Genome-wide association studies of toxicity to oxaliplatin and fluoropyrimidine chemotherapy with or without cetuximab in 1800 patients with advanced colorectal cancer

Chemotherapies administered at normal therapeutic dosages can cause significant side-effects and may result in early treatment discontinuation. Inter-individual variation in toxicity highlights the need for biomarkers to personalise treatment. We sought to identify such biomarkers by conducting 40 genome-wide association studies, together with gene and gene set analyses, for any toxicity and 10 individual toxicities in 1800 patients with advanced colorectal cancer treated with oxaliplatin and fluoropyrimidine chemotherapy ± cetuximab from the MRC COIN and COIN-B trials (385 patients received FOLFOX, 360 FOLFOX + cetuximab, 707 XELOX and 348 XELOX + cetuximab). Single nucleotide polymorphisms (SNPs), genes and gene sets that reached genome-wide or suggestive significance were validated in independent patient groups. We found that MROH5 was significantly associated with neutropenia in MAGMA gene analyses in patients treated with XELOX (P = 6.6 × 10^-7 ) and was independently validated in those receiving XELOX + cetuximab; pooled P = 3.7 × 10^-7 . rs13260246 at 8q21.13 was significantly associated with vomiting in patients treated with XELOX (odds ratio = 5.0, 95% confidence interval = 3.0-8.3, P = 9.8 × 10^-10 ) but was not independently replicated. SNPs at 139 loci had suggestive associations for toxicities and lead SNPs at five of these were independently validated (rs6030266 with diarrhoea, rs1546161 with hand-foot syndrome, rs9601722 with neutropenia, rs13413764 with lethargy and rs4600090 with nausea; all with pooled P's < 5.0 × 10^-6 ). In conclusion, the association of MROH5 with neutropenia and five other putative biomarkers warrant further investigation for their potential clinical utility. Despite our comprehensive genome-wide analyses of large, well-characterised, clinical trials, we found a lack of common variants with modest effect sizes associated with toxicities.

The clinical effectiveness and cost-effectiveness of cetuximab (review of technology appraisal no. 176) and panitumumab (partial review of technology appraisal no. 240) for previously untreated metastatic colorectal cancer: a systematic review and economic evaluation

BACKGROUND

Colorectal cancer is the fourth most commonly diagnosed cancer in the UK after breast, lung and prostate cancer. People with metastatic disease who are sufficiently fit are usually treated with active chemotherapy as first- or second-line therapy. Targeted agents are available, including the antiepidermal growth factor receptor (EGFR) agents cetuximab (Erbitux^®, Merck Serono UK Ltd, Feltham, UK) and panitumumab (Vecitibix^®, Amgen UK Ltd, Cambridge, UK).

OBJECTIVE

To investigate the clinical effectiveness and cost-effectiveness of panitumumab in combination with chemotherapy and cetuximab in combination with chemotherapy for rat sarcoma (RAS) wild-type (WT) patients for the first-line treatment of metastatic colorectal cancer.

DATA SOURCES

The assessment included a systematic review of clinical effectiveness and cost-effectiveness studies, a review and critique of manufacturer submissions, and a de novo cohort-based economic analysis. For the assessment of effectiveness, a literature search was conducted up to 27 April 2015 in a range of electronic databases, including MEDLINE, EMBASE and The Cochrane Library.

REVIEW METHODS

Studies were included if they were randomised controlled trials (RCTs) or systematic reviews of RCTs of cetuximab or panitumumab in participants with previously untreated metastatic colorectal cancer with RAS WT status. All steps in the review were performed by one reviewer and checked independently by a second. Narrative synthesis and network meta-analyses (NMAs) were conducted for outcomes of interest. An economic model was developed focusing on first-line treatment and using a 30-year time horizon to capture costs and benefits. Costs and benefits were discounted at 3.5% per annum. Scenario analyses and probabilistic and univariate deterministic sensitivity analyses were performed.

