Phase I study of weekly oxaliplatin plus irinotecan in previously treated patients with metastatic colorectal cancer

Oxaliplatin-induced peripheral neurotoxicity in colorectal cancer patients: mechanisms, pharmacokinetics and strategies

Oxaliplatin-based chemotherapy is a standard treatment approach for colorectal cancer (CRC). However, oxaliplatin-induced peripheral neurotoxicity (OIPN) is a severe dose-limiting clinical problem that might lead to treatment interruption. This neuropathy may be reversible after treatment discontinuation. Its complicated mechanisms are related to DNA damage, dysfunction of voltage-gated ion channels, neuroinflammation, transporters, oxidative stress, and mitochondrial dysfunction, etc. Several strategies have been proposed to diminish OIPN without compromising the efficacy of adjuvant therapy, namely, combination with chemoprotectants (such as glutathione, Ca/Mg, ibudilast, duloxetine, etc.), chronomodulated infusion, dose reduction, reintroduction of oxaliplatin and topical administration [hepatic arterial infusion chemotherapy (HAIC), pressurized intraperitoneal aerosol chemotherapy (PIPAC), and hyperthermic intraperitoneal chemotherapy (HIPEC)]. This article provides recent updates related to the potential mechanisms, therapeutic strategies in treatment of OIPN, and pharmacokinetics of several methods of oxaliplatin administration in clinical trials.

Oncolytic vaccinia virus synergizes with irinotecan in colorectal cancer

Metastatic colorectal cancer (CRC) is complex clinical challenge for which there are limited treatment options. Chemotherapy with or without surgery provides moderate improvements in overall survival and quality of life; nevertheless the 5-year survival remains below 30%. Oncolytic vaccinia virus (VV) shows strong anti-tumour activity in models of CRC, however transient delays in disease progression are insufficient to lead to long-term survival. Here we examined the efficacy of VV with oxaliplatin or SN-38 (active metabolite of irinotecan) in CRC cell lines in vitro and VV with irinotecan in an orthotopic model of metastatic CRC. Synergistic improvements in in vitro cell killing were observed in multiple cell lines. Combination therapy was well tolerated in tumour-bearing mice and the median survival was significantly increased relative to monotherapy despite a drug-dependent decrease in the mean tumour titer. Increased apoptosis following in vitro and in vivo combination therapy was observed. In vitro cell cycle analysis showed increases in S-phase cells following infection occurred in both infected and uninfected cell populations. This corresponded to a 4-fold greater increase in apoptosis in the uninfected compared to infected cells following combination therapy. Combination treatment strategies are among the best options for patients with advanced cancers. VV is currently under clinical investigation in patients with CRC and the data presented here suggest that its combination with irinotecan may provide benefit to a subset of CRC patients. Further, investigation of this combination is necessary to determine the tumour characteristics responsible for mediating synergy.

Analysis for prognostic factors of 60-day mortality: evaluation of an irinotecan-based phase III trial performed in the first-line treatment of metastatic colorectal cancer

BACKGROUND

Mortality rates in published irinotecan-based trials range between 1.7% and 5.0%. This analysis aimed to evaluate clinical and histopathologic factors associated with 60-day mortality in first-line therapy for metastatic colorectal cancer (mCRC).

PATIENTS AND METHODS

Sixty-day all-cause and disease-specific mortality rates from 479 patients who participated in a randomized phase III study comparing FUFIRI (5-fluorouracil [5-FU], leucovorin, irinotecan) (n = 238) vs. mIROX (modified irinotecan plus oxaliplatin (n = 241) were evaluated for association with prognostic factors such as platelet counts, alkaline phosphatase (AP) levels, white blood cell (WBC) counts, hemoglobin values, lactate dehydrogenase (LDH) levels, carcinoembryonic antigen (CEA) levels, and several other baseline parameters using univariate and multivariate logistic regression analyses applied to patients combined from both treatment groups.

RESULTS

The all-cause 60-day mortality rate was 5.0% (24/479). Thirteen patients (5.5%) in the FUFIRI arm died within the first 60 days of treatment compared with 11 (4.6%) patients in the mIROX arm (P = .68). Among the 24 patients in both treatment arms, mortality was qualified as disease related in 15 (63%) patients and treatment related in 7 (29%) patients (P = .695). In multivariate analyses, high LDH levels (P = .010) and an elevated WBC count (P = .006) remained as significant independent prognostic factors. Low Karnofsky performance status (KPS) showed a strong trend but failed to reach statistical significance (P = .057) as did AP levels and the number of metastatic sites.

