Optimisation of irinotecan dose in the treatment of patients with metastatic colorectal cancer after 5-FU failure: results from a multinational, randomised phase II study.

Although irinotecan 350 mg m(-2) is a standard option for relapsed/refractory advanced colorectal cancer, there is some evidence that suggests that a higher dose may be more effective, with acceptable tolerability, following 5-fluorouracil (5-FU). This study assessed the optimal dosing strategy for irinotecan, along with treatment efficacy and safety. A total of 164 patients with metastatic colorectal cancer progressing after failure on 5-FU or raltitrexed received either 350 mg m(-2) irinotecan (Group A; n=36) or 250, 350 or 500 mg m(-2), according to individual patient tolerance (Group B; n=62) or based on risk factor optimisation (Group C; n=66). There were no complete responses. There was a trend towards a higher overall response rate in Group B (13%) than in Groups A (8%) and C (9%). Tumour control growth rate was high in all three groups: 58% in group A, 60% in Group B and 50% in Group C. A total of 34% of patients in Group B and 9% in Group C were able to receive a dose of 500 mg m(-2). Median duration of response and time to progression were significantly longer in Groups A and B compared with Group C. No significant between-group differences for any adverse events were seen, although there was a small trend towards better tolerability in Group B. Individual dose escalation based on patient tolerance may allow more patients to receive a higher irinotecan dose without causing additional toxicity and can be an appropriate patient management strategy.

A randomised phase II multicentre trial of irinotecan (CPT-11) using four different schedules in patients with metastatic colorectal cancer.

The purpose of this phase II trial was to compare the efficacy, safety and pharmacokinetics of four irinotecan schedules for the treatment of metastatic colorectal cancer. In total, 174 5-fluorouracil pretreated patients were randomised to: arm A (n=41), 350 mg m(-2) irinotecan as a 90-min i.v. infusion q3 weeks; arm B (n=38), 125 mg m(-2) irinotecan as a 90-min i.v. infusion weekly x 4 weeks q6 weeks; arm C (n=46), 250 mg m(-2) irinotecan as a 90-min i.v. infusion q2 weeks; or arm D (n=49), 10 mg m(-2) day(-1) irinotecan as a 14-day continuous infusion q3 weeks. No significant differences in efficacy across the four arms were observed, although a shorter time to treatment failure was noted for arm D (1.7 months; P=0.02). Overall response rates were in the range 5-11%. Secondary end points included median survival (6.4-9.4 months), and time to progression (2.7-3.8 months) and treatment failure (1.7-3.2 months). Similarly, there were no significant differences in the incidence of grade 3-4 toxicities, although the toxicity profile between arms A, B, and C and D did differ. Generally, significantly less haematologic toxicity, alopecia and cholinergic syndrome were observed in arm D; however, there was a trend for increased gastrointestinal toxicity. Irinotecan is an effective and safe second-line treatment for colorectal cancer. The schedules examined yielded equivalent results, indicating that there is no advantage of the prolonged vs short infusion schedules.

Continuous infusion of hepatic arterial irinotecan in pretreated patients with colorectal cancer metastatic to the liver.

BACKGROUND: Irinotecan is an active drug in colorectal cancer. In patients with liver metastases, hepatic arterial infusion of irinotecan could theoretically result in higher exposure to the drug. In order to determine the efficacy of hepatic arterial irinotecan we conducted a phase II study in pretreated patients with liver metastases of colorectal cancer. PATIENTS AND METHODS: Patients with measurable liver metastases of colorectal cancer with World Health Organization performance status (WHO PS) <2 were treated with a 5-day continuous infusion of hepatic arterial irinotecan every 3 weeks at a dose of 20 mg/m(2)/day. RESULTS: Of the 25 patients included, 22 were evaluable for response. Three of 22 patients (13.6%) had a partial response, nine (40.9%) had stable disease and 10 (45.4%) had progressive disease. No complete responses were observed. Median time to progression was 2.8 (range 1.2-23.8) months. Major toxicities were vomiting and diarrhea. There was no major hematological toxicity. CONCLUSIONS: Five-day continuous hepatic arterial infusion of irinotecan 20 mg/m(2)/day has low activity in patients with liver metastases of colorectal cancer previously treated by chemotherapy.

Irinotecan plus fluorouracil/leucovorin for metastatic colorectal cancer: a new survival standard.