RESULTS

The searches identified 2811 titles and abstracts, of which five clinical trials were included. Additional data from these trials were provided by the manufacturers. No data were available for panitumumab plus irinotecan-based chemotherapy (folinic acid + 5-fluorouracil + irinotecan) (FOLFIRI) in previously untreated patients. Studies reported results for RAS WT subgroups. First-line treatment with anti-EGFR therapies in combination with chemotherapy appeared to have statistically significant benefits for patients who are RAS WT. For the independent economic evaluation, the base-case incremental cost-effectiveness ratio (ICER) for RAS WT patients for cetuximab plus oxaliplatin-based chemotherapy (folinic acid + 5-fluorouracil + oxaliplatin) (FOLFOX) compared with FOLFOX was £104,205 per quality-adjusted life-year (QALY) gained; for panitumumab plus FOLFOX compared with FOLFOX was £204,103 per QALY gained; and for cetuximab plus FOLFIRI compared with FOLFIRI was £122,554 per QALY gained. The ICERs were sensitive to treatment duration, progression-free survival, overall survival (resected patients only) and resection rates.

LIMITATIONS

The trials included RAS WT populations only as subgroups. No evidence was available for panitumumab plus FOLFIRI. Two networks were used for the NMA and model, based on the different chemotherapies (FOLFOX and FOLFIRI), as insufficient evidence was available to the assessment group to connect these networks.

CONCLUSIONS

Although cetuximab and panitumumab in combination with chemotherapy appear to be clinically beneficial for RAS WT patients compared with chemotherapy alone, they are likely to represent poor value for money when judged by cost-effectiveness criteria currently used in the UK. It would be useful to conduct a RCT in patients with RAS WT.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42015016111.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Oral versus intravenous fluoropyrimidines for colorectal cancer

BACKGROUND

Patients prefer oral to intravenous (IV) palliative chemotherapy, provided that oral therapy is not less effective. We compared the efficacy and safety of oral and IV fluoropyrimidines for treatment of colorectal cancer (CRC).

OBJECTIVES

To compare the effects of oral and IV fluoropyrimidine chemotherapy in patients treated with curative or palliative intent for CRC.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 5), along with OVID MEDLINE, OVID Embase, and Web of Science databases, in June 2016. We also searched five clinical trials registers, several conference proceedings, and reference lists from study reports and systematic reviews. We contacted pharmaceutical companies to identify additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing oral and IV fluoropyrimidine chemotherapy in patients treated with curative or palliative intent for CRC.

DATA COLLECTION AND ANALYSIS

Three review authors extracted data and assessed risk of bias independently. We assessed the seven domains in the Cochrane 'Risk of bias' tool and three additional domains: schedules of outcome assessment and/or follow-up; use of intention-to-treat analysis; and baseline comparability of treatment arms.

