Capecitabine (Xeloda) improves medical resource use compared with 5-fluorouracil plus leucovorin in a phase III trial conducted in patients with advanced colorectal carcinoma

Standard therapy for advanced or metastatic colorectal cancer consists of 5-fluorouracil plus leucovorin (5-FU/LV) administered intravenously (i.v.). Capecitabine (Xeloda), an oral fluoropyrimidine carbamate which is preferentially activated by thymidine phosphorylase in tumour cells, mimics continuous 5-FU and is a recently developed alternative to i.v. 5-FU/LV. The choice of oral rather than intravenous treatment may affect medical resource use because the two regimens do not require the same intensity of medical intervention for drug administration, and have different toxicity profiles. Here we examine medical resource use in the first-line treatment of colorectal cancer patients with capecitabine compared with those receiving the Mayo Clinic regimen of 5-FU/LV. In a prospective, randomised phase III clinical trial, 602 patients with advanced or metastatic colorectal cancer recruited from 59 centres worldwide were randomised to treatment with either capecitabine or the Mayo regimen of 5-FU/LV. In addition to clinical efficacy and safety endpoints, data were collected on hospital visits required for drug administration, hospital admissions, and drugs and unscheduled consultations with physicians required for the treatment of adverse events. Capecitabine treatment in comparison to 5-FU/LV in advanced colorectal carcinoma resulted in superior response rates (26.6% versus 17.9%, P=0.013) and improved safety including less stomatitis and myelosuppression. Capecitabine patients required substantially fewer hospital visits for drug administration than 5-FU/LV patients. Medical resource use analysis showed that patients treated with capecitabine spent fewer days in hospital for the management of treatment related adverse events than did patients treated with 5-FU/LV. In addition, capecitabine reduced the requirement for expensive drugs, in particular antimicrobials fluconazole and 5-HT3-antagonists to manage adverse events. As anticipated with an oral home-based therapy patients receiving capecitabine needed more frequent unscheduled home, day care, office and telephone consultations with physicians. In the light of clinical results from the phase III trial demonstrating increased efficacy in terms of response rate, equivalent time to progression (TTP) and survival (OS), and a superior safety profile, the results from this medical resource assessment indicate that capecitabine treatment of colorectal cancer patients results in a substantial resource use saving relative to the Mayo Clinic regimen of 5-FU/LV. This benefit is derived principally from the avoidance of hospital visits for i.v. drug administration, less expensive drug therapy for the treatment of toxic side-effects, and fewer treatment-related hospitalisations required during the course of therapy for adverse drug reactions in comparison to patients treated with 5-FU/LV.     

Oral capecitabine: bridging the Atlantic divide in colon cancer treatment

5-Fluorouracil (5-FU) plus leucovorin (LV) has been the mainstay of treatment for colorectal cancer (CRC), with infused schedules more widely adopted in Europe and bolus schedules preferred in North America. However, the effective, oral fluoropyrimidine capecitabine is increasingly replacing intravenous (IV) 5-FU/LV on both sides of the Atlantic. Capecitabine generates 5-FU preferentially in tumor and is a well-established, first-line treatment for metastatic CRC. In this setting, capecitabine achieves a superior response rate, at least equivalent time to disease progression (TTP) and overall survival, and favorable safety compared with bolus 5-FU/LV. The benefits of capecitabine have been transfered into the adjuvant setting. Recent data from a large, international, randomized trial (Xeloda Adjuvant Chemotherapy Trial [X-ACT]) confirm that capecitabine (Xeloda, Roche Laboratories, Nutley, NJ) achieves favorable safety versus 5-FU/LV (Mayo Clinic regimen) and is at least as effective as IV 5-FU/LV in the adjuvant treatment of patients with resected stage III colon cancer. Capecitabine is also an effective and well-tolerated combination partner for oxaliplatin (XELOX) and irinotecan (XELIRI), achieving high efficacy with a good safety profile. An extensive phase III clinical trial program is further establishing the potential of the simplified capecitabine combinations to improve outcomes and unify treatment practices in the metastatic and adjuvant settings. New combinations with novel agents such as capecitabine/oxaliplatin plus erlotinib or bevacizumab are currently under investigation. Capecitabine has also shown promising activity and good tolerability in combination with radiotherapy in rectal cancer.     

