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Results for “Maximum Tolerated Dose”

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At least 127 records · Page 7Linked to original sources

PubMed1995

Phase I clinical study with 8-chloro-cAMP and evaluation of immunological effects in cancer patients

The site-selective cyclic AMP analogue 8-chloro-cAMP (8-Cl-cAMP) is able to inhibit the growth of a wide variety of cancer cell lines in vitro and in vivo. 8-Cl-cAMP has been extensively investigated as a new potential anticancer agent and, more recently, preclinical Phase I studies have been conducted in animal models to study its toxicity. We have conducted the first Phase I trial with 8-Cl-cAMP to define the maximum tolerated dose, toxicity, plasma drug levels, and immunological effects in patients with cancers refractory to standard treatments. We have administered 36 courses of 8-Cl-cAMP to 17 patients by continous i.v. infusion of the drug for 5 days/week for 2 weeks followed by a 1-week rest period. Six increasing dose levels, from 0.01 to 0.25 mg/kg/h, were explored. Drug plasma levels were determined and the expression of interleukin 2 receptor alpha amount of natural killer cells, and cytolytic activity against K562 cells were measured in peripheral blood lymphocytes. A grade 4 and a grade 3 increase in serum creatinine and a grade 2 increase in blood urea nitrogen observed in two patients were the dose-limiting toxicity. The maximum tolerated dose (0.2 mg/kg/h) determined a grade 1 increase in serum creatinine. An increase in calcium levels was observed in several patients. The 8-Cl-cAMP plasma concentrations obtained at the steady state were in the range previously shown to be effective for cancer cell growth inhibition in vitro. Interleukin 2 receptor alpha expression, natural killer cell number, and cytolytic activity from peripheral blood lymphocytes were markedly increased after 8-Cl-cAMP administration at all dose levels. In conclusion, at doses below the maximum tolerated dose, 8-Cl-cAMP was not toxic but reached plasma concentrations in the potential therapeutic range for growth inhibition. Moreover, 8-Cl-cAMP determined a marked biomodulatory effect and showed antitumor activity.

Journal Article↗

PubMedDate not supplied

A randomized, double-blind, placebo-controlled, ascending-dose tolerability and safety study of remacemide as adjuvant therapy in Parkinson's disease with response fluctuations.

The objective of this study was to establish the maximum tolerated dose of the low affinity non-competitive N-methyl-D-aspartate receptor antagonist remacemide in patients who have Parkinson's disease with response fluctuations or dyskinesias, or both. A total of 33 patients were randomly assigned in a 3-to-1 ratio to receive remacemide or placebo. Remacemide was administered orally at 150 mg twice daily, increasing incrementally by 100 mg (50 mg twice daily) at 2-week intervals to a final daily regimen of 400 mg twice daily or until a maximum tolerated dose was identified. The maximum total treatment period was 12 weeks. Of the 23 patients randomly selected to receive remacemide, four completed the study at the maximum permitted dose, compared with four of the 10 patients given placebo. The median maximum tolerated dose of remacemide was 450 mg/d. There was no clinically relevant change in percentage of "on" time between baseline and maximum tolerated dose in either group. At the maximum tolerated dose of remacemide for each patient, the mean Unified Parkinson's Disease Rating Scale (UPDRS) motor examination score (part III) decreased from 33 (SD = 18) to 26 (SD = 13) compared with a decrease from 28 (SD = 12) to 27 (SD = 8) in the placebo group. There was a decrease in the mean UPDRS "complications of therapy" score (part IV) in the remacemide group from 8 (SD = 4) to 6 (SD = 4), and the placebo group remained unchanged at 6 (SD = 4). The most common adverse events associated with remacemide were nausea, vomiting, dizziness, headache, abnormal vision, and hypokinesia. Remacemide was well tolerated at a dose level of 400 mg/d. There was a trend suggesting that remacemide was effective in improving symptoms at patients' individual maximum tolerated doses. These improvements occurred without exacerbating levodopa-induced dyskinesias.

Acetamides↗

PubMed1996

The sequential administration of combined doxorubicin and paclitaxel in the treatment of advanced breast cancer.

In phase I and II studies we administered fixed doses of doxorubicin by intravenous bolus 16 hours before escalating doses of paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) for the treatment of patients with advanced breast cancer who had received no prior treatment or who had relapsed after adjuvant therapy. Nineteen patients were entered in the study from April 1994 to February 1995. The median age of participants was 54 years; the median disease-free interval was 328 days. Eleven patients had undergone prior adjuvant chemotherapy, seven had undergone prior hormonal therapy, and six had undergone chest radiotherapy. A total of 128 courses of fixed-dose doxorubicin 50 mg/m2 by intravenous bolus and paclitaxel (doses escalated from 130 to 250 mg/m2, through dose escalations of 30 mg/m2 if maximum tolerated dose was not reached) were repeated every 21 days for a median of seven cycles per patient. Toxicities encountered in this trial included grade 4 neutropenia (20% of courses) and grade 4 thrombocytopenia (3% of courses). No grade 3 or 4 nonhematologic toxicities were observed (World Health Organization grade I peripheral neuropathies and mild myalgias in 37.5% and 30% of courses, respectively). No cardiac toxicity was observed. Responses included six complete responses (31.6%), nine partial responses (47.2%), and three stable disease (15.8%), for an overall response rate of 78.8%. Median duration of overall and complete response was 8+ months and 7+ months, respectively. At dose levels > or = 190 mg/m2, all patients had achieved a response (six complete responses and six partial responses). A phase II trial using fixed doses of doxorubicin (50 mg/m2) and paclitaxel (220 mg/m2) is ongoing. Preliminary data on 71 courses report no cardiac toxicity. Treatment with paclitaxel has been well tolerated at each dose level. The maximum tolerated dose was not reached at 250 mg/m2. No cardiac toxicity was reported. The dosing sequence of doxorubicin followed by paclitaxel is a highly active regimen and needs to be tested in anthracycline patients and in an adjuvant setting.

