Capecitabine plus oxaliplatin vs fluorouracil plus oxaliplatin as first line treatment for metastatic colorectal caner - meta-analysis of six randomized trials

Dihydropyrimidine Dehydrogenase Levels in Colorectal Cancer Cells Treated with a Combination of Heat Shock Protein 90 Inhibitor and Oxaliplatin or Capecitabine

Purpose: Dihydropyrimidine dehydrogenase (DPD) is the principal enzyme in the catabolism of fluoropyrimidine drugs including capecitabine. A recent report has suggested that oxaliplatin chemotherapy is associated with elevated DPD levels and chemoresistance pattern. As a newly developed chemotherapeutic agent, 17-allyloamino-17-demethoxy-geldanamycin (17-AAG) can be effective in combination therapy with oxaliplatin and capecitabine in colorectal cancer (CRC). DPD expression level can be a predictive factor in oxaliplatin and capecitabine-based chemotherapy. We evaluated DPD in mRNA and protein levels with new treatments: 17-AAG in combination with oxaliplatin and capecitabine in HT-29 and HCT-116 cell lines. Methods: Drug sensitivity was determined by the water-soluble tetrazolium-1 assay in a previous survey. Then, we evaluated the expression levels of DPD and its relationship with the chemotherapy response in capecitabine, oxaliplatin, and 17-AAG treated cases in single and combination cases in two panels of CRC cell lines. DPD gene and protein expression levels were determined by real-time polymerase chain reaction and western blotting assay, respectively. Results: DPD gene expression levels insignificantly increased in single-treated cases versus untreated controls in both cell lines versus controls. Then, the capecitabine and oxaliplatin were added in double combinations, where DPD gene and protein expression increased in combination cases compared to pre-chemotherapy and single drug treatments. Conclusion: The elevated levels of cytotoxicity in more effective combinations could be related to a different mechanism apart from DPD mediating effects or high DPD level in the remaining resistance cells (drug-insensitive cells), which should be investigated in subsequent studies.

Capecitabine Versus Continuous Infusion Fluorouracil for the Treatment of Advanced or Metastatic Colorectal Cancer: a Meta-analysis

OPINION STATEMENT

Nowadays, systemic chemotherapy with intravenous (IV) 5-fluorouracil (5-FU) remains the most commonly prescribed treatment for metastatic colorectal cancers (CRC), in combination with other cytotoxic drugs. 5-FU can be administered through a bolus injection or continuous infusion (cIV), with the latter becoming the preferred administration method and standard of care in recent years. Oral fluoropyrimidines were developed to overcome challenges associated with the IV administration of 5-FU, among which capecitabine has become the most widely used one. However, although capecitabine and other oral fluoropyrimidine-based regimens are more convenient to administer, their efficacy and safety in comparison with IV 5-FU are not well understood. Results from recent randomized controlled trials, observational studies, and meta-analyses have been inconsistent. Safety, in particular, remains controversial. Our review, a first comprehensive meta-analysis comparing the efficacy and safety of cIV 5-FU with capecitabine, the two most widely used fluorouracil modalities in CRC, showed that cIV 5-FU-based regimens are associated with greater response rates compared with capecitabine-based regimens, with no difference in progression-free survival, time to treatment failure, overall survival, or disease-free survival between the two. Furthermore, cIV 5-FU-based regimens showed an improved safety profile compared with capecitabine-based regimens. Our findings suggest that cIV 5-FU remains a more effective and safer modality of fluorouracil administration than capecitabine, thus providing supporting evidence to guide clinical practice in the management of colorectal cancer.

Cost-Effectiveness of Cetuximab as First-line Treatment for Metastatic Colorectal Cancer in the United States

PURPOSE

We conducted a cost-effectiveness analysis incorporating recent phase III clinical trial (FIRE-3) data to evaluate clinical and economic tradeoffs associated with first-line treatments of KRAS wild-type (WT) metastatic colorectal cancer (mCRC).

