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1.
Invest New Drugs ; 42(4): 462-470, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39037543

ABSTRACT

This phase 1b study aimed to evaluate the dose-limiting toxicity (DLT), maximum tolerated dose (MTD), pharmacokinetics, and preliminary efficacy of HR070803, a novel nanoliposomal formulation of irinotecan, in combination with 5-fluorouracil and leucovorin in patients with pretreated advanced solid tumors. This study consisted of dose-escalation and expansion stages. Dose escalation was performed with a traditional 3 + 3 design; patients received intravenous infusion of HR070803 from 60 to 80 mg/m2, followed by leucovorin (200 mg/m2) and 5-fluorouracil (2000 mg/m2) every 2 weeks. In the expansion stage, patients received treatments at selected tolerable dose. Fifteen patients received treatments at 60 mg/m2 (n = 12) and 80 mg/m2 (n = 3). DLTs occurred in 2 patients at 80 mg/m2 (grade 2 neutropenia that resulted in a dose delay of ≥ 7 days, n = 1; grade 3 febrile neutropenia, n = 1). The MTD was determined to be 60 mg/m2. The most frequent HR070803related adverse events included anorexia, leukopenia, neutropenia, nausea, fatigue, and diarrhea. SN-38, the active metabolite of irinotecan, exhibited lower maximum plasma concentrations and a prolonged terminal half-life when irinotecan was administered via nanoliposome compared to conventional injection. Overall, 4 patients achieved a partial response (confirmed, n = 2), and 9 had stable disease. The MTD of HR070803 was 60 mg/m2 when infused with 5-fluorouracil and leucovorin. Nanoliposomal encapsulation modified the pharmacokinetics of irinotecan and SN-38. HR070803 with 5-fluorouracil and leucovorin demonstrated a manageable safety profile and promising antitumor efficacy in advanced solid tumors. TRIAL REGISTRATION: Clinicaltrials.gov, NCT05086848. Retrospectively registered on Oct. 12, 2021.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols , Fluorouracil , Irinotecan , Leucovorin , Liposomes , Maximum Tolerated Dose , Neoplasms , Humans , Leucovorin/administration & dosage , Leucovorin/pharmacokinetics , Leucovorin/adverse effects , Leucovorin/therapeutic use , Fluorouracil/administration & dosage , Fluorouracil/pharmacokinetics , Fluorouracil/adverse effects , Female , Male , Middle Aged , Antineoplastic Combined Chemotherapy Protocols/pharmacokinetics , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Aged , Irinotecan/pharmacokinetics , Irinotecan/administration & dosage , Irinotecan/adverse effects , Neoplasms/drug therapy , Adult , Dose-Response Relationship, Drug
2.
CPT Pharmacometrics Syst Pharmacol ; 13(6): 1006-1016, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38634204

ABSTRACT

Peritoneal metastases (PM) are common in patients with colorectal cancer. Patients with PM have a poor prognosis, and for those who are not eligible for cytoreductive surgery (CRS) with or without hyperthermic intraperitoneal chemotherapy (HIPEC), palliative chemotherapy is currently the only option. Recently, we conducted a phase I trial (INTERACT) in which irinotecan was administered intraperitoneally (IP) to 18 patients ineligible for CRS-HIPEC. The primary objective was to evaluate covariates influencing the PK profile of irinotecan and SN-38 after IP administration. Secondly, a population PK model was developed to support the further development of IP irinotecan by improving dosing in patients with PM. Patients were treated with IP irinotecan every 2 weeks in combination with systemic FOLFOX-bevacizumab. Irinotecan and SN-38 were measured in plasma (588 samples) and SN-38 was measured in peritoneal fluid (267 samples). Concentration-Time data were log-transformed and analyzed using NONMEM version 7.5 using FOCE+I estimation. An additive error model described the residual error, with inter-individual variability in PK parameters modeled exponentially. The final structural model consisted of five compartments. Weight was identified as a covariate influencing the SN-38 plasma volume of distribution and GGT was found to influence the SN-38 plasma clearance. This population PK model adequately described the irinotecan and SN-38 in plasma after IP administration, with weight and GGT as predictive factors. Irinotecan is converted intraperitoneal to SN-38 by carboxylesterases and the plasma bioavailability of irinotecan is low. This model will be used for the further clinical development of IP irinotecan by providing dosing strategies.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols , Colorectal Neoplasms , Irinotecan , Peritoneal Neoplasms , Humans , Irinotecan/pharmacokinetics , Irinotecan/administration & dosage , Peritoneal Neoplasms/secondary , Peritoneal Neoplasms/drug therapy , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/pathology , Male , Middle Aged , Female , Aged , Antineoplastic Combined Chemotherapy Protocols/pharmacokinetics , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Adult , Camptothecin/analogs & derivatives , Camptothecin/pharmacokinetics , Camptothecin/administration & dosage , Camptothecin/therapeutic use , Models, Biological , Bevacizumab/pharmacokinetics , Bevacizumab/administration & dosage , Bevacizumab/therapeutic use , Leucovorin/pharmacokinetics , Leucovorin/administration & dosage , Leucovorin/therapeutic use , Fluorouracil/pharmacokinetics , Fluorouracil/administration & dosage , Injections, Intraperitoneal , Organoplatinum Compounds
3.
Clin Pharmacol Drug Dev ; 12(4): 416-423, 2023 04.
Article in English | MEDLINE | ID: mdl-36808267

ABSTRACT

The aim of this study was to compare the bioequivalence and safety of test preparation sodium levofolinate injection with reference preparations of calcium levofolinate for injection and sodium folinate for injection in China. A single-center, randomized, open-label, 3-period, crossover test was conducted on 24 healthy subjects. Plasma concentration of levofolinate, dextrofolinate, and their metabolites l-5-methyltetrahydrofolate and d-5-methyltetrahydrofolate were quantified by a validated chiral-liquid chromatography-tandem mass spectrometry method. All adverse events (AEs) were documented to evaluate safety as they occurred and evaluated descriptively. Pharmacokinetic parameters (maximum plasma concentration, time to maximum concentration, area under the plasma concentration-time curve over the dosing interval, area under the plasma concentration-time curve from time 0 to infinity, terminal elimination half-life, and terminal rate constant) of 3 preparations were calculated. A total of 8 subjects (10 cases) of AEs occurred in this trial. No serious AEs or unexpected serious adverse reactions were observed. Sodium levofolinate was bioequivalent to calcium levofolinate and sodium folinate in Chinese subjects, and the 3 preparations were all well tolerated.