BACKGROUND: Irinotecan is a topoisomerase I inhibitor that prolongs survival in patients with colorectal cancer refractory to fluorouracil (5-FU) and leucovorin (LV). This demonstrated activity of irinotecan as effective second-line therapy for colorectal cancer led to evaluation of combination irinotecan/5-FU/LV as first-line therapy for patients with metastatic disease. The results of two prospective phase III randomized, controlled, multicenter, multinational clinical trials in patients with previously untreated metastatic colorectal cancer served as the basis for U.S. and European approval of irinotecan/5-FU/LV for this indication. An overview of the findings of these two pivotal studies provides insights regarding the application of this new combination in clinical practice. METHODS: Patients were randomly assigned to receive 5-FU/LV, either alone, or with concurrent irinotecan. The study conducted primarily in North America (study 1), employed bolus 5-FU/LV schedules, while the study performed primarily in Europe (study 2), employed infusional 5-FU/LV regimens. Major endpoints included tumor response rate, time to tumor progression (TTP), overall survival, quality of life, and safety. RESULTS: In study 1, the respective confirmed response rates for irinotecan/5-FU/LV versus 5-FU/LV were 39% and 21% (p <.001); median TTPs were 7.0 months and 4.3 months, respectively (p =.004). In study 2, response rates for irinotecan/5-FU/LV versus 5-FU/LV alone were 35% and 22% (p =.005); median TTPs were 6.7 months and 4.4 months, respectively (p <.001). Survival time increased significantly with irinotecan/5-FU/LV versus 5-FU/LV alone in both studies (study 1: median 14.8 months versus 12.6 months, p =.042; study 2: median 17.4 months versus 14.1 months, p =.032). The combined analysis of the data from the two studies showed median survivals of 15.9 months versus 13.3 months, favoring the irinotecan-containing combinations (stratified-by-study p =.003). Patients in study 1 had a 36% lower risk of tumor progression and a 20% lower risk of death with the irinotecan combination than with 5-FU/LV alone; comparable risk reduction values in study 2 were 42% and 23%. While grade 3 diarrhea and vomiting were more common with irinotecan/5-FU/LV, grade 4 neutropenia, neutropenic fever, and mucositis were less common with irinotecan/5-FU/LV than with the Mayo Clinic 5-FU/LV regimen. CONCLUSION: The combination of irinotecan/5-FU/LV is superior to 5-FU/LV alone as first-line therapy for patients with metastatic colorectal cancer, offering consistently improved tumor control and prolonged survival. Irinotecan-based combination therapy sets a new survival standard for the treatment of this life-threatening disease.

Phase I study of irinotecan and raltitrexed in patients with advanced gastrointestinal tract adenocarcinoma.

To determine the dose-limiting toxicities (DLT) and maximum tolerated dose (MTD) of irinotecan and raltitrexed given as sequential short infusions every 3 weeks, 33 patients with pretreated gastrointestinal adenocarcinoma (31 colorectal, 2 oesophagogastric) entered this open label dose-escalation study. For the first five dose levels patients received irinotecan 175-350 mg m(-2) followed by raltitrexed 2.6 mg m(-2). Level VI was irinotecan 350 mg m(-2) plus raltitrexed 3.0 mg m(-2), level VII was irinotecan 400 mg m(-2) plus raltitrexed 2.6 mg m(-2); 261 courses were administered. Only one patient at dose levels I-V experienced DLT. At level VI, 5/12 patients experienced DLT: one had grade 3 diarrhoea and lethargy, one had grade 4 diarrhoea and one had lethargy alone. Two others had lethargy caused by disease progression. There was no first-cycle neutropenia. At level VII, 3/6 patients experienced dose-limiting lethargy, one also had grade 3 diarrhoea. Dose intensity fell from over 90% for both drugs at level VI to 83% for irinotecan and 66% for raltitrexed at level VII. Lethargy was therefore the DLT, and level VII the MTD. Pharmacokinetic data showed no measurable drug interaction; 6/30 patients (20%) had objective responses. This combination is active with manageable toxicity. Recommended doses for further evaluation are irinotecan 350 mg m(-2) and raltitrexed 3.0 mg m(-2).

Irinotecan combined with fluorouracil compared with fluorouracil alone as first-line treatment for metastatic colorectal cancer: a multicentre randomised trial.

BACKGROUND: Irinotecan is active against colorectal cancer in patients whose disease is refractory to fluorouracil. We investigated the efficacy of these two agents combined for first-line treatment of metastatic colorectal cancer. METHODS: 387 patients previously untreated with chemotherapy (other than adjuvant) for advanced colorectal cancer were randomly assigned open-label irinotecan plus fluorouracil and calcium folinate (irinotecan group, n=199) or fluorouracil and calcium folinate alone (no-irinotecan group, n=188). Infusion schedules were once weekly or every 2 weeks, and were chosen by each centre. We assessed response rates and time to progression, and also response duration, survival, and quality of life. Analyses were done on the intention-to-treat population and on evaluable patients. FINDINGS: The response rate was significantly higher in patients in the irinotecan group than in those in the no-irinotecan group (49 vs 31%, p<0.001 for evaluable patients, 35 vs 22%, p<0.005 by intention to treat). Time to progression was significantly longer in the irinotecan group than in the no-irinotecan group (median 6.7 vs 4.4 months, p<0.001), and overall survival was higher (median 17.4 vs 14.1 months, p=0.031). Some grade 3 and 4 toxic effects were significantly more frequent in the irinotecan group than in the no-irinotecan group, but effects were predictible, reversible, non-cumulative, and manageable. INTERPRETATION: Irinotecan combined with fluorouracil and calcium folinate was well-tolerated and increased response rate, time to progression, and survival, with a later deterioration in quality of life. This combination should be considered as a reference first-line treatment for metastatic colorectal cancer.

