New Therapy for HER2-Positive Breast Cancer?

Herceptin (trastuzumab) has revolutionized the treatment of HER2-positive breast cancer. However, some patients become resistant to the drug. Now, there's new hope for these women.

Scientists at the National Cancer Institute (NCI) have engineered and tested a new protein called HER2-Affitoxin. This combines HER2-specific molecules with a bacterial toxin known as PE38.

HER2-positive breast cancer patients may soon have new therapy.

Affitoxin is a targeted therapy that goes after the HER2 proteins.  Unlike current therapies including Herceptin, this protein doesn't interfere with HER2 activity. Instead it acts a smart bomb - going after the HER2-positive cells and killing them with the toxin.

Jacek Capala, Ph.D., D.Sc., the lead NCI investigator, says Affitoxin interferes with the HER2 protein production, which results in cell death.

These findings were seen in the lab. After Affitoxin was injected into mice with HER2-positive breast cancer, even large and aggressive tumors stopped growing and later disappeared. The results were so impressive and so positive, that Capala thinks a clinical trial should be conducted to confirm these laboratory findings.

He says Affitoxin could offer women who don't respond to Herceptin effective new therapeutic options.

This research is published Clinical Cancer Research, a journal of the American Association for Cancer Research.