Subject(s)
East Asian People , Leucovorin , Levoleucovorin , Humans , Healthy Volunteers , Therapeutic Equivalency , Levoleucovorin/chemistry , Levoleucovorin/pharmacokinetics , Leucovorin/chemistry , Leucovorin/pharmacokinetics
4.
Eur J Drug Metab Pharmacokinet ; 46(2): 317-324, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33619631

ABSTRACT

BACKGROUND AND OBJECTIVES: Irinotecan (CPT-11) is metabolized to an active metabolite 7-ethyl-10-hydroxycamptothecin (SN-38) by carboxylesterase (CES). SN-38 is then converted to the inactive metabolite SN-38 glucuronide (SN-38G) by glucuronosyltransferase 1A1 (UGT1A1). Genetic polymorphisms in UGT1A1 have been associated with altered SN-38 pharmacokinetics, which increase the risk of toxicity in patients. CPT-11 is also converted to 7-ethyl-10-[4-N-(5-aminopentanoic acid)-1-piperidino]carbonyloxycamptothecin (APC) and 7-ethyl-10-(4-amino-1-piperidino) carbonyloxycamptothecin (NPC) by cytochrome P450 3A (CYP3A), and this route also affects the plasma concentration of SN-38. We evaluated the activities of UGT1A1, CYP3A, and CES and the factors affecting the pharmacokinetics of plasma SN-38 in patients with UGT1A1 gene polymorphisms. METHODS: Three male patients aged 56, 65, and 49 years were recruited for the analysis. All patients had pancreatic cancer, received FOLFIRINOX, and had UGT1A1*6/*6 (patients 1 and 3) or *6/*28 (patient 2) genetic polymorphisms. The rate constants for evaluating the enzyme activity were determined from the measured plasma concentration of CPT-11 and its metabolites using a two-compartment model by WinNonlin. RESULTS: The area under the plasma concentration-time curve (AUC) of SN-38 was patient 1 > patient 2 > patient 3. The rate constants obtained from the model analysis indicated the respective enzyme activities of UGT1A1 (k57), CYP3A (k13 + k19), and CES (k15). The order of values for UGT1A1 activity was patient 2 > patient 3 > patient 1. Since UGT1A1 activity was low in patient 1 with a high AUC of SN-38, it can be said that the increase in plasma concentration was due to a decrease in UGT1A1 activity. Conversely, the order of values for CYP3A and CES activities was patient 3 > patient 1 > patient 2 and patient 2 > patient 1 > patient 3, respectively. Patient 3 had the lowest AUC of SN-38, caused by a lower level of CES activity and increased CYP3A activity. CONCLUSION: In this study, we indicated that the plasma AUC of SN-38 and AUC ratio of SN-38G/SN-38 may depend on changes in the activities of CYP3A, CES, and UGT1A1. Using pharmacokinetic analysis, it is possible to directly evaluate enzyme activity and consider what kind of enzyme variation causes the increase in the AUC of SN-38.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/pharmacokinetics , Glucuronosyltransferase/genetics , Irinotecan/pharmacokinetics , Pancreatic Neoplasms/drug therapy , Aged , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Area Under Curve , Camptothecin/analogs & derivatives , Camptothecin/pharmacokinetics , Carboxylesterase/metabolism , Cytochrome P-450 CYP3A/metabolism , Fluorouracil/administration & dosage , Fluorouracil/pharmacokinetics , Glucuronides/pharmacokinetics , Glucuronosyltransferase/metabolism , Humans , Irinotecan/administration & dosage , Leucovorin/administration & dosage , Leucovorin/pharmacokinetics , Male , Middle Aged , Models, Biological , Oxaliplatin/administration & dosage , Oxaliplatin/pharmacokinetics , Polymorphism, Genetic
5.
J Chemother ; 33(1): 51-55, 2021 Feb.
Article in English | MEDLINE | ID: mdl-32066346

ABSTRACT

We administered FOLFOX (oxaliplatin (L-OHP) plus infusional 5-fluorouracil (5-FU) and leucovorin) to an hemodialysis (HD) patient with advanced gastric cancer (AGC), and investigated pharmacokinetics (PKs) and dialyzability of L-OHP. The patient was a 54-year-old Japanese man with a diagnosis of inoperable AGC. FOLFOX was instituted 3 h prior to the start of a 4 h HD period with the L-OHP and 5-FU doses reduced by 50% for the first cycle, and 30% reduced dose was administered for the second cycle. We performed an analysis of the PKs of L-OHP during these two cycles. Volume of distribution and area under the curve of the 30% reduced L-OHP dose were 56.7 L and 30.0 µg·h/mL, respectively. A dose reduction of L-OHP by 30%-50% may be advisable for the initial administration, given the need for careful administration of chemotherapy in HD patients, with particular attention to the development of hematological toxicities and neuropathy.


Subject(s)
Kidney Failure, Chronic/therapy , Oxaliplatin/pharmacokinetics , Oxaliplatin/therapeutic use , Renal Dialysis , Stomach Neoplasms/drug therapy , Antineoplastic Combined Chemotherapy Protocols/pharmacokinetics , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Dose-Response Relationship, Drug , Fluorouracil/pharmacokinetics , Fluorouracil/therapeutic use , Humans , Kidney Failure, Chronic/metabolism , Leucovorin/pharmacokinetics , Leucovorin/therapeutic use , Male , Middle Aged , Organoplatinum Compounds/pharmacokinetics , Organoplatinum Compounds/therapeutic use
6.
Cancer Chemother Pharmacol ; 86(4): 547-558, 2020 10.
Article in English | MEDLINE | ID: mdl-32949265