Oral capecitabine as an alternative to i.v. 5-fluorouracil-based adjuvant therapy for colon cancer: safety results of a randomized, phase III trial.

BACKGROUND: Oral capecitabine achieves a superior response rate with an improved safety profile compared with bolus 5-fluorouracil-leucovorin (5-FU/LV) as first-line treatment for patients with metastatic colorectal cancer. We report here the results of a large phase III trial investigating adjuvant oral capecitabine compared with 5-FU/LV (Mayo Clinic regimen) in Dukes' C colon cancer. PATIENTS AND METHODS: Patients aged 18-75 years with resected Dukes' C colon carcinoma were randomized to receive 24 weeks of treatment with either oral capecitabine 1250 mg/m(2) twice daily, days 1-14 every 21 days (n = 993), or i.v. bolus 5-FU 425 mg/m(2) with i.v. leucovorin 20 mg/m(2) on days 1-5, repeated every 28 days (n = 974). RESULTS: Patients receiving capecitabine experienced significantly (P <0.001) less diarrhea, stomatitis, nausea/vomiting, alopecia and neutropenia, but more hand-foot syndrome than those receiving 5-FU/LV. Fewer patients receiving capecitabine experienced grade 3 or 4 neutropenia, febrile neutropenia/sepsis and stomatitis (P <0.001), although more experienced grade 3 hand-foot syndrome than those treated with 5-FU/LV (P <0.001). Capecitabine demonstrates a similar, favorable safety profile in patients aged <65 years or > or = 65 years old. CONCLUSIONS: Based on its improved safety profile, capecitabine has the potential to replace 5-FU/LV as standard adjuvant treatment for patients with colon cancer. Efficacy results are expected to be available in Keywords: Adjuvant treatment, capecitabine, chemotherapy, colorectal cancer     

New options for outpatient chemotherapy--the role of oral fluoropyrimidines.

For several decades fluoropyrimidines, especially 5-fluorouracil (5-FU), have played a role in standard chemotherapy regimens for a range of solid tumours, including breast and colorectal cancers. In recent years, schedule modification and biomodulation have achieved improved efficacy and tolerability. However, the complications arising from infused intravenous administration are well-recognized and there is an unmet medical need for oral agents with improved efficacy and tolerability, offering more convenient outpatient therapy.Several oral fluoropyrimidines are in development, including capecitabine, UFT (uracil plus tegafur), S-1 and eniluracil. As yet, only UFT/leucovorin and capecitabine have been evaluated in randomized phase III clinical trials in metastatic colorectal cancer. Both have demonstrated safety benefits and equivalent survival compared with the Mayo Clinic regimen, and capecitabine has demonstrated a significantly superior response rate. Time to disease progression was equivalent to the Mayo Clinic regimen with capecitabine, but inferior with UFT/leucovorin. Capecitabine is also effective in patients with taxoid-pretreated metastatic breast cancer, a population which previously had no established treatment options.Both capecitabine and UFT/leucovorin are being evaluated in combination with irinotecan and oxaliplatin in colorectal cancer, and vinorelbine and docetaxel/paclitaxel in breast cancer. In the future, these more convenient, oral fluoropyrimidines may replace intravenous 5-FU in the treatment of breast and colorectal cancer.     

A randomised cross-over trial comparing patient preference for oral capecitabine and 5-fluorouracil/leucovorin regimens in patients with advanced colorectal cancer.

BACKGROUND: Traditionally, metastatic colorectal cancer (MCRC) has been treated with intravenous (i.v.) 5-fluorouracil/leucovorin (5-FU/LV). The tumour-activated, oral fluoropyrimidine capecitabine demonstrates superior activity and favourable safety compared with the Mayo regimen, while potentially avoiding the complications and inconvenience associated with i.v. regimens. PATIENTS AND METHODS: Ninety-seven patients with previously untreated advanced/MCRC were randomised to receive capecitabine followed by i.v. 5-FU/LV [Mayo Clinic, in-patient de Gramont (IPdG) or out-patient modified de Gramont (OPdG) regimens], or i.v. 5-FU/LV followed by capecitabine. RESULTS: Before treatment, of those patients for whom a preference was recorded, almost all (95%) preferred oral treatment (consistent across all treatment groups) and the majority retained this preference after treatment (64% overall; 86%, 63% and 50% in the Mayo, IPdG and OPdG groups, respectively). Following treatment, the principal reasons for oral treatment preference were increased convenience, home-based administration and tablet formulation. Treatment satisfaction was significantly higher with capecitabine compared with Mayo (P<0.05) and with OPdG compared with capecitabine (P<0.05). Quality of life (QoL) was largely constant across the regimens, although it appeared better with OPdG than capecitabine (P<0.05). Grade 3/4 adverse events were uncommon in all arms. CONCLUSIONS: This study confirmed that the majority of patients with MCRC prefer oral to i.v. therapy, although the OPdG regimen appears to be the most popular i.v. option. Capecitabine clearly represents an effective, well-tolerated oral alternative to i.v. 5-FU/LV.     

