UGT1A1 genotype-guided dosing of irinotecan: A prospective safety and cost analysis in poor metaboliser patients.

AIM: To determine the safety, feasibility, pharmacokinetics, and cost of UGT1A1 genotype-guided dosing of irinotecan. PATIENTS AND METHODS: In this prospective, multicentre, non-randomised study, patients intended for treatment with irinotecan were pre-therapeutically genotyped for UGT1A1∗28 and UGT1A1∗93. Homozygous variant carriers (UGT1A1 poor metabolisers; PMs) received an initial 30% dose reduction. The primary endpoint was incidence of febrile neutropenia in the first two cycles of treatment. Toxicity in UGT1A1 PMs was compared to a historical cohort of UGT1A1 PMs treated with full dose therapy, and to UGT1A1 non-PMs treated with full dose therapy in the current study. Secondary endpoints were pharmacokinetics, feasibility, and costs. RESULTS: Of the 350 evaluable patients, 31 (8.9%) patients were UGT1A1 PM and received a median 30% dose reduction. The incidence of febrile neutropenia in this group was 6.5% compared to 24% in historical UGT1A1 PMs (P = 0.04) and was comparable to the incidence in UGT1A1 non-PMs treated with full dose therapy. Systemic exposure of SN-38 of reduced dosing in UGT1A1 PMs was still slightly higher compared to a standard-dosed irinotecan patient cohort (difference: +32%). Cost analysis showed that genotype-guided dosing was cost-saving with a cost reduction of €183 per patient. CONCLUSION: UGT1A1 genotype-guided dosing significantly reduces the incidence of febrile neutropenia in UGT1A1 PM patients treated with irinotecan, results in a therapeutically effective systemic drug exposure, and is cost-saving. Therefore, UGT1A1 genotype-guided dosing of irinotecan should be considered standard of care in order to improve individual patient safety.

Cost-effectiveness analysis of UGT1A1*6/*28 genotyping for preventing FOLFIRI-induced severe neutropenia in Chinese colorectal cancer patients.

AIM: To assess the cost-effectiveness of UGT1A1*6/*28 genotyping compared with no genotyping or no dose adjustment before irinotecan administration in China. MATERIALS & METHODS: A decision tree model was developed to evaluate costs and health outcomes represented as quality-adjusted life years gained. Model inputs for the frequency of genotypes, the probability of neutropenia under FOLFIRI chemotherapy and direct costs and utilities were obtained from published sources. One-way sensitivity analyses were performed. RESULTS: The strategy of genotyping with dose reduction dominated all remaining strategies. Compared with the strategies of no genotyping and genotyping with unchanged dose, it resulted in only marginal quality-adjusted life year increases (0.0011 and 0.0012) but a cost reduction of $651.12 and $805.22 per patient, respectively. One-way sensitivity analyses revealed that the model was relatively robust. CONCLUSION: UGT1A1*6/*28 genotyping was cost saving for Chinese colorectal cancer patients.

Assessment of the Applicability of Integrative Tumor Response Assays in Advanced Epithelial Ovarian Cancer.

AIM: To prospectively correlate clinical responses to second-line chemotherapy for recurrent epithelial ovarian cancer (EOC) with in vitro integrative tumor-response assay (ITRA) results. PATIENTS AND METHODS: Forty-four patients with advanced EOC were enrolled from 2015-2017 at the Asan Medical Center, Seoul, Korea. ITRA comprised of two sequential histoculture drug response assays (HDRAs) of the tumor tissues. The first stage was HDRA with paclitaxel-carboplatin, paclitaxel, and carboplatin chemotherapy. The second stage was performed with surviving tumor cells from the first stage using topotecan, belotecan, gemcitabine, doxorubicin, ifosfamide, vinorelbine, and etoposide. RESULTS: The median follow-up period was 23.35 (range=4-35.35) months. Eighteen patients (40.9%) completed the second-line chemotherapy, based on the ITRA results. The objective response rate was 38.9%. The clinical response rate was 50%; two patients (11.1%) had stable disease. The sensitivity of ITRA for predicting response was 85.7% (specificity=18.2%; accuracy=44.44%). CONCLUSION: ITRAs had acceptable applicability and may help choose second-line chemotherapy for patients with advanced EOC.

[Chemotherapy for colorectal cancer: Pragmatic assessment of prescription changes and relative dose intensity]. / Chimiothérapies dans le cancer colorectal : étude pragmatique des modifications de prescription et de dose intensité.