ABSTRACT

PURPOSE: This prospective, open-label, sequential 'before vs. after' pilot study was conducted to provide preliminary efficacy and tolerability data for ibudilast in the prevention of oxaliplatin-induced neurotoxicity in patients with metastatic upper gastrointestinal or colorectal cancer. Any potential impact of ibudilast on oxaliplatin and 5-fluorouracil pharmacokinetics was also explored. METHODS: Participants were administered a chemotherapy cycle (FOLFOX or CapeOx), followed by a chemotherapy cycle with co-administration of ibudilast 30 mg b.i.d. p.o. Efficacy was assessed on Day 3 and end of cycle using the Oxaliplatin-Specific Neurotoxicity Scale (OSNS) and additional clinical/patient-reported neurotoxicity measures. A population pharmacokinetic approach was used to determine oxaliplatin and 5-fluorouracil pharmacokinetics with and without ibudilast. RESULTS: Sixteen participants consented; 14 completed both chemotherapy cycles. Across all measures, the majority of participants experienced either an improvement or no worsening of neurotoxicity with ibudilast treatment. Based on OSNS assessments, acute neurotoxicity was unchanged in 12/14 participants and improved in 2/14 participants. The 90% confidence interval (CI) of the dose-normalised ratio of oxaliplatin AUC (90% CI 95.0-109%) and 5-fluorouracil AUC (90% CI 66.5-173%) indicated no significant impact of ibudilast on systemic exposure. CONCLUSION: This pilot study indicated ibudilast co-administration may improve or stabilise oxaliplatin-induced neurotoxicity. Given the expected worsening of symptoms in patients with continued chemotherapy, this represents a signal of effect that warrants further investigation. Pharmacokinetic analysis indicates ibudilast has no significant effect on oxaliplatin pharmacokinetics, and is unlikely to influence pharmacokinetics of 5-fluorouracil. CLINICAL TRIAL REGISTRATION: Trial registration number: UTN U1111-1209-0075 and ANZCTRN12618000232235 (registered 13/02/2018).


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/adverse effects , Gastrointestinal Neoplasms/drug therapy , Neurotoxicity Syndromes/prevention & control , Oxaliplatin/adverse effects , Pyridines/administration & dosage , Aged , Antineoplastic Combined Chemotherapy Protocols/pharmacokinetics , Drug Interactions , Female , Fluorouracil/adverse effects , Fluorouracil/pharmacokinetics , Gastrointestinal Neoplasms/blood , Gastrointestinal Neoplasms/pathology , Humans , Leucovorin/adverse effects , Leucovorin/pharmacokinetics , Male , Middle Aged , Neurotoxicity Syndromes/diagnosis , Neurotoxicity Syndromes/etiology , Organoplatinum Compounds/adverse effects , Organoplatinum Compounds/pharmacokinetics , Oxaliplatin/pharmacokinetics , Pilot Projects , Prospective Studies , Pyridines/adverse effects , Pyridines/pharmacokinetics , Severity of Illness Index
7.
J Chemother ; 32(6): 310-322, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32441565

ABSTRACT

We studied the predictive value for response and toxicity of functional polymorphisms in genes involved in the oxaliplatin/fluorouracil pathway in colorectal cancer patients. One hundred and twenty-seven (127) patients were treated with curative intended surgery followed by adjuvant chemotherapy with FOLFOX (fluorouracil, leucovorin and oxaliplatin) regimen. The median age was 65.53 (27-80) years (66.9% male, 59.1% rectum). The median follow-up was 8.5 years (IQR, 4.1-9.4). At the end of follow-up, 59 patients (46.5%) had relapsed or died in the whole study population. We did find that XRCC1GG genotype is associated with a higher risk of developing haematologic toxicity. Furthermore, we report a significant association of the TS 3'UTR 6 bp/6 bp polymorphism and the XRCC1 rs25487 with a higher risk of developing anaemia and diarrhoea, respectively. On the other hand, none of the studied polymorphisms showed clinically relevant association with disease-free survival and overall survival or early failure to adjuvant FOLFOX therapy.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/genetics , Adaptor Proteins, Signal Transducing/genetics , Adaptor Proteins, Signal Transducing/metabolism , Adult , Aged , Aged, 80 and over , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Antineoplastic Combined Chemotherapy Protocols/pharmacokinetics , Chemotherapy, Adjuvant , Colorectal Neoplasms/metabolism , Colorectal Neoplasms/surgery , Cytoskeletal Proteins/genetics , Cytoskeletal Proteins/metabolism , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Endonucleases/genetics , Endonucleases/metabolism , Female , Fluorouracil/administration & dosage , Fluorouracil/adverse effects , Fluorouracil/pharmacokinetics , Humans , Leucovorin/administration & dosage , Leucovorin/adverse effects , Leucovorin/pharmacokinetics , Male , Middle Aged , Neoplasm Staging , Organoplatinum Compounds/administration & dosage , Organoplatinum Compounds/adverse effects , Organoplatinum Compounds/pharmacokinetics , Oxaliplatin/administration & dosage , Oxaliplatin/adverse effects , Oxaliplatin/pharmacokinetics , Polymorphism, Genetic , Promoter Regions, Genetic , Thymidylate Synthase/genetics , Thymidylate Synthase/metabolism
8.
Trials ; 20(1): 751, 2019 Dec 19.
Article in English | MEDLINE | ID: mdl-31856912

