Phase II randomised trial of raltitrexed-oxaliplatin vs raltitrexed-irinotecan as first-line treatment in advanced colorectal cancer

Evidence Following Conditional NICE Technology Appraisal Recommendations: A Critical Analysis of Methods, Quality and Risk of Bias

BACKGROUND

The National Institute for Health and Care Excellence (NICE) may approve health technologies on condition of more evidence generated only in research (OiR) or only with research (OwR). NICE specifies the information needed to comply with its request, although it may not necessarily guarantee good quality and timely evidence for re-appraisal, before reaching a final decision.

AIM

This study aimed to critically appraise the methods, quality and risk of bias of evidence generated in response to NICE OiR and OwR technology appraisal (TA) and highly specialised technologies (HSTs) recommendations.

METHODS

NICE TAs (between March 2000 and September 2020) and HST evaluations (to October 2023) of medicines were reviewed. Conditional recommendations were analysed to identify the evidence requested by NICE for re-appraisal. The new evidence was analysed for compliance with NICE's request and assessed using the Cochrane Collaboration's tools for risk of bias in randomised trials and the ROBINS-I tool for non-randomised evidence.

RESULTS

NICE made 54 conditional recommendations from TAs (13 OiR and 41 OwR) and five conditional recommendations for HSTs (all OwR). Of these, 16 TAs presented additional evidence for re-appraisal (9 OiR [69%] and 7 OwR [17%]) and three HSTs (3 OwR [60%]). Two of the nine re-appraised TAs with OiR recommendation and four of the seven OwR complied fully with NICE's request for further evidence, while all three from the HSTs complied. The majority of re-appraised TAs and HSTs included evidence that was deemed to be at serious, high, moderate or unclear risk of bias. Among the 26 randomised controlled trials from TAs assessed, eight were categorised as having low risk of bias in all domains and ten had at least one domain as a high risk of bias. Reporting was unclear for the remainder. Twenty-two non-randomised studies, primarily single-arm studies, were susceptible to biases mostly due to the selection of participants and to confounding. Two HSTs provided evidence from randomised controlled trials which were classified as unclear or high risk of bias. All non-randomised evidence from HSTs were categorised as moderate or serious risk of bias.

CONCLUSIONS

There is widespread non-compliance with agreed data requests and important variation in the quality of evidence submitted in response to NICE conditional approval recommendations. Quality standards ought to be stipulated in respect to evidence contributing to re-appraisals following NICE conditional approval recommendations.

Camptothecin and Its Derivatives from Traditional Chinese Medicine in Combination with Anticancer Therapy Regimens: A Systematic Review and Meta-Analysis

Background/Objectives: Camptothecin (CPT) and its derivatives, irinotecan and topotecan, are integral components of cancer chemotherapy, often used in combination therapies. This meta-analysis evaluates the efficacy of CPT-based combination treatments in cancer patients. Methods: We systematically searched the literature database using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist for articles published between 2000 and 2022. Published studies were retrieved through an electronic search on the Web of Science, PubMed, and Google Scholar databases. A total of 138 studies were downloaded and examined, and 71 eligible studies were selected for meta-analysis after excluding studies that did not meet the inclusion criteria. Results: Ultimately, a total of 71 studies were included in the analysis, comprising non-small cell lung cancer (NSCLC), colorectal cancer (COLRC), oesophageal/gastric cancer (O/GC), and small cell lung cancer (SCLC). For NSCLC, the objective response rate (RR) was 31.8% (95% CI: 27.3-37.1%, p = 0.025), with irinotecan plus cisplatin showing significantly higher efficacy compared to other irinotecan-based combinations. In COLRC, irinotecan and 5-fluorouracil/leucovorin plus bevacizumab demonstrated superior efficacy with a RR of 44% (95% CI: 34-58, p < 0.001) and minimal haematological toxicity. In O/GC, irinotecan-based combinations showed an average RR of 43% (95% CI: 27-70, p < 0.001) and average overall survival (OS) and progression-free survival (PFS) rates of 10.2 and 5.5 months, respectively. For SCLC, irinotecan-based combinations had a higher control response than topotecan-based ones, while the latter exhibited higher rates of stable and progressive disease. The overall RR for SCLC was 45% (95% CI: 34.3-60.2, p < 0.001). Conclusions: The existing evidence underscored the potential of CPT-based combination therapy in various cancers. Among the various combinations discussed in this analysis, irinotecan plus cisplatin demonstrated the highest objective RR in 12 trials focused on NSCLC. This study provides valuable insights into potential treatment strategies for various types of cancer, emphasising the importance of personalised and tailored approaches to maximise efficacy and minimise adverse effects.

A decade's overview of 2-aminothiophenes and their fused analogs as promising anticancer agents

Over the past decades, cancer has been a challenging domain for medicinal chemists as it is an international health concern. In association, small molecules such as 2-aminothiophenes and their derivatives showed significant antitumor activity through variable modes of action. Therefore, this article aims to review the advances regarding these core scaffolds over the past 10 years, where 2-aminothiophenes and their fused analogs are classified and discussed according to their biological activity and mode of action, in the interest of boosting new design pathways for medicinal chemists to develop targeted antitumor candidates.

Raltitrexed Chemotherapy Regimen Plus Bevacizumab as Second-Line Treatment for Metastatic Colorectal Cancer: A Prospective Multicenter Phase II Trial

OBJECTIVES

Clinical studies have shown that bevacizumab plus chemotherapy significantly improves efficacy in metastatic colorectal cancer (mCRC). This prospective study aims to investigate the efficacy and safety of changing second-line treatment to raltitrexed-based chemotherapy regimens plus bevacizumab in mCRC patients who have failed the first-line fluorouracil-based chemotherapy regimen with or without bevacizumab/cetuximab.