INTRODUCTION: Chemotherapy induced toxicities can generate changes in prescribing and relative dose intensity which have an impact on therapeutic efficacy. METHOD: This is a prospective observational study performed in hepato-gastroenterology department for 6 months. All patients treated for colorectal cancer and beginning a protocol with at least one parenteral drug have been included. RESULTS: Among the 48 patients enrolled, 85.4% of them had at least one prescription change, which concerned 30.3% of 238 cycles. Of the 766 analyzed prescription lines, 16.6% of them were postponed and/or 6.7% had modified dosage and/or 5.6% were stopped prematurely. Grades 2 to 4 adverse reactions were responsible for at least one change prescribing to 64.6% of patients and 17.6% of cycles. Toxicity induced prescription changes were mainly due to clinical toxicities (79.3%). The rate of patients with a relative dose intensity greater than 70% was 92.9% in adjuvant state, 66.7% and 62.5% in metastatic state first line and second and subsequent line. CONCLUSION: High-grade clinical toxicities are the main chemotherapy prescription change pattern in colorectal cancer. Knowledge of toxicities before the patient's arrival is expected to target patients for which the drug preparation can be anticipated and for which a cycle postponement, dose adjustment or discontinuation is necessary.

Comparison of treatment patterns, resource utilization, and cost of care in patients with metastatic pancreatic cancer treated with first-line nab-paclitaxel plus gemcitabine or FOLFIRINOX.

BACKGROUND: We compared real-world treatment patterns, resource utilization, and cost of care for patients with metastatic pancreatic cancer treated with first-line nab-paclitaxel + gemcitabine or FOLFIRINOX (5-fluorouracil, leucovorin, irinotecan, oxaliplatin). METHODS: This was a retrospective study of inpatient and hospital-based outpatient data in the United States. Primary endpoints included median time to treatment discontinuation (TTD) and total cost of care per patient per month. Secondary endpoints included supportive care costs and hospitalization rate and length. RESULTS: Overall, 345 patients were included (nab-paclitaxel + gemcitabine, n = 182; FOLFIRINOX, n = 163). Median TTD was significantly longer with nab-paclitaxel + gemcitabine vs FOLFIRINOX (4.3 vs 2.8 months; P = .0009). Mean acquisition cost was higher with nab-paclitaxel + gemcitabine ($10,643 vs $6549; P = .0043), but mean total cost of care was lower ($16,628 vs $19,936; P = .1740). Supportive care cost was significantly lower with nab-paclitaxel + gemcitabine ($1995 vs $6456; P < .0001). Hospitalization rate and length were both significantly lower with nab-paclitaxel + gemcitabine. CONCLUSIONS: Despite higher acquisition costs with nab-paclitaxel + gemcitabine, FOLFIRINOX-treated patients had higher total costs driven by supportive care. Toxicity-related costs and drug acquisition costs should be considered when evaluating total cost of care.

Time-Series Modeling and Simulation for Comparative Cost-Effective Analysis in Cancer Chemotherapy: An Application to Platinum-Based Regimens for Advanced Non-small Cell Lung Cancer.

The purpose of this study was to propose a time-series modeling and simulation (M&S) strategy for probabilistic cost-effective analysis in cancer chemotherapy using a Monte-Carlo method based on data available from the literature. The simulation included the cost for chemotherapy, for pharmaceutical care for adverse events (AEs) and other medical costs. As an application example, we describe the analysis for the comparison of four regimens, cisplatin plus irinotecan, carboplatin plus paclitaxel, cisplatin plus gemcitabine (GP), and cisplatin plus vinorelbine, for advanced non-small cell lung cancer. The factors, drug efficacy explained by overall survival or time to treatment failure, frequency and severity of AEs, utility value of AEs to determine QOL, the drugs' and other medical costs in Japan, were included in the model. The simulation was performed and quality adjusted life years (QALY) and incremental cost-effectiveness ratios (ICER) were calculated. An index, percentage of superiority (%SUP) which is the rate of the increased cost vs. QALY-gained plots within the area of positive QALY-gained and also below some threshold values of the ICER, was calculated as functions of threshold values of the ICER. An M&S process was developed, and for the simulation example, the GP regimen was the most cost-effective, in case of threshold values of the ICER=$70000/year, the %SUP for the GP are more than 50%. We developed an M&S process for probabilistic cost-effective analysis, this method would be useful for decision-making in choosing a cancer chemotherapy regimen in terms of pharmacoeconomic.

Cost Evaluation of Irinotecan-Related Toxicities Associated With the UGT1A1*28 Patient Genotype.