MAIN RESULTS

We included nine RCTs (total of 10,918 participants) that examined treatment with curative intent for CRC with neoadjuvant and/or adjuvant chemotherapy. We included 35 RCTs (total of 12,592 participants) that examined treatment with palliative intent for inoperable advanced or metastatic CRC with chemotherapy (31 first-line studies, two second-line studies, and two studies of first- or second-line chemotherapy). All studies included male and female participants, and no studies included participants younger than 18 years of age. Patients treated with curative intent for CRC with neoadjuvant and/or adjuvant chemotherapy • Disease-free survival (DFS): DFS did not differ between participants treated with oral versus IV fluoropyrimidines (hazard ratio (HR) 0.93, 95% confidence interval (CI) 0.87 to 1.00; seven studies, 8903 participants; moderate-quality evidence).• Overall survival (OS): OS did not differ between participants treated with oral versus IV fluoropyrimidines (HR 0.92, 95% CI 0.84 to 1.00; seven studies, 8902 participants analysed; high-quality evidence).• Grade ≥ 3 adverse events (AEs): Participants treated with oral fluoropyrimidines experienced less grade ≥ 3 neutropenia/granulocytopenia (odds ratio (OR) 0.14, 95% CI 0.11 to 0.16; seven studies, 8087 participants; moderate-quality evidence), stomatitis (OR 0.21, 95% CI 0.14 to 0.30; five studies, 4212 participants; low-quality evidence), and any grade ≥ 3 AEs (OR 0.82, 95% CI 0.74 to 0.90; five studies, 7741 participants; low-quality evidence). There was more grade ≥ 3 hand foot syndrome (OR 4.59, 95% CI 2.97 to 7.10; five studies, 5731 participants; low-quality evidence) in patients treated with oral fluoropyrimidines. There were no differences between participants treated with oral versus IV fluoropyrimidines in occurrence of grade ≥ 3 diarrhoea (OR 1.12, 95% CI 0.99 to 1.25; nine studies, 9551 participants; very low-quality evidence), febrile neutropenia (OR 0.59, 95% CI 0.18 to 1.90; four studies, 2925 participants; low-quality evidence), vomiting (OR 1.05, 95% CI 0.83 to 1.34; eight studies, 9385 participants; low-quality evidence), nausea (OR 1.21, 95% CI 0.97 to 1.51; seven studies, 9233 participants; low-quality evidence), mucositis (OR 0.64, 95% CI 0.25 to 1.62; four studies, 2233 participants; very low-quality evidence), and hyperbilirubinaemia (OR 1.67, 95% CI 0.52 to 5.38; three studies, 2757 participants; very low-quality evidence). Patients treated with palliative intent for inoperable advanced or metastatic CRC with chemotherapy • Progression-free survival (PFS): Overall, PFS was inferior in participants treated with oral versus IV fluoropyrimidines (HR 1.06, 95% CI 1.02 to 1.11; 23 studies, 9927 participants; moderate-quality evidence). Whilst PFS was worse in participants treated with oral compared with IV fluoropyrimidines when UFT/Ftorafur or eniluracil with oral 5-fluorouracil (5-FU) was used, PFS did not differ between individuals treated with oral versus IV fluoropyrimidines when capecitabine, doxifluridine, or S-1 was used.• OS: Overall, OS did not differ between participants treated with oral versus IV fluoropyrimidines (HR 1.02, 95% CI 0.99 to 1.05; 29 studies, 12,079 participants; high-quality evidence). OS was inferior in participants treated with oral versus IV fluoropyrimidines when eniluracil with oral 5-fluorouracil (5-FU) was used.• Time to progression (TTP): TTP was inferior in participants treated with oral versus IV fluoropyrimidines (HR 1.07, 95% CI 1.01 to 1.14; six studies, 1970 participants; moderate-quality evidence).• Objective response rate (ORR): ORR did not differ between participants treated with oral versus IV fluoropyrimidines (OR 0.98, 95% CI 0.90 to 1.06; 32 studies, 11,115 participants; moderate-quality evidence).• Grade ≥ 3 AEs: Participants treated with oral fluoropyrimidines experienced less grade ≥ 3 neutropenia/granulocytopenia (OR 0.17, 95% CI 0.15 to 0.18; 29 studies, 11,794 participants; low-quality evidence), febrile neutropenia (OR 0.27, 95% CI 0.21 to 0.36; 19 studies, 9407 participants; moderate-quality evidence), stomatitis (OR 0.26, 95% CI 0.20 to 0.33; 21 studies, 8718 participants; low-quality evidence), mucositis (OR 0.17, 95% CI 0.12 to 0.24; 12 studies, 4962 participants; low-quality evidence), and any grade ≥ 3 AEs (OR 0.83, 95% CI 0.74 to 0.94; 14 studies, 5436 participants; low-quality evidence). There was more grade ≥ 3 diarrhoea (OR 1.66, 95% CI 1.50 to 1.84; 30 studies, 11,997 participants; low-quality evidence) and hand foot syndrome (OR 3.92, 95% CI 2.84 to 5.43; 18 studies, 6481 participants; moderate-quality evidence) in the oral fluoropyrimidine arm. There were no differences between oral and IV fluoropyrimidine arms in terms of grade ≥ 3 vomiting (OR 1.18, 95% CI 1.00 to 1.40; 23 studies, 9528 participants; low-quality evidence), nausea (OR 1.16, 95% CI 0.99 to 1.36; 25 studies, 9796 participants; low-quality evidence), and hyperbilirubinaemia (OR 1.62, 95% CI 0.99 to 2.64; nine studies, 2699 participants; low-quality evidence).

AUTHORS' CONCLUSIONS

Results of this review should provide confidence that treatment for CRC with most of the oral fluoropyrimidines commonly used in current clinical practice is similarly efficacious to treatment with IV fluoropyrimidines. Treatment with eniluracil with oral 5-FU was associated with inferior PFS and OS among participants treated with palliative intent for CRC, and eniluracil is no longer being developed. Oral and IV fluoropyrimidines have different patterns of side effects; future research may focus on determining the basis for these differences.

