Dr. Salem on the Results of the MyPathway Trial in mCRC

Mohamed E. Salem, MD, a medical oncologist at Levine Cancer Institute, Atrium Health, discusses the results of the MyPathway trial in metastatic colorectal cancer (mCRC).

In terms of HER2, a lot of what is known in breast cancer is applicable in mCRC, explains Salem. In that space, physicians learned about HER2 as a physiology and how to target it. Through advances made in technology and the ability of next-generation sequencing, it was discovered that approximately 3% to 5% of patients have HER2 overexpression. Now, there are drugs that can target HER2-amplified tumors. For example, data from the HERACLES trial demonstrated the activity of anti-HER2 therapy in the refractory setting.

More recently, data from the MyPathway trial published in Lancet Oncology showed the activity of anti-HER2 therapy with trastuzumab (Herceptin) and pertuzumab (Perjeta) in patients with HER2-amplified tumors in the refractory setting. The objective response rate was about 32%. Moreover, 2% of patients achieved a complete response, and the disease control rate was about 40%. Although the sample size was small, there was a signal of activity that has to be weighed against historical response rates of 1%. The data also suggest a relationship between resistance to anti-EGFR therapy and RAS-wild type and HER2-amplified tumors, said Salem.