The adoption of a preemptive UGT1A1*28 genotyping to increase irinotecan safety in clinical practice is still limited. This is the first actual study of costs associated with the management of irinotecan-related toxicities, and their association with UGT1A1*28 genotype. A retrospective analysis of the cost of toxicity management was conducted on 243 metastatic colorectal cancer patients enrolled in a clinical trial and treated with standard of care FOLFIRI (5-fluorouracil combined with irinotecan). The mean predicted cost per patient was higher for *28/*28 (€4,886), vs. *1/*1 (€812), (regression coefficient 1.79, 95% confidence interval (CI) = 1.31-2.28; P < 0.001) and for *1/*28 (€1,119) vs. *1/*1 (regression coefficient 0.32, 95% CI = 0.04-0.60; P = 0.024). This is consistent with a different grade 4 toxicity profile among the three genotypes, and a higher frequency of costly interventions like hospitalization among patients with the *28 allele. A differential toxicity management cost by *28 genotype is herein demonstrated, representing a first step towards the demonstration of the test clinical utility.

Longitudinal adverse event assessment in oncology clinical trials: the Toxicity over Time (ToxT) analysis of Alliance trials NCCTG N9741 and 979254.

BACKGROUND: Traditional methods of reporting adverse events in clinical trials are inadequate for modern cancer treatments with chronic administration. Conventional analysis and display of maximum grade adverse events do not capture toxicity profiles that evolve over time or longer lasting, lower grade toxic effects; we aimed to address this shortcoming in this study. METHODS: We developed an analytic approach and standardised, comprehensive format, the Toxicity over Time (ToxT) approach, which combines graphs and adverse event tabular displays with multiple longitudinal statistical techniques into a readily applicable method to study toxic effects. Plots visualising summary statistics or individual patient data over discrete timepoints were combined with statistical methods including the following longitudinal techniques: repeated measures models that describe the changes in adverse events across all cycles of treatment; time-to-event analyses of first and worst grade toxicity; and area under the curve (AUC) analyses summarising adverse event profiles over the entire course of a study, including chronic low-grade events. We applied ToxT analysis to adverse event data from two completed North Central Cancer Treatment Group (NCCTG/Alliance) trials: N9741 (NCT00003594), in which different combinations of oxaliplatin, 5-fluorouracil, and irinotecan were investigated for metastatic colorectal cancer, and 979254, in which survivors of breast cancer were given venlafaxine or placebo for control of hot flashes. FINDINGS: In trial NCCTG 979254 there was a higher incidence of late-occurring dry mouth in patients who were given venlafaxine than in those given placebo (week 1 [baseline]: 13% [six incidence in 48 patients, SD 5] vs 22% [11/49, SD 6]; p=0·20; week 5: 49% [24/49, 7] vs 2% [1/46, 2]; p<0·0001). In trial NCCTG N9741 there was an increased incidence of early nausea for patients given irinotecan plus oxaliplatin (IROX) compared with those given 5-fluorouracil plus oxaliplatin (FOLFOX; cycle 1 mean grade nausea 1·1 [SD 1·0] vs 0·6 [0·7]; p<0·0001). Event charts showed earlier occurrences of higher grades of diarrhoea for patients given IROX compared with those given FOLFOX, and the AUC analysis shows a higher magnitude of diarrhoea consistently over time throughout the study in patients given IROX versus those given FOLFOX (mean AUC 4·2 [SD 5·2] vs 2·9 [4·2]; p<0·0001). INTERPRETATION: The ToxT analytical approach incorporates the dimension of time into adverse event assessment and offers a more comprehensive depiction of toxic effects than present methods. With new, continuously administered targeted agents, immunotherapy, and maintenance regimens, these improved longitudinal analyses are directly relevant to patients and are crucial in cancer clinical trials. FUNDING: National Cancer Institute of the National Institutes of Health and the Mayo Comprehensive Cancer Center.

Modified irinotecan and infusional 5-fluorouracil (mFOLFIRI) in patients with refractory advanced pancreas cancer (APC): a single-institution experience.

Pancreatic adenocarcinoma is the fourth leading cause of cancer death. Recently, MM-398 (nanoliposomal irinotecan) was shown to be associated with significant improvement in outcome measures with acceptable toxicities when combined with 5-fluorouracil (5-FU)/leucovorin (LV) compared to 5-FU/LV alone in patients failing one line of gemcitabine-based therapy. There is a paucity of data evaluating the role of irinotecan in combination with 5FU in advanced pancreas cancer (APC). We performed a retrospective analysis of all patients who received mFOLFIRI (minus bolus 5FU and LV). All patients with metastatic disease who had failed at least one line of gemcitabine-based therapy prior to receiving mFOLFIRI were included in this study. Descriptive statistics were used to assess the continuous variables and adverse events (AEs), and Kaplan-Meier methods were used to calculate the median progression-free survival (PFS) and overall survival (OS). Forty patients were included in this analysis. Patients received 1-5 lines of prior therapy (25 % with more than 3 lines of prior therapy). The mean age at diagnosis was 60, and 98 % had ECOG of 1. The mean CA 19-9 at the start of therapy was 33,169 U/ml. The median PFS was 2.59 months [95 % confidence interval (CI) (1.90, 3.54)], and OS was 4.75 months [95 % CI (3.14, 8.98)]. The most common AEs included fatigue (98 %), neuropathy (83 %), anorexia (68 %), nausea (60 %) and constipation (55 %). Grade 3 toxicities included fatigue (13 %) and rash (3 %). There were no observed grade 4 toxicities. In this single-institution retrospective analysis, mFOLFIRI was found to be both tolerable and relatively effective in a heavily pretreated patient population with APC. Future prospective studies should consider evaluating the role of mFOLFIRI in refractory APC.