METHODS

This is a prospective, open-label, multicenter, phase II clinical study. A total of 100 patients with mCRC after failure of the first-line fluorouracil-based chemotherapy regimen with or without bevacizumab/cetuximab were enrolled from November 2016 to October 2021, and received second-line raltitrexed-based chemotherapy regimen plus bevacizumab. Patients were treated for 6 cycles, and efficacy evaluation over stable disease were followed by maintenance treatment of bevacizumab and raltitrexed until disease progression or intolerable toxicity. The primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS), objective response rate (ORR), disease control rate (DCR), safety, and toxicity.

RESULTS

Ninety-four patients were treated with SALIRI (raltitrexed + irinotecan) plus bevacizumab, and six patients with SALOX (raltitrexed + oxaliplatin) plus bevacizumab. Median PFS was 8.4 (95% CI: 6.2-11.0) months, including 8.2 (95% CI 6.2, 11.0) months in the SALIRI group and 11.6 (95% CI 3.1, NA) months in the SALOX group. Median OS was 17.6 (95% CI 15.2, 22.0) months in the SALIRI group and 17.1 (95% CI 4.1, NA) months in the SALOX group. ORR and DCR were 25.5% and 87.2% in the SALIRI group, and 33.3% and 83.3% in the SALOX group, respectively. A low incidence of grade 3-4 adverse events was observed.

CONCLUSIONS

Raltitrexed-based chemotherapy regimens plus bevacizumab improved survival duration in mCRC patients with failed first-line therapy. Therefore, treatment with raltitrexed-based chemotherapy regimens plus bevacizumab could be a superior therapeutic option for second-line chemotherapy in mCRC (ClinicalTrials.gov registration number: NCT03126071).

Oncological Treatment-Related Fatigue in Oncogeriatrics: A Scoping Review

Fatigue is a highly prevalent symptom in both cancer patients and the older population, and it contributes to quality-of-life impairment. Cancer treatment-related fatigue should thus be included in the risk/benefit assessment when introducing any treatment, but tools are lacking to a priori estimate such risk. This scoping review was designed to report the current evidence regarding the frequency of fatigue for the different treatment regimens proposed for the main cancer indications, with a specific focus on age-specific data, for the following tumors: breast, ovary, prostate, urothelium, colon, lung and lymphoma. Fatigue was most frequently reported using the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE) versions 3 to 5. A total of 324 regimens were analyzed; data on fatigue were available for 217 (67%) of them, and data specific to older patients were available for 35 (11%) of them; recent pivotal trials have generally reported more fatigue grades than older studies, illustrating increasing concern over time. This scoping review presents an easy-to-understand summary that is expected to provide helpful information for shared decisions with patients regarding the anticipation and prevention of fatigue during each cancer treatment.

First-line chemotherapy with raltitrexed in metastatic colorectal cancer: an Association des Gastro-entérologues Oncologues (AGEO) multicentre study

BACKGROUND

In case of contraindication or intolerance to fluoropyrimidines, raltitrexed is a validated alternative in metastatic colorectal cancer (mCRC), associated or not with oxaliplatin. Little is known about the outcomes of raltitrexed combined with irinotecan or targeted therapies.

METHODS

This retrospective multicentre study enroled mCRC patients treated with first-line raltitrexed-based chemotherapy. Treatment-related toxicities were recorded. Progression-free survival (PFS) and overall survival (OS) were calculated from treatment start.

RESULTS

75 patients were treated with raltitrexed alone, TOMOX, or TOMIRI with or without bevacizumab. Grade 3-4 adverse events were seen in 31% of patients, without significant difference between the different treatment schedules. amongst the 36 patients with a history of fluoropyrimidine-induced cardiac toxicity, none developed cardiovascular events on raltitrexed. Median PFS and OS were 10.6 (95% CI 8.2 - 13.1) and 27.4 months (95% CI 24.1-38.1), respectively. Considering the chemotherapy regimen, TOMOX was significantly associated with better PFS and OS compared to TOMIRI and raltitrexed alone.

CONCLUSIONS

In patients with mCRC not eligible for fluoropyrimidines, first-line raltitrexed-based chemotherapy had an acceptable safety profile. PFS and OS were consistent with usual survival data in mCRC, and significantly better in patients treated with TOMOX, independently of associated targeted therapies.

Managing 5FU Cardiotoxicity in Colorectal Cancer Treatment

Fluorouracil (5FU) is the backbone chemotherapy agent in the treatment of colorectal cancer (CRC). Cardiotoxicity represents an uncommon but serious side effect of treatment with 5FU. Here, we review the current literature on 5FU-cardiotoxicity in the setting of CRC specifically, with a focus on data from the modern era of combination chemotherapy. Despite decades of study, there is little consensus on risk factors and biomarkers for 5FU-cardiotoxicity, nor how patients with CRC should be managed following a cardiotoxicity event. Given the elevated risk of recurrent cardiotoxicity on rechallenge, the use of alternative regimens that do not contain 5FU is a critical aspect of management. Data on the cardiotoxicity risk and efficacy of non-5FU regimens in CRC are therefore reviewed in detail.

