TAS-102 for Treatment of Advanced Colorectal Cancers That Are No Longer Responding to Other Therapies

Simultaneous determination of tipiracil, trifluridine and its metabolite 5-trifluoromethyluracil in human plasma using segmented polarity LC-MS/MS: A fully validated assay with clinical application

Trifluridine (FTD) and tipiracil (TPI) hydrochloride tablets (TAS-102) were used for the treatment of patients with metastatic rectal cancer that was resistant to conventional chemotherapy drugs. In this study, a rapid and sensitive liquid chromatography-tandem mass spectrometry method was developed and fully validated for the simultaneous determination of TPI, FTD, and the metabolite 5-trifluoromethyluracil (FTY) of FTD in human plasma. The plasma samples were prepared by protein precipitation. The chromatography separation was performed using ACE Excel 3 AQ (100 × 2.1 mm i.d., 1.7 µm, ACE, England) column protected by a security guard cartridge (4.0 × 2.0 mm i.d., 5 µm, Phenomenex, USA) with a gradient elution of 0.05% acetic acid in water and methanol at a flow rate of 0.35 mL/min. The MS/MS analysis was performed by using multiple reaction monitoring with the segmented polarity (positive for TPI: m/z 243.1→183.0, and negative for FTD: m/z 295.1→252.0 and FTY: m/z 178.9→158.9) electrospray ionization mode. The segmented polarity mode was designed to achieve two advantages: better sensitivity and simultaneous determination of the analytes with different ion polarities. The calibration ranges were as follows: 1.00-250 ng/ for TPI, 8.00-8000 ng/mL for FTD and 5.00-1250 ng/mL for FTY. The selectivity, accuracy, precision, matrix effect, recovery, carryover, dilution integrity and stability test results meet ICH acceptance criteria. The method was evaluated using the RGB model and successfully applied to a clinical study in patients with solid tumors. For TPI, FTD and FTY, the maximum plasma concentration was 137-147 ng/mL, 6160-6240 ng/mL and 724-725 ng/mL, respectively; the plasma elimination half-life was 1.69-1.78 h, 1.70 h, and 3.09-3.14 h, respectively, after an oral administration of 60 mg TAS-102.

Efficacy and safety of trifluridine/tipiracil (TAS-102) in patients with metastatic colorectal cancer: a systematic review and meta-analysis

OBJECTIVES

The purpose of this meta-analysis is to evaluate the efficacy and safety of TAS-102 in treating metastatic colorectal cancer (mCRC) using the most recent data available.

METHODS

The literature on the efficacy and safety of TAS-102 versus placebo and/or best supportive care (BSC) in mCRC was obtained through a systematic search of PubMed, Embase, and Web of Science databases through January 2023. Identify the included literature and extract pertinent data, such as the overall survival (OS), progression-free survival (PFS), time to treatment failure (TTF), disease control rate (DCR), incidence of adverse events (AEs) and serious adverse events (SAEs).

RESULTS

There were eight eligible articles that included 2903 patients (1964 TAS-102 versus 939 Placebo and/or BSC). In this meta-analysis, TAS-102 treatment resulted in longer OS, PFS, TTF, and higher DCR in patients with mCRC versus placebo and/or BSC. TAS-102 improved OS and PFS in subgroup analyses of mCRC patients with KRAS wild-type and KRAS mutant-type. In addition, TAS-102 did not increase the incidence of serious adverse events.

CONCLUSION

TAS-102 can enhance the prognosis of mCRC patients whose standard therapy has failed, regardless of KRAS mutation status, and its safety is acceptable.