Transarterial hepatic chemoembolization with 70-150 µm drug-eluting beads: assessment of clinical safety and liver toxicity profile.

PURPOSE: To assess the incidence and severity of adverse events (AEs) in the form of clinical symptoms and liver/biliary injuries (LBI) in patients with hepatic malignancies treated with transarterial chemoembolization using 70-150 µm drug-eluting beads (DEBs). MATERIALS AND METHODS: A single-institution retrospective analysis was performed in 37 patients (25 patients with hepatocellular carcinoma and 12 patients with metastatic disease) who underwent 43 sessions of segmental/subsegmental 70-150 µm DEB transarterial chemoembolization with doxorubicin (38 sessions) or irinotecan (5 sessions). Patient inclusion criteria included the presence of the following lesion features: small diameter (≤ 3 cm), hypovascular, or with areas of residual disease after other locoregional therapies. Mean tumor diameter was 3.4 cm. Mean imaging and clinical follow-up periods were 171 days and 373 days, respectively. Clinical, laboratory, and imaging data were used to identify and classify clinically symptomatic AEs per session and LBI per patient according to the National Cancer Institute Common Terminology Criteria for Adverse Events, version 4.03. Predictors for the occurrence of LBI were evaluated by logistic regression analysis. RESULTS: No grade 4 or 5 AEs were recorded. Clinically symptomatic AEs occurred in 29 (67.4%) sessions (grade 1-2, 28 sessions; grade 3, 1 session), all constituting postembolization syndrome. Asymptomatic LBI occurred in 11 (29.7%) patients (grade 1, 8 patients; grade 2, 3 patients). The mean time between 70-150 µm DEB transarterial chemoembolization session and appearance of LBI was 71 days (range, 21-223 d). No predictive factors for the development of LBI were identified. CONCLUSIONS: Transarterial chemoembolization with 70-150 µm DEBs was considered safe in the present study population given the acceptably low incidence and severity of AEs.

The Clinical and Cost Effectiveness of Aflibercept in Combination with Irinotecan and Fluorouracil-Based Therapy (FOLFIRI) for the Treatment of Metastatic Colorectal Cancer Which has Progressed Following Prior Oxaliplatin-Based Chemotherapy: a Critique of the Evidence.

The National Institute for Health and Care Excellence (NICE) invited the manufacturer of aflibercept (Sanofi) to submit clinical and cost-effectiveness evidence for aflibercept in combination with irinotecan and fluorouracil-based therapy [irinotecan/5-fluorouracil/folinic acid (FOLFIRI)] for the treatment of metastatic colorectal cancer which has progressed following prior oxaliplatin-based chemotherapy, as part of the Institute's Single Technology Appraisal process. The Centre for Reviews and Dissemination and Centre for Health Economics at the University of York were commissioned to act as the independent Evidence Review Group (ERG). This article provides a description of the company submission, the ERG review and the resulting NICE guidance TA307 issued in March 2014. The ERG critically reviewed the evidence presented in the manufacturer's submission and identified areas requiring clarification, for which the manufacturer provided additional evidence. The clinical effectiveness data were derived from one good-quality double-blind randomised controlled trial (RCT), the VELOUR trial, which compared aflibercept plus FOLFIRI with placebo plus FOLFIRI. This RCT found a small but statistically significant increase in overall survival (OS); the difference in median OS was 1.44 months (13.5 months in the aflibercept group and 12.06 months in the placebo group). There was also a statistically significant increase in progression-free survival (PFS) with aflibercept; the difference in median PFS was 2.23 months (6.9 months in the aflibercept group and 4.67 months in the placebo group). However, grade 3-4 adverse events were more frequent in the aflibercept group than the placebo group: 83.5% compared with 62.5%. Treatment-emergent adverse events led to permanent discontinuation of treatment in 26.8% of patients in the aflibercept group and 12.1% of patients in the placebo group. The manufacturer's submission included an estimation of mean OS benefit based on extrapolation of the data, which was considerably longer than the median OS benefit reported (4.7 vs. 1.44 months). The ERG considered this to be an over estimate. The base-case incremental cost-effectiveness ratio (ICER) for the overall population was reported by the manufacturer to be £36,294 per quality-adjusted life-year (QALY). After correcting the model programming and updating the model to include the ERG's preferred parameter estimates, the ICER from the ERG's alternative base case was £54,368 per QALY. The extrapolation of the OS curves was the key cost-effectiveness driver and a major source of uncertainty in the model. Additional scenarios related to the extrapolation of OS undertaken by the ERG resulted in ICERs between £62,894 and £92,089 per QALY. After consideration of the manufacturer's submission and the ERG's critique, and submissions from other stakeholders, the NICE Appraisal Committee concluded that aflibercept in combination with irinotecan and fluorouracil-based therapy could not be considered a cost effective use of National Health Service resources for treating metastatic colorectal cancer that is resistant to or has progressed after an oxaliplatin-containing regimen. Aflibercept in combination with irinotecan and fluorouracil-based therapy is not recommended for the treatment of metastatic colorectal cancer that is resistant to or has progressed after an oxaliplatin-containing regimen in NICE guidance TA307.