MATERIALS AND METHODS

A cost-effectiveness model was developed using FIRE-3 data to project survival and lifetime costs of FOLFIRI plus either cetuximab or bevacizumab. Hypothetical KRAS-WT mCRC patients initiated first-line treatment and could experience adverse events, disease progression warranting second-line treatment, or clinical response and hepatic metastasectomy. Model inputs were derived from FIRE-3 and published literature. Incremental cost-effectiveness ratios (ICERs) were reported as US$ per life year (LY) and quality-adjusted life year (QALY). Scenario analyses considered patients with extended RAS mutations and CALGB/SWOG 80405 data; 1-way and probabilistic sensitivity analyses were conducted.

RESULTS

Compared with bevacizumab, KRAS-WT patients receiving first-line cetuximab gained 5.7 months of life at a cost of $46,266, for an ICER of $97,223/LY ($122,610/QALY). For extended RAS-WT patients, the ICER was $77,339/LY ($99,584/QALY). Cetuximab treatment was cost-effective 80.3% of the time, given a willingness-to-pay threshold of $150,000/LY. Results were sensitive to changes in survival, treatment duration, and product costs.

CONCLUSIONS

Our analysis of FIRE-3 data suggests that first-line treatment with cetuximab and FOLFIRI in KRAS (and extended RAS) WT mCRC patients may improve health outcomes and use financial resources more efficiently than bevacizumab and FOLFIRI. This information, in combination with other studies investigating comparative effectiveness of first-line options, can be useful to clinicians, payers, and policymakers in making treatment and resource allocation decisions for mCRC patients.

Cytotoxic effects of the newly-developed chemotherapeutic agents 17-AAG in combination with oxaliplatin and capecitabine in colorectal cancer cell lines

The use of heat shock protein 90 inhibitors like 17-allylamino-17-demethoxy-geldanamycin (17-AAG) has been recently introduced as an attractive anticancer therapy. It has been shown that 17-AAG may potentiate the inhibitory effects of some classical anticolorectal cancer (CRC) agents. In this study, two panels of colorectal carcinoma cell lines were used to evaluate the effects of 17-AAG in combination with capecitabine and oxaliplatin as double and triple combination therapies on the proliferation of CRC cell lines. HT-29 and all HCT-116 cell lines were seeded in culture media in the presence of different doses of the mentioned drugs in single, double, and triple combinations. Water-soluble tetrazolium-1 (WST-1) assay was used to investigate cell proliferation 24 h after treatments. Then, dose-response curves were plotted using WST-1outputs, and IC₅₀ values were determined. For double and triple combinations respectively 0.5 × IC₅₀ and 0.25 × IC₅₀ were used. Data was analyzed with the software CompuSyn. Drug interactions were analyzed using Chou-Talalay method to calculate the combination index (CI).The data revealed that 17-AAG shows a potent synergistic interaction (CI < 1) with oxaliplatin and capecitabine in double combinations (0.5 × IC₅₀) in both cell lines. In the case of triple combinations, the findings showed an antagonistic interaction (CI > 1) in HT-29 and a synergistic effect (CI < 1) in HCT-116 (0.25 × IC₅₀) cell lines. It was concluded that double combinations of 17-AAG with oxaliplatin or capecitabine might be effective against HCT-116 and HT-29 cell lines. However, in triple combinations, positive results were seen only against HCT-116. Further investigation is suggested to confirm the effectiveness of these combinations in clinical trials.

XELOX vs. FOLFOX in metastatic colorectal cancer: An updated meta-analysis

This meta-analysis aims to evaluate chemotherapy with XELOX (capecitabine plus oxaliplatin) versus FOLFOX (fluorouracil plus oxaliplatin) as a treatment for metastatic colorectal cancer (mCRC) in terms of efficacy and safety. Only randomized controlled trials (RCTs) comparing XELOX versus FOLFOX were included. A total of 4,363 patients from eight RCTs were available for analysis. Pooled analysis revealed that there were no statistical differences between both arms in OS, and ORR. XELOX arm had a higher incidence of thrombocytopenia, hand-foot syndrome, and diarrhea, whereas neutropenia had a higher incidence in the FOLFOX group. For mCRC, the effect of XELOX is similar to FOLFOX.

Incidence and relative risk of grade 3 and 4 diarrhoea in patients treated with capecitabine or 5-fluorouracil: a meta-analysis of published trials

AIM

Capecitabine is an oral fluoropyrimidine that can effectively replace infusional 5-fluorouracil (5-FU) for treatment of colorectal, gastric and breast cancer. This study aims to analyze the incidence and the relative risk of grade 3 and 4 diarrhoea in patients treated with capecitabine or 5-FU in randomized clinical trials (RCTs).

