Phase I study of TAS-102 treatment in Japanese patients with advanced solid tumours

Predictive significance of FGFR4 p.G388R polymorphism in metastatic colorectal cancer patients receiving trifluridine/tipiracil (TAS-102) treatment

BACKGROUND

TAS-102 (Lonsurf®) is an oral fluoropyrimidine consisting of a combination of trifluridine (a thymidine analog) and tipiracil (a thymidine phosphorylation inhibitor). The drug is effective in metastatic colorectal cancer (mCRC) patients refractory to fluorouracil, irinotecan and oxaliplatin. This study is a real-world analysis, investigating the interplay of genotype/phenotype in relation to TAS-102 sensitivity.

METHODS

Forty-seven consecutive mCRC patients were treated with TAS-102 at the National Cancer Institute of Naples from March 2019 to March 2021, at a dosage of 35 mg/m2, twice a day, in cycles of 28 days (from day 1 to 5 and from day 8 to 12). Clinical-pathological parameters were described. Activity was evaluated with RECIST criteria (v1.1) and toxicity with NCI-CTC (v5.0). Survival was depicted through the Kaplan-Meyer curves. Genetic features of patients were evaluated with Next Generation Sequencing (NGS) through the Illumina NovaSeq 6000 platform and TruSigt™Oncology 500 kit.

RESULTS

Median age of patients was 65 years (range: 46-77). Forty-one patients had 2 or more metastatic sites and 38 patients underwent to more than 2 previous lines of therapies. ECOG (Eastern Cooperative Oncology Group) Performance Status (PS) was 2 in 19 patients. The median number of TAS-102 cycles was 4 (range: 2-12). The most frequent toxic event was neutropenia (G3/G4 in 16 patients). There were no severe (> 3) non-haematological toxicities or treatment-related deaths. Twenty-six patients experienced progressive disease (PD), 21 stable disease (SD). Three patients with long-lasting disease control (DC: complete, partial responses or stable disease) shared an FGFR4 (p.Gly388Arg) mutation. Patients experiencing DC had more frequently a low tumour growth rate (P = 0.0306) and an FGFR4 p.G388R variant (P < 0.0001). The FGFR4 Arg388 genotype was associated with better survival (median: 6.4 months) compared to the Gly388 genotype (median: 4 months); the HR was 0.25 (95% CI 0.12- 0.51; P = 0.0001 at Log-Rank test).

CONCLUSIONS

This phenotype/genotype investigation suggests that the FGFR4 p.G388R variant may serve as a new marker for identifying patients who are responsive to TAS-102. A mechanistic hypothesis is proposed to interpret these findings.

Combination therapy with WEE1 inhibition and trifluridine/tipiracil against esophageal squamous cell carcinoma

Despite advanced therapeutics, esophageal squamous cell carcinoma (ESCC) remains one of the deadliest cancers. Here, we propose a novel therapeutic strategy based on synthetic lethality combining trifluridine/tipiracil and MK1775 (WEE1 inhibitor) as a treatment for ESCC. This study demonstrates that trifluridine induces single-strand DNA damage in ESCC cells, as evidenced by phosphorylated replication protein 32. The DNA damage response includes cyclin-dependent kinase 1 (CDK1) (Tyr15) phosphorylation as CDK1 inhibition and a decrease of the proportion of phospho-histone H3 (p-hH3)-positive cells, indicating cell cycle arrest at the G2 phase before mitosis entry. The WEE1 inhibitor remarkedly suppressed CDK1 phosphorylation (Try15) and reactivated CDK1, and also increased the proportion of p-hH3-positive cells, which indicates an increase of the number of cells into mitosis. Trifluridine combined with a WEE1 inhibitor increased trifluridine-mediated DNA damage, namely DNA double-strand breaks, as shown by increased γ-H2AX expression. Moreover, the combination treatment with trifluridine/tipiracil and a WEE1 inhibitor significantly suppressed tumor growth of ESCC-derived xenograft models. Hence, our novel combination treatment with trifluridine/tipiracil and a WEE1 inhibitor is considered a candidate treatment strategy for ESCC.

Prognostic factors in refractory metastatic colorectal cancer patients treated with Trifluridine/Tipiracil

PURPOSE

The systemic treatment options for metastatic colorectal cancer (mCRC) are unsatisfactory, and the disease recurs despite the use of numerous medications and their combinations. Trifluridine/Tipiracil is a relatively new drug used in refractory mCRC. Little is known about its real-world effectiveness and prognostic and predictive factors. Therefore, this study aimed to develop a prognostic model for refractory mCRC treated with Trifluridine/Tipiracil.

METHODS

We retrospectively evaluated the data from 163 patients who had received Trifluridine/Tipiracil as a third or fourth line of treatment for refractory mCRC.

RESULTS

After starting Trifluridine/Tipiracil, 21.5% of patients survived one year, and the median overall survival after Trifluridine/Tipiracil initiation was 251 days (SD: 17.855; 95%CI: 216-286). Median progression-free survival after Trifluridine/Tipiracil initiation was 56 days (SD: 4.826; 95%CI 47-65). Moreover, the median overall survival from diagnosis was 1333 days (SD: 82.84; 95%CI: 1170-1495). In forward stepwise multivariate Cox regression analysis, initial radical treatment (HR = 0.552, 95% CI 0.372-0.819, p < 0.003), the number of cycles of first-line chemotherapy (HR = 0.978, 95% CI 0.961-0.995, p < 0.011), the number of cycles of second-line chemotherapy (HR = 0.955, 95% CI 0.931-0.98, p < 0.011), BRAF mutation (HR = 3.016, 95% CI = 1.207-7.537, p = 0.018), and hypertension (HR = 0.64, 95% CI = 0.44-0.931, p = 0.02) were all associated with survival after Trifluridine/Tipiracil initiation. Our model and model-based nomogram displayed an AUC of 0.623 for one-year survival estimation in the testing cohort. The C-index for the prediction nomogram was 0.632.

CONCLUSION

We have developed a prognostic model for refractory mCRC treated with Trifluridine/Tipiracil based on five variables. Moreover, we reported a nomogram which could be used by oncologists in clinic visits on a daily basis.

Trifluridine/tipiracil in the treatment of gastric cancer

Trifluridine/tipiracil is a compound drug, approved in 2015 by the Food and Drug Administration, and in 2016 by the European Medicines Agency, for the treatment of chemorefractory metastatic colorectal cancers, after the phase 3 RECOURSE trial demonstrated significant benefit. Another phase 3 trial (TAGS) showed significant improvement of overall survival and progression-free survival in refractory gastric cancer and gastroesophageal junction cancer, leading to further approval from the FDA on February 2019, followed by Japan in August 2019 and the European Union in September 2019. As promising results have already been observed in the chemorefractory gastric and gastroesophageal-junction cancers, ongoing trials are assessing the use of trifluridine/tipiracil with other standard of care agents, aiming to further improve the survival rate of these patients.

A phase I, open-label study evaluating the safety and pharmacokinetics of trifluridine/tipiracil in patients with advanced solid tumors and varying degrees of renal impairment

PURPOSE

Trifluridine/tipiracil (FTD/TPI) is approved for advanced colorectal and gastric/gastroesophageal cancer; however, data in patients with renal impairment (RI) are limited. This phase I study evaluated FTD/TPI in patients with advanced solid tumors and varying degrees of RI to develop dosing guidance.