CONCLUSION

In this study 63% of the early deaths were disease related, whereas only 29% were possibly related to study medication. Independent prognostic factors for early mortality were LDH levels and WBC counts. KPS showed a strong trend in the multivariate analysis. Future investigation may consider LDH levels and WBC counts for exclusion criteria.

Phase 1 study of oxaliplatin and irinotecan in pediatric patients with refractory solid tumors: a children's oncology group study

BACKGROUND

For this report, the authors estimated the maximum tolerated dose (MTD) and investigated the toxicities of oxaliplatin combined with irinotecan in children with refractory solid tumors.

METHODS

Oxaliplatin was administered on Days 1 and 8 in combination with irinotecan on Days 1 through 5 and Days 8 through 12 of a 21-day cycle. An oral cephalosporin was administered daily to ameliorate irinotecan-associated diarrhea. Pharmacokinetic studies of oxaliplatin and uridine diphosphate glucuronosyltransferase 1 family, polypeptide A1 (UGT1A1) genotyping were performed.

RESULTS

Thirteen patients were enrolled. Dose-limiting diarrhea (n = 3), serum lipase elevation (n = 3), serum amylase elevation (n = 2), colitis, abdominal pain, and headache (n = 1 each) occurred at the first dose level (oxaliplatin at a dose of 60 mg/m(2); irinotecan at a dose of 20 mg/m(2)). Only 1 of 7 patients who received reduced doses of both agents (40 mg/m(2)/dose oxaliplatin; 15 mg/m(2)/dose irinotecan) experienced a dose-limiting toxicity (DLT): diarrhea. When the oxaliplatin dose was re-escalated (60 mg/m(2)) with irinotecan at a dose of 15 mg/m(2), 2 of 3 patients had a DLT (1 episode of diarrhea, 1 episode of hypokalemia). Myelosuppression was minimal. One patient had a complete response, and another patient had stable disease for 6 cycles of therapy. The median oxaliplatin area under the concentration versus time curve (AUC(0-->infinity)) was 5.9 microg . hour/mL (range, 1.8-7.6 microg . hour/mL). The frequency of the 6/6, 6/7, and 7/7 UGT1A1 promoter genotypes was 5 of 10, 4 of 10, and 1 of 10, respectively.

CONCLUSIONS

The oxaliplatin MTD was 40 mg/m(2) per dose on Days 1 and 8 in combination with irinotecan 15 mg/m(2) per dose on Days 1-5 and Days 8-12. There was some evidence of antitumor activity; however, severe toxicity, both expected (diarrhea) and unexpected (elevation in pancreatic enzymes), was observed.

Phase I clinical and pharmacokinetic study of oxaliplatin, irinotecan and capecitabine

PURPOSE

To determine the maximum tolerated dose (MTD) and dose-limiting toxicity (DLT) of the combination of weekly oxaliplatin x 4, weekly irinotecan x 4 and capecitabine Monday through Friday for 4 weeks of every 6 week cycle in patients with solid tumors; to determine the pharmacokinetic profile of these agents in this combination; to observe patients for clinical anti-tumor response.

METHODS

Twenty-two patients with metastatic solid tumors received oxaliplatin 60 mg/m(2) weekly x 4, irinotecan beginning at a dose of 40 mg/m(2) weekly x 4, and capecitabine Monday through Friday for 4 weeks of every 6 week cycle, initially at 1,000 mg twice daily (bid).

RESULTS

The MTD was oxaliplatin 60 mg/m(2) weekly x 4, irinotecan 50 mg/m(2) weekly x 4 and capecitabine 450 mg bid Monday through Friday for 4 weeks of every 6 week cycle. One of six patients at this dose level developed DLT of nausea, vomiting, and diarrhea. Among patients treated with a constant capecitabine dose of 450 mg bid, there was a higher mean AUC of 5-FU in women than in men (mean +/- SD: 892 +/- 287 nM h vs. 537 +/- 182 nM h; Mann-Whitney two-tailed, P = 0.02). There was one complete response in a patient with gastric cancer.

CONCLUSION

The novel schedule of weekly oxaliplatin, weekly irinotecan, and capecitabine Monday through Friday, all administered for 4 weeks of every 6 week cycle, evaluated in this phase I trial is well-tolerated and demonstrated activity in a patient with gastric cancer.

Oxaliplatin Plus Irinotecan Compared With Irinotecan Alone as Second-Line Treatment After Single-Agent Fluoropyrimidine Therapy for Metastatic Colorectal Carcinoma

Purpose

To determine whether irinotecan plus oxaliplatin (IROX) is superior to irinotecan alone in patients with metastatic colorectal cancer (CRC) previously treated with single-agent fluoropyrimidines.

