Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027947 (neutropenia)
 17,527 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Topotecan is a semi-synthetic, water soluble topoisomerase I inhibitor which has recently been approved for the treatment of ovarian cancers after failure of first-line therapy. A number of different dosing schedules are being investigated in clinical trials including oral administration, a daily infusion on 5- or 3-consecutive days and a continuous infusion for 21 days. A 30-minute infusion of topotecan 1.5 mg/m2 on 5 consecutive days every 3 weeks, as standard schedule, produced response rates of 13.8 to 20.5% in the 3 largest phase II/III studies in women with advanced ovarian cancers who had either failed to respond or had relapsed after an initial response to platinum-based chemotherapy (N = 92 to 139), continuous 21-day infusion of topotecan 0.3 to 0.5 mg/m2 has shown efficacy in 2 small phase II studies. There were no statistically significant difference in efficacy between topotecan (1.5 mg/m2/day for 5 consecutive days every 21 days) and paclitaxel (175 mg/m2/day given over 3-h every 21 days) in the randomized phase III study. In 3 large clinical trials, response to topotecan was higher in patients who were platinum sensitive (19.2 to 29%) than in those whose disease was platinum resistant or refractory (11.3 to 13.3%) not statistically significant in 1 study, statistical analysis not reported in the other 2 trials. Myelosuppression, particularly neutropenia, is the dose-limiting toxicity of topotecan. It is reversible, dose-related and non-cumulative. In 2 large studies, topotecan produced grade 4 neutropenia in 78 and 79% of patients and in 40 and 37% of all treatment courses (febrile neutropenia occurred during 3% of 552 courses in 1 study). Grade 4 thrombocytopenia was seen in 18 and 25% of patients and in 6 and 10% of all courses, respectively. Grade 4 neutropenia was significantly more common in patients receiving topotecan than in those receiving paclitaxel (79 vs 23%), as was grade 4 thrombocytopenia (25 vs 2%), in a single randomized clinical trial. Non-hematological adverse events during topotecan therapy were mostly mild. A step beyond is the combination treatment including topotecan as a 3- or 5 days schedule plus a platinum compounds or topoisomerase II inhibitor. These associations of drugs are based on the preclinical data of the in vitro studies showing a synergy of the anti-tumor activity. A novel schedule of topotecan is also the "alternating" chemotherapy consisting of different doublet of drugs given as a sequential way or as a really sequential topotecan therapy. Both methods of combining topotecan as second/salvage treatment or front line therapy are being investigated by numerous authors. Preliminary data suggest interesting results in terms of efficacy, manageable toxicity and new schedules of treatment for topotecan. Low dosages of drug in combination with other agent do not seem to influence the well-known data of efficacy or safety of topotecan literature. Probably the 3-day schedule allows a combination treatment, otherwise not feasible with the standard 5-day administration.
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PMID:[Topotecan: prospects for using it in combination therapy for ovarian carcinoma]. 1078 95

Various active compounds (or their semi-synthetic derivatives) derived from medicinal plants have been assessed for their efficacy and tolerability in the treatment of breast cancer. Some of these plant species, including Taxus baccata (paclitaxel, docetaxel), Podophyllum peltatum (etoposide), Camptotheca acuminata (camptothecin) and Vinca rosea (vinblastine, vinorelbine) have well recognized antitumour activity in breast cancer, and have been evaluated in clinical trials. For example, results from recent Phase II/III trials have established docetaxel as the most active single agent in the treatment (first or second-line) of advanced metastatic breast cancer. For other plant species such as Panax ginseng and Allium sativum, antitumour activity has been evaluated in experimental studies using cultured cells and animal models, but the therapeutic potential in patients remains to be determined. Antitumour activity derived from medicinal plants may produce results via a number of mechanisms, including effects on cytoskeletal proteins which play a key role in mitosis (paclitaxel), inhibition of activity of topoisomerase enzymes I (camptothecin) or II (etoposide), stimulation of the immune system (Viscum album), or antiprotease-antioxidant activity. Medicinal plant-derived antineoplastic agents may be used in single agent or in combinational therapies, and have been used in first-line or second-line (including anthracycline-refractory patients) treatment of localized or metastatic breast cancer. Adverse effects resulting from the use of these agents include neutropenia and peripheral neuropathies.
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PMID:Therapeutic applications of medicinal plants in the treatment of breast cancer: a review of their pharmacology, efficacy and tolerability. 1105 61