Oral capecitabine vs intravenous 5-fluorouracil and leucovorin: integrated efficacy data and novel analyses from two large, randomised, phase III trials

This study evaluates the efficacy of capecitabine using data from a large, well-characterised population of patients with metastatic colorectal cancer (mCRC) treated in two identically designed phase III studies. A total of 1207 patients with previously untreated mCRC were randomised to either oral capecitabine (1250 mg m(-2) twice daily, days 1-14 every 21 days; n=603) or intravenous (i.v.) bolus 5-fluorouracil/leucovorin (5-FU/LV; Mayo Clinic regimen; n=604). Capecitabine demonstrated a statistically significant superior response rate compared with 5-FU/LV (26 vs 17%; P<0.0002). Subgroup analysis demonstrated that capecitabine consistently resulted in superior response rates (P<0.05), even in patient subgroups with poor prognostic indicators. The median time to response and duration of response were similar and time to progression (TTP) was equivalent in the two arms (hazard ratio (HR) 0.997, 95% confidence interval (CI) 0.885-1.123, P=0.95; median 4.6 vs 4.7 months with capecitabine and 5-FU/LV, respectively). Multivariate Cox regression analysis identified younger age, liver metastases, multiple metastases and poor Karnofsky Performance Status as independent prognostic indicators for poor TTP. Overall survival was equivalent in the two arms (HR 0.95, 95% CI 0.84-1.06, P=0.48; median 12.9 vs 12.8 months, respectively). Capecitabine results in superior response rate, equivalent TTP and overall survival, an improved safety profile and improved convenience compared with i.v. 5-FU/LV as first-line treatment for MCRC. For patients in whom fluoropyrimidine monotherapy is indicated, capecitabine should be strongly considered. Following encouraging results from phase I and II trials, randomised trials are evaluating capecitabine in combination with irinotecan, oxaliplatin and radiotherapy. Capecitabine is a suitable replacement for i.v. 5-FU as the backbone of colorectal cancer therapy.     

Comparison of oral capecitabine versus intravenous fluorouracil plus leucovorin as first-line treatment in 605 patients with metastatic colorectal cancer: results of a randomized phase III study.

PURPOSE: To compare the response rate, efficacy parameters, and toxicity profile of oral capecitabine with bolus intravenous (IV) fluorouracil plus leucovorin (5-FU/LV) as first-line treatment in patients with metastatic colorectal cancer. PATIENTS AND METHODS: We prospectively randomized 605 patients to treatment with oral capecitabine for 14 days every 3 weeks or 5-FU/LV by rapid IV injection daily for 5 days in 4-week cycles. RESULTS: The overall objective tumor response rate among all randomized patients was significantly higher in the capecitabine group (24.8%) than in the 5-FU/LV group (15.5%; P =.005). In the capecitabine and 5-FU/LV groups, median times to disease progression were 4.3 and 4.7 months (log-rank P =.72), median times to treatment failure were 4.1 and 3.1 months (P =.19), and median overall survival times were 12.5 and 13.3 months (P =.974), respectively. Capecitabine, compared with bolus 5-FU/LV treatment, produced a significantly lower incidence (P <.0002) of diarrhea, stomatitis, nausea, and alopecia. Patients treated with capecitabine also displayed lower incidences of grade 3/4 stomatitis and grade 3/4 neutropenia (P <.0001) leading to significantly less neutropenic fever/sepsis. Grade 3 hand-foot syndrome (P <.00001) and grade 3/4 hyperbilirubinemia were the only toxicities more frequently associated with capecitabine than with 5-FU/LV treatment. CONCLUSION: Oral capecitabine was more active than 5-FU/LV in the induction of objective tumor responses. Time to disease progression and survival were at least equivalent for capecitabine compared with the 5-FU/LV arm. Capecitabine also demonstrated clinically meaningful benefits over bolus 5-FU/LV in terms of tolerability.     

