Yvonne Lassere

University of Texas MD Anderson Cancer Center, Houston, Texas, United States

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Publications (22)139.67 Total impact

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    ABSTRACT: The nucleoside 3'-c-ethynylcytidine (TAS-106) was designed to inhibit RNA synthesis which occurs throughout the cell cycle except for the M phase. TAS-106 is incorporated into cells, is rapidly phosphorylated to a monophosphate form, and is preferentially distributed into malignant cells. Preclinical studies showed that TAS-106 has a wide antitumor spectrum against human cancer xenografts. This phase I study was conducted in order to determine the recommended phase II dose of TAS-106 administered once per week for three consecutive weeks, every 28 days in patients with solid tumors. Patients were enrolled in cohorts of three, starting at 0.22 mg/m(2)/dose. Patients received at least two doses in order to be evaluable in each dose cohort. Dose escalation was stopped if two or more patients experienced dose limiting toxicity at any dose level. In 20 evaluable patients, TAS-106 was given at the following dose levels (mg/m(2)/dose): 0.22 (3 pts), 0.33 (3 pts), 0.66 (3 pts), 0.99 (1 pt), 1.32 (3 pts), 2.64 (3 pts) and 3.96 (1 pt). Three additional patients were evaluated at 2.64 mg/m(2)/dose for further characterization of toxicity and safety. A total of 16 patients completed courses 1 and 2. All 21 patients enrolled experienced at least one adverse event. The AE attributed to the study drug was grade 2 peripheral neuropathy characterized by peripheral sensory neuropathy, numbness, tremor, pain, and hyperesthesia involving the fingers, hands, toes, and feet. Due to neurotoxicity the MTD was the 2.64 mg/m(2)/dose for the study schedule. No suggested phase II dose was determined. However, at the 1.32 mg/m(2)/dose level, no patients experienced DLTs during course 1 or 2. This could be further studied to determine its viability as a potential phase II dosage.
    Anticancer research 05/2012; 32(5):1689-96. · 1.87 Impact Factor
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    ABSTRACT: TAS-106 is a novel nucleoside analog that inhibits RNA polymerases I, II and II and has demonstrated robust antitumor activity in a wide range of models of human cancer in preclinical studies. This study was performed to principally evaluate the feasibility of administering TAS-106 as a bolus intravenous (IV) infusion every 3 weeks. Patients with advanced solid malignancies were treated with escalating doses of TAS-106 as a single bolus IV infusion every 3 weeks. Plasma and urine sampling were performed during the first course to characterize the pharmacokinetic profile of TAS-106 and assess pharmacodynamic relationships. Thirty patients were treated with 66 courses of TAS-106 at eight dose levels ranging from 0.67-9.46 mg/m(2). A cumulative sensory peripheral neuropathy was the principal dose-limiting toxicity (DLT) of TAS-106 at the 6.31 mg/m(2) dose level, which was determined to be the maximum tolerated dose (MTD). Other mild-moderate drug-related toxicities include asthenia, anorexia, nausea, vomiting, myelosuppression, and dermatologic effects. Major objective antitumor responses were not observed. The pharmacokinetics of TAS-106 were dose-proportional. The terminal elimination half-life (t(1/2)) averaged 11.3 ± 3.3 h. Approximately 71% of TAS-106 was excreted in the urine as unchanged drug. Pharmacodynamic relationships were observed between neuropathy and: C(5min;) AUC(0-inf;) and dermatologic toxicity. The recommended phase II dose of TAS-106 is 4.21 mg/m(2). However, due to a cumulative drug-related peripheral sensory neuropathy that proved to be dose-limiting, further evaluation of this bolus every 21 day infusion schedule will not be pursued and instead, an alternate dosing schedule of TAS-106 administered as a continuous 24-hour infusion will be explored to decrease C(max) in efforts to minimize peripheral neuropathy and maximize antitumor activity.