METHODS

Patients were enrolled into normal renal function (CrCl ≥ 90 mL/min), mild RI (CrCl 60-89 mL/min), or moderate RI (CrCl 30-59 mL/min) cohorts and administered the recommended FTD/TPI dose (35 mg/m² twice daily, days 1-5 and 8-12; 28-day cycle). Based on interim pharmacokinetics/safety data, patients with severe RI (CrCl 15-29 mL/min) were enrolled and received FTD/TPI 20 mg/m² twice daily.

RESULTS

Forty-three patients (normal renal function [n = 12]; mild RI [n = 12]; moderate RI [n = 11]; severe RI [n = 8]) were enrolled and treated. At steady state, compared to values in patients with normal renal function, FTD area under the curve (AUC) was not significantly different in patients with RI, but TPI AUC was significantly higher and increased with RI severity. FTD/TPI safety profile was consistent with prior experience, but grade ≥ 3 adverse events (AEs) were more frequent in the RI cohorts (83.3% [mild], 90.9% [moderate], 75.0% [severe], and normal [50.0%]). Hematologic AEs (anemia and neutropenia) were more frequent with RI. Overall, seven patients discontinued because of unrelated, nonhematologic AEs.

CONCLUSION

FTD/TPI is safe and tolerable at the recommended 35 mg/m² dose in patients with mild/moderate RI and at the reduced 20 mg/m² dose in patients with severe RI.

TRIAL REGISTRATION

NCT02301117, registration date: November 21, 2014.

Phase II study of trifluridine/tipiracil (TAS-102) therapy in elderly patients with colorectal cancer (T-CORE1401): geriatric assessment tools and plasma drug concentrations as possible predictive biomarkers

PURPOSE

The current study aimed to determine the efficacy of trifluridine/tipiracil for elderly patients with advanced colorectal cancer.

METHODS

This single-arm, open-label, multicenter, phase II study included elderly patients aged 65 years or more who had fluoropyrimidine-refractory advanced colorectal cancer and received trifluridine/tipiracil (70 mg/m², days 1-5 and 8-12, every 4 weeks). The primary endpoint was progression-free survival (PFS), while secondary endpoints included overall survival (OS), overall response rate (ORR), toxicities, association between efficacy and geriatric assessment scores, and association between toxicity and plasma drug concentrations.

RESULTS

A total of 30 patients with a mean age of 73 years were enrolled. Median PFS was 2.3 months (95% confidence interval, 1.9-4.3 months), while median OS was 5.7 months (95% confidence interval, 3.7-8.9 months). Patients had an ORR of 0%, with 57% having stable disease. Grade 4 neutropenia was observed in 13% of the patients. Patients with a higher G8 score (15 or more) showed longer PFS than those with a lower G8 score (median 4.6 vs. 2.0 months; p = 0.047). Moreover, patients with grade 3 or 4 neutropenia showed higher maximum trifluridine concentrations than those with grade 1 or 2 neutropenia (mean 2945 vs. 2107 ng/mL; p = 0.036).

DISCUSSION

The current phase II trial demonstrated that trifluridine/tipiracil was an effective and well-tolerated option for elderly patients with advanced colorectal cancer. Moreover, geriatric assessment tools and/or plasma drug concentration monitoring might be helpful in predicting the efficacy and toxicities in elderly patients receiving this drug.

TRIAL REGISTRATION NUMBER

UMIN000017589, 15/May/2015 (The University Hospital Medical Information Network).

TAS-102: A resurrected novel Fluoropyrimidine with expanding role in the treatment of gastrointestinal malignancies

TAS-102 is an orally administered fixed-dose formulation consisting of trifluorothymidine (TFT), a fluoropyrimidine antimetabolite, and tipiracil (TPI), an inhibitor of thymidine phosphorylase (TP) that prevents rapid degradation of TFT and ensures its bioavailability. The novelty of TAS-102 lies in its antitumor activity against 5-fluorouracil (5-FU) resistant tumors, demonstrated both in the in vitro models and xenografts. The cytotoxic activity of TFT relies primarily on extensive incorporation of the TFT metabolite into the cellular DNA inducing DNA dysfunction and cell death. In contrast, 5-fluorouracil (5-FU) interferes with DNA biosynthesis by inhibiting thymidylate synthase(TS), which partly explains the absence of cross-resistance between TAS-102 and 5-FU. TAS-102 is currently approved in the third-line setting for patients with metastatic colorectal and gastric cancer based on phase III randomized clinical trial data confirming an overall survival benefit with TAS-102. The preliminary data from recently reported studies suggest a potential expanding role of TAS-102 in a variety of gastrointestinal (GI) cancers. The current article presents an overview of the pharmacology, clinical development of TAS-102, and its emerging role in the treatment of GI cancers. In addition, we discussed the rationale underlying the ongoing clinical trials investigating various combinations of TAS-102 with other anticancer agents, including targeted therapies, in a wide range of GI tumors.

Appropriateness of trifluridine/tipiracil in the clinical practice of third-line therapy in metastatic colorectal cancer

Aim: To help to remove misperception of an appropriate position of trifluridine/tipiracil (FTD/TPI) in the treatment of metastatic colorectal cancer. Materials & methods: The RAND Corporation/UCLA Appropriateness Method was used by a panel of Italian experts to develop recommendations concerning daily practice with FTD/TPI. Forty-three clinical scenarios were discussed in two rounds and the resulting statements were rated as appropriate, uncertain or inappropriate, according to the median score. Results: Several topics were dealt with, covering the profile of eligible patients, therapeutic options beyond the second line, the practice of treatment with FTD/TPI, evaluation and efficacy and toxicity, as well as costs and compliance. Conclusion: FTD/TPI is an important therapeutic resource in refractory metastatic colorectal cancer that combines manageability and safety.

The effect of trifluridine/tipiracil for patients with heavily pretreated metastatic gastric cancer: A protocol for systematic review and meta-analysis

BACKGROUND

Gastric cancer is a global health problem with high incidence rate and mortality rate. Due to the limitations of traditional chemotherapy drugs, such as patient intolerance, low efficacies and serious adverse effects, trifluridine/tipiracil has been considered to be a promising treatment for patients with heavily pretreated metastatic gastric cancer. However, the relevant systematic review has not been occurring. The presentation of this protocol is to scientifically evaluate the efficacy and safety of trifluridine/tipiracil in patients with highly pretreated metastatic gastric cancer.

METHODS

The protocol followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols. We will systematically search MEDLINE, PubMed, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure Database (CNKI), VIP Chinese Science and Technology Periodical Database (VIP), Wan Fang Database up to November 1, 2020 to identify published articles. Using the Cochrane risk assessment tool to assess the methodological quality of the RCTs, and all included studies will be analyzed according to the criteria in the Cochrane Handbook. Review Manager 5.3 software will be used for literature quality evaluation and data analysis.

RESULTS

Objective to evaluate the efficacy and safety of trifluridine/tipiracil in patients with heavily pretreated metastatic gastric cancer by analyzing the eligible data extracted under limited conditions.

CONCLUSION

This study provides clear evidence to evaluate the effectiveness and safety of trifluridine/tipiracil for patients with highly pretreated metastatic gastric cancer, and the findings will also be published in a peer-reviewed journal.

ETHICS AND DISSEMINATION

No ethical statement will be required for this study because there is no direct involvement of human. This review will be published in a peer-reviewed journal as a conference report or an article.

REGISTRATION

OSF registration number: DOI 10.17605/OSF.IO/6MF5U.

