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1.
Background We have conducted a phase I trial to determine the maximum tolerated dose of gemcitabine in combination with interferon, thalidomide
and capecitabine.
Methods Patients received oral capecitabine 1,000 mg/m 2 per day, divided in 2 daily doses, 2 weeks on, 1 week off; subcutaneous interferon-α 1 mIU twice a day without an interruption;
daily oral thalidomide 200 mg/day for the first 7 days, then escalated to 400 mg/day without an interruption. Gemcitabine
was given by intravenous administration over 30 min on day 1, week 1 and day 8, week 2. Initial dose level of gemcitabine
was 400 mg/m 2. The dose of gemcitabine was the phase I variable. One cycle was 3 weeks.
Results and discussion We treated 12 patients, 6 patients were entered at a dose level of 0 (gemcitabine 400 mg/m 2) and 6 patients entered at a dose level-1 (gemcitabine 200 mg/m 2). Eight of 12 patients completed at least 12 weeks of therapy. Three partial responses and two stable disease were observed.
The remaining patients had progressive disease. Non-hematologic toxicity was either grade 1 or 2. Hematologic toxicity at
dose level 0 consisted of 3 patients with grade 3/4 neutropenia, and 1 patient with grade 3 thrombocytopenia. At dose level-1
grade 1/2 neutropenia was observed.
Conclusions The completion of our phase I experience determined our maximum tolerated dose to be dose level-1. The phase II trial is currently
being proposed for patients with rapidly growing clear cell, other histologies that may contain sarcomatoid elements or collecting
duct tumor. 相似文献
2.
PURPOSE: A single-agent dose-escalating phase I and pharmacokinetic study on the farnesyl transferase inhibitor SCH 66336 was performed to determine the safety profile, maximum-tolerated dose, and recommended dose for phase II studies. Plasma and urine pharmacokinetics were determined. PATIENTS AND METHODS: SCH 66336 was given orally bid without interruption to patients with histologically or cytologically confirmed solid tumors. Routine antiemetics were not prescribed. RESULTS: Twenty-four patients were enrolled onto the study. Dose levels studied were 25, 50, 100, 200, 400, and 300 mg bid. Pharmacokinetic sampling was performed on days 1 and 15. At 400 mg bid, the dose-limiting toxicity (DLT) consisted of grade 4 vomiting, grade 4 neutropenia and thrombocytopenia, and the combination of grade 3 anorexia and diarrhea with reversible grade 3 plasma creatinine elevation. After dose reduction, at 300 mg bid, the DLTs consisted of grade 4 neutropenia, grade 3 neurocortical toxicity, and the combination of grade 3 fatigue with grade 2 nausea and diarrhea. The recommended dose for phase II studies is 200 mg bid, which was found feasible for prolonged periods of time. Pharmacokinetic analysis showed a greater than dose-proportional increase in drug exposure and peak plasma concentrations, with increased parameters at day 15 compared with day 1, indicating some accumulation on multiple dosing. Plasma half-life ranged from 4 to 11 hours and seemed to increase with increasing doses. Steady-state plasma concentrations were attained at days 7 through 14. A large volume of distribution at steady-state indicated extensive distribution outside the plasma compartment. CONCLUSION: SCH 66336 can be administered safely using a continuous oral bid dosing regimen. The recommended dose for phase II studies using this regimen is 200 mg bid. 相似文献
3.