Capecitabine for locally advanced and metastatic colorectal cancer: A review

Capecitabine (Xeloda^®) is an oral fluoropyrimidine which is produced as a pro-drug of fluorouracil, and shows improved tolerability and intratumor drug concentrations following its tumor-specific conversion to the active drug. We have searched the Pubmed and Cochrane databases from 1980 to 2009 with the purpose of reviewing all available information on Capecitabine, focusing on its clinical effectiveness against colorectal cancer. Special attention has been paid to trials that compared Capecitabine with standard folinic acid (leucovorin, LV)-modulated intravenous 5-fluorouracil (5-FU) bolus regimens in patients with metastatic colorectal cancer. Moreover the efficacy of Capecitabine on metastatic colorectal cancer, either alone or in various combinations with other active drugs such as Irinotecan and Oxaliplatin was also assessed. Finally, neoadjuvant therapy consisting of Capecitabine plus radiation therapy, for locally advanced rectal cancer was analysed. This combination of chemotherapy and radiotherapy has a special role in tumor down staging and in sphincter preservation for lower rectal tumors. Comparative trials have shown that Capecitabine is at least equivalent to the standard LV-5-FU combination in relation to progression-free and overall survival whilst showing a better tolerability profile with a much lower incidence of stomatitis. It is now known that Capecitabine can be combined with other active drugs such as Irinotecan and Oxaliplatin. The combination of Oxaliplatin with Capecitabine represents a new standard of care for metastatic colorectal cancer. Combinating the Capecitabine-Oxaliplatin regimen with promising new biological drugs such as Bevacizumab seems to give a realistic prospect of further improvement in time to progression of metastatic disease. Moreover, preoperative chemo-radiation using oral capecitabine is better tolerated than bolus 5-FU and is more effective in the promotion of both down-staging and sphincter preservation in patients with locally advanced rectal cancer. Finally, the outcomes of recently published trials suggest that capecitabine seems to be more cost effective than other standard treatments for the management of patients with colorectal cancer.     

Capecitabine plus oxaliplatin for the treatment of colorectal cancer

Based on improved safety and efficacy results, advanced colorectal cancer (CRC) treatment has recently shifted from intravenous bolus 5-fluorouracil (5-FU) monotherapy to standard combinations of prolonged intravenous 5-FU infusion with either oxaliplatin (FOLFOX) or irinotecan (FOLFIRI). Capecitabine, a rationally designed oral fluoropyrimidine that is converted into 5-FU preferentially at the tumor site, could replace infusional 5-FU as the mainstay of combined chemotherapy treatment for metastatic CRC. Evidently, oral medication obviates the drawbacks of prolonged intravenous infusion. The combination of capecitabine and oxaliplatin is especially attractive owing to its favorable tolerability profile, good activity and convenient administration schedule. Phase III trials comparing capecitabine/oxaliplatin with infusional regimens of 5-FU +/- LV and oxaliplatin in advanced CRC show similar toxicity and efficacy outcomes with both regimens. Capecitabine has the potential to replace 5-FU/LV as the optimal combination partner for oxaliplatin at a higher cost. Capecitabine and oxaliplatin concomitantly with radiation therapy has been evaluated before surgery in rectal cancer treatment. The combination of capecitabine and oxaliplatin, with or without bevacizumab, a monoclonal antibody blocking VEGF, is also being evaluated in early stage colon cancer.     

Capecitabine--a review of its antitumor activity and toxicity in clinical studies

Capecitabine is a novel fluoropyrimidine carbamate, orally administered and rationally designed to undergo tumor-selective activation. Some studies have been proven it to be safe for outpatient treatment and to have significant antitumor activity in colorectal and breast cancer patients. Randomized trials of patients with advanced colorectal cancer using capecitabine versus Leucovorin (LV).5-FU were studied in two groups. Capecitabine results in both a higher response rate and a more favorable toxicity profile than LV.5-FU. In women aged 55 years or more with breast cancer, capecitabine showed at least comparable efficacy to CMF combination therapy. Capecitabine offers a new effective oral treatment option as a single agent for patients with advanced colorectal or breast cancer.     