Phase II study of short-course capecitabine plus oxaliplatin (XELOX) followed by maintenance capecitabine in advanced colorectal cancer: XelQuali study

PURPOSE

To evaluate the efficacy, safety and quality of life of a short course of oxaliplatin plus capecitabine (XELOX) followed by single-agent capecitabine in patients with previously untreated, inoperable, metastatic colorectal cancer.

METHODS

Patients received intravenous oxaliplatin 130 mg/m(2) on d1 plus oral capecitabine 1,000 mg/m(2) twice daily (bid) on d1-14 every 21 days for four cycles. Patients achieving stable disease (SD) or better than received capecitabine 1,250 mg/m(2) bid on d1-14 every 21 days until disease progression. The primary endpoint was progression-free survival (PFS).

RESULTS

Overall, 21/45 (47%) of patients responded to the initial XELOX chemotherapy whilst SD or better was documented in 76%. Median PFS was 6.7 (95% CI 5.7-9.6) months, and median overall survival (OS) was 20.5 (95% CI 13.1-28.1) months. In the 34 patients who then received capecitabine maintenance therapy, the median PFS was 8.1 (95% CI 6.2-11.8) months and median OS was 23.1 (95% CI 17.8-28.5) months. A marked reduction in the vast majority of all grades of adverse event occurred on switching from initial XELOX to maintenance capecitabine chemotherapy including grades 1-2 (77 vs. 47%) and grade 3 (7 vs. 3%) neuropathy, diarrhoea and lethargy.

CONCLUSIONS

Short-course XELOX followed by capecitabine maintenance therapy provides an active and well-tolerated treatment option for patients with previously untreated metastatic colorectal cancer. A median OS of more than 20 months is promising and by limiting the number of oxaliplatin infusions, this approach minimises the risk of unwanted cumulative neurotoxicity, is cheaper and more convenient for both patients and healthcare providers.

Treatment in advanced colorectal cancer: what, when and how?

Treatment of advanced colorectal cancer (CRC) increasingly requires a multidisciplinary approach and multiple treatment options add to the complexity of clinical decision-making. Recently novel targeted therapy against angiogenesis and epidermal growth factor receptor completed a plethora of phase III studies. The addition of bevacizumab to chemotherapy improved the efficacy over chemotherapy alone in both first and second line settings, although the magnitude of benefit may not be as great when a more optimal chemotherapy platform is used. Studies performed thus far did not address conclusively whether bevacizumab should be continued in subsequent lines of treatment. Anti-angiogenesis tyrosine kinase inhibitors have not shown any additional benefit over chemotherapy alone so far. Although some benefits were seen with cetuximab in all settings of treating advanced CRC, K-ras mutation status provides an important determinant of who would not benefit from such a treatment. Caution should be exercised in combining anti-angiogenesis with anti-EGFR strategy until further randomised data become available. In this review, we have focused on the implications of these trial results on the everyday management decisions of treating advanced CRC.

The role of targeted therapy in the treatment of advanced colorectal cancer

The introduction of targeted therapies in the treatment of metastatic colorectal cancer (MCRC) has resulted in significant improvements in efficacy outcomes. Both vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFR) inhibitors have proven to be valid and valuable agents in the management of MCRC. This review will focus on the role of the anti-VEGF monoclonal antibody, bevacizumab, and the anti-EGFR monoclonal antibodies, cetuximab and panitumumab, in MCRC. Special focus will be placed on clinical evidence supporting the use of these agents in various lines of treatment, and on KRAS as a marker of response in relationship to anti-EGFR inhibitors.