Patients and Methods

A phase III, randomized, open-label, multicenter study of patients with metastatic or recurrent CRC that had progressed or recurred during or after adjuvant or first-line fluoropyrimidines (fluorouracil/leucovorin or capecitabine, the latter only for metastatic CRC). Patients received IROX (irinotecan 200 mg/m2 plus oxaliplatin 85 mg/m2) or irinotecan alone (350 mg/m2) every 3 weeks.

Results

At the data cutoff (when 447 of 628 randomly assigned patients had died), median overall survival was 13.4 months (95% CI, 12.4 to 14.7 months) and 11.1 month (95% CI, 10.0 to 12.7 months) in the IROX and irinotecan groups, respectively (hazard ratio = 0.78; 95% CI, 0.65 to 0.94; P = .0072). Overall response rate (22% v 7%, respectively; P < .0001), median time to progression (5.3 v 2.8 months, respectively; P < .0001), and improvement in tumor-related symptoms (32% v 19%, respectively; P = .0072) were also improved with IROX as compared with irinotecan. With the exception of granulocytopenia (25% v 13%), diarrhea (28% v 23%), and sensory disturbances (5% v 0%), grade 3 to 4 toxicities were comparable between the IROX and irinotecan groups, respectively.

Conclusion

IROX is an effective treatment for metastatic CRC that has progressed after first-line fluoropyrimidine therapy. IROX improves efficacy compared with irinotecan alone, providing an additional option in the postadjuvant or second-line treatment setting for patients who experience treatment failure with single-agent fluoropyrimidine therapy.

Irinotecan, oxaliplatin plus bolus 5-fluorouracil and low dose folinic acid every 2 weeks: a feasibility study in metastatic colorectal cancer patients

OBJECTIVES

Irinotecan or oxaliplatin combined with 5-fluorouracil (5-FU) +/- folinic acid (FA) has changed the treatment standards for metastatic colorectal cancer (CRC). The oxaliplatin and irinotecan combination has reported consistent activity. The purpose of this phase II study was to assess the efficacy and safety of the simultaneous administration of a triple chemotherapy combination of oxaliplatin, irinotecan, 5-FU bolus, and FA.

MATERIALS AND METHODS

Eligible patients had metastatic CRC with no prior oxaliplatin or irinotecan-based chemotherapy. Treatment consisted of oxaliplatin 85 mg/m2 followed by irinotecan 150 mg/m2, repeated every 15 days, with 5-FU 500 mg/m2 bolus and FA 20 mg/m2 on days 1, 8, and 15. An early amendment suppressed the day 8 5-FU/FA.

RESULTS

Twenty-six eligible treated patients receiving 253 doses were assessed for toxicity. Myelosuppression was the most frequent toxicity; grade 3 to 4 neutropenia and febrile neutropenia occurred in 50% and 15% of patients, respectively. The treatment schedule modification, omitting the 5-FU dosing on day 8, considerably improved treatment compliance, reducing the incidence of febrile neutropenia, diarrhea, and asthenia. Among the 25 patients evaluable for efficacy, 10 had objective responses including 1 complete response (CR) (4%) and 9 partial responses (PR) (36%), giving an overall response rate of 40%. Median time to progression was 6.20 months [95% confidence interval (CI), 5.44-6.96]. Median overall survival was 12.95 months.

CONCLUSIONS

The administration of a triple combination produced promising objective responses with acceptable toxicity but does not seem to produce an evident benefit in time-related parameters.

Phase II trial of combined irinotecan and oxaliplatin given every 3 weeks to patients with metastatic colorectal cancer

BACKGROUND

Both irinotecan and oxaliplatin are active agents in the treatment of patients with metastatic colorectal cancer, and there is a strong preclinical rationale for combining these 2 agents. Therefore, a Phase II trial was designed and conducted to determine the efficacy and tolerability of combined irinotecan and oxaliplatin given every 3 weeks to patients with metastatic colorectal cancer.

METHODS

Patients with previously untreated metastatic colorectal cancer received irinotecan at a dose of 175 mg/m2 and oxaliplatin at a dose of 130 mg/m2, both given intravenously every 3 weeks. Objective responses were evaluated every 2 courses and were confirmed at least 4 weeks after the initial determination.