Neutropenia and survival outcomes in metastatic colorectal cancer patients treated with trifluridine/tipiracil in the RECOURSE and J003 trials

Background:

The phase II J003 (N = 169) and phase III RECOURSE (N = 800) trials demonstrated a significant improvement in survival with trifluridine (FTD)/tipiracil (TPI) versus placebo in patients with refractory metastatic colorectal cancer. This post hoc analysis investigated pharmacokinetic data of FTD/TPI exposure and pharmacodynamic markers, such as chemotherapy-induced neutropenia (CIN) and clinical outcomes.

Patients and methods:

A total of 210 patients from RECOURSE were enrolled in this substudy. A limited sampling approach was used, with three pharmacokinetic samples drawn on day 12 of cycle 1. Patients were categorized as being above or below the median area under the plasma concentration–time curve (AUC) for FTD and TPI. We conducted a post hoc analysis using the entire RECOURSE population to determine the correlations between CIN and clinical outcome. We then carried out a similar analysis on the J003 trial to validate the results.

Results:

In the RECOURSE subset, patients in the high FTD AUC group had a significantly increased CIN risk. Analyses of the entire population demonstrated that FTD/TPI-treated patients with CIN of any grade in cycles 1 and 2 had significantly longer median overall survival (OS) and progression-free survival (PFS) than patients who did not develop CIN and patients in the placebo group. Patients who required an FTD/TPI treatment delay had increased OS and PFS versus those in the placebo group and those who did not develop CIN. Similar results were obtained in the J003 cohort.

Conclusions:

In RECOURSE, patients with higher FTD drug exposure had an increased CIN risk. FTD/TPI-treated patients who developed CIN had improved OS and PFS versus those in the placebo group and those who did not develop CIN. Similar findings were reported in the J003 cohort, thus validating the RECOURSE results. The occurrence of CIN may be a useful predictor of treatment outcomes for FTD/TPI-treated patients.

ClinicalTrials.gov identifier:

NCT01607957 (RECOURSE).

Japan Pharmaceutical Information Center number:

JapicCTI-090880 (J003).

TAS-102 in gastric cancer: Development and perspectives of a new biochemically modulated fluroropyrimidine drug combination

TAS-102 is a preconstituted drug combination comprising an oral fluoropyrimidine (trifluridine, TFT) and a potent inhibitor of thymidine phosphorylase (tipiracil hydrochloride, TPI). TFT/TPI has recently received Food and Drug Administration (FDA) approval also for the treatment of gastric cancer after at least two lines of chemotherapy. The approval was based on a large phase 3 trial (TAGS), in which TAS-102 showed a 31 % decrease in the risk of death compared with placebo. Here, we review the pharmacological properties, clinical development and potential future directions of TAS-102 in gastric cancer.

Pharmacokinetics, Safety, and Preliminary Efficacy of Oral Trifluridine/Tipiracil in Chinese Patients with Solid Tumors: A Phase 1b, Open-Label Study

Purpose

Trifluridine/tipiracil (FTD/TPI) is approved in Japan, the United States (US), and Europe for metastatic colorectal cancer (mCRC) refractory to standard therapies. This Phase 1b open-label study focused on the pharmacokinetic (PK) and toxicity profiles of FTD/TPI in Chinese patients with solid tumors.

Methods

Patients with definitive histologically or cytologically confirmed advanced/metastatic solid tumors refractory to standard treatments were enrolled. FTD/TPI (35 mg/m²) was administered orally twice daily for five consecutive days, followed by a 2-day recovery. Treatment was repeated for five consecutive days, followed by a 16-day recovery. The primary objective was to assess PK characteristics of FTD, 5-trifluoromethyl-2,4 (1H,3H)-pyrimidinedione (FTY; an inactive form of FTD), and TPI, calculated from plasma concentrations. Additionally, these PK values were compared with those from similar Phase 1 studies in patients from Japan and the US, using Tukey–Kramer’s honestly significant difference (HSD) multiple comparison tests. Safety and preliminary efficacy of FTD/TPI were assessed.

Results

Fifteen patients (12 males, three females) were enrolled, most with CRC (87%). Geometric mean analysis showed that maximum plasma concentration (C_max) of FTD increased after multiple administration (from day 1 [3019.5 ng/mL] to day 12 [3693.1 ng/mL]), and the exposure (AUC_0-t) increased 2.4-fold (day 1:7796.6 ng/mL•h; day 12:18,181.3 ng/mL•h). There was no meaningful change in the exposure to FTY and TPI throughout the study. HSD tests showed comparable PK for FTD, FTY, and TPI between Chinese and Japanese patients, and comparable exposure to FTD between Chinese and US patients. Eight patients (53.3%) experienced Grade 3 treatment-emergent adverse events, most frequently anemia and fatigue (13.3%, two events each). Median progression-free survival was 1.9 months.

Conclusion

FTD/TPI had an acceptable safety and efficacy profile and PK characteristics were comparable between Chinese, Japanese, and US patients, suggesting that this treatment may be suitable for Chinese patients with refractory mCRC.

Trial Registration

This trial was registered at clinicaltrials.gov as NCT02261532.

Trifluridine/tipiracil for the treatment of metastatic gastric cancer

Introduction: Trifluridine/tipiracil is a novel oral cytotoxic chemotherapy consisting of a thymidine-based nucleoside analog, trifluridine, and a thymidine phosphorylase inhibitor, tipiracil. Trifluridine/tipiracil was approved for the treatment of metastatic colorectal cancer refractory to standard therapies. A phase II trial in Japan demonstrated that this therapy has antitumor activity and is tolerated by patients with advanced gastric cancer (AGC); as a result, the phase III TAGS trial (Trifluridine/tipiracil versus placebo in patients with heavily pretreated metastatic gastric cancer) was initiated.Area covered: Trifluridine/tipiracil has proved effective for heavily pretreated AGC and has thus been approved for use in the United States in February 2019, Japan in August 2019 and the European Union in September 2019. Detail of the phase III TAGS trial is discussed in this review.Expert opinion: Trifluridine/tipiracil after at least two previous courses of systemic chemotherapy improved rates of survival of gastric cancer; thus it has become one of the treatment options in affected patients. Currently, several clinical trials of trifluridine/tipiracil in combination with other anticancer agents such as ramucirumab (an anti-vascular endothelial growth factor receptor 2 monoclonal antibody) for patients with AGC are ongoing.

Phase I Study of Trifluridine/Tipiracil Plus Irinotecan and Bevacizumab in Advanced Gastrointestinal Tumors

PURPOSE

This two-part phase Ib trial determined the maximum tolerated dose (MTD) of the combination of trifluridine/tipiracil (FTD/TPI) and irinotecan in patients with advanced gastrointestinal tumors, and evaluated the safety, pharmacokinetics, and antitumor activity of the FTD/TPI, irinotecan, and bevacizumab triplet combination in previously treated metastatic colorectal cancer (mCRC).

PATIENTS AND METHODS

Dose escalation (3+3 design) in advanced gastrointestinal tumors was followed by expansion in mCRC. During dose escalation, patients received FTD/TPI (20-35 mg/m² twice daily; days 1-5 of a 14-day cycle) and irinotecan (120-180 mg/m²; day 1). During expansion, the MTD of FTD/TPI and irinotecan plus bevacizumab (5 mg/kg; day 1) was administered.