ABSTRACT

BACKGROUND: Regorafenib is an oral multikinase inhibitor for metastatic colorectal cancer (mCRC) previously treated with fluoropyrimidines, irinotecan, oxaliplatin, monoclonal antibodies targeting vascular endothelial growth factor, and monoclonal antibodies targeting epidermal growth factor receptor. A dose reduction from 160 mg to 120 mg regorafenib reduces regorafenib-associated adverse events (AEs). Dose adjustment of irinotecan in a 5-fluorouracil/leucovorin/irinotecan (FOLFIRI) regimen on the basis of an individual uridine diphosphate glucuronosyl transferase 1A1 (UGT1A1) genotype provides optimal oncological outcomes with acceptable AEs. The aim of this study is to address the efficacy and safety of a dose-adjusted combination of regorafenib and FOLFIRI for patients with mCRC. METHODS: A prospective, multicenter, randomized in a 2:1 ratio, controlled, clinical trial with two parallel arms will be conducted to compare irinotecan dose-escalated FOLFIRI according to UGT1A1 genotyping plus 120 mg regorafenib with 120 mg regorafenib alone in previously treated patients with mCRC. The primary endpoint is progression-free survival, and the secondary endpoints are overall survival, disease control rate, time to progression, and duration of treatment. Safety assessments will also be recorded. DISCUSSION: Dose adjustment for regorafenib and irinotecan makes treatment-related AEs tolerable and makes the concomitant treatment practicable. This study will provide initial evidence regarding the efficacy and safety of a new combination of chemotherapy and a targeted agent for mCRC. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03880877. Prospectively registered on 19 March 2019.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Camptothecin/analogs & derivatives , Colorectal Neoplasms/drug therapy , Glucuronosyltransferase/genetics , Irinotecan/administration & dosage , Phenylurea Compounds/administration & dosage , Pyridines/administration & dosage , Adult , Aged , Aged, 80 and over , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Antineoplastic Combined Chemotherapy Protocols/pharmacokinetics , Camptothecin/administration & dosage , Camptothecin/adverse effects , Camptothecin/pharmacokinetics , Clinical Trials, Phase II as Topic , Colorectal Neoplasms/genetics , Colorectal Neoplasms/mortality , Disease Progression , Dose-Response Relationship, Drug , Drug Administration Schedule , Female , Fluorouracil/administration & dosage , Fluorouracil/adverse effects , Fluorouracil/pharmacokinetics , Genotyping Techniques , Humans , Irinotecan/adverse effects , Irinotecan/pharmacokinetics , Leucovorin/administration & dosage , Leucovorin/adverse effects , Leucovorin/pharmacokinetics , Male , Middle Aged , Multicenter Studies as Topic , Phenylurea Compounds/adverse effects , Phenylurea Compounds/pharmacokinetics , Precision Medicine/adverse effects , Precision Medicine/methods , Prodrugs/administration & dosage , Prodrugs/adverse effects , Prodrugs/pharmacokinetics , Progression-Free Survival , Pyridines/adverse effects , Pyridines/pharmacokinetics , Randomized Controlled Trials as Topic , Time Factors , Young Adult
9.
Se Pu ; 37(6): 581-588, 2019 Jun 08.
Article in Chinese | MEDLINE | ID: mdl-31152507

ABSTRACT

A simple, sensitive, and stable high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed and validated for the simultaneous determination of leucovorin and 5-methyltetrahydrofolate diastereomers in human plasma using methotrexate as the internal standard. The analytes and the internal standard were extracted from plasma samples by simple ultrafiltration centrifugation-based extraction. The separation was achieved on a chiral HSA column (150 mm×4 mm, 5 µm) using mobile phases containing 10 mmol pH 8.0 ammonium acetate and acetonitrile in gradient mode. The method showed good linearities in the ranges of 25-5000 µg/L and 12.5-3000 µg/L for leucovorin and 5-methyltetrahydrofolate diastereoisomers, respectively. The method was fully validated with respect to sensitivity, precision, accuracy, matrix effect, extraction recovery, and stability of analytes under various conditions. The method was successfully applied to a pharmacokinetic study of 125 mg/m2 6R,S-leucovorin and 62.5 mg/m2 6S-leucovorin. The results showed that the maximum observed concentrations (Cmax) of 6S-leucovorin and L-5-methyltetrahydrofolate were (3137.917±408.837) and (1679.633±244.132) µg/L, respectively, and the areas under the curve from the time of dosing to the last measurable concentration (AUC0-t) were (7504.883±1185.101) and (14001.214±2868.949) µg/L in the 125 mg/m2 6R,S-leucovorin dose group. The Cmax values of 6S-leucovorin and L-5-methyltetrahydrofolate were (3187.917±387.298) and (1739.204±224.755) µg/L, respectively, and AUC0-t values were (7426.664±854.825) and (14884.331±1843.353) µg/L in the 62.5 mg/m2 6S-leucovorin dose group. There were no significant diffe-rences in the main pharmacokinetic parameters between the two dose groups, and the pharmacokinetic characteristics as well as the rate and extent of absorption were consistent. This method can provide technical support for future bioequivalence studies of sodium leucovorin.


Subject(s)
Leucovorin/blood , Tetrahydrofolates/blood , Centrifugation , Chromatography, High Pressure Liquid , Humans , Leucovorin/pharmacokinetics , Reproducibility of Results , Tandem Mass Spectrometry , Tetrahydrofolates/pharmacokinetics , Ultrafiltration
10.
Asia Pac J Clin Oncol ; 15(3): 151-157, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30843362

ABSTRACT

BACKGROUND: 5-Fluorouracil (5-FU) is administered with leucovorin (LV) to enhance clinical activity. However, simultaneous administration is not feasible due to their chemical incompatibility, so conditions for the maximum possible beneficial interaction cannot be met. To overcome this, we developed a novel all-in-one, pH neutral stable solution of 5-FU plus LV with ß-cyclodextrin (termed Deflexifol) and assessed its safety and tolerability in a first-in-human phase I trial. METHODS: Patients with advanced solid malignancy received Deflexifol as weekly bolus (375-575 mg/m²) or two-weekly 46 h infusion (1200-3600 mg/m²) for six cycles in a 3+3 dose escalation design. Adverse events, pharmacokinetics and tumor response rates were assessed by standard methods. RESULTS: Forty patients were treated (19 bolus, 21 infusional, median age 67) with no grade 4 adverse events reported. Dose-limiting toxicities of grade 3 diarrhea and myelosuppression were reported for the bolus schedule at 575 mg/m2 (maximum tolerated dose 525 mg/m²), whereas none were reported for the infusional schedule. The recommended phase II infusional dose was declared as 3,000 mg/m², >25% that of 5-FU used in standard-of-care regimens. Pharmacokinetic analyses showed evidence of inter-patient variability, with no evidence of saturation in clearance, and a trend to linear increase in AUC with dose. Disease control rate was 64% despite most patients having failed previous 5-FU regimens. CONCLUSION: Deflexifol is safer and effective in bolus and infusion schedules at higher doses than that permitted by separate infusion of 5-FU and LV. A phase II study evaluating Deflexifol is planned.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Antineoplastic Combined Chemotherapy Protocols/pharmacokinetics , Neoplasms/drug therapy , Adult , Aged , Female , Fluorouracil/administration & dosage , Fluorouracil/adverse effects , Fluorouracil/pharmacokinetics , Humans , Leucovorin/administration & dosage , Leucovorin/adverse effects , Leucovorin/pharmacokinetics , Male , Maximum Tolerated Dose , Middle Aged
11.
Eur J Clin Pharmacol ; 75(4): 529-542, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30610273

