An Open-Label Study to Characterize the Incidence and Severity of Diarrhea in Patients With Early-Stage HER2+ Breast Cancer Treated With Neratinib and Loperamide

Percentage of Patients With Diarrhea by Grade, According to the National Cancer Institute Common Terminology Criteria (NCI CTCAE), Version 4.0.

Assess the percentage of patients with diarrhea after the administration of an anti-inflammatory agent, a bile acid sequestrant, or following two different dose-escalation regimens of neratinib, by maximum CTC grade. Grade 1: an increase of \<4 stools per day over baseline; mild increase in ostomy output compared to baseline. Grade 2: Increase of 4 - 6 stools per day over baseline; moderate increase in ostomy output compared to baseline. Grade 3: Increase of \>=7 stools per day over baseline; incontinence; hospitalization indicated; severe increase in ostomy output compared to baseline; limiting self care ADL. Grade 4: Life-threatening consequences; urgent intervention indicated. Grade 5: Death.

Time frame: From first dose of investigational product through 28 days after last dose, up to 15.5 months.

Percentage of Patients With Serious Adverse Events and Other Adverse Events of Special Interest

Assess the percentage of patients with serious adverse events (SAEs) and other adverse events of special interest (AESI). AESIs were selected based on the known safety profile of neratinib as well as typical key body system toxicity concerns generally reviewed for any new drug. These AESIs were grouped into the following categories: gastrointestinal toxicity (diarrhea and stomatitis), hepatotoxicity, pulmonary toxicity (interstitial lung disease), cardiac toxicity (LVEF decreased), and dermatologic toxicity (rash and nail disorders). The AESIs were analyzed by searching the clinical database for all TEAEs and SAEs using either Standardized MedDRA Queries (SMQs) or, if an applicable SMQ did not exist, a Sponsor-defined list of MedDRA preferred terms.