Comparison of irinotecan and oxaliplatin as the first-line therapies for metastatic colorectal cancer: a meta-analysis

BACKGROUND

Irinotecan (IRI) and oxaliplatin (Ox) are standard therapeutic agents of the first-line treatments for metastatic colorectal cancer (mCRC). Previous meta-analyses of randomized controlled trials (RCTs) showed that treatment with Ox-based compared with IRI-based regimens was associated with better overall survival (OS). However, these reports did not include trials of molecular targeting agents and did not take methods for the administration of concomitant drugs, such as bolus or continuous infusion of 5-fluorouracil, into account. A systematic literature review was performed to compare the efficacy and toxicity profiles between IRI- and Ox-based regimens as the first-line treatments for mCRC.

METHODS

This meta-analysis used data from the Cochrane Central Register of Controlled Trials, PubMed, and SCOPUS. The primary endpoint was OS, and the secondary endpoints were progression-free survival (PFS), objective response rate (ORR), and adverse events (AEs).

RESULTS

Nineteen trials involving 4571 patients were included in the analysis. No statistically significant difference was observed between the two groups in terms of OS, PFS, and ORR. There was no significant heterogeneity. Regarding ≥ grade 3 AEs, IRI-based regimens were associated with a high incidence of leukopenia, febrile neutropenia, and diarrhea. Moreover, there was a high incidence of thrombocytopenia and peripheral sensory neuropathy in patients who received Ox-based regimens. In a subgroup analysis, IRI combined with bevacizumab was correlated with a better PFS (HR = 0.90, 95% CI = 0.82-0.98, P = 0.02), but not with OS (pooled HR = 0.91, 95% CI = 0.80-1.03, P = 0.15).

CONCLUSION

Although the safety profiles of IRI- and Ox-based regimens varied, their efficacy did not significantly differ. The combination of anti-VEGF antibody and IRI was associated with better PFS compared with anti-VEGF antibody and Ox. Both regimens could be used as the first-line treatments for mCRC with consideration of the patients' condition or toxicity profiles.

Clinical efficacy of irinotecan plus raltitrexed chemotherapy in refractory esophageal squamous cell cancer

Our retrospective study assessed the efficacy and safety of irinotecan plus raltitrexed in esophageal squamous cell cancer (ESCC) patients who were previously treated with multiple systemic therapies. Between January 2016 and December 2018, records of 38 ESCC patients who underwent irinotecan plus raltitrexed chemotherapy after at least one line of chemotherapy were reviewed. Efficacy assessment was performed every two cycles according to the RECIST version 1.1. A total of 95 cycles of chemotherapy were administered, and the median course was 3 (range 2-6). There was no treatment-related death. Nine patients had partial response, 21 had stable disease and eight had progressive disease. The overall objective response rate was 23.68% (9/38) and the disease control rate was78.94% (30/38). After a median follow-up of 18.5 months, the median progression-free survival and overall survival were 105 and 221 days, respectively. There were five patients (13.15%) with grade 3/4 leukopenia, three patients (7.89%) with grade 3/4 neutropenia and one patient (2.63%) with grade 3/4 diarrhea. The combination of irinotecan plus raltitrexed was effective for pretreated ESCC patients. Further studies are needed to determine the optimal dose of the two drugs.

Real-world Safety and Efficacy of Raltitrexed in Patients With Metastatic Colorectal Cancer

BACKGROUND

Use of fluoropyrimidine-based therapy in patients with metastatic colorectal cancer is associated with significant toxicities. This study aimed to assess the safety and efficacy of raltitrexed use in patients with metastatic colorectal cancer who developed significant toxicities after fluoropyrimidine-based treatment.

PATIENTS AND METHODS

We identified patients with metastatic colorectal cancer who were treated with raltitrexed-based systemic therapy after developing serious adverse events with fluoropyrimidine-based treatment in a large Canadian province from 2004 to 2018. Demographic, tumor, and treatment characteristics were retrieved from the electronic medical records. Progression-free and overall survival were assessed from the start of raltitrexed-based therapy.

RESULTS

A total of 86 patients were identified for the study. The median age was 66.5 years, and 58.1% of patients were men. The primary cancer site was right, left, and transverse colon in 38.4%, 27.9%, and 9.3%, respectively. The remaining 24.4% had rectal cancer. Among all patients, 43.0% had received more than 2 prior systemic therapies, and 37.6% had developed previous cardiotoxicity to fluoropyrimidine-based treatment. The median progression-free and overall survival were 8.5 and 10.2 months, respectively. On multivariable Cox regression model, patients with left-sided colon cancer (hazard ratio [HR], 0.33; 95% confidence interval [CI], 0.12-0.97; P = .044) and the Eastern Cooperative Oncology Group performance status of 0/1 (HR, 0.10; 95% CI, 0.01-0.82; P = .032) had a longer progression-free survival, whereas left-sidedness of colon cancer was the only factor that predicted overall survival (HR, 0.30; 95% CI, 0.10-0.88; P = .029). Raltitrexed was well-tolerated with common adverse events that included anemia in 41.7% of patients and chemotherapy-induced nausea and vomiting in 27.4%. Most toxicities were grade 1/2, but 16.7% of patients experienced grade 3. There were no cardiac events and treatment-related deaths.

CONCLUSIONS

Raltitrexed in patients with colorectal cancer who were previously treated with fluoropyrimidine-based systemic therapy is effective and well-tolerated.