Progress in chemotherapy for colorectal cancer

Among colorectal cancer patients with recurrent or metastatic sites, survival was significantly prolonged for a group undergoing LV/5-FU therapy based on biochemical modulation compared with a group receiving no chemotherapy (best supportive care). LV/5-FU combination therapy is recognized as the standard therapy for colorectal cancer, but recently LV/5-FU plus oxaliplatin and LV/5-FU plus CPT-11 have appeared to be more effective than LV/5-FU in some randomized studies. Capecitabine, UFT/LV and S-1 are new oral drugs that are at least comparable to LV/5-FU in antitumor activity, but superior in tolerability, which benefits the patients' quality of life, especially elderly patients with colorectal cancer. Clinical combination studies using CDDP or CPT-11 with these oral drugs are now being performed. Much is expected of these drugs.     

Capecitabine versus 5-fluorouracil in colorectal cancer: where are we now?

Fluorouracil (5-FU) remains the most widely used agent for colorectal cancer. Capecitabine is a rationally designed 5-FU pro-drug developed to mimic the continuous infusion of 5-FU while avoiding complications and inconvenience of intravenous administration. Capecitabine is absorbed intact from the gastrointestinal tract, converted enzymatically to active 5-FU, and released directly into the tumor. Capecitabine’s efficacy and safety are shown in multiple phase III trials across different disease stages and therapy lines. Three randomized phase III trials demonstrated the equivalence of capecitabine plus oxaliplatin (XELOX) versus 5-FU/leucovorin (LV)/oxaliplatin (FOLFOX). The safety of capecitabine compared with 5-FU depends on the regimen of 5-FU used. The adverse event rate with oxaliplatin in combination with infusional 5-FU is similar to that of capecitabine plus oxaliplatin but is associated with more neutropenia and venous thrombotic events; capecitabine plus oxaliplatin-based regimens tend to be associated with more grade 3 diarrhea and hand-foot skin reaction. Combination therapy with capecitabine and irinotecan (CapeIRI) versus 5-FU/LV and irinotecan (FOLFIRI) had more variable results; some former schedules resulted in excessive treatment-related toxicity. More recent data show that lower capecitabine and irinotecan doses, different schedules, and combination with targeted agents (e.g, bevacizumab) have resulted in more favorable outcomes.     

Optimizing the use of irinotecan in colorectal cancer

The introduction of new agents with novel mechanisms of action has led to considerable changes in the management of colorectal cancer in recent years. One of these novel agents, irinotecan, has been shown to offer survival benefits in both the first- and second-line treatment of advanced/metastatic colorectal cancer. Irinotecan monotherapy improves survival compared with both best supportive care and infused 5-fluorouracil (5-FU) in patients with 5-FU-pretreated disease, without impacting negatively on patients' quality of life. As a result, irinotecan monotherapy is now considered to be the standard treatment in this setting. Irinotecan in combination with 5-FU/leucovorin (LV) was subsequently evaluated as first-line therapy for metastatic colorectal cancer in two randomized, phase III studies. Both trials confirmed that irinotecan plus infused or bolus 5-FU/leucovorin LV provide a modest survival benefit without compromising patients' quality of life. Combined irinotecan/5-FU/LV represents a new standard in the first-line treatment of metastatic colorectal cancer. In an attempt to further improve efficacy and tolerability, recent studies have investigated irinotecan in combination with capecitabine as first-line treatment for colorectal cancer. The replacement of infused 5-FU with oral capecitabine provides a more convenient treatment option. A phase I study was conducted to establish the maximum tolerated dose, and demonstrated encouraging antitumor activity and a manageable safety profile with the combination. This article provides a brief overview of the pivotal clinical trial data for irinotecan and discusses how irinotecan-based therapy may be improved in the future. It also discusses potential optimization of irinotecan use through identification of patient subpopulations most likely to benefit from combination or sequential strategies, and the potential of new, oral agents such as capecitabine to replace i.v. 5-FU as a combination partner for irinotecan.     