RESULTS

Fifty-five patients were enrolled and treated in the current trial. Of the 53 patients whose responses were evaluable, 18 (34%) achieved a partial response, 27 (51%) had stable disease, and 8 (15%) developed disease progression as their best response to the treatment. The intent-to-treat median survival for all patients was 16.4 months and the time to progression was 4.8 months. All 55 patients were available for toxicity analysis (according to version 2.0 of the National Cancer Institute Common Toxicity Criteria). The most common Grade 3-4 toxic effect was neutropenia, which was reported to occur in 22 patients (40%).

CONCLUSIONS

The combination of irinotecan and oxaliplatin appears to be safe and active when used to treat patients with metastatic colorectal cancer. Treatment results with this regimen were similar to those reported for other combined frontline chemotherapy regimens for colorectal cancer. When this particular regimen wa used, neutropenia was found to be the predominant toxicity.

A Bayesian evaluation of enrolling additional patients at the maximum tolerated dose in Phase I trials

At the end of the dose escalation stage of Phase I trials, investigators occasionally enroll additional patients at the maximum tolerated dose (MTD) to further explore the tolerability of the regimen. There is no explicit statistical justification for doing so; neither are there any guidelines regarding the use of toxicity information from this additional cohort with respect to the modification of MTD if necessary. This article addresses both of these issues using a Bayesian approach to model the probability of dose limiting toxicity (DLT) at the MTD. This approach takes the sequential nature of the Phase I design into account and provides predictive and posterior distributions through which various probabilities of interest can be calculated. The results suggest that MTD is usually not well defined with a cohort of 3-6 patients in the traditional dose escalation schema. Therefore, enrolling additional patients at the MTD is recommended. Also demonstrated are different ways to use the posterior density, after the additional cohort is enrolled, to decide whether the MTD is unacceptably toxic.

Continuous infusion of oxaliplatin plus chronomodulated capecitabine in 5-fluorouracil- and irinotecan-resistant advanced colorectal cancer patients

OBJECTIVES

The aim of the study was to define the feasibility and efficacy of Xelox (capecitabine and oxaliplatin) administered through a new and original schedule in advanced pretreated colorectal cancer (CRC) patients.

METHODS

36 metastatic CRC patients resistant at least to a previous 5-fluorouracil- and irinotecan-based chemotherapy line were included in the study.

TREATMENT

Oxaliplatin 70 mg/m2 as continuous infusion for 12 h (8.00 a.m. to 8.00 p.m.) on days 1, 8 plus chronomodulated capecitabine 1,750 mg/m2/day per os (8.00 a.m. 25% of total dose; 6.00 p.m. 25% of total dose; 11.00 p.m. 50% of total dose), on days 1-14 every 21 days. 16 (44.4%) patients had previously received only 1 chemotherapy line for metastatic disease and 20 patients (55.6%) 2 chemotherapy lines. Moreover, 12 patients (33.3%) progressed after a first or second line of oxaliplatin-based regimen as well.

RESULTS

Most frequent related G3-4 adverse reactions were diarrhea (11.6%), nausea/vomiting (8.3%), neuropathy (8.3%), mucositis (8.3%), asthenia (16.7%) and hand-foot syndrome (5.5%). G3-4 anemia, leucopenia and liver toxicities were not observed. The overall response rate was 30.6% (11/36 patients). Disease stabilization was observed in 13 patients (36.1%) and progression in 12 patients (34.3%). Between the 12 oxaliplatin-resistant patients, the overall response rate was 25% (3 patients); 6 patients (54.5%) obtained a stable disease, and only 3 patients (25%) progressed. The median overall survival was 11.3 months (95% confidence interval 7.0-15.7 months), the median response duration 2.8 months (95% confidence interval 1.2-5.6 months) and the median time to progression 6.7 months (95% confidence interval 5.7-6.3 months). The 1-year survival rate was 53.8%.

CONCLUSIONS

The high overall tumor growth control, the remarkable median time to progression and overall survival and the good safety profile are of particular interest for patients with heavy pretreated metastatic CRC.

Efficacy of Treatment with Irinotecan and Oxaliplatin Combination in FU-Resistant Metastatic Colorectal Cancer Patients

OBJECTIVES

As single agents, irinotecan and oxaliplatin are active in colorectal cancer after fluorouracil (FU)-containing regimen failure. Their synergistic activity and non-overlapping toxicity profile are well documented, but more data are needed to explore their exact sequence. The aim of this study was to evaluate the activity and tolerability of irinotecan followed by oxaliplatin in patients with FU-resistant colorectal cancer.