    Investigational New Drugs 02/2012; 30(1):316-26. DOI:10.1007/s10637-010-9535-y · 2.93 Impact Factor
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    ABSTRACT: Prolonged infusions have been shown to be safer and potentially more effective than bolus regimens of 5-fluorouracil (5-FU) as treatment for metastatic colorectal cancer (mCRC). However, infusional 5-FU requires central venous access and costly infusion pumps. Oral fluoropyrimidines enable longer exposures to 5-FU with increased convenience. Tegafur-uracil (UFT) with leucovorin (LV) given thrice daily has improved safety plus comparable survival and response rates to bolus 5-FU/LV. We conducted a phase II clinical study in 98 patients with mCRC to evaluate if UFT with LV given twice daily provided comparable time to progression (TTP), efficacy and tolerability to that reported for thrice daily in two phase III clinical studies. Secondary objectives included overall response rate (ORR) and overall survival (OS). Median TTP was 3.8 months, when compared with 3.5 months for thrice daily. The ORR (11%) and median OS (12.8 months) with twice daily administration were similar to that of thrice daily administration (12% and 12.4 months). The incidence of grade 3/4 treatment-related diarrhoea was 30% on the twice daily and 21% on the thrice daily schedule. These results suggest that twice daily administration has similar efficacy and tolerability to thrice daily administration and is an acceptable alternative for patients who would benefit from UFT with LV therapy.
    British Journal of Cancer 10/2008; 99(5):722-6. DOI:10.1038/sj.bjc.6604541 · 4.82 Impact Factor
  • Rita Wickham, Yvonne Lassere
    Seminars in Oncology Nursing 02/2007; 23:1-8. DOI:10.1016/j.soncn.2006.08.001
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    Seminars in Oncology Nursing 02/2007; 23:36-43. DOI:10.1016/j.soncn.2006.08.004
  • EJC Supplements 11/2006; 4(12):185-186. DOI:10.1016/S1359-6349(06)70620-6 · 9.39 Impact Factor
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    ABSTRACT: The purpose of the current study was to determine the maximum tolerated dose, dose-limiting toxicities, pharmacokinetic profile, and recommended Phase II dose of oral administration of TAS-102, a novel nucleoside formed by the combination of alpha,alpha,alpha-trifluorothymidine (FTD) and a thymidine phosphorylase inhibitor (TPI: 5-chloro-6-(2-iminopyrrolidin-1-yl)methyl-2,4(1H,3H)-pyrimidinedione). Eligible patients had advanced solid tumors, adequate organ function, and had not received anticancer therapy in the preceding 4 weeks. TAS-102 was administered orally once daily for 14 days, followed by a 1-week rest, repeated every 3 weeks. The initial dose of TAS-102 administered was 100 mg/m2/day. The first 2 patients treated at that dose experienced substantial toxicity and, therefore, lower dose levels of TAS-102 were subsequently explored. Fourteen patients were enrolled; all patients were evaluable for toxicity assessment and 12 were evaluable for response. The initial dose explored was 100 mg/m2/day, based on a preclinical monkey model. However, the first 2 patients experienced bone marrow suppression of Grade 3 or 4 in course 1. The protocol was amended to study the next cohort of patients at 50 mg/m2/day. At this dose level no Grade 3 or 4 toxicities were observed in course 1. In the subsequent dose level (60 mg/m2/day), 3 of 6 patients experienced Grade 3 or 4 granulocytopenia as dose-limiting toxicity. Three additional patients for a total of 6 were enrolled at 50 mg/m2/day without occurrence of dose-limiting toxicity. Thus, 50 mg/m2/day was declared the maximum tolerated dose for this schedule. The authors' study showed that 50 mg/m2/day was a tolerable dose of the novel antimetabolite FTD in combination with an inhibitor of its inactivating enzyme TP, and this is the recommended Phase II dose. Evaluation of this daily dose in malignancies for which fluoropyrimidines have failed is needed.