Exposure-response analysis of Raltitrexed assessing liver toxicity

AIM

Raltitrexed (RTX) is a thymidylate synthase inhibitor with large pharmacokinetics (PK) variability that can be administered in case of 5-fluorouracil (5FU) intolerance or dihydropyrimidine dehydrogenase deficiency. While it is a more potent thymidylate synthase inhibitor than 5FU, RTX failed to replace this drug for colorectal cancer patients, mainly due to its toxicity at the recommended dose of 3 mg/m² every 3 weeks. However, every 2 weeks administration at 2 mg/m² demonstrated a favourable toxicity profile.

METHOD

We performed a randomized crossover comparative population PK study between every 2 weeks TOMOX (RTX 2 mg/m² ) and every 3 weeks TOMOX (RTX 3 mg/m² ).

RESULTS

A three-compartment model and a proportional error model best describe the data. Creatinine clearance and sex, but not body surface area (BSA), were covariates of RTX clearance leading to decrease of its interindividual variability of 28%. Weight and body surface area were covariates of central and peripheral volumes of distribution, respectively, leading to decreases of interindividual variability of 34.6% and 100%, respectively. In contrast to the dose, AUC was a good predictor of liver toxicity (P = 0.006, OR = 3.91, 95%CI = [1.48-10.34]). Using covariates to compute individual clearance and a threshold AUC (1.639, determined in this study), a covariates-based dose was calculated, leading to less variability in AUC than observed with the actual BSA-based or fixed doses.

CONCLUSION

These results advocate for the use of creatinine clearance and sex to determine the RTX dose instead of BSA.

Hepatic arterial chemotherapy with raltitrexed and oxaliplatin versus standard chemotherapy in unresectable liver metastases from colorectal cancer after conventional chemotherapy failure (HEARTO): a randomized phase-II study

BACKGROUND

Hepatic arterial infusion (HAI) of chemotherapy could be used in patients with liver-only metastatic colorectal cancer (mCRC) to fight against chemoresistance. We previously reported the efficacy of raltitrexed plus oxaliplatin (HAI) in a retrospective series. We performed a randomized two-stage phase-II study to evaluate the efficacy of HAI of the combination of raltitrexed and oxaliplatin in refractory mCRC with only liver metastases in comparison with standard of care.

PATIENTS AND METHODS

Eligible patients had unresectable mCRC and were refractory or intolerant to fluoropyrimidine, irinotecan, oxaliplatin, anti-VEGF therapy, and anti-EGFR therapy (for tumors with wild-type KRAS). Patients were randomized between HAI raltitrexed (3 mg/m2 over 1 h) followed by oxaliplatin (130 mg/m2 over 2 h) every 3 weeks and standard of care in a 2:1 ratio. A total of 57 patients (38 in the experimental arm and 19 in the standard of care arm) were to be included. The main objective was to demonstrate 6-month PFS of 45% by intention-to-treat analysis in the experimental arm, compared to theoretical PFS of 20%, with a unilateral alpha risk of 5% and beta risk of 10%.

RESULTS

After inclusion of 27 patients, the trial was terminated due to insufficient accrual. In the experimental arm, 11 and 4 patients experienced grade 3 and 4 toxicities, respectively. The most frequent grade 3-4 toxicities were neutropenia, liver toxicity, and abdominal pain. Median progression-free survival was 6.7 months (95% Confidence Interval; 3.9-7.2) in the HAI group and 2.2 months (95% CI 1.2-4.3) with standard of care [HR 0.32 (95% CI 0.14-0.76), p = 0.01]. Median overall survival did not differ between the two groups, at 11.2 months (95% CI 4.8-17.6) for the HAI group and 11.9 months (95% CI 2.8-14.3) for standard of care [HR 0.86 (95% CI 0.36-2.04), p = 0.73].

CONCLUSION

Although stopped prematurely, this randomized trial provides evidence for the benefit and safety of HAI of a combination of raltitrexed and oxaliplatin in liver-only mCRC with chemoresistant disease.

Transarterial chemoembolization with raltitrexed-based or floxuridine-based chemotherapy for unresectable colorectal cancer liver metastasis

PURPOSE

To evaluate and compare the efficiency and safety of raltitrexed- or floxuridine (FUDR)-based transarterial chemoembolization (TACE) in patients with unresectable colorectal cancer liver metastasis (CRCLM).

METHODS

We conducted a retrospective analysis of 81 patients with unresectable CRCLM who failed systemic chemotherapy and were treated with TACE in our department from Oct 2014 to Oct 2017. Of these, 61 patients received TACE using raltitrexed, oxaliplatin, and pirarubicin (raltitrexed group), and 20 received TACE using FUDR, oxaliplatin, and pirarubicin (FUDR group). The objective response rate (ORR), disease control rate (DCR), overall survival (OS, from the first TACE), progression-free survival (PFS, from the first TACE), and adverse reactions were evaluated and compared between the two groups, and prognostic factors for OS were analyzed.

RESULTS

The ORRs of the raltitrexed group and FUDR group were 67.2 and 45.0%, respectively (P = 0.076), and the DCRs were 86.9 and 80.0%, respectively (P = 0.452). The median OS (from first TACE) was 14.0 months in the raltitrexed group and 13.0 months in the FUDR group (P = 0.556). The median PFS (from first TACE) was 2.1 months in the raltitrexed group and 2.4 months in the FUDR group (P = 0.878). Univariate and multivariate analyses showed that the primary tumor site, Child-Pugh class, and combination with local ablation (RFA or CRA) were independent significant factors affecting survival. There were no significant differences in adverse reactions between the two groups (P > 0.05), and no treatment-related death occurred in either group.