The binding of camptothecin (CPT) to the DNA-topoisomerase complex is reversible, but it needs to be maintained for maximal inhibitory activity. It is also dependent on the chemical structure of CPT. The lactone form is thought to be necessary for the activity. In human serum, the equilibrium between lactone and carboxylate is in favor of the latter. For these reasons, alternative administration of CPT analogues is being evaluated. The ideal compound would remain in lactone form and would expose the host for long periods of time to its effects. Oral administration of irinotecan (CPT-11) and topotecan (TPT) is discussed by other investigators. We studied oral rubitecan and reported a low lactone to total drug area under the plasma concentration-time curve (AUCP) ratio (14.7%), with low plasma concentration over time despite repeated administrations and the presence of an enterohepatic cycle. Aerosolization of a liposomal formulation of rubitecan is currently under study. Six patients have been treated once a day for 5 days every 3 weeks. The dose was 6.7 micrograms/kg/day. Plasma levels are dose for dose higher than those after oral administration, but the ratio of lactone versus total drug is low. No toxicity was observed. The study will continue with increasing doses and lengths of administration. Intrathecal administration of topotecan has been studied in a phase I trial in children. Doses of 0.4 mg are tolerated without toxicity, and clinical responses have been seen in patients with refractory meningial carcinomatosis. Phase II studies are planned. Intraperitoneal (i.p.) administration of topotecan has been studied in a phase I trial as a 24-hour infusion in 5% dextrose at pH 3.5 every 21 days. Dose-limiting toxicity is 4 mg/m2. Toxic effects are neutropenia, anemia, emesis, fever, and pain. Five of 10 patients with ascites had symptomatic relief. Pharmacokinetic analysis demonstrates a second-order kinetics with elimination half-lives of 0.49 and 2.7 hours. The peritoneal to plasma AUC ratio was 31.2. Intramuscular, transdermal, and subcutaneous administrations have been extensively studied in the mouse.
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PMID:Alternative administration of camptothecin analogues. 1119 99

Recurrent or metastatic squamous carcinoma of the head and neck (RMSCHN) is a modestly chemoresponsive tumor; however, currently available agents have failed to improve survival. New active agents are needed for the treatment of this disease. Topotecan is a topoisomerase inhibitor that demonstrated initial promising activity in squamous carcinoma of the head and neck. The Eastern Cooperative Oncology Group conducted a phase II trial of topotecan to determine the efficacy and toxicity of a weekly treatment schedule in patients with RMSCHN. Patients with metastatic or locally recurrent squamous carcinoma of the head and neck were treated with topotecan 1.5 mg/m2 x 24 hours by continuous infusion on days 1, 8, 15, and 22 of each 35-day cycle. Patients were stratified in two cohorts: chemonaive and previously treated. Sixteen chemonaive and 16 previously treated patients were registered on study. Grade III/IV neutropenia and anemia occurred in 16% and 18% of patients, respectively. No responses were observed in either cohort. Median survival for previously untreated patients was 4.6 months and 3.2 months for previously treated patients. Topotecan failed to demonstrate efficacy in patients with RMSCHN. Further evaluation of this agent is not planned.
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PMID:Lack of efficacy of topotecan in the treatment of metastatic or recurrent squamous carcinoma of the head and neck: an Eastern Cooperative Oncology Group Trial (E3393). 1123 52

Inhibition of topoisomerase I by topotecan results in a compensatory increase in topoisomerase II levels associated with increased in vitro sensitivity of tumors to etoposide. Maximum synergy has been observed for the sequence of topotecan followed by etoposide. This is the pharmacologic rationale for the sequence of topotecan 0.4 mg/m(2) per day for 7 days continuous i.v. infusion, carboplatin i.v. on day 8, and etoposide 50 mg per day p.o. days 9 through 20. The carboplatin dosage was escalated from an AUC of 4 to 5 to 6 (Calvert formula). Up to six treatment cycles were administered at 28-day intervals. Eligible patients had metastatic non-small cell lung cancer (NSCLC) or extensive disease small lung cell lung cancer (SCLC), no prior chemotherapy, performance status 0-2, and adequate organ function. Follow-up was twice weekly in the first cycle for CBC and for topotecan and etoposide concentrations. Follow-up, thereafter, was weekly. Tumor response was assessed after two and six cycles and then as clinically indicated. At carboplatin AUCs of 4 and 5, no NCI grade 4 toxicity was observed in cycle 1 in cohorts of three patients each. At the AUC of 5, two patients experienced dose-limiting events after cycle 3, one grade 4 neutropenia lasting >3 days (no fever) and one failure to recover an absolute neutrophil count >1500/microl by day 35. This was, therefore, deemed the maximal tolerable dose. Number of treatment cycles per patient ranged between 1 and 6, and three patients completed six cycles. All patients were male, age 47-71, with NSCLC in one and SCLC in six. The patient with NSCLC had progressive disease after one cycle. One complete and three partial responses were observed in five patients with SCLC. Mean steady-state plasma concentrations during topotecan infusion ranged from 0.73 to 1.69 ng/ml, and mean etoposide concentrations ranged from 60 to 230 ng/ml. This sequence of topotecan, carboplatin, and etoposide appeared tolerable and active. Neutropenia was the dose-limiting toxicity.
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PMID:Phase I and pharmacologic study of sequential topotecan, carboplatin, and etoposide. 1155 19