RESULTS

Fifty patients (26 across six dose-escalation cohorts and 24 in the expansion phase) were enrolled. Two dose-limiting toxicities (fatigue and neutropenia) were observed in the dose-escalation phase, and MTD was defined as FTD/TPI 25 mg/m² twice daily plus irinotecan 180 mg/m². In the expansion phase, 83% (20/24) experienced any-cause grade ≥3 adverse events (AEs) with the triplet combination, most frequently neutropenia (42%), leukopenia (25%), and diarrhea (12%). AEs of any-cause led to dosing interruptions, modifications, and discontinuations in 29%, 17%, and 4% of patients, respectively. No treatment-related deaths occurred. Three patients (12%) experienced partial responses and 16 (67%) patients had stable disease lasting >4 months. The median progression-free survival was 7.9 months (95% confidence interval, 5.1-13.4 months).

CONCLUSIONS

Tolerability and activity observed in this phase I trial support further investigation of the FTD/TPI-irinotecan-bevacizumab combination in previously treated mCRC.

New bioanalytical microemulsion Electrokinetic chromatography method for the simultaneous determination of Trifluridine with its metabolites and Tipiracil in rat plasma: Application to pharmacokinetic studies

A Microemulsion Electrokinetic Chromatography method coupled with diode array detector (MEEKC-DAD) was developed for the first time and found to be efficient, sensitive, and selective for the simultaneous analysis of Trifluridine (FTD), and its metabolites 5-(trifluoromethyl) uracil (FTY) and 5-carboxy-2'-deoxyuridine (5CDU), and Tipiracil (TIP) in rat plasma. Sample pre-treatment involved a simple protein precipitation from plasma using acetonitrile. The separation was achieved using a fused silica capillary (65 cm total length, 55 cm effective length and 50 µm i.d.) and a microemulsion solution consisted of 1.66% sodium dodecyl sulfate (SDS), 0.91% heptane, 6.61% 1-butanol, and 90.72% borate buffer (20 mM, pH 9.5). Electrophoretic separation was carried out at 20 °C and 20 kV. The samples were injected for 40 s at 20 mbar and detected simultaneously at 205 nm. The electrophoretic parameters indicated that the developed MEEKC-DAD method permitted complete resolution of the analytes within 13 min. The developed method was fully validated according to the FDA guidelines for bioanalytical method validation. The method was linear in the range 200-4000 ng/ml for FTD, FTY, 5CDU, and 100-1000 ng/ml for TIP. The intra/inter-day accuracy and precisions were ≤4% for all drugs. Extraction recovery and stability were also assessed and were within acceptable range. After being validated, the method was applied for the determination of the studied drugs in plasma samples collected from rats injected intraperitoneally with a combination of FTD and TIP. The results obtained were used to study the pharmacokinetics of FTD with its metabolite and TIP in rat plasma.

Decreased percentage of neutrophil is a predict factor for the efficacy of trifluridine and tipiracil hydrochloride for pretreated metastatic colorectal cancer

Background

The concentration of trifluridine in tumor DNA was strongly correlated with that of white blood cells in tumor-bearing nude mice administered trifluridine-tipiracil (TAS-102). Further, a phase I study of TAS-102 in patients with advanced solid tumors showed a significant correlation between decreased neutrophil count and the area under the concentration-time curve of trifluridine. Herein, we aimed to evaluate the association of decreased neutrophil count with the efficacy of TAS-102.

Methods

We retrospectively analyzed 40 patients with pretreated metastatic colorectal cancer who received TAS-102 at Yodogawa Christian Hospital between June 2014 and May 2018. To evaluate the association between the efficacy of TAS-102 and decreased neutrophil count, patients were grouped into 4 categories according to the decrease of neutrophil count during the first cycle of TAS-102 as follows: Category A, <25%; B, 25% to <50%; C, 50% to <75%; D, ≥75%.

Results

The rate of overall survival (OS) was significantly different between Category A and B (median: 4.1 vs. 10.1 months; P=0.04), between Category A and C (median: 4.1 vs. 10.5 months; P=0.04), and between Category A and D (median: 4.1 vs. 15.6 months; P=0.04). In the multivariate analyses, a ≥25% decrease of neutrophils [hazard ratio (HR): 0.28; 95% confidence interval (CI): 0.12-0.72; P=0.01] and Eastern Cooperative Oncology Group (ECOG) performance status (PS) 2 (HR: 3.79, 95% CI: 1.04-11.2; P=0.04) were independent prognostic factors for OS.

Conclusions

Decreased neutrophil count is a predict factor for the efficacy of TAS-102. TAS-102 treatment may be ineffective in patients with a decreased neutrophil count of <25%.

Trifluridine/Tipiracil (TAS-102) for refractory metastatic colorectal cancer in clinical practice: a feasible alternative for patients with good performance status

INTRODUCTION

Our aim was to assess efficacy and safety and prognostic factors associated with TAS-102 in clinical practice.

METHOD

Retrospective, multicenter, and observational study including patients with advanced refractory colorectal cancer who started TAS-102 between March 2016 and August 2018. The primary end point was overall survival (OS). Secondary end points included progression-free survival, toxicity and analyze prognostic factors present at the beginning of TAS-102.

RESULT

84 patients were evaluable. The median OS was 8.30 (95% CI 6.23-9.87) months and PFS was 2.62 (95% CI 2.36-3.05) months. In multivariate analysis, ECOG 0 and reduced dose combined with more cycles were associated with better prognosis. Patients with an ECOG > 0 had worse prognosis (HR 3.34, 95% CI 1.09-10.27, p = 0.035). 95.2% experienced some type of adverse effect and 45.2% had grade ≥ 3 toxicities.

CONCLUSION

Results suggest reconsidering TAS-102 in patients with ECOG > 0, something that should be investigated in prospective randomized clinical trials.

Open-label study to evaluate trifluridine/tipiracil safety, tolerability and pharmacokinetics in patients with advanced solid tumours and hepatic impairment

AIMS

Trifluridine/tipiracil (FTD/TPI) prolongs survival in refractory metastatic colorectal cancer, but limited data exist on its use in patients with hepatic impairment. This Phase I, open-label, nonrandomized study investigated the safety, tolerability and pharmacokinetics of FTD/TPI in patients with advanced solid tumours (except breast cancer) and varying degrees of hepatic impairment, to provide dosing recommendations.

METHODS

Patients aged ≥18 years with advanced solid tumours and normal hepatic function, or mild, moderate or severe hepatic impairment according to National Cancer Institute criteria, were planned to be enrolled. Patients received FTD/TPI 35 mg/m² orally twice daily on days 1-5 and 8-12 of each 28-day cycle.

RESULTS

Twenty-four patients were enrolled to the normal hepatic function (n = 8) and mild (n = 10) and moderate (n = 6) hepatic impairment cohorts. Overall, 12 patients (50.0%) had at least 1 adverse event leading to study discontinuation. In the moderate hepatic impairment cohort, 5 of 6 patients experienced grade ≥ 3 elevation in bilirubin. No patients with severe hepatic impairment were enrolled. FTD area under the curve at steady state decreased by 18% and 22% in the mild and moderate cohorts, respectively; however, no clear change was observed in TPI area under the curve.

CONCLUSIONS

FTD/TPI can be safely administered in patients with normal hepatic function and mild hepatic impairment, with no initial dose adjustment. FTD/TPI is not recommended for use in patients with moderate hepatic impairment because of findings of grade 3 or 4 increased blood bilirubin. Therefore, FTD/TPI is not recommended for patients with moderate or severe hepatic impairment.