CONCLUSION

TACE treatment based on raltitrexed or FUDR is an efficient and safe alternative choice for treating unresectable CRCLM.

Predictive factors for the development of irinotecan-related cholinergic syndrome using ordered logistic regression analysis

Cholinergic syndrome is an acute adverse reaction associated with irinotecan. Development of cholinergic syndrome can be ameliorated or prevented by administering various anticholinergics, including atropine sulfate or scopolamine butylbromide. Although many of the side effects are transient and non-life-threatening, their onset is painful and can lower a patient's quality of life (QoL). This retrospective study was performed to identify predictive factors of the development of irinotecan-related cholinergic syndrome in order to develop future strategies for improving the QoL of patients undergoing chemotherapy. We enrolled 150 cancer patients who underwent chemotherapy, which included irinotecan, in our outpatient chemotherapy center between October 2014 and January 2017. For regression analysis, variables related to the development of irinotecan-related cholinergic syndrome were extracted from the patient's clinical records. The degree of cholinergic syndrome was classified as follows: grade 0 = not developed; grade 1 = developed but did not require anticholinergic drugs; and grade 2 = developed and required anticholinergic drugs or stopping the chemotherapy due to cholinergic syndrome. Multivariate ordered logistic regression analysis was performed to identify predictive factors for the development of irinotecan-related cholinergic syndrome. Threshold measurements were determined using a receiver operating characteristic analysis (ROC) curve. Significant factors identified for the development of cholinergic syndrome included female sex [odds ratio (OR) 2.183, 95% confidence interval (CI) 1.010-4.717; P = 0.0471] and irinotecan dose (OR 1.014, 95% Cl 1.007-1.021; P = 0.0001). ROC curve analysis of the group likely to develop cholinergic syndrome indicated that the threshold for the irinotecan dose was 175 mg or above (area under the curve = 0.69). In conclusion, female sex and irinotecan dose were identified as significant predictors of the development of cholinergic syndrome.

Hepatic artery infusion with raltitrexed or 5-fluorouracil for colorectal cancer liver metastasis

AIM

To evaluate the efficiency and safety of hepatic artery infusion chemotherapy (HAIC) using raltitrexed or 5-fluorouracil for colorectal cancer (CRC) liver metastasis (CRCLM).

METHODS

A retrospective analysis of patients with unresectable CRCLM who failed systemic chemotherapy and were subsequently treated with HAIC at our institute from May 2013 to April 2015 was performed. A total of 24 patients were treated with 5-fluorouracil, and 18 patients were treated with raltitrexed.

RESULTS

The median survival time (MST) from diagnosis of CRC was 40.8 mo in the oxaliplatin plus raltitrexed (TOMOX) arm and 33.5 mo in the oxaliplatin plus 5-fluorouracil (FOLFOX) arm (P = 0.802). MST from first HAIC was 20.6 mo in the TOMOX arm and 15.4 mo in the FOLFOX arm (P = 0.734). Median progression-free survival (PFS) from first HAIC was 4.9 mo and 6.6 mo, respectively, in the TOMOX arm and FOLFOX arm (P = 0.215). Leukopenia (P = 0.026) was more common in the FOLFOX arm, and hepatic disorder (P = 0.039) was more common in the TOMOX arm. There were no treatment-related deaths in the TOMOX arm and one treatment-related death in the FOLFOX arm. Analysis of prognostic factors indicated that response to HAIC was a significant factor related to survival.

CONCLUSION

No significant difference in survival was observed between the TOMOX and FOLFOX arms. HAIC treatment with either TOMOX or FOLFOX was demonstrated as an efficient and safe alternative choice.

A systematic review of raltitrexed-based first-line chemotherapy in advanced colorectal cancer

Raltitrexed is a thymidylate synthase inhibitor belonging to the antimetabolite class of cytotoxic drugs. It is also effective in colorectal cancer (CRC) both as a single agent and in combination with other drugs, in particular in those patients with cardiologic risk factors or previous cardiotoxicity. The efficacy of first-line raltitrexed-based chemotherapy containing oxaliplatin (TOMOX) and irinotecan (TOMIRI) was investigated in this systematic review. Studies that enrolled advanced CRC patients for first-line therapy with TOMOX/TOMIRI combinations were identified using electronic databases (Pubmed, SCOPUS, Web of Science, EMBASE, and the Cochrane Library). A systematic analysis was carried out using Comprehensive Meta Analysis (version 2.2.064) software to calculate the pooled response rate and 95% confidence limits. The median pooled overall survival and progression-free survival were also calculated. Results for TOMOX and TOMIRI studies were compared using the two-sided Student's t-test. We tested for significant heterogeneity using Cochran's χ-test and I index. Twelve studies published between 2001 and 2012 were eligible for this analysis and a total of 735 patients were enrolled in these studies. The overall response rate was 40% (95% confidence interval 34-46%): 43.9% for TOMOX and 34.1% for TOMIRI arms. The weighted median overall survival and progression-free survival times were 14.6 and 6.7 months, respectively. Neutropenia and liver toxicity were more frequent with TOMOX, whereas neutropenia and diarrhea were more frequent with TOMIRI. However, compared with historical FOLFOX and FOLFIRI trials, raltitrexed-based doublets are associated with less neutropenia and gastrointestinal toxicity and uncommon cardiotoxicity. TOMOX and TOMIRI doublets are active as first-line chemotherapy for advanced CRC and seem useful in particular when the use of 5-fluorouracil is contraindicated for cardiac comorbidity.