Summary Toremifene, a new antiestrogenic antitumor compound, has several biologically active metabolites. The hormonal effects of the main metabolites resemble those of unchanged toremifene. The main metabolite in humans, N-demethyltoremifene, is bound to estrogen receptors (ER), inhibits the growth of MCF-7 cells, and exerts an antiestrogenic effect similar to that of toremifene. However, its antitumor effect in vivo against dimethyl-benz(a)anthracene (DMBA)-induced rat mammary cancers is weaker than that of toremifene. Didemethyltoremifene has antiestrogenic actions in mouse and rat uterus at high doses. 4-Hydroxytoremifene is bound to ER with higher affinity and inhibits MCF-7 growth at concentrations lower than those of toremifene. It has a weaker intrinsic estrogenic effect than does toremifene. The efficacy of 4-hydroxytoremifene against DMBA-induced cancers is weak except at very high doses. Oxidations of N-demethylated metabolites to (deamino)hydroxylated compounds and carboxylic acids are the detoxification routes of toremifene. (deaminohydroxy)Toremifene has only weak hormonal actions at high doses and carboxylated metabolites have no estrogenic/antiestrogenic effects. The antitumor effect of toremifene in vivo is mainly due to unchanged toremifene, but hormonal effects (which may have a role in antitumor actions) are partly attributable to metabolites N-demethyltoremifene, didemethyl-toremifene, (deaminohydroxy)toremifene, 4-hydroxy- N-demethyltoremifene, and 4-hydroxytoremifene, which have pharmacological properties similar to those of toremifene. 相似文献
4.
Summary Toremifene is an antiestrogen that binds strongly to estrogen receptors (ER). A total of 19 previously treated postmenopausal women with metastatic breast cancer whose performance status was good and whose ER status was positive or unknown were studied to determine the maximum tolerated dose of toremifene. Cohorts of patients received 200, 300, or 400 mg/m 2 p.o. daily until relapse or unacceptable toxicity had occurred. Nausea, vomiting, and dizziness were dose-related. Three of five patients receiving 400 mg/m 2 experienced moderate or severe vomiting and another developed reversible disorientation and hallucinations. Mild sweating, peripheral edema, vaginal discharge, and hot flushes were encountered at all doses. Reversible corneal pigmentation was identified in seven cases but was not of clinical importance. The pharmacokinetics of toremifene was studied weekly and in detail on day 42 using a high-performance liquid chromatographic (HPLC) assay that identified the parent compound and three active metabolites, N-desmethyltoremifene, (deaminohydroxy)toremifene, and didemethyltoremifene. Steady state was achieved at 1–3 weeks. The toremifene area under the curve and the maximal concentration were dose-dependent at high doses. The recommended phase II dose is 300 mg/m 2 p.o. daily.This study was supported by a grant from Farmitalia 相似文献
5.
To determine whether plasma concentrations of toremifene citrate after administration of 120 mg/day of toremifene citrate given in three separate dose (t.i.d.) were similar to those when toremifene citrate was administered in a single daily doses (40 mg x 3 tablets), we examined changes in plasma concentrations of toremifene citrate (TOR) and its metabolite, N-desmethyltoremifene (TOR-1). In both the t.i.d. administration group and the single-dose administration group, plasma TOR and TOR-1 concentrations reached a constant state within 2 weeks after administration was started. Under the constant state, plasma TOR concentrations were 1,493.3 +/- 120.3 ng/ml in the t.i.d. administration group and 1,348 +/- 341.0 ng/ml in the single-dose administration group. Plasma TOR-1 concentrations were 2,378.3 +/- 186.5 ng/ml in the t.i.d. administration group and 2,144 +/- 475.3 ng/ml in the single-dose administration group. In both groups, plasma TOR-1 concentrations were 2 or more times higher than plasma TOR concentrations. These results show there were no differences in plasma concentrations between administration of 120 mg/day of toremifene citrate in divided daily doses (t.i.d.) and in a single daily dose. The two administration methods appear to produce clinically similar actions. 相似文献
6.