A phase I study to determine the maximum tolerated dose of trifluridine/tipiracil and oxaliplatin in patients with refractory metastatic colorectal cancer: LUPIN study

Background The effectiveness of reintroducing oxaliplatin for metastatic colorectal cancer (mCRC) refractory to both oxaliplatin and irinotecan was previously reported in a phase II study (RE-OPEN). We conducted a phase I study to determine the maximum tolerated dose of oxaliplatin plus trifluridine/tipiracil (FTD/TPI) in patients with refractory mCRC. Patients and Methods Three dosages of intravenous oxaliplatin (50, 65 and 85 mg/m²) on days 1 and 15 and a fixed dose of FTD/TPI 35 mg/m² twice daily (bid) on days 1-5 and 15-19 every 4 weeks were investigated in patients with refractory mCRC using a 3 + 3 design. Eligible patients had received prior oxaliplatin-based treatment that achieved a response or stable disease followed by confirmed disease progression at least 6 months before entering the study. Results Twelve patients were enrolled in the study. Three of six patients in the oxaliplatin 85 mg/m² cohort had dose-limiting toxicities (DLTs) with treatment delays during the second cycle at ≥8 days due to grade ≥ 2 neutropenia or grade 2 AST/ALT increased. No DLTs were observed in the other cohorts. Grade ≥ 3 AEs were neutropenia (n = 3), thrombocytopenia (n = 1), anorexia (n = 1), and nausea (n = 1). There was no evidence of allergic reaction to oxaliplatin or severe peripheral sensory neuropathy. Conclusions A combination of FTD/TPI 35 mg/m² bid on days 1-5 and 15-19 and oxaliplatin 85 mg/m² on days 1 and 15 every 4 weeks could be a suitable regimen for the recommended dose of FTD/TPI plus oxaliplatin in patients with refractory mCRC.

Trifluridine/Tipiracil (TAS-102) in Refractory Metastatic Colorectal Cancer: A Multicenter Register in the Frame of the Italian Compassionate Use Program

BACKGROUND

TAS-102 is indicated for patients with metastatic colorectal cancer (mCRC) previously treated with, or not considered candidates for, available therapies. Given the complete inefficacy in half of patients, the lack of predictive factors, the palliative setting, and the financial and clinical toxicity, optimizing the cost-benefit ratio is crucial. The "ColonLife" nomogram allows an estimate of the 12-week life expectancy of patients with refractory mCRC.

MATERIALS AND METHODS

We collected data from patients treated at eight Italian centers in the compassionate use program. Baseline characteristics of patients who were or were not progression free at 6 months were compared. The discriminative ability of the ColonLife nomogram was assessed. Among patients who received both TAS-102 and regorafenib, clinical outcomes of the two sequences were compared.

RESULTS

This study included 341 patients. Six (2%) and 93 (27%) patients achieved response and disease stabilization, respectively. The median progression-free survival (PFS) was 2.4 months with an estimated 6-month PFS rate of 19%; the median overall survival (OS) was 6.2 months. An Eastern Cooperative Oncology Group performance status (ECOG PS) of 0, normal lactate dehydrogenase (LDH), and a time from the diagnosis of metastatic disease of >18 months were independently associated with higher chances of a patient being progression free at 6 months. The discriminative ability of ColonLife was confirmed. Among 121 patients who received both regorafenib and TAS-102, no differences in first or second PFS or OS were reported between the two sequences.

CONCLUSION

One out of five patients achieves clinical benefit with TAS-102. ECOG PS, LDH, and time from diagnosis of metastatic disease may help to identify these patients. Excluding patients with very short life expectancy appears a reasonable approach.

IMPLICATIONS FOR PRACTICE

Improving the cost-efficacy ratio of TAS-102 in metastatic colorectal cancer is needed to spare useless toxicities in a definitely palliative setting. Eastern Cooperative Oncology Group performance status, lactate dehydrogenase levels, and time from the diagnosis of metastatic disease may help to identify patients more likely to achieve benefit. Properly designed prognostic tools (i.e., the "ColonLife" nomogram) may enable excluding from further treatments patients with very limited life expectancy.

[Fluoropyrimidines cardiac toxicity: 5-fluorouracil, capecitabine, compound S-1 and trifluridine/tipiracil]

The incidence of cardiac toxicity of 5-flurorouracil (5-FU) IV and capecitabine varies from 1.2 to 18%. The physiopathology of this toxicity is still under study, various hypotheses are mentioned. In the absence of identified prophylactic treatment, reintroduction of this cytotoxic is at risk. A discussion between oncologists and cardiologists is essential to estimate the balance between benefit and risk and the careful reintroduction of treatment. An alternative compound might be raltitrexed which is currently the treatment recommended in case of intolerance to fluoropyrimidines. The compound S-1 does not have any cardiac toxicity. Of a total of 2910 patients in phase II or III studies, no grade III or IV cardiovascular events were reported. However, the treatment is not reimbursed in France and therefore not available. The trifluridine/tipiracil, for which approval from French authorities was obtained in November 2016 for patients with metastatic colorectal cancer in progress despite standard treatment lines, does not appear to have cardiac toxicity according to studies published to date. The pivotal phase III study (RECOURSE), that led to this marketing authorization, was performed in 800 patients with metastatic colorectal cancer refractory and only one patient (less than 1% of patients) treated with trifluridine/tipiracil presented an episode of cardiac ischemia. Thus, trifluridine/tipiracil, which is well tolerated, could be an alternative to raltitrexed for patients with cardiovascular history contraindicating or discouraging the use of fluoropyrimidines.

Trifluridine/tipiracil overcomes the resistance of human gastric 5-fluorouracil-refractory cells with high thymidylate synthase expression

Trifluridine/tipiracil (FTD/TPI or TFTD, also known as TAS-102) is a combination of the antineoplastic thymidine analog, FTD, and thymidine phosphorylase inhibitor, TPI (molar ratio 1:0.5). FTD/TPI was approved in Japan, the United States, and the European Union for the treatment of unresectable advanced or recurrent colorectal cancer. We evaluated the in vitro and in vivo efficacy and mechanisms of action of FTD and FTD/TPI against 5-fluorouracil (5-FU)-resistant MKN45/5FU, MKN74/5FU, and KATOIII/5FU human gastric cancer cells overexpressing thymidylate synthase (TS) and their respective parent cell lines. MKN45/5FU and KATOIII/5FU cells were not cross-resistant to FTD, whereas MKN45/5FU cells were 3.7-fold more resistant than the parental cells in vitro. FTD was also incorporated into genomic DNA in a concentration-dependent manner in 5-FU-resistant and parental cells. Additionally, deoxyuridine monophosphate levels in MKN45/5FU cells after 24-h FTD treatment were 3.0-fold higher than those in parental cells, and FTD treatment for 72 h induced G2/M arrest in MKN45/5FU cells, unlike the S phase arrest in MKN45 cells. Thus, TS-overexpressing MKN45/5FU cells, but not MKN74/5FU and KATOIII/5FU cells, showed partial cross-resistance to FTD. However, FTD/TPI (administered orally twice a day) exhibited antitumor activity to the same extent in MKN45 and MKN45/5FU xenograft mouse models, overcoming in vitro cross-resistance to FTD. DNA incorporation rather than TS inhibition seems to be the main action of FTD under these in vivo conditions. Thus, FTD/TPI is a promising chemotherapeutic agent against gastric cancers recurring following 5-FU therapy.

