Phase II trial of anti-idiotypic p53 peptides (Pentrys) plus granulocyte-macrophage colony-stimulating factor in patients with hormone-refractory prostate cancer

Abstract

Background: p53 overexpression occurs commonly in hormone-refractory prostate cancer (HRPC). T-cell responses against p53 could potentially mediate an antitumor effect. We investigated a novel system of vaccination using three peptides derived from a mouse-antihuman p53 antibody (Pentrys) in men with HRPC. Patients and methods: A phase II, single-arm, open-label study of Pentrys peptides admixed with granulocyte-macrophage colony-stimulating factor (GM-CSF) was injected intradermally in men with HRPC, rising prostate-specific antigen (PSA) and minimal symptoms. The primary objective was to determine clinical responses as measured by PSA. Secondary objectives were to determine duration of PSA..