Results of a phase II trial of trastuzumab (H) and pertuzumab (P) in patients (pts) with HER2-positive metastatic breast cancer (MBC) who had progressed during trastuzumab therapy

• DOI: 10.1200/jco.2008.26.15_suppl.1026
• Publication Date: 2017-02-24T07:33:44Z
• Authors: K. A. Gelmon; P. Fumoleau; S. Verma; A. M. Wardley; P. F. Conte; D. Miles; L. Gianni; V. A. McNally; G. Ross; J. Baselga
• Keywords: 03 medical and health sciences; 0302 clinical medicine; 3. Good health

1026 Background: P is a humanized monoclonal antibody that binds to the specific dimerization epitope of HER2, blocking HER2 homo- and heterodimerization, thus preventing signal transduction. Xenograft studies indicate that the complementary mechanisms of action of P and H have a synergistic effect. Methods: This single-arm, Simon-type, two-stage phase II trial included pts with measurable, centrally tested HER2-positive MBC, ≥3 lines of prior therapy (including adjuvant therapy), disease progression during prior H therapy, and a baseline LVEF ≥55% that had not declined to <50% with H therapy. Consenting pts received H at 2 mg/kg qw (4 mg/kg loading dose [LD]) or 6 mg/kg q3w (8 mg/kg LD) plus P at 420 mg q3w (840 mg LD) starting within 9 weeks of the last dose of H. LVEF was assessed regularly in all pts. The primary endpoint was objective response and clinical benefit response rate (OR and SD ≥6 mths). Results: 66 pts have been enrolled and all have received ≥2 doses of study medication (41 are still on ...