ABSTRACT

PURPOSE: Irinotecan (CPT-11) is a drug used against a wide range of tumor types. The individualized dosing of CPT-11 is essential to ensure optimal pharmacotherapy in cancer patients, given the wide interindividual pharmacokinetic variability of this drug and its active metabolite SN-38. Moreover, the reabsorption from SN-38-G to SN-38, by enterohepatic recirculation, is critical due to its influence in the treatment tolerance. The aim of this research was to build a joint population pharmacokinetic model for CPT-11 and its metabolites (SN-38, and its glucuronide, SN-38-G) that enabled an individualized posology adjustment. METHODS: We used data of 53 treatment cycles of FOLFIRINOX scheme corresponding to 20 patients with metastatic colorectal cancer. In order to build the population pharmacokinetic model, we implemented parametric and non-parametric methods using the Pmetrics library package for R. We also built multivariate regression models to predict the area under the curve and the maximum concentration using basal covariates. RESULTS: The final model was a multicompartmental model which represented the transformations from CPT-11 to its active metabolite SN-38 and from SN-38 to inactive SN-38-G. Besides, the model also represented the extensive elimination of SN-38-G and the reconversion of the remaining SN-38-G to SN-38 by enterohepatic recirculation. We carried out internal validation with 1000 simulations. The regression models predicted the PK parameters with R squared adjusted up to 0.9499. CONCLUSION: CPT-11, SN-38, and SN-38-G can be correctly described by the multicompartmental model presented in this work. As far as we know, it is the first time that a joint model for CPT-11, SN-38, and SN-38-G that includes the process of reconversion from SN-38-G to SN-38 is characterized.


Subject(s)
Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/metabolism , Irinotecan/pharmacokinetics , Models, Biological , Aged , Antineoplastic Agents, Phytogenic/administration & dosage , Antineoplastic Agents, Phytogenic/blood , Antineoplastic Agents, Phytogenic/pharmacokinetics , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/pharmacokinetics , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Camptothecin/analogs & derivatives , Camptothecin/pharmacokinetics , Colorectal Neoplasms/blood , Colorectal Neoplasms/pathology , Female , Fluorouracil/administration & dosage , Fluorouracil/pharmacokinetics , Glucuronates/pharmacokinetics , Humans , Irinotecan/administration & dosage , Irinotecan/blood , Leucovorin/administration & dosage , Leucovorin/pharmacokinetics , Male , Middle Aged , Neoplasm Metastasis , Organoplatinum Compounds/administration & dosage , Organoplatinum Compounds/pharmacokinetics
12.
Cancer Chemother Pharmacol ; 83(1): 27-42, 2019 01.
Article in English | MEDLINE | ID: mdl-30446786

ABSTRACT

PURPOSE: FOLFIRINOX regimen is commonly used in colorectal and more recently pancreatic cancer. However, FOLFIRINOX induces significant and dose-limiting toxic effects leading to empirical dose reduction and sometimes treatment discontinuation. Model-based FOLFIRINOX regimen optimization might help improving patients' outcome. As a first step, the current review aims at bringing together all published population pharmacokinetics models for FOLFIRINOX anticancer drugs. METHODS: A literature search was conducted in the PubMed database from inception to February 2018, using the following terms: population pharmacokinetic(s), irinotecan, oxaliplatin, fluorouracil, FOLFIRI, FOLFOX, FOLFIRINOX. Only articles displaying nonlinear mixed effect models were included. Study description, pharmacokinetic parameter values and influential covariates are reported. For each model, the typical pharmacokinetic profile was simulated for the standard FOLFIRINOX protocol. RESULTS: The FOLFIRINOX compounds have been studied only separately so far. A total of six articles were retained for 5-fluorouracil, 6 for oxaliplatin and 5 for irinotecan (also including metabolites). Either one- or two-compartment models have been described for 5-fluorouracil, while two- or three-compartment models were reported for oxaliplatin and irinotecan pharmacokinetics. Non-linear elimination was sometimes reported for 5-fluorouracil. Sex and body size were found as influential covariates for all molecules in some publications. Despite some differences in model structures and parameter values, the simulated profiles and subsequent exposure were consistent between studies. CONCLUSIONS: The current review allows for a global understanding of FOLFIRINOX pharmacokinetics, and will provide a basis for further development of pharmacokinetics-pharmacodynamics-toxicity models for model-driven FOLFIRINOX protocol optimization to reach the best benefit-to-risk ratio.


Subject(s)
Antineoplastic Agents/pharmacokinetics , Antineoplastic Combined Chemotherapy Protocols/pharmacokinetics , Neoplasms/drug therapy , Antineoplastic Agents/pharmacology , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Clinical Trials as Topic , Fluorouracil/pharmacokinetics , Fluorouracil/pharmacology , Humans , Irinotecan/pharmacokinetics , Irinotecan/pharmacology , Leucovorin/pharmacokinetics , Leucovorin/pharmacology , Neoplasms/metabolism , Oxaliplatin/pharmacokinetics , Oxaliplatin/pharmacology , Tissue Distribution
13.
Br J Cancer ; 118(7): 938-946, 2018 04.
Article in English | MEDLINE | ID: mdl-29527010

ABSTRACT

BACKGROUND: Veliparib is a potent poly(ADP-ribose) polymerase inhibitor. This phase 1 study aimed to establish the maximum tolerated dose (MTD) and recommended phase 2 dose (RP2D) of veliparib combined with various FOLFIRI regimens in patients with solid tumours. METHODS: Patients received veliparib (10-270 mg BID, days 1-5, 15-19) and FOLFIRI (days 1-3, 15-17) in three regimens containing 5-fluorouracil 2,400 mg/m2: irinotecan 150 mg/m2 and folinic acid 400 mg/m2 (part 1); irinotecan 180 mg/m2, folinic acid 400 mg/m2, and 5-fluorouracil 400 mg/m2 bolus (part 2), or irinotecan 180 mg/m2 (part 3). The RP2D was further evaluated in safety expansion cohorts. Preliminary antitumour activity was also assessed. RESULTS: Ninety-two patients received ≥1 veliparib dose. MTD was not reached; RP2D was set at 200 mg BID veliparib plus FOLFIRI (without 5-fluorouracil bolus). Most common treatment-emergent adverse events were neutropenia (66.3%), diarrhoea, and nausea (60.9% each). Dose-limiting toxicities (n = 4) were grade 3 gastritis and grade 4 neutropenia and febrile neutropenia. Veliparib exposure was dose-proportional, with no effects on the pharmacokinetics of FOLFIRI components. Fifteen patients had a partial response (objective response rate, 17.6%). CONCLUSIONS: The acceptable safety profile and preliminary antitumour activity of veliparib plus FOLFIRI support further evaluation of this combination.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Benzimidazoles/administration & dosage , Camptothecin/analogs & derivatives , Neoplasms/drug therapy , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/pharmacokinetics , Benzimidazoles/pharmacokinetics , Camptothecin/administration & dosage , Camptothecin/pharmacokinetics , Disease Progression , Dose-Response Relationship, Drug , Drug Administration Schedule , Female , Fluorouracil/administration & dosage , Fluorouracil/pharmacokinetics , Humans , Leucovorin/administration & dosage , Leucovorin/pharmacokinetics , Male , Middle Aged , Neoplasms/metabolism , Neoplasms/pathology , Treatment Outcome , Young Adult
14.
Cancer Sci ; 108(10): 2045-2051, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28763145