METHODS

MEDLINE and Cochrane Library were reviewed for RCTs that compared capecitabine with 5-FU for treatment of solid malignancies. The incidence and relative risk (RR) of grade 3/4 diarrhoea were estimated for each arm in the overall population and in colorectal cancer (CRC) patients

RESULTS

Twenty-three studies and 15,761 patients were included. Among these 8303 and 7458 patients received capecitabine or 5-FU based therapies, respectively. In the overall populations severe diarrhoea was reported in 16.6% (95% CI 15.8, 17.4) and in 12.7% (95% CI 11.9, 13.4) of patients treated with capecitabine or 5-FU-based therapies, respectively. The RR was 1.39 (95% CI 1.14, 1.69, P = 0.0010). In 14,899 CRC patients, the incidence of severe diarrhoea was 17.0% (95% CI 16.2, 17.9) and 12.9% (95% CI 12.1, 13.7), respectively, with a RR of 1.46 (95% CI 1.18, 1.81, P < 0.0001). In CRC patients treated with combined chemotherapy, the RR was 1.40 (95% CI 1.07, 1.82; P = 0.01) for patients receiving oxaliplatin and 2.35 (95% CI 1.76, 3.13; P < 0.0001) for patients receiving irinotecan.

CONCLUSIONS

Treatment with capecitabine is characterized by an increased risk of severe diarrhoea, mainly in patients affected by CRC and treated with polichemotherapy. Combination treatment with irinotecan doubles the risk over 5-FU.

Seeing the forest through the trees: a systematic review of the safety and efficacy of combination chemotherapies used in the treatment of metastatic colorectal cancer

Combinations of fluoropyrimidines with oxaliplatin or irinotecan plus a biologic agent are standard treatments for metastatic colorectal cancer (mCRC). Recent approvals of first-line cetuximab, second-line ziv-aflibercept, and regorafenib as salvage therapy have increased the complexity of the treatment armamentarium. To define optimal regimens, we systematically reviewed combination chemotherapy trials (N=83). Descriptive analyses focusing on fluoropyrimidine formulation, oxaliplatin vs irinotecan combinations, and compatibility with biologics indicated the following: infusional 5-fluorouracil (5-FU) yielded better efficacy and safety than bolus 5-FU. Capecitabine had similar outcomes and better safety than 5-FU with oxaliplatin but not irinotecan. First-line oxaliplatin and irinotecan appeared equivalent. Antiangiogenics, such as bevacizumab and ziv-aflibercept, and epidermal growth factor receptor-targeted monoclonal antibodies cetuximab and panitumumab further improved efficacy. The treatment landscape for mCRC has become complex, and we are approaching individualized therapy based on predictive factors, including KRAS mutational status. Appropriate administration of chemotherapy/biologic combinations is critical.

Combination therapies with oxaliplatin and oral capecitabine or intravenous 5-FU show similar toxicity profiles in gastrointestinal carcinoma patients if hand-food syndrome prophylaxis is performed continuously

The use of anticancer drugs in palliative settings is often limited by their severe toxic effects. In gastrointestinal carcinomas the 5-fluorouracil-based palliative regimen FOLFOX-4 is often preferred to the equally effective, but more convenient oral capecitabine-based regimen XELOX. This preference is mainly based on the fact that the highly effective oral agent capecitabine induces hand-foot syndrome (HFS). In this study, we investigated whether the continuous administration of skin prophylaxis (10% urea, panthenol, bisabolol, vitamin A, C and E) is capable of protecting against capecitabine-induced HFS and allowing a more convenient oral therapeutic option. In this retrospective analysis, the toxicity profiles, according to NCI CTCAE 3.0 criteria, of 54 patients with gastrointestinal cancer who received either XELOX (34 patients) or FOLFOX-4 (20 patients) were compared using Fisher tests. The treatment protocols that were compared, herein, did not differ significantly in the majority of the analyzed items, with the exception of increased nausea (XELOX-70), fatigue (XELOX-130) and tumor pain (XELOX-70 and XELOX-130). No significant differences were observed among the various groups with regard to emesis, diarrhea, mucositis, exanthema, alopecia, loss of weight and the incidence of infections. In particular, no significant differences in toxicity levels occurred in terms of dose, and HFS was limited if skin prophylaxis was performed continuously. XELOX-based palliative regimens provide an equally effective and comparably toxic therapeutic alternative to FOLFOX-4 if HFS prophylaxis is performed continuously. Since the oral administration of capecitabine is a more convenient method of application, it provides patients with a quality of life-preserving therapeutic alternative.

