Analysis of neurosensory adverse events induced by FOLFOX4 treatment in colorectal cancer patients: a comparison between two Asian studies and four Western studies.

The grades of neurosensory adverse events (NSAEs) induced by FOLFOX4 treatment were compared between Asian and Western colorectal cancer patients and correlated with cumulative oxaliplatin doses. A total of 3359 patients treated with FOLFOX4 were analyzed: 1515 from two Asian studies (Japanese Post Marketing Surveillance [J-PMS] and MASCOT) and 1844 from four Western studies (EFC2962, N9741, EFC4584, and MOSAIC). The onset of NSAEs was analyzed in terms of treatment duration and cumulative dose of oxaliplatin. The incidence of grade ≥3 NSAEs ranged from 2.0% to 4.4% in Asian studies and 9.3% to 19% in Western studies. The cumulative doses of oxaliplatin that induced grade ≥3 NSAEs in 10% of patients were higher in Asian studies (1526 mg/m(2) or not reached) than in Western studies (805-832 mg/m(2)). No significant correlations were noted between occurrence of grade ≥3 NSAEs and demographic/baseline characteristics. The frequency of escalation from grade 0 to 1 in J-PMS was statistically significantly lower than that in EFC4584, and that from grade 0 to 1 and from grade 1 to 2 in MASCOT lower than that in MOSAIC. The cumulative oxaliplatin doses administered during grade escalation in J-PMS were similar to those in EFC2962 or EFC4584. All grade-3 NSAEs in MASCOT and 96% of those in MOSAIC improved to grade 2 or less within 12 months of follow-up. The Asian populations accrued to these studies appear to be less susceptible to the neurotoxicity of oxaliplatin than the mainly Caucasian populations in the Western studies.

Safety analysis of FOLFOX4 treatment in colorectal cancer patients: a comparison between two Asian studies and four Western studies.

PURPOSE: Oxaliplatin-based therapy, notably FOLFOX4 (5-fluorouracil, leucovorin, and oxaliplatin), is a standard regimen approved globally for the treatment of metastatic colorectal cancer, and as adjuvant treatment of colon cancer. As part of the Japanese submission for the adjuvant indication, the safety profile of FOLFOX4 regimen was compared in Asian and Western patients. PATIENTS AND METHODS: A total of 3359 patients with colorectal cancer treated with the FOLFOX4 regimen were included in the analyses: 1515 from 2 Asian studies (Japanese Post Marketing Surveillance and Multicenter Asia Study in Adjuvant Treatment of Colon Cancer with Oxaliplatin/5-FU/LV), and 1844 from 4 Western studies (EFC2962, N9741, EFC4584, and Multicenter International Study of Oxaliplatin/5-Fluorouracil/Leucovorin in the Adjuvant Treatment of Colon Cancer). Doses administered and safety parameters were analyzed by using common definitions and programs. RESULTS: Demographic and baseline characteristics were comparable between Asian and Western patients. Patients received FOLFOX4 for a median of 6-12 cycles, which ranged from 16 to 28 weeks. Median dose intensities of oxaliplatin and of 5-fluorouracil, bolus and infusion, were within the ranges of 33 to 36 mg/m(2)/week, 297 to 338 mg/m(2)/week, and 467 to 510 mg/m(2)/week, respectively. Most frequently reported adverse events (AE) included hematologic, gastrointestinal, and neurosensory adverse events (NSAE). The incidence of grade ≥3 neutropenia ranged from 37% (422 of 1134) to 52% (83 of 159) in Asian and 41% (455 of 1108) to 56% (144 of 259) in Western studies; of diarrhea, ranged from 1.4% (3 of 222) to 6.3% (10 of 159) and 11% (30 of 268 or 120 of 1108) to 14% (36 of 259); of NSAEs, from 1.9% (21 of 1134) to 4.4% (7 of 159) and 9.3% (25 of 268) to 19% (39 of 209); and of allergic reactions, from 0.6% (7 of 1134) to 3.1% (5 of 159) and 1.1% (3 of 268) to 3.0% (33 of 1108), respectively. The probability of grade ≥3 NSAEs and diarrhea was statistically significantly lower in Asian than in Western studies by using a log-rank test. CONCLUSION: There was no evidence that Asian patients experienced worse toxicity than did Western patients when treated with FOLFOX4, and trends toward reduced neurotoxicity and diarrhea among Asian patients were observed.