BACKGROUND: Low voriconazole levels have been associated with a higher failure rate in patients with confirmed fungal infections. METHODS: Steady-state plasma trough voriconazole levels were measured after at least 5 days of therapy in 87 patients with hematologic malignancies on 201 separate occasions (1-5 levels per patient; median, 2). Most patients (90%) had undergone allogeneic hematopoietic stem cell transplantation. The daily voriconazole dose, administered in 2 divided doses, was 200 mg (n = 4), 400 mg (n = 151), 500 mg (n = 20), 600 mg (n = 18), and 800 mg (n = 8); corresponding to 2.0-16.3 (median, 5.4) mg/kg. Plasma voriconazole levels were 0-12.5 microg/mL (median, 1.2). Voriconazole was undetectable (<0.2 mug/mL) in 15%. RESULTS: The correlation between dose and levels was weak (r = 0.14; P = .045). The median absolute daily drug dose (400 mg) was identical in groups of patients with levels of 0, 0.2 to 0.5, >0.5 to 2.0, >2.0 to 5.0, and >5.0. Whereas the daily drug dose in mg/kg was significantly higher when the levels were >5.0 microg/mL, there was no consistent relation between dose and level below that threshold. In adult patients getting standard doses of voriconazole orally, the drug levels are highly variable. Based on limited available data, between a quarter and two-thirds of these levels could potentially be associated with a lower likelihood of response or a higher likelihood of failure. CONCLUSIONS: Future voriconazole studies should incorporate prospective therapeutic drug monitoring and consideration should be given to checking levels in patients receiving the drug for confirmed, life-threatening fungal infections. 相似文献
7.
Purpose: We conducted a Phase I study of bischloroethylnitrosourea (BCNU), cisplatin, and oral etoposide administered prior to and during accelerated hyperfractionated radiation therapy in newly diagnosed high-grade glioma. Pharmacokinetic studies of oral etoposide were also done. Methods and Materials: Patients started chemotherapy after surgery but prior to definitive radiation therapy (160 cGy twice daily × 15 days; 4800 cGy total). Initial chemotherapy consisted of BCNU 40 mg/m2 days 1–3, cisplatin 30 mg/m2 days 1–3 and 29–31, and etoposide 50 mg orally days 1–14 and 29–42, repeated in 8 weeks concurrent with radiation therapy. BCNU 200 mg/m2 every 8 weeks × 4 cycles was given after radiation therapy. Results: Sixteen patients, 5 with grade 3 anaplastic astrocytoma and 11 with glioblastoma were studied. Grade 3–4 leukopenia (38%) and thrombocytopenia (31%) were dose-limiting. Other toxicities were anorexia (81%), nausea (94%), emesis (56%), alopecia (88%), and ototoxicity (38%). The maximum tolerated dose was BCNU 40 mg/m2 days 1–3, cisplatin 20 mg/m2 days 1–3 and 29–31, and oral etoposide 50 mg days 1–21 and 29–49 prior to radiation therapy and repeated in 8 weeks with the start of radiation therapy followed by BCNU 200 mg/m2 every 8 weeks for 4 cycles. Median time to progression and survival were 13 and 14 months respectively. Responses occurred in 2 of 9 (22%) patients with evaluable disease. In pharmacokinetic studies, all patients achieved plasma concentrations of >0.1 μg/ml etoposide (the in vitro radiosensitizing threshold), following a 50 mg oral dose. The mean ± SD 2 hr and 6 hr plasma concentrations were 0.92 ± 0.43 μg/ml and 0.36 ± 0.12 μg/ml, respectively. Estimated duration of exposure to >0.1 μg/ml etoposide was 10–17 hr. Conclusions: Preirradiation chemotherapy with BCNU, cisplatin, and oral etoposide with accelerated hyperfractionated radiation therapy in high-grade gliomas is feasible and merits further investigation. Sustained radiosensitizing concentrations can be achieved with low oral doses of etoposide. 相似文献
8.