Topotecan is a topoisomerase-I inhibitor, a drug that stabilizes a covalent complex of enzymes and causes strand cleavage of DNA. 5-Fluorouracil (5FU) is an antimetabolite that interferes with DNA synthesis. Preclinical studies using human cancer cell line models have shown potential therapeutic synergy between these two drugs by showing the maximum cytolytic effect using sequential 5FU followed by topotecan. In the current study, 5FU was used at a fixed dose of 375 mg/m2 given intravenously for five consecutive days on a 28 day cycle. Topotecan was dose-escalated in cohorts of patients from 0.5 to 1.0 mg/m2 given intravenously for 5 days after the 5FU dose. Eleven patients were entered at different dose levels. Both hematological and gastrointestinal toxicity were dose limiting. Diarrhea was the dose-limiting toxicity at the dose of 0.75 mg/m2 of topotecan. Two cases of grade 4 neutropenia were also observed at this dose level. One patient with small cell lung cancer had a complete response, while one patient with metastatic colorectal cancer had a partial remission. Three other patients had stable disease, lasting between 6 and 8 months. Overall, the regimen was well tolerated. A phase II study using a dose of 5FU at 375 mg/m2 followed by topotecan at 0.75 mg/m2 intravenously over 5 days every 28 days is recommended.
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PMID:Phase I study of sequential administration of topotecan and 5-fluorouracil in patients with advanced malignancies. 1219 19

Preliminary results indicate that inhibitors of the nuclear enzyme topoisomerase (topo) I, such as topotecan, may be active in non-Hodgkin's lymphoma (NHL). Pre-clinical studies have shown sequential administration of a topo I and II inhibitor has supra-additive anti-tumor effects in some model systems, and that greater cytotoxicity occurs if the topo I inhibitor is given first. We enrolled, 22 eligible patients with relapsed or refractory intermediate grade NHL in a phase II study ofsequential administration of topotecan 1.25 mg/m2 days 1-5 and etoposide 50 mg po b.i.d. days 6-12, every 28 days without G-CSF. Most patients had diffuse large B-cell lymphoma and all had received only one prior regimen (CHOP, 20 patients, or equivalent, 2 patients). Patients with stable or responding disease were allowed to proceed to high-dose therapy and autologous stem-cell transplant after 2 cycles of therapy. The 22 patients received a total of 62 cycles of topotecan + etoposide (median 2, range 1-6), and 4/22 completed all six planned cycles. Hematologic toxicity was significant and resulted in incomplete etoposide dosing in half of all cycles in 16/22 patients. Nineteen of twenty-two patients had grade 3/4 neutropenia, 12 had grade 3/4 thrombocytopenia, and 6 grade 3/4 anemia. Eleven patients had at least one episode of febrile neutropenia or had documented infection. Non-hematologic toxicity was mild. Four patients had a partial response (PR) (18.2%), nine had stable disease and seven progressed; three patients with stable disease went on to ABMT. The combination of topotecan and etoposide as given in this study has modest activity in relapsed/refractory aggressive histology NHL, and produces marked myelosuppression. Other doses and schedules combining topo I and II inhibitors, or topo I inhibitors with alkylating agents, should be explored with the addition of hematopoietic growth factors in this patient population.
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PMID:Phase II study of sequential topotecan and etoposide in patients with intermediate grade non-Hodgkin's lymphoma: a National Cancer Institute of Canada Clinical Trials Group study. 1240 Jun