[Monitoring and evaluation tools for irinotecan and bevacizumab in glioblastoma: from prescription to patient's information]. / Outils de suivi et d'autoévaluation de l'irinotécan et du bévacizumab dans les glioblastomes : de la prescription à l'information du patient.

In 2007, the use of a new therapeutic association that included two expensive drugs (bevacizumab and irinotecan), used in second line treatment for progressive glioblastoma, led to the increase of the monitoring and self-evaluation of the medical prescriptions. Methodological tools have been designed by neuro-oncologists together with pharmacists of the Pitié-Salpêtrière Hospital in order to be consistent with the "good use economic contract". Those drugs have not been approved by European authorities in this indication and, moreover, this combination presents adverse effects and contraindications that need to be known by the professionals, the patient and his family. Some documents have been created in order to facilitate prescriptions for neuro-oncologists and others provide monitoring tools for the physicians and nurses. A letter of information targets the patient and his family, another one targets the general practitioner. This is useful for a better coordination between these ones and the hospital. The patient receives a document and a monitoring book in order to inform him about his treatment and help him to prevent and react in time in case of side effects occurrence. Those measures have been designed to put a frame around the prescriptions and to decrease iatrogenic events as well as the economic costs.

A systematic review of FOLFOXIRI chemotherapy for the first-line treatment of metastatic colorectal cancer: improved efficacy at the cost of increased toxicity.

AIM: The simultaneous administration of irinotecan, 5-fluorouracil, folinic acid and oxaliplatin (FOLFOXIRI) has been compared with standard 5-fluorouracil, folinic acid and irinotecan (FOLFIRI) in randomized trials in metastatic colorectal cancer patients. A superior efficacy of FOLFOXIRI has been reported by some authors, but others have failed to show any differences and do not recommend its use because of greater cost and toxicity. We performed a systematic review of the literature to analyse efficacy and toxicity of FOLFOXIRI. METHOD: Odds ratios (OR) with 95% confidence intervals (CI) were used to analyse dichotomous variables. Hazard ratios (HR) for progression and death were combined with an inverse variance method based on logarithmic conversion. A fixed-effect model and Mantel-Haenszel's method were used. Heterogeneity was tested with Cochrane's Q test and I(2) test. RESULTS: A significant increase in response rate (OR 2.04; P < 0.01) was associated with treatment by FOLFOXIRI and a benefit was also shown by the HR for progression (HR 0.72; P < 0.01) and death (HR 0.71; P < 0.01). Analysis for toxicity found a significant increase associated with FOLFOXIRI except for anaemia, fatigue and febrile neutropenia. CONCLUSION: FOLFOXIRI confers significant benefit in progression-free survival, survival, response and R0 resection rates but is more toxic compared with FOLFIRI.

Understanding chemotherapy treatment pathways of advanced colorectal cancer patients to inform an economic evaluation in the United Kingdom.