    Cancer 09/2006; 107(6):1383-90. DOI:10.1002/cncr.22125 · 4.90 Impact Factor
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    ABSTRACT: Both irinotecan and oxaliplatin are active agents in the treatment of patients with metastatic colorectal cancer (MCC). There is a strong preclinical rationale for combining these two agents. We sought to determine the dose-limiting toxicity (DLT) and the maximum tolerated dose (MTD) of combined irinotecan and oxaliplatin given every three weeks. Cohorts of patients with MCC previously treated with 5-fluorouracil received escalating doses of irinotecan (150, 175, and 200 mg/m(2)) and a fixed dose of oxaliplatin (130 mg/m(2)), both given intravenously every 3 weeks. DLT was evaluated within the first course of treatment. Objective responses were evaluated every two courses and were confirmed at least four weeks later. Fourteen patients were treated and evaluated for toxicity. The DLT was neutropenia, with or without fever, and delayed recovery of neutrophil counts was frequent (13 courses in six patients). Other toxic effects (peripheral neuropathy, nausea, vomiting, diarrhea, and fatigue) were mild to moderate. Among 13 patients evaluable for activity, four achieved partial responses and nine had stable disease. The combination of irinotecan and oxaliplatin is safe and apparently active in the treatment of MCC patients. The recommended dose for phase II studies is 175 mg/m(2) irinotecan plus 130 mg/m(2) oxaliplatin, given every 3 weeks. Neutropenia and delayed recovery of neutrophil counts are the predominant early toxicities with this schedule.
    Investigational New Drugs 09/2004; 22(3):307-13. DOI:10.1023/B:DRUG.0000026257.31142.41 · 2.93 Impact Factor
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    ABSTRACT: Capecitabine is an oral fluoropyrimidine converted to fluourouracil (FU) preferentially in tumor tissue. It has proven clinical activity against colorectal cancer when used as first-line therapy. The objectives of this study were to assess the safety and efficacy of capecitabine in patients with metastatic colorectal carcinoma who progressed despite previous FU therapy. According to the group sequential analysis design of this study, accrual would stop if no responses were observed in the first 20 patients treated. If one or more objective responses were confirmed, the trial would be expanded. Patients received capecitabine 1,250 mg/m(2) twice a day for 14 days, every 3 weeks. Tumor lesions were assessed every 6 weeks, and patients were followed for survival every 3 months after completing treatment. Twenty-three patients were enrolled onto the study; 22 fulfilled all the eligibility criteria. No objective responses were observed among the 22 eligible patients; 11 patients (50%) had stable disease for a median duration of 141 days (range, 88-289 days). The Kaplan-Meier estimate of median time to disease progression was 64 days (95% CI, 41 to 134 days). The median survival time estimate was 389 days (95% CI, 267 to 637 days). The most frequent treatment-related adverse events were hand-foot syndrome, diarrhea, and nausea or vomiting. There were no grade 4 toxicities and no treatment-related deaths. Single-agent capecitabine in patients with metastatic colorectal carcinoma refractory to FU showed no objective responses and clinical benefit that was, at best, modest. The use of capecitabine in combination with other treatments in this patient population is under investigation.
    Journal of Clinical Oncology 07/2004; 22(11):2078-83. DOI:10.1200/JCO.2004.05.072 · 17.88 Impact Factor
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    Yvonne Lassere, Paulo Hoff
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    ABSTRACT: Comparative trials of capecitabine (Xeloda) versus 5-FU/LV in metastatic colorectal cancer have shown that hand-foot syndrome (HFS) was the only clinical adverse event occurring more frequently with capecitabine. Most patients with HFS present with dysesthesia, usually with a tingling sensation in the palms and soles of the hands and feet. This can progress in 3-4 days to burning pain plus well-defined symmetric swelling and erythema. The hands tend to be more commonly affected than the feet, and might even be the only area affected in some patients. HFS can interfere with the general activities of daily living, especially when blistering, moist desquamation, severe pain or ulceration occurs. While HFS is manageable, if ignored it can progress rapidly. However, dose interruption and reduction of capecitabine usually leads to a rapid reversal of signs and symptoms without long-term consequences. Nurses play a key role in educating patients how to recognise HFS, when to interrupt treatment and how to adjust the dose to maintain effective therapy with capecitabine over the long term. It is particularly important that patients and nurses are aware that dose interruption/reduction does not affect the overall antitumour efficacy of capecitabine.