BACKGROUND: A phase I clinical study of combination chemotherapy with docetaxel and cyclophosphamide (CPA) was performed to determine the maximum tolerated dose (MTD), the incidence and severity of toxicities and the pharmacokinetics in patients with advanced or recurrent breast cancer. METHODS: Docetaxel was administered by intravenous drip infusion over 60 minutes, followed by intravenous bolus injection of CPA every 3-4 weeks. The dosage of docetaxel/CPA was 40/200, 40/400, 50/400, or 60/400 mg/m(2)/day. RESULTS: Fifteen patients were enrolled and received a total of 33 cycles of the combined therapy. The dose limiting toxicities (DLTs) were leukopenia, neutropenia and thrombocytopenia. The MTD was estimated to be docetaxel 60 mg/m(2) in combination with CPA 400 mg/m(2) per day. Plasma clearance of both drugs was similar regardless of dose. The recommended doses of docetaxel/CPA for a phase Utrial are 50/400 mg/m(2)/day every 3-4 weeks. CONCLUSION: The MTD of this combined therapy was docetaxel 60 mg/m(2) and CPA 400 mg/m(2). Neutropenia and leukopeina were common and severe. It is important to stress the need for modification of the dosing scheme. 相似文献
9.
BackgroundThis is a phase I/II trial of thalidomide with estramustine and paclitaxel in men with androgen-independent prostate cancer (AIPC) who underwent previous chemotherapy. Patients and MethodsMen with progressive AIPC were treated with oral thalidomide (200 mg, 400 mg, or 600 mg daily), intravenous paclitaxel (100 mg/m 2 over 3 hours on days 3 and 10), and oral estramustine (140 mg 3 times daily on days 1-5 and days 8-12) every 21 days. ResultsPhase I: first cycle dose-limiting toxicity occurred in 0 of 3 patients at 200 mg thalidomide daily, 0 of 3 at 400 mg daily, and 1 of 3 at 600 mg daily (the designated maximum tolerated dose). Phase II: twenty-nine of 38 evaluable patients (76%; 95% confidence interval, 67%-87%) experienced a 50% decrease in prostate-specific antigen level. Five of 18 patients (28%) with measurable disease exhibited an objective response. Nine of 14 patients (64%) with disease refractory to previous taxane therapy had 50% decreases in prostate-specific antigen level. Grade 3/4 adverse events included neutropenia (9 of 39 [23%]), fatigue (9 of 39 [23%]), dyspnea (8 of 39 [21%]), and thromboembolic events (7 of 39 [18%]). Cumulative dose-limiting toxicity rates were minimal (13%) with thalidomide at 200 mg daily. ConclusionThe profile of activity of thalidomide/paclitaxel/estramustine in taxane-refractory AIPC warrants further investigation. 相似文献
10.
A Phase I trial (NCT00109109) of oral vorinostat 200, 250 or 300 mg twice daily for 5 days/week/4-week cycle or 200, 300, or 400 mg twice daily for 14 days/3-week cycle until progressive disease or intolerable toxicity was conducted. Patients with measurable, relapsed/refractory multiple myeloma were eligible. The objectives were to determine maximum tolerated doses (MTDs) and assess activity and safety. Thirteen patients (median age, 63 years; median prior therapies, 3) were enrolled. MTDs were not determined due to early study termination by sponsor decision. One patient (250 mg twice daily 5 days/week) developed dose-limiting toxicity (DLT; grade 3 fatigue). There were no other DLTs and the maximum administered doses were 250 mg twice daily for 5 days/week/4-week cycle and 200 mg twice daily for 14 days/3-week cycle. Drug-related adverse experiences included fatigue, anorexia, dehydration, diarrhea, and nausea and were mostly grade ≤2. Of 10 evaluable patients, 1 had a minimal response and 9 had stable disease, demonstrating modest single-agent activity in relapsed/refractory multiple myeloma. 相似文献
11.