The subgroups of the phase III RECOURSE trial of trifluridine/tipiracil (TAS-102) versus placebo with best supportive care in patients with metastatic colorectal cancer

BACKGROUND

In the phase III RECOURSE trial, trifluridine/tipiracil (TAS-102) extended overall survival (OS) and progression-free survival (PFS) with an acceptable toxicity profile in patients with metastatic colorectal cancer refractory or intolerant to standard therapies. The present analysis investigated the efficacy and safety of trifluridine/tipiracil in RECOURSE subgroups.

METHODS

Primary and key secondary end-points were evaluated using a Cox proportional hazards model in prespecified subgroups, including geographical subregion (United States of America [USA], European Union [EU], Japan), age (<65 years, ≥65 years) and v-Ki-ras2 Kirsten rat sarcoma 2 viral oncogene homologue (KRAS) status (wild type, mutant). Safety and tolerability were reported with descriptive statistics.

RESULTS

Eight-hundred patients were enrolled: USA, n = 99; EU, n = 403; Japan, n = 266. Patients aged ≥65 years and those with mutant KRAS tumours comprised 44% and 51% of all patients in the subregions, respectively. Final OS analysis (including 89% of events, compared with 72% in the initial analysis) confirmed the survival benefit associated with trifluridine/tipiracil, with a hazard ratio (HR) of 0.69 (95% confidence interval [CI] 0.59-0.81; P = 0.0001). Median OS in the three regions was 6.5-7.8 months in the trifluridine/tipiracil arm and 4.3-6.7 months in the placebo arm (USA: HR 0.56; 95% CI 0.34-0.94; P = 0.0277; EU: HR 0.62; 95% CI 0.48-0.80; P = 0.0002; Japan: HR 0.75; 95% CI 0.57-1.00; P = 0.0470). Median PFS was 2.0-2.8 months for trifluridine/tipiracil and 1.7-1.8 months for placebo; HRs favoured trifluridine/tipiracil in all regions. Similar clinical benefits of trifluridine/tipiracil were observed in elderly patients and in those with mutant KRAS tumours. There were no marked differences among subregions in terms of safety and tolerability.

CONCLUSIONS

Trifluridine/tipiracil was effective in all subgroups, regardless of age, geographical origin or KRAS status. This trial is registered with ClinicalTrials.gov: NCT01607957.

Contribution of equilibrative nucleoside transporter(s) to intestinal basolateral and apical transports of anticancer trifluridine

Trifluridine (FTD) exhibits anticancer activities after its oral administration despite its hydrophilic nature. It was previously reported that concentrative nucleoside transporter (CNT) 1 mediates the apical uptake of FTD in human small intestinal epithelial cells (HIECs). In the present study, FTD was also identified as a substrate for equilibrative nucleoside transporter (ENT) 1 and ENT2 in transporter gene-transfected cells. An immunocytochemical analysis revealed that ENT1 was expressed at the basolateral and apical membranes of HIECs. Cellular accumulation increased in the presence of S-(4-nitrobenzyl)-6-thioinosine (NBMPR), an ENT selective inhibitor. Cytotoxicity in HIEC monolayers at low FTD concentrations was increased by NBMPR, and this may have been due to inhibition of the ENT-mediated basolateral transport of FTD by NBMPR. These results suggest that ENTs reduce the intestinal cytotoxicity of FTD by facilitating its basolateral efflux. On the other hand, the intracellular accumulation and cytotoxicity of FTD in HIECs were decreased at higher concentrations of FTD by NBMPR, and this may have been due to the NBMPR inhibition of the apical uptake of FTD, which has been suggested to be mediated by CNTs and ENTs. In conclusion, ENTs were responsible for intestinal transepithelial permeation by mediating the basolateral efflux of FTD after its uptake by CNT1 from the apical side, resulting in decreases in its intracellular accumulation and intestinal toxicity in humans. Equilibrative nucleoside transporters may also partially contribute to the low-affinity uptake of FTD across the apical membrane along with high-affinity CNT1.

Combined efficacy and mechanism of trifluridine and SN-38 in a 5-FU-resistant human colorectal cancer cell lines

Trifluridine/tipiracil (FTD/TPI or TFTD, also known as TAS-102) with a molar ratio of 1:0.5, is a novel combination of FTD, an antineoplastic thymidine analog, and TPI, an inhibitor of thymidine phosphorylase. It has been approved as a treatment for unresectable advanced or recurrent colorectal cancer. Irinotecan (CPT-11) is an active agent in colorectal cancer. The administration order of drugs is a critical issue in clinical combination therapy. In this study, we evaluated the in vitro simultaneous and sequential combination efficacy of FTD and SN-38, an active metabolite of CPT-11, against human colorectal 5-fluorouracil (5-FU) resistant cell line DLD-1/5-FU and the parental cells DLD-1. The sequential exposure to SN-38 for 24 h followed by sequential exposure to FTD for 24 h or vice versa was more effective for cell survival than the simultaneous exposure of both drugs for 24 h. Furthermore, compared with simultaneous exposure, sequential exposure induced DNA damage, G2/M cell cycle arrest with increasing sub-G1 positive cells, and apoptosis in both DLD-1 and DLD-1/5-FU cells. In particular, in DLD-1/5-FU cells, sequential exposure to SN-38 followed by FTD induced apoptosis more than FTD followed by SN-38. Thus, the sequential treatment with SN-38 followed by FTD may be useful for the combination therapy of FTD/TPI and CPT-11 against relapsed colorectal cancer after 5-FU-based chemotherapy.

MBD4 frameshift mutation caused by DNA mismatch repair deficiency enhances cytotoxicity by trifluridine, an active antitumor agent of TAS-102, in colorectal cancer cells

Backgrounds

Trifluridine is an active antitumor component of TAS-102 that resembles 5-fluorouracil. Although patients with advanced colorectal cancer (CRC) exhibiting a mismatch repair (MMR) deficiency reportedly do not benefit from 5-fluorouracil-based chemotherapy and we previously reported that truncated methyl-CpG binding domain protein 4 (MBD4) enhances 5-fluorouracil cytotoxicity in MMR-deficient CRC cells, little is known regarding the effect of MMR deficiency on trifluridine cytotoxicity in CRC.

Aim

We investigated whether trifluridine induces cytotoxicity in a DNA MMR-dependent manner and evaluated how truncated MBD4 alters trifluridine cytotoxicity.

Methods

We utilized the human CRC cell lines HCT116 (hMLH1-deficient cells) and HCT116+ch3 (hMLH1-restored cells) and compared their sensitivities to trifluridine. And we established 5-fluorouracil-refractory hMLH1-deficient cells and analyzed trifluridine cytotoxicity. Finally, we established truncated MBD4 overexpressed CRC cell lines, and compared trifluridine sensitivity.

Potential role of polymorphisms in the transporter genes ENT1 and MATE1/OCT2 in predicting TAS-102 efficacy and toxicity in patients with refractory metastatic colorectal cancer

BACKGROUND

Trifluridine (FTD) is an active cytotoxic component of the metastatic colorectal cancer (mCRC) drug TAS-102, and thymidine phosphorylase inhibitor (TPI) inhibits the rapid degradation of FTD. We tested whether single nucleotide polymorphisms (SNPs) in genes involved in FTD metabolism and TPI excretion could predict outcome in patients with mCRC treated with TAS-102.