Small-molecule inhibitors, immune checkpoint inhibitors, and more: FDA-approved novel therapeutic drugs for solid tumors from 1991 to 2021

The United States Food and Drug Administration (US FDA) has always been a forerunner in drug evaluation and supervision. Over the past 31 years, 1050 drugs (excluding vaccines, cell-based therapies, and gene therapy products) have been approved as new molecular entities (NMEs) or biologics license applications (BLAs). A total of 228 of these 1050 drugs were identified as cancer therapeutics or cancer-related drugs, and 120 of them were classified as therapeutic drugs for solid tumors according to their initial indications. These drugs have evolved from small molecules with broad-spectrum antitumor properties in the early stage to monoclonal antibodies (mAbs) and antibody‒drug conjugates (ADCs) with a more precise targeting effect during the most recent decade. These drugs have extended indications for other malignancies, constituting a cancer treatment system for monotherapy or combined therapy. However, the available targets are still mainly limited to receptor tyrosine kinases (RTKs), restricting the development of antitumor drugs. In this review, these 120 drugs are summarized and classified according to the initial indications, characteristics, or functions. Additionally, RTK-targeted therapies and immune checkpoint-based immunotherapies are also discussed. Our analysis of existing challenges and potential opportunities in drug development may advance solid tumor treatment in the future.

RETRACTED: Comparison between diagnostic performance of intestinal Fusobacterium nucleatum, Bacteroides fragilis and Escherichia coli in 5-fluorouracil resistance to colorectal cancer: A meta‑analysis

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the authors, as the current findings are incomplete and need to be validated. The reasons include that the results are not comparable to the diagnostic performance of three bacteria species in 5-fluorouracil resistance in CRC from the clinical studies which are conducted to detect each type of bacteria separately. Additional results of quantifying three bacteria species in the same colorectal cancer group are required to validate the conclusion.

Radiosensitisation and enhanced tumour growth delay of colorectal cancer cells by sustained treatment with trifluridine/tipiracil and X-rays

Trifluridine/tipiracil (FTD/TPI; marketed as Lonsurf®) has shown clinically relevant activity after fluoropyrimidine failure in colorectal cancer and may thus be of increased efficacy compared with current standard capecitabine chemoradiation. Here we investigated the colorectal cancer cell lines HT29, HCT116, SW48 and Caco-2 to provide a preclinical rationale for FTD/TPI-based chemoradiation treatment. All lines incorporated similar amounts of FTD, irrespective of treatment concentration and duration, then arrested in S phase, showed persistent γH2AX induction and eventually underwent endoreplication, resulting in polyploidy. Clonogenic assays performed for four combined treatment schedules demonstrated additivity for treatments given within 6 h of each other. However, 24 h FTD/TPI treatment prior to irradiation caused 1.6-2.4 fold radiosensitisation. Combined in vivo treatment was well tolerated and caused a marked tumour growth delay, similar to capecitabine radiochemotherapy regimes. Prolonged S phase arrest, persistent γH2AX signalling, endoreplication and polyploidy may contribute to the cytotoxicity of FTD/TPI. The strong radiosensitising effect observed in vitro after prolonged treatment with FTD/TPI and equivalence with capecitabine-based chemoradiation in vivo support a daily fractionated combined regime of FTD/TPI and radiation in rectal cancer treatment. This is now being tested in a phase I/II clinical trial (NCT04177602).

5-fluorouracil and other fluoropyrimidines in colorectal cancer: Past, present and future

5-Fluorouracil (5-FU) is an essential component of systemic chemotherapy for colorectal cancer (CRC) in the palliative and adjuvant settings. Over the past four decades, several modulation strategies including the implementation of 5-FU-based combination regimens and 5-FU pro-drugs have been developed and tested to increase the anti-tumor activity of 5-FU and to overcome the clinical resistance. Despite the encouraging progress in CRC therapy to date, the patients' response rates to therapy continue to remain low and the patients' benefit from 5-FU-based therapy is frequently compromised by the development of chemoresistance. Inter-individual differences in the treatment response in CRC patients may originate in the unique genetic and epigenetic make-up of each individual. The critical element in the current trend of personalized medicine is the proper comprehension of causes and mechanisms contributing to the low or lack of sensitivity of tumor tissue to 5-FU-based therapy. The identification and validation of predictive biomarkers for existing 5-FU-based and new targeted therapies for CRC treatment will likely improve patients' outcomes in the future. Herein we present a comprehensive review summarizing options of CRC treatment and the mechanisms of 5-FU action at the molecular level, including both anabolic and catabolic ways. The main part of this review comprises the currently known molecular mechanisms underlying the chemoresistance in CRC patients. We also focus on various 5-FU pro-drugs developed to increase the amount of circulating 5-FU and to limit toxicity. Finally, we propose future directions of personalized CRC therapy according to the latest published evidence.