BACKGROUND: Accurate description of current practice within advanced colorectal cancer (CRC) specialties were needed to inform an economic evaluation of the UGT1A1 pharmacogenetic test for irinotecan in the United Kingdom. METHODS: The study was based on a literature review and elicitation of expert opinion. The expert panel comprised 44 consultant oncologists in NHS Hospital Trusts across England. RESULTS: Ten first-line, 10 second-line and 12 third-line chemotherapy regimens were reported, reflecting wide variations in treatment pathways. Predominant pathways emerged with: first-line treatment with oxaliplatin-based regimens, second-line treatment with irinotecan-based regimens and third-line treatment with mitomycin-based regimens. Experts estimated the frequency of febrile neutropaenia 8.4% (95% CI: 6.7-10.0), septic neutropaenia 4.7% (95% CI: 3.4-6.0) and severe diarrhoea 13.1% (95% CI: 10.8-15.5). Approaches for the clinical management of neutropaenia within the NHS were described. CONCLUSIONS: This study identified wide variations in the clinical management of advanced CRC patients. Descriptions of current treatment pathways are necessary for economic evaluations. Variations in clinical practice must be reflected in the model to ensure the findings from an economic evaluation of UGT1A1 testing are sufficient to inform policy regarding the cost-effective use of NHS resources.

Clinical and economic evaluation of first-line therapy with FOLFIRI or modified FOLFOX6 for metastatic colorectal cancer.

OBJECTIVE: Recently, significant progress in treatment of metastatic colorectal cancer has been achieved. Either FOLFIRI (fluorouracil, leucovorin and irinotecan) or modified FOLFOX6 (fluorouracil, leucovorin and oxaliplatin, oxaliplatin dose 85 mg/m(2)) is selected as first-line therapy in clinical practice in Japan. However, economic burden of colorectal cancer is considerable. METHODS: Analysis was made for all patients who were treated with FOLFIRI or modified FOLFOX6 for metastatic colorectal cancer. Regimen of FOLFIRI was compared with modified FOLFOX6 under consideration from clinical and economic standpoints. Progression free survival, response, toxicity and cancer care cost in patients with metastatic colorectal cancer was analyzed. Direct costs based on the fee schedule of the Japanese national health insurance were calculated. RESULTS: Median progression free survival was 7.7 months for FOLFIRI versus 8.4 months for modified FOLFOX6 (P = 0.48). Overall cost for first four cycles was yen756 284 for FOLFIRI and yen1 081 162 for modified FOLFOX6 (P < 0.0001). All grade alopecia was significantly more frequent with FOLFIRI than with modified FOLFOX6 (P = 0.04). All grade neuropathy was more observed with modified FOLFOX6 than FOLFIRI (P = 0.0002). CONCLUSIONS: FOLFIRI is inexpensive in the initial stage of treatment which a number of patients can receive chemotherapy than modified FOLFOX6 as first-line therapy for metastatic colorectal cancer in Japanese national insurance system.

Pharmacogenetic assessment of toxicity and outcome in patients with metastatic colorectal cancer treated with LV5FU2, FOLFOX, and FOLFIRI: FFCD 2000-05.

PURPOSE: The aim was to investigate whether germline polymorphisms within candidate genes known or suspected to be involved in fluorouracil (FU), oxaliplatin, and irinotecan pathways were associated with toxicity and clinical outcome in patients with metastatic colorectal cancer (mCRC). PATIENTS AND METHODS: Blood samples from 349 patients included in the Fédération Francophone de Cancérologie Digestive 2000-05 randomized trial, which compared FU plus leucovorin (LV5FU2) followed by FU, leucovorin, and oxaliplatin (FOLFOX) followed by FU, leucovorin, and irinotecan (FOLFIRI; sequential arm) with FOLFOX followed by FOLFIRI (combination arm) in terms of progression-free survival (PFS) and overall survival, were collected. Twenty polymorphisms within the DPD, TS, MTHFR, ERCC1, ERCC2, GSTP1, GSTM1, GSTT1, and UGT1A1 genes were genotyped. RESULTS: The ERCC2-K751QC allele was independently associated with an increased risk of FOLFOX-induced grade 3 or 4 hematologic toxicity (P = .01). In the sequential arm, TS-5'UTR3RG and GSTT1 alleles were independently associated with response to LV5FU2 (P = .009) and FOLFOX (P = .01), respectively. The effect of oxaliplatin on tumor response increased with the number of MTHFR-1298C alleles (test for trend, P = .008). The PFS benefit from first-line FOLFOX was restricted to patients with 2R/2R (hazard ratio [HR] = 0.39; 95% CI, 0.23 to 0.68) or 2R/3R (HR = 0.59; 95% CI, 0.42 to 0.82) TS-5'UTR genotypes, respectively. Conversely, patients with the TS-5'UTR 3R/3R genotype did not seem to benefit from the adjunction of oxaliplatin (HR = 0.96; 95% CI, 0.66 to 1.40; trend between the three HRs, P = .006). CONCLUSION: A pharmacogenetic approach may be a useful strategy for personalizing and optimizing chemotherapy in mCRC patients and deserves confirmation in additional prospective studies.

Cost-effectiveness of UGT1A1*28 genotyping in preventing severe neutropenia following FOLFIRI therapy in colorectal cancer.

