PD-0006 - Panitumumab plus FOLFOX4 or panitumumab plus FOLFIRI in subjects with wild-type KRAS (exon 2) colorectal cancer and multiple or unresectable liver-l...

Date 27 June 2014
Event World GI 2014
Session Poster discussion session 1 – EGFR-targeted agents
Topics Anti-Cancer Agents & Biologic Therapy
Colon Cancer
Rectal Cancer
Presenter Albert Abad
Citation Annals of Oncology (2014) 25 (suppl_2): ii5-ii13. 10.1093/annonc/mdu164
Authors A. Abad1, L. Robles2, T. Cano3, A. Carrato4, B. Massutí5, P. Escudero6, L. Layos7, M.A. Gomez8, M.J. Safont9, J. Sastre10, C. Pericay11, R. Dueñas12, F. Losa13, M. Valladares14, A. Yuste15
  • 1Hospital Sanitas Milenium Iradier, Barcelona/ES
  • 2Hospital 12 de Octubre, Madrid/ES
  • 3Hospital Universitario Reina Sofía, Córdoba/ES
  • 4Hospital Ramón y Cajal, Madrid/ES
  • 5H. General Universitario de Alicante, Alicante/ES
  • 6Hospital Clínico Universitario Lozano Blesa, Zaragoza/ES
  • 7ICO. Hospital Germans Trias i Pujol, Badalona/ES
  • 8H. Reina Sofia, Cordoba/ES
  • 9Hospital General de Valencia, Valencia/ES
  • 10Servicio de Oncología Médica HC, Madrid/ES
  • 11Corporació Sanitària Parc Taulí, Institut Universitari UAB, Sabadell/ES
  • 12Complejo Hospitalario de Jaén, Jaén/ES
  • 13H General de L'Hospitalet, Hospitalet de Llobregat, Llobregat/ES
  • 14Complejo Hospitalario Universitario La Coruña, La Coruña/ES
  • 15Hospital General Universitario de Alicante, Alicante/ES

Abstract

Introduction

Patients with colorectal cancer (CRC) and multiple or unresectable liver-limited metastases may benefit from downsizing the tumour with chemotherapy (CT) to permit resection and prolonged survival. The aim of the study was to evaluate the efficacy and safety of adding panitumumab (Pmab) to the standard CT in this setting.

Methods

The PLANET was a multicenter, randomized, open-label, phase II study which included patients ≥ 18 years with wild-type (WT) KRAS exon 2 metastatic CRC (mCRC) and liver-limited disease (LLD) fulfilling one of the following criteria: ≥4 metastases; at least 1 metastasis > 10 cm in diameter; or technically not resectable. Patients were randomized 1:1 to receive Pmab-FOLFOX4 or Pmab-FOLFIRI every 2 weeks. The primary endpoint was the objective response rate in WT KRAS (exon 2) patients. Efficacy results were also analyzed according to RAS status (exons 2, 3, 4 of KRAS/NRAS).

Results

77 patients were analyzed (38 received Pmab-FOLFOX4 and 39 Pmab-FOLFIRI). The main efficacy results are presented in the Table. Similar response and resection rates were observed for the two groups. Surgeries took place after a median of 8 Pmab infusions in both groups. Median progression-free survival (PFS) and preliminary median overall survival (OS) were also comparable (p = 0.943 and p = 0.848, respectively). It was possible to determine the RAS status in 83.1% of patients. Median pre-surgery relative dose-intensity (RDI) for Pmab was 79.8% with Pmab-FOLFOX4 and 87.5% with Pmab-FOLFIRI, and RDI for CT was 83.0% and 88.7%. Peri-operative safety was similar (22.2% and 18.5% of patients with any adverse event with Pmab-FOLFOX4 and Pmab-FOLFIRI, respectively). The only grade 3/4 adverse events with statistically significant differences between groups were: neutropenia grade 3/4 (Pmab-FOLFOX4 39.5% vs Pmab-FOLFIRI 10.3%; p = 0.0029) and neuropathy (Pmab-FOLFOX4 13.2% vs Pmab-FOLFIRI 0%;p = 0.025).

Conclusion

In patients with WT KRAS CRC and multiple or unresectable liver-limited metastases, both Pmab-FOLFOX4 and Pmab-FOLFIRI permit rapid tumour shrinkage and potentially curative hepatic resection, with similar efficacy and safety results between the two regimens.