    European Journal of Oncology Nursing 02/2004; 8 Suppl 1:S31-40. DOI:10.1016/j.ejon.2004.06.007 · 1.79 Impact Factor
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    ABSTRACT: Our purpose in the study was to determine the maximum tolerated dose and dose-limiting toxicity and investigate the clinical pharmacology of S-1, a combination of tegafur, 5-chloro-2,4-dihydroxypyridine (CDHP), and potassium oxonate. Eligible patients had advanced solid tumors, adequate organ function, and no anticancer therapy in the preceding 4 weeks. Dose level 1 was 30 mg/m(2)/dose, level 2 was 40 mg/m(2)/dose, and level 3 was 35 allmg/m(2)/dose, all of the levels comprising two daily doses. S-1 was administered as a single dose at each level, and its pharmacology was studied. The first course was begun 3 days later and consisted of 28 consecutive treatment days, followed by a 1-week rest. Sixteen patients were enrolled; toxicity could be assessed in all of the 16 and response in 15. At dose level 1, two of nine patients developed grade 3 hyperbilirubinemia or diarrhea. Dose-limiting toxicity (diarrhea) occurred in all three of the patients at dose level 2. The protocol was, therefore, amended to include an intermediate dose level (level 3), which caused grade 3 or 4 diarrhea or hyperbilirubinemia in three of four patients. Dose level 1 was thus considered as the maximum tolerated dose. Other grade 3 or 4 toxic effects at dose level 2 or 3 were granulocytopenia, nausea, and vomiting. The pharmacology of tegafur, CDHP, potassium oxonate, and fluorouracil (a metabolite of tegafur) was characterized by rapid absorption and was consistent with first-order kinetics. One patient with colorectal cancer had a durable partial response. The recommended S-1 dose for future studies is 30 mg/m(2) twice daily, and diarrhea is the most frequent toxic effect. Additional trials of S-1 in the treatment of patients with solid tumors are warranted.
    Clinical Cancer Research 02/2003; 9(1):134-42. · 8.19 Impact Factor
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    ABSTRACT: To determine the maximum-tolerated dose (MTD), dose-limiting toxicity (DLT), pharmacokinetic (PK) profile, and recommended phase II dose of Exatecan mesylate (DX-8951f) when administered as a 24-hour continuous infusion every 3 weeks to patients with solid tumors. Twenty-two patients with advanced solid tumors, all previously treated, and with performance status < or = 2, were entered. The starting dose of DX-8951f was 0.15 mg/m(2); the dose was escalated according to the modified continual reassessment method. The drug was administered until disease progression or until unacceptable toxic effects occurred. Seven dose escalations were completed, and a total of 53 courses were delivered (median, two courses; range, one to eight courses) during the study. At doses 1.2 mg/m(2) and lower, toxicities were mostly grade 1, primarily hematologic. In the initial cohort of three patients treated at 2.4 mg/m(2), grade 2 hematologic toxicity was observed. Of the six additional patients entered at 2.4 mg/m(2), three had grade 3 or 4 granulocytopenia. At doses higher than 2.4 mg/m(2), DLT granulocytopenia was observed. Nonhematologic toxicities, including nausea, vomiting, diarrhea, fatigue, and alopecia, were mild to moderate. Neither complete nor partial responses were observed, but four patients had stable disease. The PK profile of DX-8951f seemed linear at the doses administered. The plasma clearance, total volume of distribution, and terminal elimination half-life were approximately 3 L/h, 40 L, and 14 hours, respectively. The DLT of this DX-8951f schedule was granulocytopenia for minimally pretreated patients, and both granulocytopenia and thrombocytopenia for heavily pretreated patients. The MTD for both minimally and heavily pretreated patients was 2.4 mg/m(2). DX-8951f seems to have a linear PK profile on the basis of single-dose administration. The recommended phase II dose with this schedule is 2.4 mg/m(2) for minimally pretreated patients. A lower dose should be used for heavily pretreated patients.
