A new hope for colorectal cancer with KRAS G12C

Colorectal cancer is one of the leading causes of cancer deaths worldwide, and new treatments are always needed to help patients live longer and healthier lives. Scientists are now focusing on a tiny change in the DNA of some people with colorectal cancer: a mutation called KRAS G12C. Let’s explore how new research is offering fresh hope for these patients by using a medicine called garsorasib, sometimes combined with another drug called cetuximab.

Understanding the KRAS G12C mutation in colorectal cancer

Colorectal cancer (CRC) affects about 10% of people diagnosed with cancer each year. A lot of CRC cases involve changes in the KRAS gene, and one rare change, KRAS G12C, is found in about 2–4% of patients. This particular mutation makes the cancer more aggressive and harder to treat. People with KRAS G12C mutations usually do not respond well to traditional treatments, and their tumors often grow despite several rounds of chemotherapy.

Why is KRAS G12C hard to treat?

For decades, doctors called KRAS “undruggable” because its structure did not allow medicines to stick to it and block its action. But in 2013, researchers discovered a special pocket on the KRAS G12C protein that new drugs could target (key discovery in Nature). This finding changed the way scientists approached the problem, leading to the development of new medicines designed just for this mutation.

Introducing garsorasib: a new targeted therapy

Garsorasib is a medicine specially designed to attach to the KRAS G12C mutation and stop it from helping cancer grow. In a recent phase II clinical trial (original study in Signal Transduction and Targeted Therapy), researchers tested garsorasib in people with advanced colorectal cancer that had the KRAS G12C mutation. Some patients took only garsorasib, and others took garsorasib plus cetuximab, which is a medicine that blocks another cancer growth signal called EGFR.

How did patients do on garsorasib—alone and in combination?

In the study, 26 people received garsorasib alone and 42 received the combination of garsorasib and cetuximab. Here’s what happened:

• About 19% of the patients on garsorasib alone saw their tumors shrink, while about 45% of those on the combination had their tumors shrink.

• Most patients in both groups had their disease stop getting worse for several months (disease control rate was over 92% in both groups).

• The average time before the cancer started growing again (progression-free survival) was 5.5 months with garsorasib alone and 7.5 months for the combination.

• The treatment was generally safe, with most side effects being mild or moderate, such as changes in liver function or skin issues. Serious side effects were rare and could be managed by adjusting the medicine dose.

Why does combining garsorasib and cetuximab work better?

Scientists found that when you block KRAS G12C with garsorasib, the cancer sometimes finds a way around the treatment by using a different path called the EGFR pathway. Cetuximab blocks that path, making it harder for the cancer to escape treatment. This strategy of blocking two signals at once led to better results in this study and in other research, too. For example, a similar combination showed promising outcomes in other trials, such as the divarasib plus cetuximab phase 1b trial and the D-1553 in pancreatic cancer study.

What it means for patients

While garsorasib and its combinations are not yet standard treatment, these results give hope to patients with advanced colorectal cancer that carries the KRAS G12C mutation. More studies are planned to confirm the benefits and make sure the medicine is safe for everyone. As health AI tools like SlothMD help patients and doctors track new options, it’s wise to learn how to keep your health information safe. For tips on protecting your data when using health AI, check out this helpful article on how to keep your health data private with AI. If you want to know more about your rights as a patient in the digital age, you might also enjoy reading your health data rights in an AI world.

Looking forward

The story of garsorasib is a reminder of how science and technology continue to bring new solutions to tough medical problems. With ongoing research, better medicines, and smart tools like SlothMD, the future for patients with difficult-to-treat cancers is brighter than ever.