Dr. Strickler on the Benefit of Combining Tucatinib With Trastuzumab in HER2+ CRC

John H. Strickler, MD, associate professor of medicine, Duke University School of Medicine, medical oncologist, Duke Cancer Institute, discusses the benefit of combining tucatinib (Tukysa) with trastuzumab (Herceptin) in HER2-positive metastatic colorectal cancer (mCRC).

The phase 2 MOUNTAINEER trial (NCT03043313) examined the efficacy of tucatinib monotherapy and in combination with trastuzumab in patients with previously treated HER2-positive mCRC.

Although tucatinib monotherapy elicited a low overall response rate, the disease control rate for the single agent was 80%, Strickler says, adding that non-responders to single-agent tucatinib could be converted to responders with the addition of trastuzumab, Strickler explains. These findings confirmed that combining tucatinib and trastuzumab from the outset is the optimal strategy for previously treated patients with HER2-positive mCRC, Strickler explains.

The addition of trastuzumab to tucatinib was well-tolerated, and patients maintained a good quality of life due to manageable adverse effects, Strickler concludes.