Preclinical data suggest that the combination of inhibitors of topoisomerases I and II may be synergistic when administered together. The optimal sequence of such combinations is uncertain, but initial administration of a topoisomerase I inhibitor upregulates topoisomerase II. Several combinations of these inhibitors have been evaluated, but have not clearly demonstrated synergy. Thus, we have started a phase I study of the combination of irinotecan (CPT-11, Camptosar) and epirubicin (Ellence). Typical eligibility criteria for phase I studies were employed. Patients with a history of congestive heart failure, > 240 mg/m2 of prior doxorubicin, or > 10% weight loss in the prior 4 weeks were excluded. Irinotecan and epirubicin were administered on days 1 and 8, every 28 days. Initially, patients were treated with irinotecan at 100 mg/m2 and epirubicin at 40 mg/m2 (dose level 1). After substantial toxicity at this level, the doses to be evaluated were changed to irinotecan: 50-->75-->100 mg/m2, and epirubicin: 20-->25-->30 mg/m2. Dose-limiting toxicities were noted in 2/4 patients (2 neutropenic fever, 1 thrombocytopenia) on dose level 1; 0/3 on dose level 1A; 1/8 (neutropenia) on dose level 2A; and 1/3 (neutropenia) on dose level 3A. This is the first combination of irinotecan and epirubicin to be evaluated in humans. The toxicity, primarily myelosuppression, noted to date has exceeded the expected toxicity for the doses of the irinotecan and epirubicin alone, suggesting the possibility of a synergistic interaction of the agents on this schedule, at least in the bone marrow. Other toxicities were acceptable and non-dose-limiting. Accrual of patients continues, at level 3A (irinotecan at 75 mg/m2, epirubicin at 25 mg/m2).
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PMID:Combined inhibition of topoisomerases: a phase I. Study of irinotecan and epirubicin. 1280 Jun 7

We present the results of a phase II trial of carboplatin and etoposide (CE) combination as first-line chemotherapy in patients with recurrent glioblastoma multiforme (GBM) and anaplastic astrocytoma (AA) after surgery and radiotherapy. We assess the activity and the tolerability of this combination. 30 patients with GBM (25) and AA (5) were treated with VP-16 (etoposide) 120 mg m(-2) and CBCDA (carboplatin) 100 mg m(-2) for 3 days every 4 weeks. Moreover, we performed a retrospective analysis of topoisomerase IIalpha gene status using chromogenic in situ hybridisation. The median age was 54 years (21-73 years); Eastern Cooperative Oncology Group performance score was 0-1 in 25 patients and 2 in five patients. All patients had been previously treated with surgical resection (21 radical resections) followed by radiation therapy (40-60 Gy). We observed six (20%) complete responses, three (10%) partial responses and 12 (40%) stable diseases, with a response rate of 30%. The median time to progression was 4 months, while progression-free survival at 6 months was 33.3%. The median survival time was 10 months. Neutropenia occurred in 9 patients: four patients had grade 4, two patients grade 3 and three patients grade 2. In the conclusion of this clinical trial, the CE combination has shown activity in recurrent GBM and AA, with a good toxicity profile. Alterations in the copy number of topoisomerase IIalpha gene seem to be a rare event and in our series do not influence response to the CE combination.
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PMID:Phase II trial of carboplatin and etoposide for patients with recurrent high-grade glioma. 1530 87

The toxicity of irinotecan (CPT-11), a topoisomerase-I inhibitor largely used in cancer patients, was investigated as a function of the circadian time of its administration in mice, with mortality, body weight loss, leukopenia, neutropenia, intestinal lesions, and bone marrow cell cycle phase distribution as end points. Four experiments were performed on a total of 773 male mice standardized with 12h light/12h darkness. Irinotecan was administered daily for 4 or 10 consecutive days (D1-4 and D1-10, respectively, in different experiments) at one of six circadian stages expressed in hours after light onset (HALO). The survival curves differed significantly as a function of the dosage and circadian time of drug administration by the D1-10 schedule, with 70% survival at 7 or 11 HALO and 51% at 19 or 23 HALO (p=0.039 from log rank test). CPT-11 administration at 19 or 23 HALO resulted in (1) greatest mean body weight loss at nadir; (2) most severe colic and bone marrow lesions and/or slowest recovery; and (3) deepest neutropenia nadir and/or slowest hematologic recovery. These circadian treatment time-related differences were statistically validated. The bone marrow cell cycle data revealed a four to eight-fold larger G2-M phase arrest following irinotecan administration at 19 or 23 HALO in comparison to the other times of drug administration, apparently representative of the repair of more extensive DNA damage (p < 0.001 from ANOVA) when the medication was given at these circadian times. Overall, CPT-11 was better tolerated by mice treated during the light (animals' rest) span. The results support the administration of CPT-11 to cancer patients in the second half of the night, during sleep, in order to improve drug tolerability.
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PMID:Circadian rhythm of irinotecan tolerability in mice. 1547 Sep 58


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