PATIENTS AND METHODS

We investigated three different cohorts: a training cohort (n = 52) and a testing cohort (n = 129) both receiving TAS-102 and a control cohort (n = 52) receiving regorafenib. SNPs of TK1, ENT1, CNT1, MATE1, MATE2 and OCT2 were analysed by polymerase chain reaction-based direct DNA sequencing.

RESULTS

In the training cohort, patients with any ENT1 rs760370 G allele had a significantly longer progression-free survival (PFS; 3.5 versus 2.1 months, respectively, hazard ratio [HR] 0.44, P = 0.004) and overall survival (OS; 8.7 versus 5.3 months, respectively, HR 0.27, P = 0.003) than the A/A genotype. These findings were validated in the testing cohort (P = 0.021 and 0.009 for PFS and OS, respectively). In addition, the combination of ENT1 rs760370, MATE1 rs2289669 and OCT2 rs316019 SNPs significantly stratified patients with the risk of PFS and OS in both cohorts (P < 0.001 for PFS and OS in the training cohort; P = 0.053 and 0.025 for PFS and OS, respectively, in the testing cohort). No significant differences were observed in the control group.

CONCLUSIONS

The combination of ENT1, MATE1 and OCT2 SNPs may serve as a predictive and prognostic marker in mCRC patients treated with TAS-102.

Emerging combination therapies for metastatic colorectal cancer - impact of trifluridine/tipiracil

Patients with metastatic colorectal cancer (mCRC) are surviving longer now than ever before, but mortality rates are still high and more effective therapies are clearly needed. For patients with disease that is refractory to fluoropyrimidines, oxaliplatin, irinotecan, and biologic agents targeting the vascular endothelial growth factor and epidermal growth factor receptor pathways, novel treatment options trifluridine/tipiracil (TAS-102) and regorafenib can be effective disease stabilizers. However, objective clinical responses are rare and toxicities are manageable but common. In order to tackle poor clinical responses to TAS-102, there is an ongoing effort to effectively combine this drug with other agents, particularly those targeting angiogenesis. Certain subpopulations appear to benefit more than others from TAS-102; those that benefit often have underlying genetic defects in DNA repair pathways and/or develop neutropenia. In this review, we focus on the role of TAS-102 in the treatment of mCRC, including its use in combination with other agents, potential predictive biomarkers of response to TAS-102, and possible future directions.

Profile of trifluridine/tipiracil hydrochloride in the treatment of metastatic colorectal cancer: efficacy, safety, and place in therapy

TAS-102, with its robust survival efficacy and feasible toxicity, is one of the standard salvage-line treatments for patients with metastatic colorectal cancer (mCRC). No definitive data are available to determine which drug should be administered first during salvage-line treatment. Therefore, it is imperative that we establish the sequence of administration by considering drug toxicity profiles based on patient characteristics, such as age, performance status, comorbidities, tolerability to previous treatments, and patient preferences. The identification of predictive biomarkers in response to TAS-102 or its toxicity is urgently needed for better patient selection. Moreover, to strengthen efficacy or relieve toxicity, combinations with other agents, which could potentially emerge as standard treatment regimens, have been investigated and compared to existing active regimens for mCRC.

Trifluridine/Tipiracil: A Review in Metastatic Colorectal Cancer

Trifluridine/tipiracil (Lonsurf(®)) is a novel, orally active, antimetabolite agent comprised of trifluridine, a thymidine-based nucleoside analogue, and tipiracil, a potent thymidine phosphorylase inhibitor. Trifluridine is incorporated into DNA via phosphorylation, ultimately inhibiting cell proliferation. Tipiracil increases systemic exposure of trifluridine when coadministered. Trifluridine/tipiracil has recently been approved for the treatment of adult patients with metastatic colorectal cancer (mCRC) who are refractory to or are not considered candidates for, current standard chemotherapy and biological therapy in the EU and USA and in unresectable advanced or recurrent CRC in Japan. The approved regimen of oral twice-daily trifluridine/tipiracil (35 mg/m(2) twice daily on days 1-5 and 8-12 of each 28-day cycle) significantly improved overall survival and progression-free survival and was associated with a significantly higher disease control rate than placebo when added to best supportive care in the multinational, pivotal phase III trial (RECOURSE) and a phase II Japanese trial. Trifluridine/tipiracil was associated with an acceptable tolerability profile, with adverse events generally being managed with dose reductions, temporary interruptions in treatment or administration of granulocyte-colony stimulating factor. The most common grade 3-4 adverse events (≥10 %) were anaemia, neutropenia, thrombocytopenia and leukopenia. In conclusion, trifluridine/tipiracil is a useful additional treatment option for the management of mCRC in patients who are refractory to, or are not considered candidates for, currently available therapies.

A phase 1 study of the pharmacokinetics of nucleoside analog trifluridine and thymidine phosphorylase inhibitor tipiracil (components of TAS-102) vs trifluridine alone

Background Trifluridine, a thymidine-based chemotherapeutic, has limited bioavailability after clinical administration as it is rapidly degraded via thymidine phosphorylase. An oral combination tablet combines trifluridine with a potent thymidine phosphorylase inhibitor, tipiracil hydrochloride. This study’s objective was to evaluate whether trifluridine/tipiracil (TAS-102) administration increases trifluridine exposure vs trifluridine alone. Methods This open-label pharmacokinetic study randomly assigned patients with advanced solid tumors into two groups. On the morning of day 1, one group received a single 35 mg/m² dose of trifluridine/tipiracil and the other group received a single 35-mg/m² dose of trifluridine. Both groups received trifluridine/tipiracil 35 mg/m² on the evening of day 1, then twice daily on days 2–5 and 8–12 in a 28-day cycle. Results Twenty patients received an initial one-time dose of trifluridine alone and 19 other patients received an initial dose of trifluridine/tipiracil. Trifluridine area under the curve (AUC_0-last) and maximum observed plasma concentrations (C_max) were approximately 37- and 22-fold higher, respectively, with trifluridine/tipiracil vs trifluridine alone. Plasma concentrations of the major metabolite of trifluridine were lower following the administration of trifluridine/tipiracil vs trifluridine alone. Conclusion Tipiracil administered in combination with trifluridine significantly increased exposure to trifluridine compared with trifluridine alone.

Metabolism, Biochemical Actions, and Chemical Synthesis of Anticancer Nucleosides, Nucleotides, and Base Analogs

Nucleoside, nucleotide, and base analogs have been in the clinic for decades to treat both viral pathogens and neoplasms. More than 20% of patients on anticancer chemotherapy have been treated with one or more of these analogs. This review focuses on the chemical synthesis and biology of anticancer nucleoside, nucleotide, and base analogs that are FDA-approved and in clinical development since 2000. We highlight the cellular biology and clinical biology of analogs, drug resistance mechanisms, and compound specificity towards different cancer types. Furthermore, we explore analog syntheses as well as improved and scale-up syntheses. We conclude with a discussion on what might lie ahead for medicinal chemists, biologists, and physicians as they try to improve analog efficacy through prodrug strategies and drug combinations.

Interstitial pneumonia in a patient treated with TAS-102 for metastatic colorectal cancer: a case report

Background

TAS-102, a new treatment option for patients with metastatic colorectal cancer that is refractory or intolerant to standard therapies, has been improving survival with acceptable tolerability and adverse events. Adverse hematological events associated with TAS-102 treatment were extensively profiled in the RECOURSE trial, but pulmonary toxicities associated with TAS-102 therapy are distinctly uncommon. In a recent early post-marketing phase vigilance on TAS-102 in Japan, seven cases of pulmonary disease were reported, but patient follow-up in this study was incomplete. Here, we present the first case of interstitial lung disease occurring in association with TAS-102 treatment.