Final results of Australasian Gastrointestinal Trials Group ARCTIC study: an audit of raltitrexed for patients with cardiac toxicity induced by fluoropyrimidines

BACKGROUND

Cardiac toxicity an uncommon but serious side-effect of some fluoropyrimides. Cardiac toxicity from raltitrexed is rarely reported. With this background, we initiated this study to investigate the incidence of cardiac events in patients who had switched to raltitrexed following cardiac toxicity from fluoropyrimidines (5-fluorouracil or capecitabine).

PATIENTS AND METHODS

Pharmacy records were used to identify patients receiving raltitrexed from January 2004 till March 2012. Medical records were then reviewed to confirm the use of raltitrexed after cardiac toxicity from 5-fluorouracil or capecitabine. The primary end point was the rate of further cardiac events after commencing raltitrexed.

RESULTS

Forty-two patients were identified and the majority had colorectal cancer. Prior regimens included 5-fluorouracil ± leucovorin, capecitabine alone, FOLFOX, FOLFIRI, epirubicin/cisplatin/5-fluorouracil, and capecitabine/oxaliplatin. Seven patients (17%) had bolus 5-fluorouracil regimens, 26 patients (62%) had infusion 5-fluorouracil regimens, and 9 patients (21%) had capecitabine alone or in combination. Angina was the most common cardiac toxicity from 5-fluorouracil or capecitabine and usually occurred in the first or the second cycle. Four patients after their first cardiac event continued with the same 5-fluorouracil or capecitabine regimen with the addition of nitrates and calcium antagonists but still had further cardiac events. After changing to raltitrexed, either as a single agent or a continuing combination regimen, no patients experienced further cardiac toxicity.

CONCLUSION

Raltitrexed is associated with no significant cardiac toxicity in patients who have experienced prior cardiac toxicity from 5-fluorouracil or capecitabine. Raltitrexed, alone or in combination with oxaliplatin or irinotecan, provides a safe option in terms of cardiac toxicity for such patients.

Targeting thymidylate synthase in colorectal cancer: critical re-evaluation and emerging therapeutic role of raltitrexed

INTRODUCTION

5-fluorouracil continues to be the cornerstone of treatment for colorectal cancer. Although fluoropyrimidines are generally considered as well-tolerated drugs, severe toxicities can be a major clinical problem, and the recommended prolonged infusion of 5-fluorouracil provokes discomfort in patients. Raltitrexed (Tomudex), a quinazoline analogue of folinic acid, is a selective and direct thymidylate synthase (TS) inhibitor with a convenient 3-weekly schedule of administration.

AREAS COVERED

In this review, through critical insight into the mechanism of action and main clinical experiences, the authors suggest the necessity to reconsider raltitrexed as a valuable anticancer drug and as a suitable option for colorectal cancer. The authors highlight its emerging therapeutic role in clinical practice for patients with fluoropyrimidine-induced cardiotoxicity or a significant history of cardiac disease.

EXPERT OPINION

This review discusses if TS could still be a relevant target for colorectal cancer in the era of molecular therapy and if raltitrexed should still be considered a drug with a life-threatening toxicity. Furthermore, this review discusses the principal combination clinical experiences of raltitrexed and its emerging therapeutic role in clinical practice as a suitable option for colorectal cancer patients with fluoropyrimidine-induced cardiotoxicity or a significant history of cardiac disease.

Alternative treatment options in colorectal cancer patients with 5-fluorouracil- or capecitabine-induced cardiotoxicity

Most chemotherapy regimens in colorectal cancer treatment are 5-fluorouracil (5-FU)/leucovorin or capecitabine-based. Cardiotoxicity is a less common but potentially lethal complication of 5-FU or capecitabine treatment, and some physicians might be unfamiliar with treatment alternatives. Rechallenging should be avoided because it carries a high risk of recurrence of the cardiac symptoms and prophylactic treatment is not always protective. Possible alternative treatment options to be considered are to replace the oral capecitabine or intravenous 5-FU by a 5-FU bolus regimen, by uracil-tegafur or tegafur/gimeracil/oteracil, both oral fluoropyrimidines combining a 5-FU prodrug with a dihydropyrimidine dehydrogenase (DPD) inhibitor, or by raltitrexed, a thymidilate synthase inhibitor whose metabolism is independent of DPD. Patients with advanced colorectal cancer and fluoropyrimidine-induced cardiotoxicity can be treated with other non-fluoropyrimidine related chemotherapy, either as a single agent, combined, or in combination with biological agents. In this report we discuss the different alternative treatment options.

A randomized phase II study to compare oxaliplatin plus 5-fluorouracil and leucovorin (FOLFOX4) versus oxaliplatin plus raltitrexed (TOMOX) as first-line chemotherapy for advanced colorectal cancer

INTRODUCTION

The aim of this study was to compare TOMOX versus FOLFOX4 as first-line treatment of advanced colorectal cancer (CRC).

MATERIALS AND METHODS

191 chemotherapy-naïve patients were randomized to receive TOMOX or FOLFOX4. Patients were evaluated every 3 months and chemotherapy was continued until disease progression or unacceptable toxicity. Overall response rate was the primary endpoint.