PURPOSE: The aim of this study was to determine the daily maximum tolerated dose (MTD) and the dose-limiting toxicity for the following administration schedules: oral irinotecan given over 14 days every 3 weeks (part I) and oral irinotecan administered concomitantly with capecitabine over 14 days every 3 weeks (part II). In total, 42 patients (17 male and 25 female) with solid tumors refractory to standard therapy entered the study. EXPERIMENTAL DESIGN: Treatment in part I consisted of irinotecan administered orally as semisolid matrix capsules at doses of 25, 30, and 35 mg/m(2) once daily to confirm the MTD of our earlier study. In part II treatment, dose levels for irinotecan combined with capecitabine were 20/1,600, 25/1,600, 30/1,600, and 30/2,000 mg/m(2)/d. RESULTS: The median number of cycles administered per patient was 2.0 (range, 1-12) in part I and 2.0 (range, 1-13) in study part II. Gastrointestinal toxicities (grade 3 nausea, grades 3 and 4 vomiting, and grades 3 and 4 diarrhea) were dose limiting in both parts of the study. There were no grade 3 or 4 hematologic toxicities. The MTD was 30 mg/m(2)/d for irinotecan single agent and 30/1,600 mg/m(2)/d for the combination with capecitabine. Absorption of irinotecan was rapid, and peak concentrations of irinotecan and metabolite SN-38 were reached within 0 to 3 and 1.5 to 4.0 hours, respectively. CONCLUSIONS: In conclusion, oral irinotecan and capecitabine is feasible and well tolerated, and the recommended dose for phase II studies is 30/1,600 mg/m(2)/d administered daily for 14 days every 3 weeks. 相似文献
12.
BackgroundThis is a phase I/II trial of thalidomide with estramustine and paclitaxel in men with androgen-independent prostate cancer (AIPC) who underwent previous chemotherapy. Patients and MethodsMen with progressive AIPC were treated with oral thalidomide (200 mg, 400 mg, or 600 mg daily), intravenous paclitaxel (100 mg/m 2 over 3 hours on days 3 and 10), and oral estramustine (140 mg 3 times daily on days 1-5 and days 8-12) every 21 days. ResultsPhase I: first cycle dose-limiting toxicity occurred in 0 of 3 patients at 200 mg thalidomide daily, 0 of 3 at 400 mg daily, and 1 of 3 at 600 mg daily (the designated maximum tolerated dose). Phase II: twenty-nine of 38 evaluable patients (76%; 95% confidence interval, 67%-87%) experienced a 50% decrease in prostate-specific antigen level. Five of 18 patients (28%) with measurable disease exhibited an objective response. Nine of 14 patients (64%) with disease refractory to previous taxane therapy had 50% decreases in prostate-specific antigen level. Grade 3/4 adverse events included neutropenia (9 of 39 [23%]), fatigue (9 of 39 [23%]), dyspnea (8 of 39 [21%]), and thromboembolic events (7 of 39 [18%]). Cumulative dose-limiting toxicity rates were minimal (13%) with thalidomide at 200 mg daily. ConclusionThe profile of activity of thalidomide/paclitaxel/estramustine in taxane-refractory AIPC warrants further investigation. 相似文献
13.
Summary In pre-clinical and limited clinical studies, high doses ( 200 mg/day) of the triphenylethylene derivative toremifene showed activity in estrogen receptor (ER) negative and ER-unknown metastatic breast cancer after progression on tamoxifen, and a mechanism of action independent of hormone receptor binding was speculated. The CALGB conducted a Phase II trial (CALGB 8945) to test the efficacy of high dose toremifene in a population of patients who had hormone receptor-negative, metastatic breast cancer with limited prior chemotherapy exposure, good performance status, and measurable disease. Twenty eligible patients received toremifene at a dose of 400 mg/day orally for 8 weeks. Toxicity was minimal. Nausea was reported by 20% of the patients, lightheadedness by 20%, weight loss by 20%, and hot flashes by 15%. There was no grade 3–4 toxicity. No objective responses were observed, and 5 of 6 patients with stable disease at 8 weeks developed progressive disease at 11 to 33 weeks. High dose toremifene (400 mg/day) is well-tolerated but imparts no detectable activity in hormone receptor-negative, metastatic breast cancer. 相似文献
14.
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/m 2/day, with planned escalations to 250, 300, 350, and 400 mg/m 2/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/m 2/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/m 2 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/m 2/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. 相似文献
15.