PURPOSE: Functional polymorphisms of the UGT1A1 gene, particularly the UGT1A1*28 variant, are associated with the severity of the bone marrow suppression in patients with metastatic colorectal cancer receiving irinotecan. This study assesses the cost-effectiveness of screening for UGT1A1*28 polymorphism associated with primary prophylactic Granulocytes Colony Stimulating Factor in patients homozygous for the *28 allele. The effectiveness was estimated based on the number of neutropenia avoided. METHODS: We modelled a theoretical population treated with combined 5-fluorouracil, leucovorin and irinotecan (FOLFIRI) for metastatic colorectal cancer. A decision tree simulated the health outcomes, measured by the prevalence of neutropenic events for two strategies, with or without UGT1A1 genotype screening. The model incorporated direct hospital costs and was validated with a sensitivity analysis. We calculated the cost-effectiveness ratio: CE=∆C / ∆E = "genotyping" cost - "no genotyping" cost / number of febrile neutropenia avoided. RESULTS: In the "genotyping strategy", the cost to avoid one febrile neutropenia event per 1000 patients treated was € 942.8 to € 1090.1. The sensitivity analysis showed a better CE ratio of € 733.4 to € 726.6 per febrile neutropenic event avoided. CONCLUSIONS: UGT1A1 genotype screening before irinotecan treatment is a cost-efficient strategy for the hospital. Systematic genotyping prior to chemotherapy, and administration of CSF in patients homozygotes for the *28 allele allow to avoid 91 febrile neutropenias at an acceptable cost.

Cost effectiveness of pharmacogenetic testing for uridine diphosphate glucuronosyltransferase 1A1 before irinotecan administration for metastatic colorectal cancer.

BACKGROUND: The objective of this study was to examine the cost effectiveness of using a pharmacogenetic test for uridine diphosphate glycosyltransferase 1A1*28 (UGT1A1*28) variant homozygosity before administering irinotecan to patients with metastatic colorectal cancer. METHODS: A decision-analytic model from the Medicare payer perspective followed hypothetical patients who were treated with combined 5-fluorouracil, leucovorin, and irinotecan. Under usual care, patients received a full dose of irinotecan. With genetic testing, irinotecan dosage was reduced 25% in homozygotes with the UGT1A1*28 variant allele. Test performance, chemotherapy toxicity, and quality-of-life weights were derived from clinical literature and product labels, and costs were derived from 2007 Medicare fee schedules. Chemotherapy efficacy after dose reduction, adverse event risk, and other parameters were varied in 1-way and probabilistic sensitivity analyses. The authors also calculated the value of investing in further studies of chemotherapy efficacy after homozygote dose reductions. RESULTS: Pretreatment genetic testing costs less ($272 savings per patient tested) and yields slightly improved quality-adjusted life expectancy (0.1 quality-adjusted day per patient tested; approximately 2 quality-adjusted hours). Results depended on treatment efficacy but not adverse event risk assumptions. The results indicated that testing would avoid 84 cases of severe neutropenia, including 4.4 deaths. At a threshold of $100,000 per quality-adjusted life year, the therapeutic efficacy of irinotecan in homozygotes after dose reduction had to be > or =98.4% of full-dose efficacy for genetic testing to remain preferred. Future studies to determine whether this efficacy level can be achieved have an economic value of $22 million. CONCLUSIONS: The current results indicated that pharmacogenetic testing for UGT1A1*28 variant homozygosity may be cost effective, but only if irinotecan dose reduction in homozygotes does not reduce efficacy. Future studies to evaluate reduced-dose efficacy in homozygotes should be considered.

The use of irinotecan, oxaliplatin and raltitrexed for the treatment of advanced colorectal cancer: systematic review and economic evaluation.