ABSTRACT

A phase II study of S-1 plus leucovorin (LV) given in a 4-week schedule (2 weeks' administration followed by 2 weeks' rest) for patients with untreated metastatic colorectal cancer (mCRC) showed that the combination was effective, but grade 3 toxicities (diarrhea, stomatitis and anorexia) occurred at a relatively high rate. In this phase II study, we evaluated the efficacy and safety of a 2-week schedule of S-1 plus LV. Patients with mCRC received oral S-1 (40-60 mg) and LV (25 mg) twice daily for 1 week, followed by 1 week's rest. Treatment was repeated until disease progression or unacceptable toxicity. The primary endpoint was response rate. The pharmacokinetics of S-1 and LV in Chinese patients were evaluated on day 1 of the first cycle. Seventy-three patients were enrolled in Japan and China. Of 71 eligible patients, the response rate was 53.5%, and the disease control rate was 83.1%. Median progression-free survival and median overall survival were 6.5 and 24.3 months, respectively. The incidences of grade 3 toxicities were diarrhea 8.3%, stomatitis 8.3%, anorexia 2.8% and neutropenia 9.7%. There were no treatment-related deaths. The pharmacokinetics profiles of S-1 plus LV in Chinese patients were similar to those in Japanese patients. This 2-week schedule of S-1 plus LV showed good efficacy and better tolerability than the 4-week schedule. This therapy will be the base regimen for mCRC to be added by other cytotoxic or molecular-targeted drugs. The optimized treatment schedule for S-1 plus LV was 1 week on and 1 week off.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Colorectal Neoplasms/drug therapy , Leucovorin/administration & dosage , Oxonic Acid/administration & dosage , Tegafur/administration & dosage , Adult , Aged , Aged, 80 and over , Anorexia/chemically induced , Anorexia/epidemiology , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , China , Diarrhea/chemically induced , Diarrhea/epidemiology , Drug Administration Schedule , Drug Combinations , Female , Humans , Japan , Leucovorin/adverse effects , Leucovorin/pharmacokinetics , Male , Middle Aged , Neoplasm Metastasis , Neutropenia/chemically induced , Neutropenia/epidemiology , Oxonic Acid/adverse effects , Oxonic Acid/pharmacokinetics , Stomatitis/chemically induced , Stomatitis/epidemiology , Survival Analysis , Tegafur/adverse effects , Tegafur/pharmacokinetics , Treatment Outcome
15.
Invest New Drugs ; 35(4): 463-470, 2017 08.
Article in English | MEDLINE | ID: mdl-28102464

ABSTRACT

Background This study assessed the preliminary safety, pharmacokinetics (PK) and anti-tumor effects of aflibercept in combination with 5-fluorouracil, leucovorin and irinotecan (FOLFIRI) in Chinese patients with previously-treated advanced solid malignancies. Patients and Methods This open-label single-arm Phase I study conducted at two centers in China included adult (≥18 years) patients with metastatic or unresectable solid malignancies who had received ≥1 prior treatment. Patients received aflibercept 4 mg/kg IV on Day 1 followed by FOLFIRI over Days 1 and 2 every 2 weeks, and were assessed for safety, tumor response, PK parameters and immunogenicity. Post-hoc analyses included calculation of progression-free survival (PFS) for patients with colorectal cancer (CRC). Results A total of 20 patients were enrolled. The most common Grade 3/4 adverse events included neutropenia (35%), hypertension (30%), stomatitis (20%) and proteinuria (20%), and no anti-aflibercept antibodies were detected. Six patients achieved a partial response, and in 15 patients with CRC median PFS was 5.95 months (95% CI: 5.29-8.77). Free aflibercept remained in excess of VEGF-bound aflibercept for the majority of the study treatment duration. The mean free aflibercept values for Cmax (64.8 µg/mL) AUC (291 µg.day/mL), CL (0.92 L/day) and Vss (5.9 L) were similar to those measured in Caucasian patients. The addition of aflibercept did not influence the PK of the chemotherapy agents. Conclusion For Chinese patients with pre-treated advanced solid malignancies, 4 mg/kg of aflibercept in combination with FOLFIRI was well-tolerated, demonstrated preliminary anti-tumor activity and had a PK profile consistent with that in Caucasian patients.


Subject(s)
Antineoplastic Agents , Antineoplastic Combined Chemotherapy Protocols , Camptothecin/analogs & derivatives , Neoplasms/drug therapy , Receptors, Vascular Endothelial Growth Factor , Recombinant Fusion Proteins , Adult , Aged , Antineoplastic Agents/adverse effects , Antineoplastic Agents/pharmacokinetics , Antineoplastic Agents/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Antineoplastic Combined Chemotherapy Protocols/pharmacokinetics , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Asian People , Camptothecin/adverse effects , Camptothecin/pharmacokinetics , Camptothecin/therapeutic use , Female , Fluorouracil/adverse effects , Fluorouracil/pharmacokinetics , Fluorouracil/therapeutic use , Humans , Hypertension/chemically induced , Leucovorin/adverse effects , Leucovorin/pharmacokinetics , Leucovorin/therapeutic use , Male , Middle Aged , Neoplasms/blood , Neoplasms/metabolism , Neutropenia/chemically induced , Proteinuria/chemically induced , Receptors, Vascular Endothelial Growth Factor/therapeutic use , Recombinant Fusion Proteins/adverse effects , Recombinant Fusion Proteins/pharmacokinetics , Recombinant Fusion Proteins/therapeutic use , Stomatitis/chemically induced , Treatment Outcome , Vascular Endothelial Growth Factor A/metabolism , White People
16.
Cancer Chemother Pharmacol ; 79(1): 107-116, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27933371