    Journal of Clinical Oncology 04/2001; 19(5):1493-500. · 17.88 Impact Factor
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    ABSTRACT: Preoperative combined-modality therapy for rectal cancer may allow for sphincter preservation, while decreasing recurrence rates and improving the overall prognosis. Oral chemotherapy with uracil and tegafur (UFT) plus leucovorin (LV) may reduce costs and complications associated with protracted infusions of fluorouracil. Our goal was to evaluate the safety of UFT plus LV combined with preoperative radiation and determine the maximum-tolerated dose (MTD) and dose-limiting toxicity (DLT) of UFT plus LV in this setting. Patients with tumor-node-metastasis stage II or III rectal cancer received escalating doses of UFT (starting at 250mg/m(2)/d, with 50-mg/m(2)/d increments between consecutive cohorts) and fixed doses of LV (90 mg/d). The UFT and LV combination was given 5 days per week concurrently with a 5-week course of preoperative radiation totaling 45 Gy (1.8 Gy/fraction). Surgery was performed 4 to 6 weeks after radiation and was followed by four 35-day cycles of fixed doses of UFT and LV (28 days of therapy each cycle). Fifteen patients were treated, and 13 received the full preoperative chemotherapy. All planned radiation was delivered successfully. The MTD of UFT with radiation was 350 mg/m(2)/d with 90 mg/d of LV. Diarrhea was the DLT. Sphincter-preserving surgery was performed in 12 of 14 patients. One patient had progressive disease before surgery. Pathologic evaluation of 14 resected specimens showed a complete response in three cases. Preoperative chemoradiation with oral UFT plus LV is feasible and well tolerated and should be further investigated.
    Journal of Clinical Oncology 11/2000; 18(20):3529-34. · 17.88 Impact Factor
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    ABSTRACT: To assess the pharmacokinetics of Ftorafur (tegafur, FT), 5-fluorouracil (5-FU), and uracil in 31 cancer patients who were enrolled in phase I studies of oral uracil and FT (UFT). The correlation between pharmacokinetic parameters and toxic effects of UFT was evaluated. Uracil and FT were orally administered in a 4:1 molar ratio at FT doses of 200-400 mg/m2 per day. Patients also received leucovorin at 150 mg/day. Daily doses were divided into three doses and administered at 8-h intervals for 28 consecutive days. Plasma FT concentrations were measured by high-performance liquid chromatography, and plasma 5-FU and uracil concentrations were determined using gas chromatography-mass spectrometry. National Institutes of Health Common Toxicity Criteria were used for assessment of toxicity. The concentrations of FT, 5-FU, and uracil showed wide interpatient variations. Maximum plasma concentrations (Cp(max)) of all three compounds were achieved in 0.3 to 4.0 h. At the various study doses, the terminal half-life (t 1/2beta) of FT ranged from 3.9 to 5.9 h, the area under the concentration-versus-time curve (AUC0-6h) ranged from 16,220 to 52,446 (ng/ml)h, the total clearance (ClT) ranged from 100 to 175 ml/min, and the steady-state volume of distribution (Vd(ss)) ranged from 18.3 to 28.7 l. The 5-FU generated from FT had an apparent distribution half-life (t 1/2alpha) and an apparent elimination half-life (t 1/2beta) of 0.3-1.3 h and 4.9-7.0 h, respectively. The AUC0-6h of 5-FU ranged from 120 to 325 (ng/ml)h. Uracil had a t 1/2alpha of 0.2-0.5 h and the level quickly returned to the endogenous level. The AUC0-6h for uracil ranged from 605 to 3764 (ng/ml)h, the ClT ranged from 3225 to 7748 ml/min, and the Vd(ss) ranged from 341 to 1354 l. The Cp(max) and AUC0-6h of both FT and uracil were significantly correlated with FT doses (P-values of 0.0244 and 0.0112) and with uracil doses (P-values of 0.0346 and 0.0083), respectively. In addition to interpatient variations, intrapatient variations were also observed in six patients who had pharmacology studies done on days 1 and 26+/-2 at the same study dose. We found that the repeated treatment with UFT caused cumulative increases in the values of Cp(max), Ctrough, and AUC0-6h of FT and 5-FU. The major toxic effects observed were diarrhea and nausea and vomiting. The occurrence of these toxic effects correlated significantly with the Cp(max) and AUC0-6h of 5-FU. The pharmacology studies showed that FT and uracil were readily absorbed orally and that FT was rapidly converted to 5-FU. The preliminary findings suggest that determination of plasma levels of 5-FU after oral administration of UFT may help predict subsequent toxic effects.
