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.

Oxaliplatin plus irinotecan compared with irinotecan alone as second-line treatment after single-agent fluoropyrimidine therapy for metastatic colorectal carcinoma.

UNLABELLED: PURPOSE To determine whether irinotecan plus oxaliplatin (IROX) is superior to irinotecan alone in patients with metastatic colorectal cancer (CRC) previously treated with single-agent fluoropyrimidines. PATIENTS AND METHODS A phase III, randomized, open-label, multicenter study of patients with metastatic or recurrent CRC that had progressed or recurred during or after adjuvant or first-line fluoropyrimidines (fluorouracil/leucovorin or capecitabine, the latter only for metastatic CRC). Patients received IROX (irinotecan 200 mg/m(2) plus oxaliplatin 85 mg/m(2)) or irinotecan alone (350 mg/m(2)) every 3 weeks. RESULTS: At the data cutoff (when 447 of 628 randomly assigned patients had died), median overall survival was 13.4 months (95% CI, 12.4 to 14.7 months) and 11.1 month (95% CI, 10.0 to 12.7 months) in the IROX and irinotecan groups, respectively (hazard ratio = 0.78; 95% CI, 0.65 to 0.94; P = .0072). Overall response rate (22% v 7%, respectively; P < .0001), median time to progression (5.3 v 2.8 months, respectively; P < .0001), and improvement in tumor-related symptoms (32% v 19%, respectively; P = .0072) were also improved with IROX as compared with irinotecan. With the exception of granulocytopenia (25% v 13%), diarrhea (28% v 23%), and sensory disturbances (5% v 0%), grade 3 to 4 toxicities were comparable between the IROX and irinotecan groups, respectively. CONCLUSION IROX is an effective treatment for metastatic CRC that has progressed after first-line fluoropyrimidine therapy. IROX improves efficacy compared with irinotecan alone, providing an additional option in the postadjuvant or second-line treatment setting for patients who experience treatment failure with single-agent fluoropyrimidine therapy.

Potential regional differences for the tolerability profiles of fluoropyrimidines.

PURPOSE: We conducted a retrospective analysis of safety data from randomized, single-agent fluoropyrimidine clinical trials (bolus fluorouracil/leucovorin [FU/LV] and capecitabine) to test the hypothesis that there are regional differences in fluoropyrimidine tolerability. METHODS: Treatment-related safety data from three phase III clinical studies were analyzed by multivariate analysis: two comparing capecitabine with bolus FU/LV in metastatic colorectal cancer (MCRC) and one comparing capecitabine plus oxaliplatin (XELOX) with bolus FU/LV as adjuvant treatment for colon cancer. The United States (US) was compared with non-US countries (all three studies) and with the rest of the world and East Asia (adjuvant study). RESULTS: In the MCRC studies (n = 1,189), more grade 3/4 adverse events (AEs; relative risk [RR], 1.77), dose reductions (RR, 1.72), and discontinuations (RR, 1.83) were reported in US versus non-US patients. Likewise, in the adjuvant colon cancer study (n = 1,864), more grade 3/4 AEs (RR, 1.47) and discontinuations (RR, 2.09) were reported in US versus non-US patients. After further dividing non-US patients into those in East Asia and the rest of the world, differential RRs for related grade 3/4 AEs, grade 4 AEs, and serious AEs were again observed, with East Asian patients having the lowest and US patients the highest RR. CONCLUSION: Regional differences exist in the tolerability profiles of fluoropyrimidines. More treatment-related toxicity was reported in the US compared with the rest of the world for bolus FU/LV and capecitabine in first-line MCRC and adjuvant colon cancer. In the adjuvant setting, a range of fluoropyrimidine tolerability was observed, with East Asian patients having the lowest, and US patients the highest, RR.

Pooled analysis of safety and efficacy of oxaliplatin plus fluorouracil/leucovorin administered bimonthly in elderly patients with colorectal cancer.

