important unanswered questions in colorectal cancer today: Can intervention at the minimal residual disease stage prevent recurrence and improve cure rates?