Dr. Barcenas on Neratinib-Related Diarrhea in HER2+ Breast Cancer

Carlos Barcenas, MD, assistant professor, Department of Breast Medical Oncology, Division of Cancer Medicine, The University of Texas MD Anderson Cancer Center, discusses side effects of neratinib in patients with HER2-positive early-stage breast cancer.

Previously, the ExteNET study showed a benefit of neratinib in the adjuvant setting in patients with HER2-positive breast cancer stages I to III after a trastuzumab (Herceptin)-based therapy. About 40% of patients on neratinib experienced a rise in incidence and severity of diarrhea. In an effort to keep patients on neratinib for at least 1 year, 2 cohorts were given either loperamide alone or loperamide plus budesonide (Pulmicort) to control symptoms.

In the single-agent cohort, loperamide was given for 2 cycles at 4 mg 3 times per day for days 1 to 14, followed by 4 mg twice daily for days 15 to 56. In the combination cohort, budesonide was given at 9 mg once per day for 1 cycle, and loperamide was given as needed at ≤16 mg per day after 2 cylces.

According to Barcenas, the hope is that once neratinib is FDA approved, there will be a sound strategy to control the diarrhea while on the drug. The preliminary results look promising, but the study is still accruing patients.