There was 1 complete response in a PT with BC, partial responses in 4 pts (BC, 2; esophageal, 2), and stabilization of disease lasting 3 months or greater in 6 other pts. All but 1 response in pts with HER2 3+ disease. 2 pts completed 1 year of therapy. 10 pts had progressive disease. IL-12 + TRZ and PCTX exhibits an acceptable toxicity profile and has activity in pts with HER2-overexpressing CA. The gene discussed is ERBB2; the disease is breast cancer.