    Cancer Chemotherapy and Pharmacology 02/2000; 46(5):351-6. DOI:10.1007/s002800000156 · 2.57 Impact Factor
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    ABSTRACT: Protracted infusions of 5-fluorouracil (5-FU) combined with pelvic radiotherapy have been associated with improved survival and decreased local and distant metastases in the adjuvant therapy of rectal cancer. However, this method of 5-FU infusion requires the inconvenience and expense of central venous line placement and care, infusion pumps, and treatment of catheter-related complications. We previously demonstrated that a completely oral therapy with UFT (uracil plus tegafur in a 4:1 molar ratio) plus oral calcium folinate (Orzel) can achieve pharmacokinetic parameters similar to those associated with protracted 5-FU infusions. This trial examines the feasibility of using UFT plus oral calcium folinate both during preoperative pelvic radiation and postoperatively, and shows that patients can be treated safely and effectively with a completely oral chemotherapy program combining UFT plus oral calcium folinate with pelvic radiation therapy.
    Oncology (Williston Park, N.Y.) 08/1999; 13(7 Suppl 3):129-31. · 2.98 Impact Factor
  • P M Hoff, Y Lassere, R Pazdur
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    ABSTRACT: The oral chemotherapeutic agent tegafur/uracil (UFT) is the first of a new class of anticancer drugs called dihydropyrimidine dehydrogenase inhibitory fluoropyrimidines. Tegafur/uracil combines uracil with the fluorouracil prodrug tegafur in a 4:1 molar ratio. Uracil competitively inhibits the degradation of fluorouracil, which results in the concentration of fluorouracil remaining at sustained levels in both plasma and tumour. Tegafur/uracil has been commercially available in Japan since 1983 and examined extensively in various tumours. Trials conducted in the US have focused on the combination of tegafur/uracil plus calcium folinate (calcium leucovorin) [ORZEL]. Several phase I and II trials have evaluated the maximum tolerated dose, pharmacokinetics, efficacy, and safety of this combination in the treatment of colorectal cancer. Results have shown that tegafur/uracil at 300 mg/m2/day in divided doses given every 8 hours for 28 days provides prolonged exposure to fluorouracil. Furthermore, tegafur/uracil + calcium folinate is well tolerated, with dose-limiting toxicity manifesting as diarrhoea. Compared with intravenous fluorouracil plus folinic acid (leucovorin) regimens, tegafur/uracil + calcium folinate has similar efficacy with less toxicity and is more convenient because it is an oral regimen. Early studies have also shown potential cost savings because of fewer complications.