HER2-targeted therapy: an emerging strategy in advanced colorectal cancer

INTRODUCTION

Colorectal cancer (CRC) is one of the most common malignant tumors; it is a focus of research globally, but the identification of clinically actionable oncogenic drivers remains elusive. Human epidermal growth factor receptor 2 (HER2) activation is present in approximately 5% of CRC and has acquired resistance to epidermal growth factor receptor (EGFR)-targeted therapy. Early clinical trials suggest an emerging role for personalized HER2-targeted therapy in a subset of metastatic CRC.

AREAS COVERED

This manuscript reviews the relevance of HER2 activation in CRC and its potential role as a target for therapy. A literature search was conducted in June 2018 of MEDLINE and EMBASE databases for published preclinical and clinical studies; abstracts of international cancer meetings (AACR, ASCO, and ESMO) were also reviewed.

EXPERT OPINION

HER2 is activated in a small but relevant proportion of CRC patients (particularly left-side, RAS wild-type, anti-EGFR resistant tumors). Dual HER2 blockade with monoclonal antibodies (mAbs) (trastuzumab and pertuzumab) or the combination of mAbs with tyrosine kinase inhibitors (trastuzumab and lapatinib) induces durable tumor responses in about one-third of HER2-positive CRC refractory to standard systemic therapy. Although immature, these results are remarkable and anticipate an expanding role for HER2 as a therapeutic target in CRC.

Feasibility of 7-T fluorine magnetic resonance spectroscopic imaging (19F MRSI) for TAS-102 metabolite detection in the liver of patients with metastatic colorectal cancer

Trifluridine/tipiracil (TAS-102) has shown a significant overall survival benefit in patients with heavily pre-treated metastatic colorectal cancer. However, predicting treatment response and toxicity in individual patients remains challenging. Fluorine (¹⁹F)-containing drugs can be detected with magnetic resonance spectroscopy (MRS) to determine the metabolic rates and the biodistribution of the drug in normal and tumour tissue, which are related to treatment efficacy and toxicity. This is the first study to investigate the potential of 7-T ¹⁹F-MRS to detect TAS-102 metabolites in humans. We demonstrate that, with the used setup, TAS-102 is not detectable in liver metastases of metastatic colorectal cancer patients on a normal treatment schedule. Therefore, ¹⁹F-MRS TAS-102 metabolite detection is not yet useful for the clinical early prediction of treatment response. As ¹⁹F-MRS is able to detect TAS-102 in phantom and murine models, the use of ¹⁹F-MRS remains a potential tool to noninvasively detect and possibly monitor the metabolism when higher dosages of TAS-102 are administered, for example in organoid and animal studies.

Efficacy and safety of TAS-102 in refractory metastatic colorectal cancer: a meta-analysis

Background

TAS-102 has been applied to metastatic colorectal cancer (mCRC) patients who had received at least two prior regimens of standard chemotherapy. This meta-analysis is designed to assess the efficacy and safety of TAS-102 in patients with mCRC.

Methods

We searched randomized controlled trials (RCTs) through PubMed, Embase, Web of Science and Cochrane clinical trial databases and clinicaltrial.gov from database initiation to March 2018. The overall survival (OS), progression-free survival (PFS), disease control rate (DCR) and incidence of adverse events were summarized with the use of hazard ratio (HR) or risk ratio (RR).