In vivo activity of novel capecitabine regimens alone and with bevacizumab and oxaliplatin in colorectal cancer xenograft models

Modifying the capecitabine dosing schedule from 14 days on, 7 days off (14/7) to 7 days on, 7 days off (7/7) may enable higher doses and improved antitumor efficacy in colorectal cancer xenografts. Capecitabine 14/7 (267 or 400 mg/kg) and 7/7 (467 or 700 mg/kg) schedules in doublet and triplet combinations with optimally dosed bevacizumab (5 mg/kg) and oxaliplatin (6.7 mg/kg) were studied in female athymic nude mice bearing HT29 colorectal xenografts. Additional studies of suboptimally dosed bevacizumab (2.5 mg/kg) and capecitabine 7/7 (360 mg/kg) were done in a similar Colo205 tumor xenograft model. Monotherapy and combination regimens were administered to groups of 10 animals and compared with vehicle controls. In the HT29 model, tumor growth inhibition and increase in life span (ILS) were significantly greater with capecitabine 7/7 than with 14/7 (P<0.05). The additional benefit of capecitabine 7/7 versus 14/7 was biologically significant according to National Cancer Institute criteria (>25% ILS). Adding bevacizumab to capecitabine 7/7 resulted in significantly greater survival relative to either agent alone (P<0.0001). When oxaliplatin was added, efficacy was significantly better with the triplet combination including capecitabine 7/7 (tumor growth inhibition>100% and ILS 234%) compared with 14/7 (95% and 81%, respectively). In the Colo205 model, combination therapy with capecitabine 7/7 plus bevacizumab resulted in significantly greater survival relative to either agent alone (P<0.0001). In conclusion, in athymic nude mice bearing moderately thymidine phosphorylase-expressing HT29 or Colo205 colorectal xenografts, a capecitabine 7/7 schedule permits increased drug delivery compared with traditional 14/7 regimens, greatly improving monotherapy activity without major toxicity.

A phase II study of first-line biweekly capecitabine and bevacizumab in elderly patients with metastatic colorectal cancer

PURPOSE

This phase II study was conducted to determine the efficacy and safety of capecitabine and bevacizumab in untreated elderly metastatic colorectal cancer patients.

METHODS

Patients received 1500 mg/m(2)/dose of capecitabine twice daily x 7 days and bevacizumab at 5mg/kg on day 1, in 2 week-cycles.

RESULTS

The study was closed early, due to poor accrual, after a total of 16 patients enrolled. Four patients had an objective response and 11 patients had stable disease. The median time to progression and overall survival were 9.5 and 21.2 months, respectively. The most common grade >or= 3 toxicities included diarrhea (13%) and hand and foot syndrome (25%). Three patients had an arterial thrombotic event and one patient developed a bowel perforation.

CONCLUSIONS

In this underpowered phase II study in elderly patients with metastatic colorectal cancer, capecitabine plus bevacizumab was associated with considerable clinical activity but at an increased risk of hand and foot syndrome and arterial thrombotic events.

Efficacy of oxaliplatin plus capecitabine or infusional fluorouracil/leucovorin in patients with metastatic colorectal cancer: a pooled analysis of randomized trials

PURPOSE

Six randomized phase II and III trials have investigated the role of oxaliplatin (OX) in combination with capecitabine (CAP) or infusional fluorouracil (FU) in metastatic colorectal cancer. This meta-analysis compared the efficacy of CAP/OX compared with infusional FU/OX.

PATIENTS AND METHODS

This analysis compared all published CAP/OX versus infusional FU/OX regimens. A total of 3,494 patients (FU, n = 1,737; CAP, n = 1,757) were analyzed for response rate (RR), progression-free (PFS), overall survival (OS), and toxicity.

RESULTS

The fixed-effect pooled estimate for RR showed higher RR for FU-based regimens (Odds ratio [OR] = 0.85; 95% CI, 0.74 to 0.97; P = .02) whereas the analysis of chemotherapy-only trials, excluding the bevacizumab containing NO16966 and TREE 2 trials, led to an OR of 0.74 (95% CI, 0.60 to 0.92; P = .007). However, for PFS (hazard ratio [HR] = 1.04; 95% CI, 0.96 to 1.12; P = .17) and OS (HR = 1.04; 95% CI, 0.95 to 1.12; P = .41) all models suggested similar outcome within the range of noninferiority. Grade 3/4 toxicities (thrombocytopenia-HR = 2.07, 95% CI, 1.42 to 3.03; P < .0002; diarrhea-HR = 1.34; 95% CI, 1.08 to 1.66; P < .0009; and grade 2/3 hand-foot-syndrome [HFS]-HR = 3.54; 95% CI, 2.07 to 6.05; P < .00001) were less prominent with FU-based regimens whereas neutropenia (HR = 0.15; 95% CI, 0.11 to 0.19; P < .00001) was lower in the CAP regimens.

