This phase III trial studied neratinib in patients with early-stage HER2-positive breast cancer; while initially all patients with stages 1–3 were eligible, a protocol amendment 7 months into the study restricted eligibility to higher-risk patients with stage 2–3, and patients who completed neoadjuvant chemotherapy were only eligible if there was pathological residual invasive disease at the time of surgery. The gene discussed is ERBB2; the disease is breast cancer.