Vorinostat (suberoylanilide hydroxamic acid), a potent, oral histone deacetylase inhibitor, has demonstrated clinical activity in non-Japanese patients with various hematological and solid tumors. We sought to determine the maximum tolerated dose and a recommended phase II dose for 18 Japanese patients with solid tumors (median age, 58 years; range, 25–72 years) who failed standard therapy. Patients received vorinostat for 14 days followed by a 7-day rest. The initial dose was 100 mg twice daily escalating by 100 mg twice daily. Once-daily dosing was tested at 400 and 500 mg. A maximum tolerated dose could not be identified. Dose-limiting toxicities (thrombocytopenia, anorexia, and fatigue) were observed in two of six patients receiving 200 mg twice daily and in one of six patients receiving 500 mg once daily. In the 100–500 mg dose range, vorinostat area under the concentration–time curve increased in proportion to dose with a pharmacokinetic profile similar to that established in non-Japanese patients. Vorinostat doses of 200 mg twice daily or 500 mg once daily for 14 days followed by a 7-day rest were well tolerated and are candidate doses for phase II trials, although a maximum tolerated dose for vorinostat was not reached. ( Cancer Sci 2009; 100: 1728–1734) 相似文献
16.
Plasma lonidamine concentration and toxicity were investigated in dogs receiving 100, 200, 400, 800, 1200 mg/m 2 orally twice daily for 30 days and in dogs receiving single intravenous doses of 200, 400, 800, 1200 mg/m 2. Physical or laboratory signs of toxicity were not observed in dogs receiving oral lonidamine, but severe vomiting and signs
of acute hepatic and pancreatic toxicity were observed in dogs receiving intravenous doses that exceeded 400 mg/m 2. The area under the lonidamine concentration versus time curve (AUC) in dogs receiving 200, 400, and 800 mg/m 2 of lonidamine intravenously was a 1.8-, 3.3-, and 8.7-fold higher than in dogs receiving oral lonidamine. This suggests that
the bioavailability of oral lonidamine may be limited. However, centrilobular hepatocellular swelling and vacuolation were
observed in dogs receiving oral lonidamine. Serum alanine aminotransferase (ALT) activity was increased in dogs receiving
intra-venous lonidamine. These findings suggest that lonidamine is hepatotoxic in dogs. However, serum ALT was increased in
only 1/4 dogs receiving 400 mg/m 2 of lonidamine intravenously and plasma concentration were within the range capable of sensitizing hyperthermia and chemotherapy.
Therefore, this dose and route appears to be a viable and controllable method for prospective quantification of lonidamine
interaction with systemic chemotherapy and/or hyperthermia.
Received: 8 October 1993 /Accepted: 9 October 1995 相似文献
17.
Treatment options for patients with metastatic renal cell carcinoma are limited. Interferon-alpha has an overall response rate of 10-15% in phase II and III clinical trials and is considered a standard option for patients. Though the anti-estrogen toremifene has shown only modest single agent activity in renal cell carcinoma, evidence for synergy of anti-estrogens with interferon-alpha exists in renal cell and other cancers. Therefore, a phase II trial was undertaken to test the combination of interferon-alpha and toremifene in advanced renal cell carcinoma. Thirteen patients with measurable metastatic or unresectable local disease were treated with interferon-alpha at a dose of 5 million units/m 2 three times a week and daily oral toremifene at 300 mg daily in divided doses. Patients were treated for 12 weeks and then restaged. Clinical response was the primary endpoint of the trial. Four patients (31%) had evidence of stable disease at 12 weeks, while the remaining nine patients (69%) progressed on treatment. Toxicity was moderate, with grade 2 or 3 fatigue, nausea and anorexia each noted in 31% of patients. We conclude that the combination of interferon-alpha plus toremifene demonstrates no significant activity in advanced renal cell carcinoma. 相似文献
18.