ABSTRACT

PURPOSE: S-1 has shown a response rate of 35% in chemonaïve patients with metastatic colorectal cancer (mCRC). Leucovorin enhances the antitumor activity of 5-fluorouracil, and concurrent oral administration of S-1 and leucovorin may represent a more active treatment option for mCRC. METHODS: S-1 (35 mg/m2) and leucovorin (25 mg/body) were orally administered twice daily to chemonaïve patients with mCRC. Predefined dose (schedule)-limiting toxicities (DLTs) during the first course and treatment continuity during the first two courses were evaluated during three periods of treatment with S-1 plus leucovorin (level 0, 2 weeks; level 1, 3 weeks; and level 2, 4 weeks), each followed by a 2-week rest. The pharmacokinetics (PK) of S-1 and leucovorin were studied on days 1 and 14 of the first course. RESULTS: Fifteen patients were enrolled. All three patients had DLTs at level 2, and this level was considered the maximum tolerated schedule. Level 0 was designated as the recommended schedule based on the incidences of DLTs and treatment continuity. The main toxic effects were gastrointestinal, such as diarrhea and stomatitis. There was no grade 4 adverse event or treatment-related death. The overall response rate was 67% (95% confidence interval, 38-88%). The PK profiles of S-1 plus leucovorin were similar to those in previous studies. CONCLUSIONS: The recommended schedule was 2 weeks of S-1 plus leucovorin followed by a 2-week rest. The increased response and gastrointestinal toxicities of S-1 plus leucovorin as compared with S-1 monotherapy suggest that co-administration of leucovorin enhanced the activity of S-1.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Colorectal Neoplasms/drug therapy , Administration, Oral , Adult , Aged , Drug Combinations , Female , Humans , Leucovorin/administration & dosage , Leucovorin/adverse effects , Leucovorin/pharmacokinetics , Male , Middle Aged , Oxonic Acid/administration & dosage , Oxonic Acid/adverse effects , Oxonic Acid/pharmacokinetics , Tegafur/administration & dosage , Tegafur/adverse effects , Tegafur/pharmacokinetics
17.
BMC Cancer ; 16(1): 907, 2016 11 21.
Article in English | MEDLINE | ID: mdl-27871319

ABSTRACT

BACKGROUND: PEP02 (also known as MM-398, nal-IRI) is a novel nanoparticle formulation of irinotecan encapsulated in liposomes. The aims of this study were to investigate the dose-limiting toxicity (DLT), maximum tolerated dose (MTD) and pharmacokinetics (PK) of PEP02 in combination with 5-FU and LV, in patients with advanced refractory solid tumors. METHODS: Patients were enrolled in cohorts to receive PEP02 from 60 to 120 mg/m2 (dose expressed as the irinotecan hydrochloride trihydrate salt) as a 90-min intravenous infusion on day 1, followed by 24 h infusion of 5-FU 2,000 mg/m2 and LV 200 mg/m2 on days 1 and 8, every 3 weeks. RESULTS: A total of 16 patients were assigned to four dose levels, 60 (three patients), 80 (six patients), 100 (five patients) and 120 mg/m2 (two patients). DLT was observed in four patients, two at the 100 mg/m2 dose level (one had grade III infection with hypotension and grade III hemorrhage; the other had grade III diarrhea and grade IV neutropenia), and two at the 120 mg/m2 dose level (one had grade III diarrhea and grade IV neutropenia; the other had grade III diarrhea). The MTD of PEP02 was determined as 80 mg/m2. The most common treatment-related adverse events were nausea (81%), diarrhea (75%) and vomiting (69%). Among the six patients who received the MTD, one patient exhibited partial response, four patients had stable disease and one showed progressive disease. Pharmacokinetic data showed that PEP02 had a lower peak plasma concentration, longer half-life, and increased area under the plasma concentration-time curve from zero to time t of SN-38 than irinotecan at similar dose level. CONCLUSIONS: The MTD of PEP02 on day 1 in combination with 24-h infusion of 5-FU and LV on days 1 and 8, every 3 weeks was 80 mg/m2, which will be the recommended dose for future studies. TRIAL REGISTRATION: The trial was retrospectively registered ( NCT02884128 ) with date of registration: August 12, 2016.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Neoplasms/drug therapy , Neoplasms/pathology , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Camptothecin/administration & dosage , Camptothecin/analogs & derivatives , Camptothecin/pharmacokinetics , Drug Administration Schedule , Drug Combinations , Drug Monitoring , Female , Fluorouracil/administration & dosage , Fluorouracil/pharmacokinetics , Humans , Leucovorin/administration & dosage , Leucovorin/pharmacokinetics , Liposomes , Male , Middle Aged , Neoplasm Grading , Neoplasm Staging , Neoplasms/genetics , Pharmacogenomic Variants , Sucrose/administration & dosage , Sucrose/analogs & derivatives , Sucrose/pharmacokinetics , Treatment Outcome
18.
Proc Natl Acad Sci U S A ; 113(8): 2200-5, 2016 Feb 23.
Article in English | MEDLINE | ID: mdl-26858448