OBJECTIVES: To evaluate three technologies for the management of advanced colorectal cancer: (1) first-line irinotecan combination [with 5-fluorouracil (5-FU)] or second-line monotherapy; (2) first- or second-line oxaliplatin combination (again, with 5-FU); and (3) raltitrexed, where 5-FU is inappropriate. To examine the role of irinotecan and oxaliplatin in reducing the extent of incurable disease before curative surgery (downstaging). SOURCES: Ten electronic bibliographic databases covering the period up to August 2004. METHODS: Searches identified existing studies of the effectiveness and economics of the technologies and any studies that evaluated any of the indications outlined above were included. Data were extracted and assessed generic components of methodological quality. Survival outcomes were meta-analysed. RESULTS: Seventeen trials were found, of varying methodological quality. Compared with 5-FU, first-line irinotecan improved overall survival (OS) by 2-4 months (p=0.0007), progression-free survival (PFS) by 2-3 months (p<0.00001) and response rates (p<0.001). It offered a different toxicity profile and no quality of life (QoL) advantage. However, second-line irinotecan compared with 5-FU improved OS by 2 months (p=0.035) and PFS by 1 month (p=0.03), and provided a better partial response rate, but with more toxicities and no QoL advantage. Compared with second-line best supportive care, irinotecan improved OS by 2 months (p=0.0001), had a different toxicity profile and maintained baseline QoL longer, but with no overall difference. The addition of oxaliplatin to second-line 5-FU is associated with a borderline significant improvement in overall survival (p<0.07); a significantly higher response rate (<0.0001); and more serious toxicities. There is no evidence for a significant difference in QoL. Schedules with treatment breaks may not reduce clinical effectiveness but reduce toxicity. The addition of oxaliplatin to second-line 5-FU also saw no improvement in OS (p<0.07), better PFS (by 2.1 months, p=0.0001), an 8.9% higher response rate (p<0.0001), more toxicities and no QoL advantage. There was no significant difference in OS or PFS between first-line irinotecan and oxaliplatin combinations except when 5-FU was delivered by bolus injection, when oxaliplatin provided better OS (p=0.032) and response rates (p=0.032), but not PFS (p=0.169). The regimens had different toxicity profiles and neither conferred a QoL advantage. When compared to 5-FU, raltitrexed is associated with no significant difference in overall or progression-free survival; no significant difference in response rates; more vomiting and nausea, but less diarrhoea and mucositis; no significant difference in, or worse QoL. Raltitrexed treatment was cut short in two out of four included trials due to excess toxic deaths. 5-FU followed by irinotecan was inferior to any other sequence. First-line irinotecan/5-FU combination improved OS and PFS, although further unplanned therapy exaggerated the OS effect size. Staged combination therapy (combination oxaliplatin followed by combination irinotecan or vice versa) provided the best OS and PFS, although there was no head-to-head comparison against other treatment plans. In the only trial to use three active chemotherapies in any staged combination, median OS was over 20 months. In another study, the longest median OS from a treatment plan using two active agents was 16.2 months. Where irinotecan or oxaliplatin were used with 5-FU to downstage people with unresectable liver metastases, studies consistently showed response rates of around 50%. Resection rates ranged from 9 to 35% with irinotecan and from 7 to 51% with oxaliplatin. In the one study that compared the regimens, oxaliplatin enabled more resections (p=0.02). Five-year OS rates of 5-26% and disease-free survival rates of 3-11% were reported in studies using oxaliplatin. Alone or in combination, 5-FU was more effective and less toxic when delivered by continuous infusion. Existing economic models were weak because of the use of unplanned second-line therapies in their trial data: the survival benefits in patients on such trials cannot be uniquely attributed to the allocated therapy. Consequently, the economic analyses are either limited to the use of PES (at best, a surrogate outcome) or are subject to confounding. Weaknesses in cost components, the absence of direct in-trial utility estimates and the limited use of sensitivity analysis were identified. Improvements to the methodologies used in existing economic studies are presented. Using data from two trials that planned treatment sequences, an independent economic evaluation of six plans compared with first-line 5-FU followed on progression by second-line irinotecan monotherapy (NHS standard treatment) is presented. 5-FU followed on progression by irinotecan combination cost 13,174 pounds per life-year gained (LYG) and 10,338 pounds per quality-adjusted life-year (QALY) gained. Irinotecan combination followed on progression by additional second-line therapies was estimated to cost 12,418 pounds per LYG and 13,630 pounds per QALY gained. 5-FU followed on progression by oxaliplatin combination was estimated to cost 23,786 pounds per LYG and 31,556 pounds per QALY gained. Oxaliplatin combination followed on progression by additional second-line therapies was estimated to cost 43,531 pounds per LYG and 67,662 pounds per QALY gained. Evaluations presented in this paragraph should be interpreted with caution owing to missing information on the costs of salvage therapies in the trial from which data were drawn. Irinotecan combination followed on progression by oxaliplatin combination cost 12,761 pounds per LYG and 16,663 pounds per QALY gained. Oxaliplatin combination followed on progression by irinotecan combination cost 16,776 pounds per LYG and 21,845 pounds per QALY gained. The evaluation suggests that these two sequences have a cost-effectiveness profile that is favourable in comparison to other therapies currently funded by the NHS. However, the differences in OS observed between the two trials from which data were taken may be a result of heterogeneous patient populations, unbalanced protocol-driven intensity biases or other differences between underlying health service delivery systems. CONCLUSIONS: Treatment with three active therapies appears most clinically effective and cost-effective. NHS routine data could be used to validate downstaging findings and a meta-analysis using individual patient-level data is suggested to validate the optimal treatment sequence.