Results

Three RCTs with 1318 patients were included. Results showed that TAS-102 significantly improved OS (HR 0.70, 95% confidence interval [CI] 0.62-0.79) and PFS (HR 0.46, 95% CI 0.40-0.52) in patients who were intolerant or refractory to fluoropyrimidine, irinotecan and oxaliplatin. The pooled odds ratio of DCR was 4.15 (95% CI 3.18-5.43). Notably, there were significant OS benefits both in patients with KRAS mutation (HR 0.76, 95% CI 0.63-0.92) and those with wild-type KRAS (HR 0.66, 95% CI 0.55-0.79). These benefits were also observed in patients with different numbers of metastatic sites. However, patients with >18 months since the diagnosis of first metastases seemed to have better OS (HR 0.65, 95% CI 0.55-0.77). The most common toxicities associated with TAS-102 were neutropenia (RR 116.51, 95% CI 23.51-577.33), leucopenia (RR 67.70, 95% CI 13.63-336.29), anemia (RR 4.28, 95% CI 2.70-6.79) and diarrhea (RR 5.10, 95% CI 1.40-18.61).

Conclusion

TAS-102 significantly improves OS, PFS and DCR in refractory mCRC patients with tolerable toxicity. Meanwhile, the OS benefits have nothing to do with KRAS status and the number of metastatic sites.

Panitumumab interaction with TAS-102 leads to combinational anticancer effects via blocking of EGFR-mediated tumor response to trifluridine

Panitumumab is a monoclonal antibody developed against the human epidermal growth factor receptor (EGFR). TAS-102 is a novel chemotherapeutic agent containing trifluridine (FTD) as the active cytotoxic component. Both panitumumab and TAS-102 have been approved for the treatment of metastatic colorectal cancer. In this study, we revealed the mechanism underlying the anticancer effects of panitumumab/TAS-102 combination using preclinical models. Panitumumab/FTD cotreatment showed additive antiproliferative effects in LIM1215 and synergistic antiproliferative effects in SW48 colon cancer cells. Consistent with the in vitro effects, panitumumab/TAS-102 combination caused tumor regression in LIM1215 and COL-01-JCK colon cancer patient-derived xenograft models. In LIM1215 cells, FTD induced extracellular signal-regulated kinase (ERK)/protein kinase B (AKT)/signal transducer and activator of transcription 3 (STAT3) phosphorylation and subsequent serine/threonine phosphorylation of EGFR, while it had no effects on EGFR tyrosine phosphorylation. Panitumumab and the tyrosine kinase inhibitor erlotinib reduced the basal level of EGFR tyrosine phosphorylation and reversed FTD-induced ERK/AKT/STAT3 and EGFR serine/threonine phosphorylation. These results suggested that FTD in combination with the basal activity of EGFR tyrosine kinase induced downstream prosurvival signaling through ERK/AKT/STAT3 phosphorylation. Collectively, we propose that panitumumab interacts with FTD by targeting EGFR-mediated adaptive responses, thereby exerting anticancer effects when used in combination with TAS-102. These preclinical findings provide a compelling rationale for evaluating the combination of anti-EGFR antibodies with TAS-102 against metastatic colorectal cancer.

BCKDK of BCAA Catabolism Cross-talking With the MAPK Pathway Promotes Tumorigenesis of Colorectal Cancer

Branched-chain amino acids catabolism plays an important role in human cancers. Colorectal cancer is the third most commonly diagnosed cancer in males and the second in females, and the new global incidence is over 1.2 million cases. The branched-chain α-keto acid dehydrogenase kinase (BCKDK) is a rate-limiting enzyme in branched-chain amino acids catabolism, which plays an important role in many serious human diseases. Here we investigated that abnormal branched-chain amino acids catabolism in colorectal cancer is a result of the disease process, with no role in disease initiation; BCKDK is widely expressed in colorectal cancer patients, and those patients that express higher levels of BCKDK have shorter survival times than those with lower levels; BCKDK promotes cell transformation or colorectal cancer ex vivo or in vivo. Mechanistically, BCKDK promotes colorectal cancer by enhancing the MAPK signaling pathway through direct MEK phosphorylation, rather than by branched-chain amino acids catabolism. And the process above could be inhibited by a BCKDK inhibitor, phenyl butyrate.