CONCLUSION

The combination of CAP and OX resulted in lower RR, but this did not affect PFS and OS, which were similar in both treatment arms. The toxicity analysis showed the characteristic toxicity of each of the different FU schedules, with thrombocytopenia and HFS consistently more prominent in the CAP regimens.

Randomised trial comparing biweekly oxaliplatin plus oral capecitabine versus oxaliplatin plus i.v. bolus fluorouracil/leucovorin in metastatic colorectal cancer patients: results of the Southern Italy Cooperative Oncology study 0401

PURPOSE

Oxaliplatin combined with either fluorouracil/leucovorin (OXAFAFU) or capecitabine (OXXEL) has a demonstrated activity in metastatic colorectal cancer patients. We aimed at comparing these two regimens in terms of response rate (RR), safety, progression-free survival (PFS), and quality of life (QoL) of patients.

METHODS

A total of 322 patients with metastatic colorectal cancer were randomized to receive biweekly: oxaliplatin 100 mg/m(2) i.v. on day 1, capecitabine 1,000 mg/m(2) orally twice daily from day 1 to day 11 (OXXEL); or oxaliplatin 85 mg/m(2) i.v. on day 1; 6S-leucovorin 250 mg/m(2) i.v. and fluorouracil 850 mg/m(2) i.v. on day 2 (OXAFAFU).

RESULTS

Eleven complete and 42 partial responses were registered with OXXEL (RR = 34%); six complete and 48 partial responses were obtained with OXAFAFU (RR = 33%) (P = 0.999). Severe adverse events were less frequent (32 vs. 43%) with OXXEL, which also reduced the occurrence of severe neutropenia (10 vs. 27%) and febrile neutropenia (6 vs. 13%), but produced more gastric side effects (8 vs. 3%) and diarrhea (13 vs. 8%). QoL did not differ across the two arms. Median PFS was 6.6 months in the OXXEL, and 6.5 months in the OXAFAFU arm (HR = 1.12, P = 0.354). Median overall survival was 16.0 and 17.1 months (HR = 1.01, P = 0.883).

CONCLUSIONS

OXXEL and OXAFAFU regimens were equally active in metastatic colorectal cancer. The choice should be based on patient preference and on pharmacoeconomic evaluations.

Capecitabine plus oxaliplatin (XELOX) versus 5-fluorouracil/folinic acid plus oxaliplatin (FOLFOX-4) as second-line therapy in metastatic colorectal cancer: a randomized phase III noninferiority study

BACKGROUND

To demonstrate the noninferiority of capecitabine plus oxaliplatin (XELOX) versus 5-fluorouracil/folinic acid and oxaliplatin (FOLFOX-4) as second-line therapy in patients with metastatic colorectal cancer after prior irinotecan-based chemotherapy.

PATIENTS AND METHODS

A total of 627 patients were randomly assigned to receive XELOX (n = 313) or FOLFOX-4 (n = 314) following disease progression/recurrence or intolerance to irinotecan-based chemotherapy. The primary end point was progression-free survival (PFS).

RESULTS

PFS for XELOX was noninferior to FOLFOX-4 [hazard ratio (HR) = 0.97; 95% confidence interval (CI) 0.83-1.14] in the intention-to-treat (ITT) population. Median PFS was 4.7 months with XELOX versus 4.8 months with FOLFOX-4. The robustness of the primary analysis was supported by multivariate and subgroup analyses. Median overall survival in the ITT population was 11.9 months with XELOX versus 12.5 months with FOLFOX-4 (HR = 1.02; 95% CI 0.86-1.21). Treatment-related grade 3/4 adverse events occurred in 50% of XELOX- and 65% of FOLFOX-4-treated patients. Whereas grade 3/4 neutropenia (35% versus 5% with XELOX) and febrile neutropenia (4% versus < 1%) were more common with FOLFOX-4, grade 3/4 diarrhea (19% versus 5% with FOLFOX-4) and grade 3 hand-foot syndrome (4% versus < 1%) were more common with XELOX.