Does anti-EGFR therapy improve outcome in advanced colorectal cancer? A systematic review and meta-analysis

BACKGROUND

Randomised controlled trials (RCTs) of anti-EGFR monoclonal antibodies (MAb) in patients with advanced colorectal cancer (aCRC) have reported conflicting results.

METHODS

A systematic review of RCTs comparing standard treatments±anti-EGFR MAbs was conducted. Hazard ratios (HR) for progression-free (PFS) and overall survival (OS) were derived for patients with wild-type (WT) and mutant KRAS. Prespecified analyses were conducted for line of treatment, MAb used, chemotherapy regimen, and choice of fluouropyrimidine. Trials using bevacizumab on both arms were included in a sensitivity analysis.

RESULTS

Fourteen eligible RCTs were identified, with results by KRAS status available for ten RCTs. For third line treatment, the effect of anti-EGFR MAbs depended on KRAS status (interaction p<0.00001), with a PFS benefit for patients with WT KRAS only (HR=0.43, 95% CI 0.35-0.52, p<0.00001). For first and second line treatment, the effect also appeared to depend on KRAS status (interaction p=0.0003), again with the PFS benefit only for patients with WT KRAS (HR=0.83, 95% CI 0.76-0.90, p<0.0001). Differences between trial results (heterogeneity p=0.02, I(2)=62%) were best explained by the fluouropyrimidine used, with PFS benefits confined to trials combining MAbs alongside 5FU-based chemotherapy (HR=0.77, 95% CI 0.70-0.85, p<0.00001). There was no evidence of a PFS benefit when MAbs were given with bevacizumab.

CONCLUSIONS

For aCRC patients with WT KRAS, there are clear benefits of anti-EGFR MAbs in the third line and in the first and second line, when used alongside infusional 5FU-based regimens. However, there is no benefit for patients with KRAS mutations.

Capecitabine-based chemotherapy for metastatic colorectal cancer

PURPOSE

Metastatic colorectal cancer (MCRC) remains a significant public health concern. The objectives of present study are to investigate the efficacy and safety profile of capecitabine-based chemotherapy in the treatment of MCRC.

MATERIALS AND METHODS

We performed a computerized search using combinations of the following keywords: "metastatic colorectal cancer," "Xeloda," "chemotherapy," "capecitabine," or "5-fluorouracil."

RESULTS

Treatment with capecitabine chemotherapy was associated with a significantly prolonged progression-free survival (WMD = 1.24; 95% CI, 0.04-2.44; P = 0.04), whereas overall survival was not statistically significant (WMD [random] = 0.29; P = 0.75). Patients in both capecitabine and 5-fluorouracil groups had equal 1-, 2-, and 3-year survival (OR = 0.82, 95% CI: 0.59-1.12, P = 0.21; OR = 0.84, 95% CI: 0.61-1.15, P = 0.27; OR = 1.26, 95% CI: 0.78-2.05, P = 0.34; respectively). The analysis also demonstrates that the response rate of capecitabine-based chemotherapy was comparable to 5-fluorouracil-based chemotherapy (OR = 1.02, 95% CI, 0.90-1.14; P = 0.80). When comparing single-agent capecitabine against 5-fluorouracil/leucovorin, our results showed an overall OR of 1.56 (95% CI, 1.16-2.09) in favor of the capecitabine arm. When toxicity was evaluated, a statistically significant benefit with capecitabine-based therapy was seen, especially for grade 3/4 neutropenia (OR, 0.80; 95% CI, 0.71-0.91; P = 0.00005).

CONCLUSIONS

Capecitabine-based chemotherapy demonstrated a significantly superior progression-free survival, equivalent overall survival, and comparable response rate with 5-fluorouracil-based chemotherapy. These observations support the use of capecitabine-based chemotherapy in the treatment of MCRC as a first-line or as a neoadjuvant modality.