First-line oral capecitabine therapy in metastatic colorectal cancer: a favorable safety profile compared with intravenous 5-fluorouracil/leucovorin.

PURPOSE: To evaluate the safety profile of capecitabine using data from a large, well-characterized population of patients with metastatic colorectal cancer treated in two phase II studies. In these trials, capecitabine achieved significantly superior response rates, equivalent time to disease progression and equivalent survival compared with 5-fluorouracil (5-FU)/leucovorin. PATIENTS AND METHODS: Patients (n = 1207) were randomized to either oral capecitabine (1250 mg/m2 twice daily, on days 1-14 every 21 days) or intravenous (i.v.) bolus 5-FU/leucovorin (Mayo Clinic regimen). RESULTS: Capecitabine demonstrated a safety profile superior to that of 5-FU/leucovorin, with a significantly lower incidence of diarrhea, stomatitis, nausea, alopecia and grade 3 or 4 neutropenia leading to significantly fewer neutropenic fever/sepsis cases and fewer hospitalizations. All patients in the capecitabine group received a starting dose of 1250 mg/m2 twice daily and the majority (66%) did not require dose modification for adverse events. In the 5-FU/leucovorin group, 58% of patients did not require dose reduction for toxicities. The capecitabine dose-modification scheme reduced the recurrence of key toxicities without compromising efficacy. In both treatment arms, patients with moderate renal impairment at baseline (estimated creatinine clearance 30-50 ml/min) experienced a higher incidence of grade 3 or 4 toxicities. This increase was more pronounced with 5-FU/leucovorin. CONCLUSIONS: Capecitabine is at least as effective, better tolerated and more convenient than i.v. 5-FU/leucovorin as treatment for patients with metastatic colorectal cancer. Analysis of data from two large phase III trials demonstrates that efficacy is not compromised in patients requiring a dose reduction for adverse events. The phase III data and an additional pharmacokinetic study support a lower starting dose in patients with moderate renal impairment at baseline (calculated creatinine clearance 30-50 ml/min) and a contra-indication in patients with severely impaired creatinine clearance at baseline (<30 ml/min). For patients with normal or mildly impaired renal function at baseline, the standard starting dose is well tolerated. The incidence and severity of adverse events in patients with moderate renal impairment at baseline who were treated with 5-FU/leucovorin was more pronounced, indicating that capecitabine provides a better-tolerated alternative.     

Oral capecitabine compared with intravenous fluorouracil plus leucovorin in patients with metastatic colorectal cancer: results of a large phase III study.

PURPOSE: To compare the efficacy and safety of orally administered capecitabine (Xeloda; Roche Laboratories, Inc, Nutley, NJ), a novel fluoropyrimidine carbamate designed to mimic continuous fluorouracil (5-FU) infusion but with preferential activation at the tumor site, with that of intravenous (IV) 5-FU plus leucovorin (5-FU/LV) as first-line treatment for metastatic colorectal cancer. PATIENTS AND METHODS: We prospectively randomized 602 patients to treatment with capecitabine 1,250 mg/m(2) administered twice daily days 1 to 14 every 3 weeks, or to the 4-weekly Mayo Clinic regimen (5-FU/LV) until disease progression or unacceptable toxicity. RESULTS: The primary objective, to demonstrate at least equivalent response rates in the two treatment groups, was met. The overall response rate was 18.9% for capecitabine and 15.0% for 5-FU/LV. In the capecitabine and 5-FU/LV groups, respectively, median time to disease progression was 5.2 and 4.7 months (log-rank P =.65); median time to treatment failure was 4.2 and 4.0 months (log-rank P =.89); and median overall survival was 13.2 and 12.1 months (log-rank P =.33). The toxicity profiles of both treatments were typical of fluoropyrimidines. However, capecitabine led to significantly lower incidences (P <.00001) of stomatitis and alopecia, but a higher incidence of cutaneous hand-foot syndrome (P <.00001). Capecitabine also resulted in lower incidences (P <.00001) of grade 3/4 stomatitis and neutropenia, leading to a lower incidence of grade 3/4 neutropenic fever and sepsis. Only grade 3 hand-foot syndrome (P <.00001) and uncomplicated grade 3/4 hyperbilirubinemia (P <.0001) were reported more frequently with capecitabine. CONCLUSION: Oral capecitabine achieved an at least equivalent efficacy compared with IV 5-FU/LV. Capecitabine demonstrated clinically meaningful safety advantages and the convenience of an oral agent.     