Phase I and pharmacokinetic study of irinotecan administered as a low-dose, continuous intravenous infusion over 14 days in patients with malignant solid tumors.

PURPOSE: To evaluate the feasibility of administering irinotecan as a continuous intravenous infusion for 14 to 21 days. PATIENTS AND METHODS: Patients with solid tumors refractory to standard therapy received continuous infusions of irinotecan by means of an ambulatory infusion pump. The starting dosage was 12.5 mg/m(2)/d for 14 days every 3 weeks. After identification of the maximum-tolerated dose for the 14-day infusion schedule, the protocol was amended to prolong the infusion duration to 17 and 21 days. Pharmacokinetics of irinotecan and SN-38 and its glucuronide were determined using high-performance liquid chromatography and noncompartmental modeling. RESULTS: Thirty-three patients received 85+ courses. At the first dose level (12.5 mg/m(2)/d), cumulative grade 3 or 4 diarrhea and grade 3 or 4 neutropenia occurred in three of five patients. At a dosage of 10 mg/m(2)/d, 14-day administration resulted in grade 4 diarrhea in two of six patients and one episode of grade 4 vomiting occurred, whereas with 17-day administration, one episode of grade 3 nausea and two episodes of grade 3 or 4 diarrhea were observed in six patients. Increasing the number of days of infusion to 21 days was not feasible because of cumulative diarrhea. Hematologic toxicity was rare. The mean metabolic SN-38 area under the curve/irinotecan area under the curve ratio was 16% +/- 6% compared with 3% to 5% after short infusion schedules involving therapeutic dosages. Partial responses were observed in two patients with extraovarian and colorectal cancer. CONCLUSION: The recommended dosage is 10 mg/m(2)/d for 14 days, repeated every 3 weeks. Enhanced metabolism of irinotecan to SN-38 may explain in part the low recommended dose for this schedule.

Long-term survival of patients with unresectable colorectal cancer liver metastases following infusional chemotherapy with 5-fluorouracil, leucovorin, oxaliplatin and surgery.

CONTEXT: Long-term survival of patients with metastatic colorectal cancer has been achieved only in patients who underwent complete resection of metastases. Such surgery could be performed in a greater proportion of patients if effective chemotherapy could downstage previously unresectable metastases. This approach has been limited by the low tumor response rate achieved with conventional chemotherapy. OBJECTIVE: We studied the outcome of patients with initially unresectable liver metastases from colorectal cancer treated with a three-drug chemotherapy regimen followed by liver metastases surgery whenever possible. PATIENTS AND METHODS: From March 1988 to June 1994, 151 patients with colorectal liver metastases were considered initially unresectable because of large tumor size (> 5 cm), multinodular (> 4) or ill-located metastases. All patients received fully ambulatory chemotherapy with 5-fluorouracil, leucovorin and oxaliplatin (chronotherapy in 83% of them). They were periodically reassessed for surgery by a joint medico-surgical team. RESULTS: In 151 patients, the size of liver metastases decreased by > 50% in 89 patients (59%) and median overall survival was 24 months (95% confidence interval (95% CI): 19-28 months), with 28% surviving at five years (20%-35%). Surgery with curative intent was attempted in 77 patients (51%), complete resection of liver metastases was achieved in 58 patients (38%). The median survival of the 77 operated patients was 48 months (25-71), with a five-year survival rate of 50% (38-61). CONCLUSION: This new strategy of combining effective chemotherapy with surgery apparently altered the natural history of unresectable colorectal cancer metastases.

Dose-finding study of docetaxel and doxorubicin in first-line treatment of patients with metastatic breast cancer.