    Drugs 02/1999; 58 Suppl 3:77-83. DOI:10.2165/00003495-199958003-00011 · 4.13 Impact Factor
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    ABSTRACT: Plasma 5-fluorouracil (5-FU) levels were compared in the same patients after approximately equimolar doses (1.9 mmol/ m2/day) of 5-day continuous i.v. infusion of 5-FU (CIFU) and oral administration of a formulation of two combined pharmacological agents, uracil (U) plus N1-(2'-tetrahydrofuryl)-5-fluorouracil (ftorafur or FT), a prodrug of 5-FU. Ten patients received CIFU for 5 days, then, after a week wash-out period, began the 28-day oral UFT regimen, which was given in three daily divided doses. Following 1 h of CIFU, the plasma 5-FU levels reached a steady state of 0.6+/-0.2 microM (mean+/-SD; day 1), which was maintained for the entire 5-day infusion period (0.6+/-0.1 microM). In contrast, the maximum 5-FU concentrations (Cpmax) generated from oral UFT at 1 h after dose administration on days 1 and 5 were 2.1+/-1.5 microM and 2.3+/-1.9 microM, respectively, which were higher than the steady-state levels during CIFU. These high 5-FU levels disappeared with an apparent elimination half-life (tl/2,beta) of 5.2+/-2.4 h (day 1) and 7.2+/-3.9 h (day 5). On day 1 of both regimens, CIFU patients had significantly larger 5-FU area under the concentration versus time curve (AUC0-8h) values (4.4+/-1.3 microM.h) than the AUC value when they received the UFT regimen (2.6+/-1.7 microM.h; P = 0.02). However, by day 5, there were no significant differences between AUC0-8 h values in patients receiving CIFU and UFT, respectively (4.8+/-1.5 microM.h versus 3.8+/-2.2 microM.h; P = 0.30)]. On day 5, the average concentration of the metabolite 5-FU at steady-state (Css,aver) within dose interval of 8 h (0.48+/-0.28 microM) for the oral UFT treatment is comparable with the Cpss values of 5-FU from CIFU-treated patients. The post-UFT generated 5-FU pharmacokinetic parameters (higher Cp(mx, comparable Css,aver, equal AUC values, and longer apparent t1/2,beta of 5-FU) may make oral UFT a preferred method of delivering this fluoropyrimidine over CIFU. In addition, oral UFT would eliminate the incidence of venous thrombosis and catheter-related infections sometimes seen in patients treated with CIFU. Furthermore, the convenience and decreased cost of oral administration may be preferable for many patients, particularly those receiving 5-FU for palliation.
    Clinical Cancer Research 10/1998; 4(9):2085-8. · 8.19 Impact Factor
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    ABSTRACT: UFT [Taiho Pharmaceutical Co. Ltd., Tokyo, Japan; (BMS-200604), Bristol-Myers Squibb, Princeton, NJ], a fluorouracil prodrug, is an oral 4:1 molar concentration of uracil plus tegafur. This study examined the dose-limiting toxic effects and maximum tolerated dose of UFT plus leucovorin administered for 28 consecutive days followed by a 7-day rest period. A course of therapy was repeated every 35 days. UFT dose levels examined were 200 mg/m2/day, with planned escalations to 250, 300, 350, and 400 mg/m2/day; the leucovorin dose remained at 150 mg/day. Three patients were initially enrolled at each UFT dose level. The total daily doses of both UFT and leucovorin were divided into three doses administered every 8 hr. Diarrhea became the dose-limiting toxicity at 400 mg/m2/day UFT, with grade 3 diarrhea noted in 2 of the 3 patients receiving that dose. To further define a phase II UFT starting dose, 3 additional patients were entered at the 350 mg/m2 level; 3 of the 6 patients treated at this level developed grade 3 nonhematological toxic effects. No partial or complete responses were observed. The recommended phase II UFT starting dose is 300 mg/m2/day plus 150 mg/day leucovorin. Since neutropenia, significant mucositis, and "hand-foot syndrome" were not observed with UFT plus leucovorin, the toxicity profile of this regimen appears favorable compared with that of intravenous regimens of fluorouracil plus leucovorin. This phase I trial of UFT served as the basis for a phase II trial, current phase III trials, and a national adjuvant therapy trial of UFT for high-risk colon cancer patients.