Integrating oxaliplatin into the management of colorectal cancer

Oxaliplatin, a third-generation platinum analogue, is a novel compound with proven anti-tumor activity in colorectal cancer that has demonstrated synergy with 5-fluorouracil (5-FU) in human tumor xenograft models. A series of phase II trials demonstrated that, as second-line therapy, oxaliplatin in combination with 5-FU/leucovorin (LV) is active and can overcome clinical resistance to 5-FU. Subsequently, two large, randomized, phase III trials demonstrated that the addition of oxaliplatin to 5-FU/LV significantly improved response rates and time to disease progression in the first-line setting, but had no statistically significant impact on survival. Oxaliplatin in combination with 5-FU/LV represents an important treatment option for patients in whom 5-FU-based therapy has failed and as first-line therapy. Oxaliplatin has also been investigated in combination with the oral fluoropyrimidine, capecitabine. As an oral agent that exploits the high intratumoral activity of thymidine phosphorylase to generate 5-FU preferentially within tumor tissue, capecitabine may improve the efficacy and tolerability of fluoropyrimidine/oxaliplatin combination therapy. A phase I dose-escalation study has been performed in patients with advanced/metastatic solid tumors to establish the most appropriate regimen. The study indicated that the combination is feasible and has substantial antitumor activity in patients with colorectal cancer. This article provides an overview of the clinical trial data for oxaliplatin and discusses how oxaliplatin may best be used in the future.     

Phase II trial of capecitabine/irinotecan and capecitabine/oxaliplatin in advanced gastrointestinal cancers

Combination protocols of 5-fluorouracil/leucovorin (5-FU/LV) plus irinotecan or oxaliplatin have demonstrated high activity in metastatic colorectal cancer. Capecitabine, an oral 5-FU prodrug, may replace infusional 5-FU/LV in combination protocols with irinotecan or oxaliplatin. We therefore initiated a phase II study with capecitabine plus either irinotecan or oxaliplatin to determine the efficacy and toxicity of specific combination protocols in patients with advanced gastrointestinal (GI) tumors. Capecitabine 1000 mg/m(2) taken orally twice a day on days 1-14, plus oxaliplatin 70 mg/m(2) on days 1 and 8, or irinotecan 100 mg/m(2) on days 1 and 8; repeated every 3 weeks in an outpatient setting. Patient and tumor characteristics were as follows: median age, 68 years (range, 34-77 years); sex: 10 women, 33 men; tumor types: 35 colorectal cancer; 8 other GI tumors including 5 gastric, 2 pancreatic, and 1 duodenal cancer. All 43 patients treated were evaluable for toxicity (capecitabine/oxaliplatin, 24 patients; capecitabine/irinotecan, 19 patients), and 39 were evaluable for efficacy (capecitabine/oxaliplatin, 22; capecitabine/irinotecan, 17). Grade 3/4 toxicities (National Cancer Institute Common Toxicity Criteria Version 2.0) were limited to diarrhea, 9 patients (capecitabine/irinotecan, n = 5; capecitabine/oxaliplatin, n = 4); hand-foot syndrome, 1 patient (capecitabine/irinotecan); nausea, 2 patients (capecitabine/oxaliplatin); vomiting, 1 patient (capecitabine/oxaliplatin); and peripheral neuropathy, 1 patient (capecitabine/oxaliplatin). No grade 3/4 myelosuppression was noted for either protocol. Capecitabine/irinotecan and capecitabine/oxaliplatin demonstrated significant clinical activity in colorectal cancer and other GI cancers as first-line and salvage therapy. Capecitabine/oxaliplatin and capecitabine/irinotecan show an excellent safety profile and clinical activity in colorectal cancer and other advanced GI tumors. The main toxicity in both arms was manageable diarrhea. This trial served as basis for a randomized multicenter phase II study comparing capecitabine/oxaliplatin and capecitabine/irinotecan as first-line therapy in patients with advanced colorectal cancer.     