CONCLUSION

XELOX is noninferior to FOLFOX-4 when administered as second-line treatment in patients with metastatic colorectal cancer.

Randomized phase III study of capecitabine plus oxaliplatin compared with fluorouracil/folinic acid plus oxaliplatin as first-line therapy for metastatic colorectal cancer

PURPOSE

To evaluate whether capecitabine plus oxaliplatin (XELOX) is noninferior to fluorouracil. folinic acid, and oxaliplatin (FOLFOX-4) as first-line therapy in metastatic colorectal cancer (MCRC).

PATIENTS AND METHODS

The initial design of this trial was a randomized, two-arm, noninferiority, phase III comparison of XELOX versus FOLFOX-4. After patient accrual had begun, the trial design was amended in 2003 after bevacizumab phase III data became available. The resulting 2 x 2 factorial design randomly assigned patients to XELOX versus FOLFOX-4, and then to also receive either bevacizumab or placebo. We report here the results of the analysis of the XELOX versus FOLFOX-4 arms. The analysis of bevacizumab versus placebo with oxaliplatin-based chemotherapy is reported separately. The prespecified primary end point for the noninferiority analysis was progression-free survival.

RESULTS

The intent-to-treat population comprised 634 patients from the original two-arm portion of the study, plus an additional 1,400 patients after the start of the amended 2 x 2 design, for a total of 2,034 patients. The median PFS was 8.0 months in the pooled XELOX-containing arms versus 8.5 months in the FOLFOX-4-containing arms (hazard ratio [HR], 1.04; 97.5% CI, 0.93 to 1.16). The median overall survival was 19.8 months with XELOX versus 19.6 months with FOLFOX-4 (HR, 0.99; 97.5% CI, 0.88 to 1.12). FOLFOX-4 was associated with more grade 3/4 neutropenia/granulocytopenia and febrile neutropenia than XELOX, and XELOX with more grade 3 diarrhea and grade 3 hand-foot syndrome than FOLFOX-4.

CONCLUSION

XELOX is noninferior to FOLFOX-4 as a first-line treatment for MCRC, and may be considered as a routine treatment option for appropriate patients.

Phase III study of capecitabine plus oxaliplatin compared with fluorouracil and leucovorin plus oxaliplatin in metastatic colorectal cancer: a final report of the AIO Colorectal Study Group

PURPOSE

To compare the use of capecitabine plus oxaliplatin (CAPOX) with infusional fluorouracil (FU)/folinic acid plus oxaliplatin (FUFOX) as first-line therapy for patients with metastatic colorectal cancer (MCRC).

PATIENTS AND METHODS

A total of 474 patients with MCRC received either CAPOX (capecitabine 1,000 mg/m2 bid, days 1 to 14 plus oxaliplatin 70 mg/m2 days 1 and 8, repeated every 22 days) ) or FUFOX (oxaliplatin 50 mg/m2 followed by leucovorin 500 mg/m2 plus FU 2,000 mg/m2 as a 22-hour infusion days 1, 8, 15, and 22, repeated every 36 days). The primary end point was progression-free survival (PFS). Secondary end points were response rate (RR), overall survival (OS), time to treatment failure, and toxicity. The study was designed to determine noninferiority for the CAPOX regimen.

RESULTS

Median PFS was 7.1 months in the CAPOX arm and 8.0 months in the FUFOX arm (hazard ratio [HR], 1.17; 95% CI, 0.96 to 1.43; P = .117). Median OS was 16.8 months (CAPOX) and 18.8 months (FUFOX; HR, 1.12; 95% CI, 0.92 to 1.38; P = .26). Overall RRs were 48% for CAPOX (95% CI, 41% to 54%) and 54% for FUFOX (95% CI, 47% to 60%). Both regimens were generally well tolerated, although there was a significantly higher incidence of grade 2/3 hand-foot syndrome (HFS) in the CAPOX arm (P = .028).

CONCLUSION

CAPOX resulted in a slightly inferior efficacy than FUFOX. With respect to PFS, the best estimate of the HR of 1.17 was within the prespecified equivalence range. However, a relevant inferiority cannot be excluded. Both regimens were generally well tolerated but there was a significantly higher rate of grade 2/3 HFS in the CAPOX arm.