RESULTS

183 patients were included in the intent-to-treat analysis (92 TOMOX and 91 FOLFOX4). Overall response rate was 45.6 and 36.3 % (p = 0.003) for TOMOX and FOLFOX4, respectively. No statistically significant differences were observed in overall survival (15.6 and 17.2 months; p = 0.475); progression-free survival (7.7 and 8.7 months; p = 0.292), and response duration (6.4 and 7.6 months; p = 0.372) for TOMOX and FOLFOX4, respectively. Grades 3 and 4 neutropenia (p < 0.0001) and leukopenia (p = 0.028) were more common with the FOLFOX4 regimen, while hepatic disorders and asthenia were higher in TOMOX group (p = ns). There were two treatment-related deaths in the FOLFOX4 arm and one in the TOMOX arm. Quality of life analysis based on the SF-36 revealed differences between the two regimens for physical and mental composite scores after 6 weeks, and for body pain and emotional role functioning after 6 and 12 weeks; all of these favored the FOLFOX4 arm (p ≤ 0.05).

CONCLUSIONS

TOMOX and FOLFOX4 seem to have similar efficacy and are well tolerated in the first-line treatment for advanced CRC with different profiles of toxicity. The convenient TOMOX regimen may offer an alternative to fluoropyrimidine-based regimens.

Raltitrexed and oxaliplatin hepatic arterial infusion for advanced colorectal cancer: a retrospective study

The aim of this study was to evaluate the efficacy and safety of combined hepatic arterial infusion (HAI), which is a combination of raltitrexed and oxaliplatin, in refractory colorectal carcinoma with only liver metastases. Seventeen consecutive patients with unresectable metastatic colorectal cancer, after the failure of two lines of systemic chemotherapy, were treated with HAI raltitrexed (3 mg/m over 1 h) followed by oxaliplatin (130 mg/m over 2 h) every 3 weeks between January 2006 and January 2009. All patients presented with the metastatic disease limited to the liver and had failed at least two lines of chemotherapy, which contained oxaliplatin, irinotecan and a fluoropyrimidine. The median number of cycles was six (range 1-15). We observed three complete responses and eight partial responses among assessable patients (overall response rate in intention to treat, 65%; 95% confidence interval, 44.3-87.7%). The median time to progression was 10.5 months and the median survival time was 27.5 months. Toxicity included grade 3-4 neutropenia (in 17%), grade 3-4 thrombopenia (in 17%), and grade 2 abdominal pain (in 47%). In conclusion, the combination regimen of HAI raltitrexed and oxaliplatin is feasible and promising in patients who presented isolated hepatic metastases of colorectal cancer after failure of irinotecan and oxaliplatin treatment. Further evaluation of this combination is required.

Survival and disease-progression benefits with treatment regimens for advanced colorectal cancer: a meta-analysis

BACKGROUND

Many randomised trials have compared different systemic treatment regimens in patients with advanced colorectal cancer. While survival advances have apparently been achieved, the magnitude of these incremental benefits across diverse regimens is less clear. The aim of our study was to estimate the magnitude of survival and disease progression benefits with the use of different regimens in patients with advanced colorectal cancer.

METHODS

We systematically reviewed randomised trials comparing systemic treatment regimens in advanced colorectal cancer. Treatment was categorised by use of or no use of fluorouracil-based regimens, irinotecan, oxaliplatin, bevacizumab, and cetuximab. We used multiple-treatment meta-analysis methodology to combine information from direct comparisons (ie, treatments compared within a randomised trial) and indirect comparisons (ie, treatments compared between trials by combining results on how effective they are against a common comparator treatment) of different chemotherapy regimens. The primary endpoint was death and the secondary endpoint was disease progression. Monte Carlo simulations were used to establish which regimen offered the most benefit for these endpoints. We did analyses of all trials and analysed separately trials that studied first-line treatments and non-first-line treatments.

FINDINGS

242 trials published in 1967-2007 (N=56 677 patients) involved 137 different chemotherapy regimens. 37 of these trials were eligible for the multiple-treatment meta-analysis, according to our categorisation, including 47 comparisons of data on death (N=13 875 patients) and 48 comparisons of data on disease progression (N=15 158 patients). Compared with fluorouracil plus leucovorin alone, the risk of death was most decreased with the addition of irinotecan plus bevacizumab (hazard ratio [HR] 0.60, 95% credibility intervals (CrI) 0.44-0.84) and considerable benefits were also noted with addition of irinotecan plus oxaliplatin (HR 0.72 [95% CrI 0.54-0.97]); oxaliplatin plus bevacizumab (HR 0.72 [0.57-0.90]); bevacizumab alone (HR 0.78 [0.60-1.03]); and oxaliplatin alone (HR 0.87 [0.78-0.98]). The disease progression benefits were even more prominent for the addition of irinotecan plus bevacizumab (HR 0.41 [0.28-0.60]); irinotecan plus oxaliplatin (0.53 [0.38-0.73]); oxaliplatin plus bevacizumab (0.46 [0.34-0.61]); bevacizumab alone (0.56 [0.41-0.76]); oxaliplatin alone (0.64 [0.56-0.73]); irinotecan plus cetuximab (HR 0.62 [0.42-0.92]); and irinotecan alone (HR 0.73 [0.65-0.82]). Findings were similar for first-line and non-first-line treatment analyses although data were sparse for non-first-line treatment analyses. Compared with a patient with an anticipated 1-year survival who is treated with fluorouracil and leucovorin, the absolute survival benefit is estimated at 8 months' prolongation with addition of irinotecan plus bevacizumab, 4.7 months' prolongation with addition of oxaliplatin plus bevacizumab or irinotecan plus oxaliplatin, and 1-1.8 months' prolongation with addition of irinotecan alone or oxaliplatin alone.