Pharmacoeconomic analysis of adjuvant oral capecitabine vs intravenous 5-FU/LV in Dukes' C colon cancer: the X-ACT trial

Oral capecitabine (Xeloda) is an effective drug with favourable safety in adjuvant and metastatic colorectal cancer. Oxaliplatin-based therapy is becoming standard for Dukes' C colon cancer in patients suitable for combination therapy, but is not yet approved by the UK National Institute for Health and Clinical Excellence (NICE) in the adjuvant setting. Adjuvant capecitabine is at least as effective as 5-fluorouracil/leucovorin (5-FU/LV), with significant superiority in relapse-free survival and a trend towards improved disease-free and overall survival. We assessed the cost-effectiveness of adjuvant capecitabine from payer (UK National Health Service (NHS)) and societal perspectives. We used clinical trial data and published sources to estimate incremental direct and societal costs and gains in quality-adjusted life months (QALMs). Acquisition costs were higher for capecitabine than 5-FU/LV, but higher 5-FU/LV administration costs resulted in 57% lower chemotherapy costs for capecitabine. Capecitabine vs 5-FU/LV-associated adverse events required fewer medications and hospitalisations (cost savings pound3653). Societal costs, including patient travel/time costs, were reduced by >75% with capecitabine vs 5-FU/LV (cost savings pound1318), with lifetime gain in QALMs of 9 months. Medical resource utilisation is significantly decreased with capecitabine vs 5-FU/LV, with cost savings to the NHS and society. Capecitabine is also projected to increase life expectancy vs 5-FU/LV. Cost savings and better outcomes make capecitabine a preferred adjuvant therapy for Dukes' C colon cancer. This pharmacoeconomic analysis strongly supports replacing 5-FU/LV with capecitabine in the adjuvant treatment of colon cancer in the UK.     

Rational development of capecitabine

Capecitabine is a fluoropyrimidine carbamate that was rationally designed as an oral drug capable of mimicking continuous infusion 5-fluorouracil (5-FU) and delivering 5-FU preferentially to tumour tissue. Following extensive absorption, capecitabine is rapidly converted to 5-FU via a three-step enzymatic pathway. The final step depends on thymidine phosphorylase, an enzyme present at higher concentrations in malignant compared with normal tissue. This results in the delivery of 5-FU preferentially to the tumour site. Capecitabine has demonstrated high activity in preclinical xenograft models for a wide range of human solid tumours, including those resistant to 5-FU. Phase I studies have determined the maximum tolerated dose (MTD) of capecitabine and identified a number of dosage regimens, which were subsequently evaluated in a randomised, phase II study as first-line treatment for metastatic colorectal cancer. This established an intermittent regimen of capecitabine 1250 mg/m2 twice daily for 14 days followed by a 7-day rest period as the most appropriate regimen for further clinical development.     

Xeloda in Adjuvant Colon Cancer Therapy (X-ACT) trial: overview of efficacy, safety, and cost-effectiveness

The X-ACT (Xeloda in Adjuvant Colon Cancer Therapy) trial compared the efficacy and safety of the oral fluoropyrimidine capecitabine with bolus 5-fluorouracil (5-FU)/leucovorin (LV; Mayo Clinic regimen) as adjuvant therapy for stage III colon cancer. A total of 1987 patients were enrolled at 164 centers worldwide. Disease-free survival (primary study endpoint) in the capecitabine arm was at least equivalent to that in the 5-FU/LV arm; the upper limit of the hazard ratio was significantly (P < 0.001) below the predefined margins for noninferiority. Capecitabine was also associated with significantly fewer fluoropyrimidine-related grade 3/4 adverse events (AEs; P < 0.001) and fewer AE-related hospital admissions/days than 5-FU/LV. Pharmacoeconomic analyses performed in several countries show that the savings in direct costs (drug administration and AE-related costs) associated with capecitabine versus 5-FU/LV offset the acquisition costs of the drug. Furthermore, capecitabine reduces patient travel time and costs, making it a "dominant" strategy (ie, less costly and more effective) in the adjuvant setting. In conclusion, efficacy, safety, convenience, and cost findings from the X-ACT trial show that capecitabine offers at least equivalent clinical benefit compared with bolus 5-FU/LV and can replace intravenous 5-FU/LV in the adjuvant treatment of stage III colon cancer. The X-ACT trial has not only helped to better define the role of capecitabine but has also broadened the options available to patients with early-stage disease to include a uniquely effective oral outpatient treatment.