    Cancer Investigation 01/1998; 16(3):145-51. DOI:10.3109/07357909809050028 · 2.06 Impact Factor
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    ABSTRACT: We previously reported results of a Phase II trial of UFT [Taiho Pharmaceutical Ltd., Tokyo, Japan; (BMS-200604) Bristol-Myers Squibb, Princeton, NJ], an oral 4:1 molar concentration of uracil and tegafur, plus oral leucovorin for metastatic colorectal carcinoma (Pazdur et al., J. Clin. Oncol. 12:2296-2300, 1994]. Our results demonstrated that a 28-day schedule of this combination produced a response rate similar to that obtained with conventional intravenous fluorouracil (5-FU)-plus-leucovorin regimens but without the severe or life-threatening neutropenia or oral mucositis that complicates intravenous 5-FU regimens. The current Phase I trial examines the dose-limiting toxic effects and maximum tolerated dose of a 14-consecutive-day schedule of UFT plus oral leucovorin in 14 patients who had histologically proven cancer and had received prior chemotherapy. The daily UFT plus leucovorin dose was divided into three doses administered orally every 8 hours. In this study, the UFT dose was escalated while the leucovorin dose remained at 150 mg/day. Of the 14 patients, 4 were initially treated at the 350-mg/m2/day UFT level for 14 days without any dose-limiting toxic reactions. Subsequently, another 7 patients were treated at the 400-mg/m2/day level; grade 3 diarrhea developed in 3 of these 7 (with severe abdominal cramping in 2 cases and severe nausea and vomiting unresponsive to antiemetics in the third). To better define the starting dose for phase II studies, an additional 3 patients were treated at the 350-mg/m2/day dose level. Of the total 7 patients treated at 350 mg/m2/day, grade 3 toxic events (diarrhea) developed in 2 patients. Grade 1-2 toxic effects noted at this level included fatigue, stomatitis, skin rash, abdominal pain, nausea, and vomiting. Neither partial nor complete responses were observed in this trial. The maximum tolerated dose of this schedule is 350 mg/m2/day UFT plus 150 mg/day oral leucovorin. However, because of this schedule's inferior dose intensity compared with that of the 28-day schedule of UFT plus leucovorin, subsequent development of UFT in the United States has focused on the 28-day regimen.
    Investigational New Drugs 02/1997; 15(2):123-8. DOI:10.1023/A:1005808822565 · 2.93 Impact Factor
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    ABSTRACT: We conducted two consecutive phase I clinical trials to identify the qualitative and quantitative toxic effects of uracil-tegafur (UFT) [Taiho Pharmaceutical Co. Ltd, Tokyo, Japan; (BMS-200604) Bristol-Myers Squibb, Princeton, NJ] administered either on a 5 or 28 day schedule and to determine the phase II trial starting doses for both schedules. Nineteen patients were entered in the 5 day schedule and 23 patients were entered on the 28 day schedule; a minimum of three patients were entered at each dose level studied. In both phase I trials, the daily UFT dose was divided into three doses administered every 8 h. Dose levels examined with the 5 day schedule were 360, 720, 900 and subsequent de-escalation to 800 mg/m2/day. Dose levels studied with the 28 day schedule were 180, 360, 450 and subsequent de-escalation to 400 mg/m2/day. With the 5 day schedule, the dose-limiting toxicity (DLT) was granulocytopenia, with four of five patients experiencing grade 4 granulocytopenia at the 900 mg/m2/day dose level. With the 28 day schedule, the DLT was diarrhea, which was noted in three of eight patients treated at 400 mg/m2/day and in three of six patients treated at 450 mg/m2/day. At these dose levels, four of these patients required prolonged hospitalizations for their diarrhea. The toxic effects of UFT are schedule dependent, with marked differences in the toxic effect profile (neutropenia versus diarrhea). With the 5 day schedule, the phase II UFT starting dose is 800 mg/m2/day. On the 28 day schedule, the suggested phase II UFT starting dose is 360 mg/m2/day. Future clinical trials examining the combination the UFT plus oral folinic acid are being conducted to develop oral regimens of therapy for advanced colorectal carcinoma and adjuvant therapy for colon carcinoma.
    Anti-Cancer Drugs 10/1996; 7(7):728-33. DOI:10.1097/00001813-199609000-00002 · 1.89 Impact Factor

Publication Stats

546 Citations
139.67 Total Impact Points


  • 1997–2012
    • University of Texas MD Anderson Cancer Center
      • Department of Gastrointestinal Medical Oncology and Digestive Diseases
      Houston, Texas, United States