INTERPRETATION

Distinct incremental benefits are noted for diverse chemotherapy regimens in patients with advanced colorectal cancer, with more prominent effects on disease progression than on death. More data are needed at least for the newest drugs to estimate more accurately the magnitude of the benefit derived from their use.

Synergistic antitumour effect of raltitrexed and 5-fluorouracil plus folinic acid combination in human cancer cells

5-Fluorouracil, usually in combination with folinic acid, is widely used in the treatment of both colorectal and head and neck squamous cell cancer patients. Since 5-fluorouracil plus folinic acid and the antifolate thymidylate synthase inhibitor; raltitrexed have distinct mechanisms of action and toxicity profiles, we have evaluated the potential synergistic antitumor interaction between these two agents combined with a sequential schedule of administration in KB (wt-p53) and Cal27 (mut-p53) head and neck squamous cell carcinomas, and LoVo (wt-p53) and HT29 (mut-p53) colorectal cell lines. The combination between a 24-h exposure to raltitrexed followed by a 4-h exposure to 5-fluorouracil plus folinic acid was globally synergistic, as assessed by the median effect principle and combination index. A specific contribution of folinic acid to the cytotoxic effect of the raltitrexed/5-fluorouracil combination was clearly demonstrated by the evaluation of the potentiation factor. In all cell lines, a 1.5- up to 17-fold reduction in the IC50 of both raltitrexed and 5-fluorouracil plus folinic acid was observed in the combination setting compared with the concentrations of the each drug used alone. Moreover, we demonstrated that raltitrexed/5-fluorouracil plus folinic acid induced a distinct S-phase block of the cell cycle, as well as a potentiation of the apoptotic cell death, compared with 5-fluorouracil plus folinic acid or raltitrexed/5-fluorouracil combination. This preclinical work represents, at least to our knowledge, the first demonstration of a synergistic interaction between raltitrexed and 5-fluorouracil modulated by folinic acid, and could represent a rationale for further clinical investigation of raltitrexed/5-fluorouracil plus folinic acid combination.

Pemetrexed and Oxaliplatin for Metastatic Colorectal Cancer: Results of a Phase I Mayo Cancer Center Research Consortium Trial, MC0248

PURPOSE

Pemetrexed, an antifolate involved in purine and pyrimidine formation, is a potential alternative to fluoropyrimidines in the treatment of colorectal cancer. A phase I trial was performed to establish the maximum tolerated dose (MTD) of pemetrexed and oxaliplatin when B(12) and folate supplementation is used.

PATIENTS AND METHODS

Patients with metastatic colorectal cancer received folate (> 350 microg) daily and vitamin B(12) (1000 microg) every 9 weeks starting 7 days before chemotherapy. Pemetrexed over 10 minutes and oxaliplatin over 2 hours were given every 3 weeks in escalating dose cohorts.

RESULTS

Twenty-two patients were entered on 6 dose levels. The MTD was established at the highest dose level, pemetrexed 900 mg/m(2) and oxaliplatin 130 mg/m(2). Toxicities related to treatment at the MTD included grade 3 neutropenia and thrombocytopenia. For all dose levels combined, grade 3/4 toxicities included hematologic, neurologic, and gastrointestinal. Nine of 21 evaluable patients responded overall (response rate, 43%). The time to tumor progression was 11.9 months.

CONCLUSION

The MTD was determined to be pemetrexed 900 mg/m(2) and oxaliplatin 130 mg/m(2) every 21 days when folate and B (12) supplementation are used. Because of the observed tolerability and activity of this regimen, further evaluation is warranted.

Raltitrexed plus levofolinic acid and bolus/continuous infusion 5-fluorouracil on a biweekly schedule for elderly patients with advanced colorectal carcinomas

BACKGROUND

The aim of the study was to evaluate the safety and efficacy of the raltitrexed/5-fluorouracil/levofolinic acid combination regimen as first-line chemotherapy for elderly patients with advanced/metastatic colorectal cancer.

PATIENTS AND METHODS

Previously untreated patients with metastatic colorectal cancer received raltitrexed 2 mg/m(2) i.v. plus levofolinic acid and 5-fluorouracil according to the De Gramont' schedule given every 2 weeks as first-line chemotherapy. Patients were re-evaluated after six cycles and chemotherapy was continued up to tolerance or disease progression.

RESULTS

Seventy patients aged >/=65 years were accrued from 11 centers between September 2001 and July 2002. According to the intention-to-treat analysis, the overall response rate was 35% (95% CI 29.5% to 40.5%) including one complete response (1%) and 24 partial responses (34%). Twenty patients (31%) showed a stabilization of disease for a tumor growth control rate of 64% (95% CI 57% to 71%). The median overall survival was 12.5 months and the median time to disease progression was 6.5 months. No toxic deaths or allergic reaction were recorded. Grade 4 toxicities were non-existent. The main hematological toxicity was grade 3 neutropenia, which occurred in 9% of patients, and grade 3 anemia in only one case, while no case of graded 3 thrombocytopenia was observed. Grade 3 non-hematological toxicities were asthenia (11%), transient increase of transaminases (10%) and diarrhea (4%).

CONCLUSIONS

The results of this study suggest that the raltitrexed/5-fluorouracil/levolofinic acid combination is an effective and well tolerated regimen for the treatment of elderly patients with advanced colorectal cancer. Its ease of administration and patient's tolerance warrant further investigation over 5-fluorouracil/folinic acid regimens.