METHODS

FU resistance was defined as disease progression during or within 6 months of discontinuing first-line or adjuvant FU/leucovorin chemotherapy. The study treatment consisted of irinotecan 150 mg/m(2) on days 1 and 8 followed by oxaliplatin 85 mg/m(2) on day 1 every 3 weeks. In order to improve the safety profile, we changed the schedule during the study to irinotecan 300 mg/m(2) on day 1 and oxaliplatin 85 mg/m(2) on day 2 every 3 weeks.

RESULTS

Of 54 patients treated, the 45 patients with measurable disease were assessed in the efficacy analysis, whereas all patients receiving at least one cycle were evaluated in the safety analysis. Of the patients assessed for efficacy analysis, 19 cases received the first schedule and 26 patients received the second schedule. Twenty-two patients (49%) responded, 10 of the first schedule and 12 of the second schedule group. Stable disease was observed in 35% of all patients. The median response duration was 6.5 months (range 3-10), the median time to progression was 8 months (range 6-10), and the overall survival was 15 months (10-26+). The NCI-CTC grade 3 side effects documented in all of the treated patients were: nausea/vomiting (11%), diarrhea (18%), and neutropenia (7%); grade 4 diarrhea was observed in 2% of patients.

CONCLUSION

The combination of irinotecan followed by oxaliplatin combination is well tolerated and highly active in FU-resistant metastatic colorectal cancer patients.

Development of new agents for the treatment of advanced colorectal cancer

During the past decade, there have been several significant advances in the treatment of metastatic colorectal cancer. These include the introduction of the cytotoxic agents capecitabine, irinotecan, and oxaliplatin. Given their diverse mechanisms of action and toxicity profiles, combinations of fluoropyrimidines, irinotecan, and oxaliplatin have proven feasible and have improved patient outcomes compared with 5-fluorouracil alone. Recently, improved understanding of the biology of colorectal cancer has led to the identification of new molecular targets and the development of pharmacologic agents that hold promise for greater tumor selectivity than traditional cytotoxic agents. Two approaches with early indications of clinical activity against colorectal cancer are inhibition of epidermal growth factor receptor signaling and inhibition of the vascular endothelial growth factor pathway. Furthermore, biochemical and genetic profiling of individual tumors, as well as patient genotyping, may ultimately guide clinicians in making rational treatment decisions based on predicted antitumor efficacy or toxicity of selected agents. This article reviews these recent advances in the systemic treatment of colorectal cancer, including discussion of promising agents in clinical development.

Phase I and pharmacokinetic study of two different schedules of oxaliplatin, irinotecan, Fluorouracil, and leucovorin in patients with solid tumors

PURPOSE

We sought to determine the maximum-tolerated dose (MTD) and evaluate the toxicities and clinical activity of two irinotecan (CPT-11), fluorouracil (FU), leucovorin (LV), and oxaliplatin schedules in patients with advanced solid tumors. Additionally, we investigated the effect of CPT-11 on oxaliplatin pharmacokinetics.

PATIENTS AND METHODS

Thirteen patients (cohort 1) received intravenous CPT-11 (infusion) and FU/LV (bolus) on days 1, 8, 15, and 22 and oxaliplatin (infusion) on days 1 and 15 every 6 weeks for a total 37 courses (median, three courses) at three dose levels. Twenty-two cohort 2 patients received intravenous CPT-11/oxaliplatin (infusion, day 1) and FU/LV (90-minute bolus infusion, days 2 to 5) every 3 weeks for a total of 122 courses (median, four courses) at three dose levels. Pharmacokinetic and neurotoxicity assessments were performed at the cohort 2 MTD.

RESULTS

Dose-limiting toxicity (DLT) seen in both cohorts at the starting dose required dose de-escalation. Cohort 1 DLT included diarrhea and neutropenia. In cohort 2, diarrhea, vomiting, dehydration, neutropenia, febrile neutropenia, and paresthesias were DLTs. Antitumor activity was seen in both cohorts. In cohort 2, the total platinum area under the curve of patients increased 17% in cycle 2 (P =.048), but objective neurotoxicity was not seen.

CONCLUSION

The toxicities resulting from the addition of oxaliplatin to CPT-11/FU/LV are significant but manageable. The MTDs for the weekly schedule are CPT-11 (75 mg/m2), oxaliplatin (50 mg/m2), FU (320 mg/m2), and LV (20 mg/m2); and, for the 3-weekly schedule, the MTDs are CPT-11 (175 mg/m2), oxaliplatin (85 mg/m2), FU (240 mg/m2), and LV (20 mg/m2). Second-cycle platinum accumulation raises the possibility for enhanced cumulative neurotoxicity with CPT-11/oxaliplatin combinations.