First-Line XELOX Plus Bevacizumab Followed by XELOX Plus Bevacizumab or Single-Agent Bevacizumab as Maintenance Therapy in Patients with Metastatic Colorectal Cancer: The Phase III MACRO TTD Study

Disclosures: Eduardo Diaz-Rubio: Roche (C/A, RF); Auxiliadora Gomez-Espana: None; Bartomeu Massuti: Roche (C/A); Javier Sastre: None; Albert Abad: Roche (C/A); Manuel Valladares: Roche (C/A, RF, H); Fernando Rivera: Roche (C/A, RF); Maria J. Safont: None; Purificacion Martinez de Prado: None; Manuel Gallen: None; Encarnacion Gonzalez: None; Eugenio Marcuello: None; Manuel Benavides: Roche (C/A); Carlos Fernandez-Martos: None; Ferran Losa: None; Pilar Escudero: None; Antonio Arrivi: None; Andres Cervantes: Roche (H); Rosario Duenas: None; Amelia Lopez-Ladron: None; Adelaida Lacasta: None; Marta Llanos: None; Jose M. Tabernero: Roche, Genentech, Sanofi- Aventis (C/A); Antonio Anton: None; Enrique Aranda: Roche, Merck Serono (C/A). (C/A) Consulting/advisory relationship; (RF) Research funding; (E) Employment; (H) Honoraria received; (OI) Ownership interests; (IP) Intellectual property rights/inventor/patent holder; (SAB) Scientific advisory board. Purpose: The aim of this phase III trial was to compare the efficacy and safety of bevacizumab alone with those of bevacizumab and capecitabine plus oxaliplatin (XELOX) as maintenance treatment following induction chemotherapy with XELOX plus bevacizumab in the first-line treatment of patients with metastatic colorectal cancer (mCRC). Patients and Methods: Patients were randomly assigned to receive six cycles of bevacizumab, capecitabine, and oxaliplatin every 3 weeks followed by XELOX plus bevacizumab or bevacizumab alone until progression. The primary endpoint was the progression-free survival (PFS) interval; secondary endpoints were the overall survival (OS) time, objective response rate (RR), time to response, duration of response, and safety. Results: The intent-to-treat population comprised 480 patients (XELOX plus bevacizumab, n = 239; bevacizumab, n = 241); there were no significant differences in baseline characteristics. The median follow-up was 29.0 months (range, 0–53.2 months). There were no statistically significant differences in the median PFS or OS times or in the RR between the two arms. The most common grade 3 or 4 toxicities in the XELOX plus bevacizumab versus bevacizumab arms were diarrhea, hand–foot syndrome, and neuropathy. Conclusion: Although the noninferiority of bevacizumab versus XELOX plus bevacizumab cannot be confirmed, we can reliably exclude a median PFS detriment >3 weeks. This study suggests that maintenance therapy with singleagent bevacizumab may be an appropriate option following induction XELOX plus bevacizumab in mCRC patients.