ABSTRACT

Poor delivery and systemic toxicity of many cytotoxic agents, such as the recent promising combination chemotherapy regimen of folinic acid (leucovorin), fluorouracil, irinotecan, and oxaliplatin (FOLFIRINOX), restrict their full utility in the treatment of pancreatic cancer. Local delivery of chemotherapies has become possible using iontophoretic devices that are implanted directly onto pancreatic tumors. We have fabricated implantable iontophoretic devices and tested the local iontophoretic delivery of FOLFIRINOX for the treatment of pancreatic cancer in an orthotopic patient-derived xenograft model. Iontophoretic delivery of FOLFIRINOX was found to increase tumor exposure by almost an order of magnitude compared with i.v. delivery with substantially lower plasma concentrations. Mice treated for 7 wk with device FOLFIRINOX experienced significantly greater tumor growth inhibition compared with i.v. FOLFIRINOX. A marker of cell proliferation, Ki-67, was stained, showing a significant reduction in tumor cell proliferation. These data capitalize on the unique ability of an implantable iontophoretic device to deliver much higher concentrations of drug to the tumor compared with i.v. delivery. Local iontophoretic delivery of cytotoxic agents should be considered for the treatment of patients with unresectable nonmetastatic disease and for patients with the need for palliation of local symptoms, and may be considered as a neoadjuvant approach to improve resection rates and outcome in patients with localized and locally advanced pancreatic cancer.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Camptothecin/analogs & derivatives , Carcinoma, Pancreatic Ductal/drug therapy , Infusion Pumps, Implantable , Pancreatic Neoplasms/drug therapy , Animals , Antineoplastic Combined Chemotherapy Protocols/pharmacokinetics , Camptothecin/administration & dosage , Camptothecin/pharmacokinetics , Carcinoma, Pancreatic Ductal/metabolism , Carcinoma, Pancreatic Ductal/pathology , Cell Proliferation/drug effects , Fluorouracil/administration & dosage , Fluorouracil/pharmacokinetics , Humans , Iontophoresis/instrumentation , Leucovorin/administration & dosage , Leucovorin/pharmacokinetics , Mice , Mice, Nude , Organoplatinum Compounds/administration & dosage , Organoplatinum Compounds/pharmacokinetics , Pancreatic Neoplasms/metabolism , Pancreatic Neoplasms/pathology , Xenograft Model Antitumor Assays
19.
Br J Cancer ; 112(12): 1874-81, 2015 Jun 09.
Article in English | MEDLINE | ID: mdl-25989270

ABSTRACT

BACKGROUND: The mitogen-activated protein kinase (MAPK) pathway has been implicated in the molecular pathogenesis of human cancers, including metastatic colorectal cancer (mCRC). This provides a rationale for the development of MAPK-targeted agents such as pimasertib. METHODS: Patients with KRAS mutant mCRC were treated in the second-line setting with FOLFIRI (5-fluorouracil/folinic acid/irinotecan) plus pimasertib. The primary objective of the safety run-in phase was to determine the maximum-tolerated dose (MTD) and the recommended phase II dose of pimasertib combined with FOLFIRI. RESULTS: Sixteen patients were enrolled in the trial. Ten and six patients were treated daily with 45 and 60 mg of pimasertib plus FOLFIRI, respectively. The MTD was considered to be 45 mg per day. The most common treatment-emergent adverse events were diarrhoea, nausea, vomiting, asthenia and skin/rash event. Of the 15 patients in the efficacy analysis group, two patients had partial response, nine patients had stable disease, three patients had progressive disease as their best overall response and one patient could not be evaluated. CONCLUSIONS: Dose escalation of pimasertib in combination with FOLFIRI was limited by toxicity. At the MTD of 45 mg per day, pimasertib was adequately tolerated in patients with mCRC and no unexpected or new safety signals or concerns were identified.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Colorectal Neoplasms/drug therapy , Aged , Aged, 80 and over , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/pharmacokinetics , Camptothecin/administration & dosage , Camptothecin/analogs & derivatives , Camptothecin/pharmacokinetics , Colorectal Neoplasms/enzymology , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Female , Fluorouracil/administration & dosage , Fluorouracil/pharmacokinetics , Genes, ras , Humans , Leucovorin/administration & dosage , Leucovorin/pharmacokinetics , Male , Middle Aged , Mutation , Neoplasm Metastasis , Niacinamide/administration & dosage , Niacinamide/analogs & derivatives , Niacinamide/pharmacokinetics , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins p21(ras) , Treatment Outcome , ras Proteins/genetics
20.
Am J Clin Nutr ; 100(5): 1278-86, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25332326

ABSTRACT

BACKGROUND: Folate intakes that do not meet or greatly exceed requirements may be associated with negative health outcomes. A better understanding of contributors that influence the input side will help establish dietary guidance that ensures health benefits without associated risks. Colonic microbiota produce large quantities of folate, and [(13)C5]5-formyltetrahydrofolate infused during colonoscopy is absorbed. However, it is unclear if significant quantities of folate are absorbed in an intact microbiome. OBJECTIVE: We determined whether and how much of a physiologic dose of [(13)C5]5-formyltetrahydrofolate delivered in a pH-sensitive enteric caplet to an intact colonic microbiome is absorbed. DESIGN: Healthy adults ingested a specially designed pH-sensitive acrylic copolymer-coated barium sulfate caplet that contained 855 nmol (400 µg) [(13)C5]5-formyltetrahydrofolate. After a washout period ≥ 4 wk, subjects received an intravenous injection of the same compound (214 nmol). Serially collected blood samples before and after each test dose were analyzed by using a microbiological assay and liquid chromatography-tandem mass spectrometry. RESULTS: Caplet disintegration in the colon was observed by fluoroscopic imaging for 6 subjects with a mean (± SD) complete disintegration time of 284 ± 155 min. The mean (± SEM) rate of appearance of [(13)C5]5-methyltetrahydrofolate in plasma was 0.33 ± 0.09 (caplet) and 5.8 ± 1.2 (intravenous) nmol/h. Likely because of the significant time in the colon, the mean apparent absorption across the colon was 46%. CONCLUSIONS: Folate is absorbed across the colon in humans with an undisturbed microbiome. This finding and previous observations of the size of the colonic depot of folate and its potential for manipulation by diet (eg, dietary fiber, oligosaccharides, and probiotics) suggest that an individual's dietary folate requirement may differ depending on the consumption of dietary constituents that affect the size and composition of their gastrointestinal microbiota. In addition, a systematic investigation of the role of colonic folate on gastrointestinal development and the prevention of colorectal cancer is warranted. This trial was registered at clinicaltrials.gov as NCT00941174.


Subject(s)
Colon/metabolism , Leucovorin/pharmacokinetics , Adolescent , Adult , Aged , Carbon Isotopes , Chromatography, Liquid , Diet , Dose-Response Relationship, Drug , Drug Compounding , Female , Healthy Volunteers , Humans , Hydrogen-Ion Concentration , Leucovorin/administration & dosage , Leucovorin/blood , Male , Middle Aged , Tandem Mass Spectrometry , Young Adult
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