Case presentation

A 57-year-old Japanese man who had previously received two standard treatments was admitted in 2014, at which time we administered TAS-102 (110 mg/day) as a third-line chemotherapy. He was safely treated with TAS-102 for the first planned cycle; however, approximately 4 days after receiving the second cycle of TAS-102, he complained of high fever and subsequent dyspnea with severe hypoxemia and went to the emergency room. A chest X-ray revealed diffuse coarse reticular shadows with ground-glass opacity on both lungs. Furthermore, a chest computed tomography scan showed thickening of the bronchovascular bundles with extensive ground-glass opacification and pleural effusions in both lung fields.

In addition, a peripheral blood lymphocyte stimulation test with TAS-102 showed higher values compared with control samples. Consequently, we suspected drug-induced interstitial pneumonia, and discontinued treatment. Our patient was given an initial administration of high-dose methylprednisolone (1000 mg/day) for 3 days and oxygen. Our patient was discharged with oral prednisolone (20 mg/day) and improved symptomatically and radiologically.

Conclusions

These findings suggest that interstitial pneumonia is a rare complication of TAS-102 chemotherapy, but the possibility of interstitial pneumonia should always be considered when a patient presents with a respiratory disorder while undergoing TAS-102 systemic chemotherapy.

Prompt discontinuation of TAS-102 and treatment with high-dosage corticosteroids is needed to avoid exacerbating respiratory symptoms.

Neutropenia as a Predictive Factor in Metastatic Colorectal Cancer Treated With TAS-102

BACKGROUND

TAS-102 significantly improves overall survival in patients with metastatic colorectal cancer. The most common treatment-related adverse event of TAS-102 is bone marrow suppression, which leads to neutropenia. The potential predictive value of neutropenia caused by cytotoxic drugs has been reported in various types of cancer.

METHODS

We retrospectively analyzed 95 consecutive patients with metastatic colorectal cancer who received TAS-102 at 2 Japanese institutions between May 2014 and May 2015. To evaluate the association between efficacy and neutropenia, patients were divided into 4 categories according to the grade of neutropenia during the first cycle of TAS-102: Category A (grade 0-1), B (grade 2-4), C (grade 0-2), and D (grade 3-4).

RESULTS

Patient characteristics were as follows: median age, 64 years; male, 58%; Eastern Cooperative Oncology Group performance status 0 to 1, 91%; primary site colon, 49%; KRAS exon 2 wild, 57%; and number of metastatic site ≥ 3, 55%. The disease control rate was significantly different between Category A and B (29.2% vs. 52.6%; P = .045) and between Category C and D (30.9% vs. 72.2%; P = .002). In multivariate analysis, Category D remained a significant predictive factor for progression-free survival compared with Category C (4.3 vs. 2.0 months; hazard ratio, 0.45; P = .01).

CONCLUSION

Neutropenia caused by TAS-102 during the first cycle was associated with better efficacy. Neutropenia may be a surrogate marker for adequate antitumor doses of TAS-102.

Efficacy of trifluridine and tipiracil (TAS-102) versus placebo, with supportive care, in a randomized, controlled trial of patients with metastatic colorectal cancer from Spain: results of a subgroup analysis of the phase 3 RECOURSE trial

Purpose

TAS-102 is a combination of the thymidine-based nucleoside analog trifluridine and the thymidine phosphorylase inhibitor tipiracil. Efficacy and safety of TAS-102 in patients with metastatic colorectal cancer (mCRC) refractory or intolerant to standard therapies were evaluated in the phase 3 RECOURSE trial. Results of RECOURSE demonstrated significant improvement in overall survival (OS) and progression-free survival (PFS) with TAS-102 versus placebo [hazard ratio (HR) = 0.68 and 0.48 for OS and PFS, respectively; both P < 0.001]. The current analysis evaluates efficacy and safety of TAS-102 in the RECOURSE Spanish subgroup.

Methods

Primary and key secondary endpoints were evaluated in a post hoc analysis of the RECOURSE Spanish subgroup, using univariate and multivariate analyses. Safety and tolerability were reported with descriptive statistics.

Results

The RECOURSE Spanish subgroup included 112 patients (mean age 61 years, 62 % male). Median OS was 6.8 months in the TAS-102 group (n = 80) versus 4.6 months in the placebo group (n = 32) [HR = 0.47; 95 % confidence interval (CI): 0.28–0.78; P = 0.0032). Median PFS was 2.0 months in the TAS-102 group and 1.7 months in the placebo group (HR = 0.47; 95 % CI: 0.30–0.74; P = 0.001). Eighty (100 %) TAS-102 versus 31 (96.9 %) placebo patients had adverse events (AEs). The most common drug-related ≥Grade 3 AE was neutropenia (40 % TAS-102 versus 0 % placebo). There was 1 (1.3 %) case of febrile neutropenia in the TAS-102 group versus none in the placebo group.

Conclusions

In the RECOURSE Spanish subgroup, TAS-102 was associated with significantly improved OS and PFS versus placebo, consistent with the overall RECOURSE population. No new safety signals were identified.

ClinicalTrials.gov study number

NCT01607957

Chemotherapy induced neutropenia at 1-month mark is a predictor of overall survival in patients receiving TAS-102 for refractory metastatic colorectal cancer: a cohort study

Background

TAS-102 (trifluridine and tipiracil hydrochloride; a novel combination oral nucleoside anti-tumor agent) has recently received regulatory approval for patients with refractory metastatic colorectal cancer (mCRC). Internal review of data at a single-institution showed a trend towards better overall survival (OS) for patients who experienced chemotherapy-induced neutropenia at 1-month (CIN-1-month). To explore this finding further, a cohort study was designed based on outcome data from three centers in United States and one from Japan.

Methods

CIN-1-month after starting TAS-102 was defined by the Common Terminology Criteria for Adverse Events (CTCAE), version 4.03 as a neutrophil count decrease of ≥ grade 2 (absolute neutrophil count < 1500/mm³). Patients had confirmed mCRC that was refractory to standard therapies. Patient demographics and clinical characteristics were compared between patients with CIN-1-month (CIN-1-month positive) versus those who did not have CIN-1-month (CIN-1-month negative); with the median progression-free survival (PFS) and OS were calculated using the Kaplan-Meier method, and differences evaluated using the Log-rank test.

Results

Our cohort study had a total of 149 patients with data regarding their neutrophil assessment at 1-month mark. Patients who developed ≥ grade 2 CIN-1-month had a both longer PFS (median 3.0 months versus 2.4 months; Log-rank P-value = 0.01), as well as OS (14.0 versus 5.6 months; Log-rank P-value < 0.0001). Only CIN-1-month (adjusted HR: 0.21 (95 % CI: 0.11–0.38) and higher baseline CEA levels (adjusted HR: 2.00 (95 % CI: 1.22–3.35) were noted to be independent predictors of OS. Furthermore, the CIN-1-month was noted to be a statistically significantly predictor of OS over a wide range of cutoffs.

Conclusions

Our observations are novel and hypothesis generating. Neutropenia after starting TAS-102 was associated with better prognosis in patients with refractory mCRC. It can be postulated that the dosage of TAS-102 potentially may need to be increased to achieve better outcomes in patients not experiencing any neutropenia. Further pharmacologic investigations should help elucidate these issues.