PURPOSE: To determine the maximum tolerated dose (MTD), the dose-limiting toxicity (DLT) and the recommended dose of docetaxel in combination with doxorubicin, and to evaluate the activity in patients with advanced breast cancer. PATIENTS AND METHODS: Forty-two women with untreated metastatic breast cancer (79% with visceral metastases; 52% with prior adjuvant anthracycline therapy) were treated with doxorubicin (40-60 mg/m2) i.v. bolus followed one hour later by docetaxel (50-85 mg/m2) one-hour i.v. infusion every three weeks, without G-CSF support. RESULTS: The MTD occurred at the dose level combining 85 mg/m2 of docetaxel and 50 mg/m2 of doxorubicin, with the DLT being neutropenic sepsis. Neutropenia and/or its complications were manageable and no grade 3-4 or severe non-hematological toxicities were observed. Fluid retention was frequent but never severe. With a median cumulative dose of doxorubicin of 392 mg/m2 (240-559 mg/m2) and a median follow-up time of 29 months (9(+)-41), no congestive heart failure was observed. High activity was observed at all dose levels, particularly the last four, with a response rate of 81% (95% confidence interval (95% CI): 62.5-92.5). Median time to progression was 46 weeks (6(+)-62). Two-year survival was 66%, and median survival has not yet been reached. CONCLUSIONS: Docetaxel-doxorubicin is feasible, safe and highly active. The incidence of febrile neutropenia without G-CSF requires careful monitoring but is acceptable in this setting. There does not appear to be an increase in the cardiac toxicity of doxorubicin. The recommended doses is either docetaxel 75 mg/m2 and doxorubicin 50 mg/m2 or docetaxel 60 mg/m2 and doxorubicin 60 mg/m2, administered every three weeks.

Treatment with a nonanthracycline regimen in advanced breast cancer: vinorelbine, cyclophosphamide, and 5-fluorouracil with folinic acid.

The efficacy of combination therapy with vinorelbine, cyclophosphamide, and 5-fluorouracil was assessed in women who had received no prior therapy for locally advanced or metastatic breast cancer. Sixty patients with metastatic breast cancer who had finished any adjuvant therapy at least 6 months previously and who had not received treatment for advanced disease were entered onto the study. The schedule consisted of vinorelbine (Navelbine, Pierre Fabre Medicament) 25 mg/m2 on days 1 and 8, cyclophosphamide 500 mg/m2 on day 1, and 5-fluorouracil 500 mg/m2 followed by folinic acid 200 mg/m2 on days 1 and 8. Treatment was repeated every 21 days up to a maximum of 8 cycles. Objective responses were observed in 27 of 60 patients (45%; CI95 32.4-57.6) including 4 complete responses (6.7%; CI95 0-13) and 23 partial responses (38.3%; CI95 22.5-54.1). The responses were achieved in both visceral and nonvisceral sites and at the same rate for patients with multiple sites of disease. Neutropenia was dose limiting, with 40% of patients affected at grade 3 or 4, while other hematologic and nonhematologic toxicity was very mild. This schedule achieves good levels of response without the use of an anthracycline, so it is suitable either for patients who have been extensively exposed to anthracyclines during adjuvant therapy or for those who have other contraindications to their use.

A phase II study of irinotecan alternated with five days bolus of 5-fluorouracil and leucovorin in first-line chemotherapy of metastatic colorectal cancer.

PURPOSE: This multicenter phase II study was designed to assess the efficacy of the alternating schedule of irinotecan (CPT-11) with bolus 5-fluorouracil (5-FU) and leucovorin (LV) in first-line chemotherapy for metastatic colorectal cancer (CRC). PATIENTS AND METHODS: Patients with histologically proven metastatic colorectal cancer, and at least one bidimensionally measurable lesion, aged 18-70, with performance status < or = 2, normal baseline biological values and no prior chemotherapy (or only adjuvant chemotherapy completed > or = 6 months before study entry) were selected. Treatment was irinotecan 350 mg/m2, i.v., day 1, alternating with leucovorin 20 mg/m2 i.v. and 5-FU 425 mg/m2, i.v. daily for five consecutive days, day 22-26 (Mayo Clinic regimen). One alternating cycle was to be performed every six weeks. Patients were evaluated for efficacy every alternating cycle. Treatment was administered until five alternating cycles, disease progression, unacceptable toxicity or patient refusal. RESULTS: Thirty-three patients (28 chemotherapy-naïve and five with prior adjuvant treatment completed > 1 year prior to accrual) were enrolled. The objective response rate (RR) was 30% (95% CI: 16-49; 10 patients/33; nine partial response and one complete response). All responses were reviewed by an independent external review committee. An additional 49% of patients had stable disease. The median survival was 16 months, the one year survival amounted to 58% and the median progression free survival was 7.2 months. Relative dose intensity was nearly 90% for both drugs. Grade 3-4 diarrhea and neutropenia were the most frequent severe toxic events, seen in 24% and 64% of patients, respectively. CONCLUSIONS: The alternating schedule of CPT-11 350 mg/m2 with five days bolus of 5-FU and low dose LV is an active and feasible regimen as front-line therapy for metastatic CRC. It is well tolerated, without evidence of overlapping toxicity. The response rate appears promising with regard to that expected with either single agent. This regimen warrants further assessment in randomized trials.