Side effects have been observed when 14-membered macrolides, erythromycin and troleandromycin, have been prescribed concurrently in patients receiving therapeutic doses of theophylline. Rokitamycin is a new 16-membered macrolide antibiotic. We have evaluated its effect on theophylline serum concentrations in 12 adult patients suffering from chronic obstructive pulmonary disease. Initially, six patients were treated for four consecutive days with theophylline as sustained-release formulation in the amount of 600 mg daily; six other patients received for four consecutive days a short term intravenous infusion of 240 mg aminophylline, given over a period of 30 min twice daily. On the last day, blood samples were taken for theophylline determination. Theophylline concentrations were measured serially for 12 hours after oral formulation and 4 hours after aminophylline by enzyme immunoassay technique. Subsequently, while theophylline and aminophylline treatments were continued at the same dosage, each patient received in addition rokitamycin tablets, 400 mg every 12 hours. After seven days of this combined medication, the serial assays of serum theophylline were repeated at the same time intervals as before. Concomitant administration of therapeutic doses of rokitamycin did not affect significantly the steady-state pharmacokinetics of oral theophylline and did not alter the (pseudo-) steady-state pharmacokinetics of intravenous aminophylline, showing that the two drugs may be coadministered without any theophylline dose adjustment. 相似文献
19.
Triphenylethylene compounds, such as tamoxifen, have shown chemosensitizing activity independent of estrogen receptor status in doxorubicin-resistant cells. We examined the chemosensitizing activity of a new triphenylethylene, toremifene, and its major metabolites in a doxorubicin-resistant human breast cell line, MCF-7/DOX. In addition, we examined the chemosensitizing activity of unbound plasma toremifene and its metabolites isolated from patients treated with toremifene doses of 20 to 400 mg/d. MCF-7/DOX cells were exposed to ultrafiltrate plasma specimens in the absence and presence of doxorubicin. These latter studies were single-blinded. Toremifene and its major metabolites were capable of sensitizing multidrug-resistant cells to doxorubicin. The degree of chemosensitizing activity in vitro correlated with the plasma concentrations of toremifene and its metabolites (P less than .05). Plasma samples isolated from patients receiving high-dose toremifene (400 mg/d) had the greatest chemosensitizing activity. We present evidence that toremifene and its metabolites can sensitize resistant MCF-7/DOX cells to doxorubicin, that this effect is concentration-dependent, and that sensitizing activity can be detected at clinically achieved concentrations. 相似文献
20.
N-Methylformamide (NMF) has been an agent of considerable interest to oncologists because of its broad spectrum of preclinical antitumor activity, tumor-differentiating abilities, and radiosensitizing and chemosensitizing properties. In this report, the pharmacokinetics of NMF are described, based on data from two phase I studies exploring both iv and oral routes of administration. Mean peak NMF plasma concentrations at recommended phase II doses were 0.46 mmol/L for NMF administered orally, 600 mg/m2 three times/week X 4 weeks every 6 weeks, and 2.78 mmol/L for NMF administered as a weekly iv bolus at 2,000 mg/m2 X 3 weeks every 4 weeks. These NMF concentrations were significantly lower than the concentrations that have been demonstrated to induce antineoplastic and relevant biologic effects in preclinical studies. Plasma disappearance curves were biphasic in the majority of patients; however, 25% of the curves were best fit by a monoexponential kinetic model. Mean alpha half-life and beta half-life values (+/- SE) were 10 +/- 2 and 732 +/- 93 min, respectively. Volumes of distribution for the theoretical central compartment (Vc) and at steady-state (Vss) were 13.8 +/- 1.1 L/m2 and 18.7 +/- 1.1 L/m2, respectively. The mean plasma clearance of NMF was 19.1 +/- 2.1 mL/min per square meter, and the relative contributions to parent compound disposition by respiratory and renal routes were insignificant. No metabolites were identified. Gastrointestinal absorption of oral NMF was rapid and nearly complete; oral bioavailability was calculated to be 0.87. Pharmacodynamic associations were observed between the magnitude of the area under the plasma disappearance curves and hepatotoxicity, the dose-limiting toxic effect of iv NMF, and the symptom complex of nausea, vomiting, and malaise, which precluded dose escalation of oral NMF. 相似文献
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