PURPOSE: Oxaliplatin, fluorouracil, and leucovorin are commonly used to treat advanced and resected colorectal cancer. This analysis compares the safety and efficacy of oxaliplatin plus fluorouracil/leucovorin administered bimonthly (FOLFOX4) in patients age younger than and at least 70 years. PATIENTS AND METHODS: This retrospective analysis included 3,742 colorectal cancer patients (614 age > or = 70) from four clinical trials testing FOLFOX4 in the adjuvant, first-, and second-line settings. End points included grade > or = 3 adverse events, response rate (in advanced disease), progression or relapse-free survival, dose-intensity, and overall survival in the studies with mature survival data. RESULTS: Grade > or = 3 hematologic toxicity (neutropenia [43% v 49%; P = .04] and thrombocytopenia [2% v 5%; P = .04]) were significantly higher in older patients. Older age was not associated with increased rates of severe neurologic adverse events, diarrhea, nausea/vomiting, infection, overall incidence of grade > or = 3 toxicity (63% v 67%; P = .15), or 60-day mortality (1.1% v 2.3%; P = .20). The relative benefit of FOLFOX4 versus control did not differ by age for response rate, progression or recurrence free-survival (hazard ratio, 0.70 for FOLFOX4 v control for age < 70, 0.65 for age > or = 70; P = .42), or overall survival (hazard ratio, 0.77 age < 70, 0.82 age > or = 70; P = .79). Dose-intensity did not differ by age at cycles 1, 3, 6, or 12. CONCLUSION: FOLFOX4 maintains its efficacy and safety ratio in selected elderly patients with colorectal cancer. Its judicious use should be considered without regard to patient age, although scant data are available among patients older than 80 years.

Improving the evaluation of new cancer treatments: challenges and opportunities.

There are, at present, ten times more anticancer drugs being tested in clinical trials than there were 15 years ago. Many of the new classes of agents, however, are predicted to work in only small subpopulations of patients, target unconventional aspects of tumour development and interact with other agents in an unpredictable manner. How can clinical trials be re-designed to accommodate the new features of targeted anticancer drugs?

Chemotherapeutic advances in pancreatic cancer.

Advances in chemotherapy for pancreatic cancer have been limited. In the past decade, the standard therapy for metastatic disease has switched from 5-fluorouracil (5-FU) to gemcitabine. However, several other cytotoxic agents have shown limited but promising efficacy in pancreatic cancer, and many of these appear to be well suited for combination chemotherapy. Although 5-FU and cisplatin have not demonstrated substantial survival benefits when combined with gemcitabine, results of several phase III trials with other agents are still pending. For locally advanced disease, most recent studies have incorporated gemcitabine into combined-modality therapy. Similarly, in surgically resectable disease, current trials are incorporating gemcitabine into adjuvant therapy. Other trials are using neoadjuvant therapy as a possible means to improve upon current surgical results. However, much hope comes from the development of newer "targeted" therapies for this disease. Although matrix metalloproteinase inhibitors and farnesyl transferase inhibitors did not appear to be effective in initial studies, other targeted therapies are beginning to enter clinical trials.

Current status of capecitabine in the treatment of colorectal cancer.

Capecitabine (Xeloda) is an oral prodrug that is enzymatically converted to fluorouracil (5-FU) within cancer cells. Data from two large phase III trials performed in patients receiving first-line chemotherapy for metastatic colorectal cancer showed that capecitabine yielded higher objective response rates and equivalent median time to tumor progression and overall survival rates as 5-FU/leucovorin. In these studies, capecitabine demonstrated lower rates of diarrhea, stomatitis, nausea, and severe neutropenia than bolus 5-FU/leucovorin, but a higher rate of hand-foot syndrome and hyperbilirubinemia. The natural extension of this work has been to evaluate substitution of capecitabine for 5-FU/leucovorin in combination chemotherapy trials with irinotecan (CPT-11, Camptosar) or oxaliplatin (Eloxatin). This is especially important due to concerns regarding toxicities observed with regimens that combine bolus 5-FU/leucovorin with irinotecan or oxaliplatin. Phase I/II and phase II trials of capecitabine in combination with irinotecan or oxaliplatin in patients with advanced disease indicate that the combinations are well tolerated and produce response rates that are in the range of those that would be expected with infusional 5-FU/leucovorin combined with irinotecan or oxaliplatin. Phase III trials have been initiated in the advanced disease and adjuvant settings and should help determine the efficacy, toxicity, and tolerability of the capecitabine/irinotecan or capecitabine/oxaliplatin combination in direct comparison to intravenous 5-FU/leucovorin and irinotecan or oxaliplatin.