title: SPIRITT: A Randomized, Multicenter, Phase II Study of Panitumumab with FOLFIRI and Bevacizumab with FOLFIRI as Second-Line Treatment in Patients with Unresectable Wild Type KRAS Metastatic Colorectal Cancer.
abstract: BACKGROUND
  Second-line treatment with chemotherapy and anti-epidermal growth factor receptor or anti-vascular endothelial growth factor antibodies improves outcomes in patients with wild type Kirsten rat sarcoma viral oncogene homolog (KRAS) metastatic colorectal cancer (mCRC). The choice of biological agent in second-line mCRC remains unclear. In this randomized, phase II estimation trial, we compared FOLFIRI (irinotecan, 5-fluorouracil, and leucovorin) in combination with panitumumab or bevacizumab in patients with disease progression during oxaliplatin-based chemotherapy and bevacizumab.
  
  
  METHODS
  One hundred eighty-two patients were randomized to FOLFIRI with panitumumab or bevacizumab. The primary end point was progression-free survival (PFS). Secondary end points included overall survival (OS), objective response rate (ORR), and safety.
  
  
  RESULTS
  PFS was similar between arms, with a hazard ratio (HR) of 1.01 (95% confidence interval [CI], 0.68-1.50; P = .97). Median PFS was 7.7 months (95% CI, 5.7-11.8) in the panitumumab arm and 9.2 months (95% CI, 7.8-10.6) in the bevacizumab arm. OS was also similar between arms, with an HR of 1.06 (95% CI, 0.75-1.49; P = .75). Median OS was 18.0 months (95% CI, 13.5-21.7) in the panitumumab arm and 21.4 months (95% CI, 16.5-24.6) in the bevacizumab arm. ORR was 32% (95% CI, 23%-43%) in the panitumumab arm and 19% (95% CI, 11%-29%) in the bevacizumab arm. Skin disorders, diarrhea, hypomagnesemia, hypokalemia, dehydration, and hypotension were more frequent in the panitumumab arm. Neutropenia was more frequent in the bevacizumab-containing arm.
  
  
  CONCLUSIONS
  Panitumumab or bevacizumab with FOLFIRI as second-line treatment had efficacy similar in patients whose disease progressed during oxaliplatin-based chemotherapy with bevacizumab, with expected toxicities. The development of more accurate biomarkers might help caregivers and patients to better choose between therapies for individual patients.
authors.affiliation: David Geffen School of Medicine at UCLA, Santa Monica, CA. Electronic address: jrhecht@mednet.ucla.edu.
authors.forename: J Randolph
authors.initials: JR
authors.lastname: Hecht
authors.affiliation: Rocky Mountain Cancer Centers, Denver, CO.
authors.forename: Allen
authors.initials: A
authors.lastname: Cohn
authors.affiliation: Cancer Center of Kansas, Liberal, KS.
authors.forename: Shaker
authors.initials: S
authors.lastname: Dakhil
authors.affiliation: Georgia Cancer Specialists, Atlanta, GA.
authors.forename: Mansoor
authors.initials: M
authors.lastname: Saleh
authors.affiliation: Montefiore Medical Center, Bronx, NY.
authors.forename: Bilal
authors.initials: B
authors.lastname: Piperdi
authors.affiliation: Texas Oncology, Round Rock, TX.
authors.forename: Mika
authors.initials: M
authors.lastname: Cline-Burkhardt
authors.affiliation: Amgen Inc, Thousand Oaks, CA.
authors.forename: Ying
authors.initials: Y
authors.lastname: Tian
authors.affiliation: Amgen Inc, Thousand Oaks, CA.
authors.forename: William Y
authors.initials: WY
authors.lastname: Go
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000911:Antibodies, Monoclonal / Q000008:administration & dosage; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D000068258:Bevacizumab / Q000008:administration & dosage; D002166:Camptothecin / Q000008:administration & dosage / Q000031:analogs & derivatives; D015179:Colorectal Neoplasms / Q000188:drug therapy* / Q000473:pathology; D066246:ErbB Receptors / Q000037:antagonists & inhibitors; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage; D005500:Follow-Up Studies; D006801:Humans; D000077146:Irinotecan; D002955:Leucovorin / Q000008:administration & dosage; D008113:Liver Neoplasms / Q000188:drug therapy* / Q000556:secondary; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D009944:Organoplatinum Compounds / Q000008:administration & dosage; D000077150:Oxaliplatin; D000077544:Panitumumab; D011379:Prognosis; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D016283:Proto-Oncogene Proteins p21(ras); D016879:Salvage Therapy; D015996:Survival Rate; D018631:ras Proteins / Q000235:genetics*
chemical_list: D000911:Antibodies, Monoclonal; C117307:KRAS protein, human; D009944:Organoplatinum Compounds; D011518:Proto-Oncogene Proteins; D000077150:Oxaliplatin; D000068258:Bevacizumab; D000077544:Panitumumab; D000077146:Irinotecan; C512478:EGFR protein, human; D066246:ErbB Receptors; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins; D002955:Leucovorin; D005472:Fluorouracil; D002166:Camptothecin
keywords: EGFR; VEGF; WT; metastatic colorectal cancer