Adult↗

PubMed2003

Phase I study of TLK286 (glutathione S-transferase P1-1 activated glutathione analogue) in advanced refractory solid malignancies.

PURPOSE: The purpose of this study was to determine the dose-limiting toxicities (DLTs), the maximum tolerated dose, and the pharmacokinetics of the novel glutathione analog TLK286 administered by i.v. infusion. EXPERIMENTAL DESIGN: Patients with advanced malignancies received i.v. TLK286 administered as a 30-min constant rate infusion once every 3 weeks in escalating doses from 60 to 1280 mg/m(2). Patients underwent tumor assessment on day 43 and continued on treatment until disease progression or unacceptable toxicity. RESULTS: A total of 35 patients were treated with 109 cycles of TLK286. At 1280 mg/m(2), 3 of 5 patients developed one of two observed dose limiting toxicities (DLTs). The DLTs were: mild pancreatitis (1 of 5) and bladder symptoms (2 of 5) consisting of hematuria, dysuria, and urinary frequency. All of the patients with DLTs continued on TLK286 treatment at 960 mg/m(2) (one dose below maximum tolerated dose) without recurrence of DLTs. DLTs were transient, resolved without sequelae, and noncumulative. TLK286-related toxicities included grade 1-2 nausea, vomiting, fatigue, transient microscopic hematuria, and anemia. Of 31 evaluable patients, 10 patients continued therapy (median six cycles; range, four to nine cycles). Pharmacokinetic studies of TLK286 on cycle 1 revealed a mean elimination half-life of 18 min (95% confidence interval, 16.1-19.9). Dose-proportional increases in both maximum blood concentrations and area under the blood-concentration-time curve were observed over the dose range of 60-960 mg/m(2). CONCLUSION: TLK286 was well tolerated in this study. TLK286 safety and pharmacokinetics support disease-specific evaluations of TLK286 at doses <1280 mg/m(2) administered once every three weeks in the treatment of patients with advanced malignancies.

Adult↗

PubMed2000

Enhancement of the anti-tumor activity of a peripheral blood progenitor cell graft by mobilization with interleukin 2 plus granulocyte colony-stimulating factor in patients with advanced breast cancer.

OBJECTIVE: Autologous interleukin 2 (IL-2)-activated natural killer (NK) cells kill a broad spectrum of tumor targets, including breast cancer. We hypothesized that mobilization with IL-2 and granulocyte colony-stimulating factor (G-CSF) for collection of peripheral blood progenitor cells (PBPC) may enhance the anti-tumor activity of the graft in autograft recipients. We determined the dose-limiting toxicity and maximum tolerated dose of subcutaneous IL-2 given with G-CSF for PBPC mobilization, the ability of IL-2 + G-CSF mobilized stem cells to reconstitute hematopoiesis, and the in vitro immunologic function of the graft in patients with advanced breast cancer. MATERIALS AID METHODS: Forty-three women with stage IIIA/B or metastatic breast cancer underwent mobilization of PBPC with IL-2 administered subcutaneously for 14 days along with G-CSF for the latter 7 days. IL-2 was given in a dose-escalated manner, with the maximum tolerated dose determined to be 1.75 x 10(6) IU/m(2)/day. Fifteen women with stage IIIA/B or metastatic breast cancer underwent G-CSF mobilization alone and served as a control group. RESULTS: [corrected] Fifty-two percent of the patients mobilized with 1L-2 at the maximum tolerated dose reached the target number of CD34(+) cells for transplantation with three aphereses compared to 93% of control patients who were mobilized with G-CSF alone. [corrected] There was no significant impact on time to engraftment of neutrophils or platelets using either mobilization regimen. The addition of subcutaneous IL-2 to mobilization increased the cytotoxicity of IL-2-activated mononuclear cells from the PBPC product against the breast cancer cell target, MCF-7, and increased the percentage of NK cells and activated T cells in the PBPC product. The enhanced NK cell number was sustained in the early posttransplant period. CONCLUSIONS: [corrected] IL-2 + G-CSF mobilization is safe, may lead to a more immunologically functional graft without impairing hematologic recovery, and thus merits further exploration to evaluate the clinical anti-tumor efficacy of these immunocompetent grafts. [corrected] Limitations of this combined approach to stem cell mobilization include a decrease in the number of CD34(+) cells mobilized with the combined cytokines and the short duration of the increased number of anti-tumor effector cells after transplant.

Adult↗

PubMed2001

Phase I study of CI-958 in children and adolescents with recurrent solid tumors.

BACKGROUND: CI-958 is a synthetic intercalating agent of a new chemical class, the benzopyranoindazoles, with promising preclinical activity. Its mechanism of action is thought to be stabilization of the cleavable complex of DNA with topoisomerase II, as well as DNA helicase blockade. It is thought to have less cardiotoxicity than the anthracyclines. Early Phase I studies in adults showed the drug to be well tolerated, making it an attractive agent to pursue in Phase I clinical trials in children. METHODS: Children and adolescents with recurrent solid tumors received CI-958 at an initial dose of 450 mg/m(2) over 2 hours. Dose escalation was performed in a standard fashion in cohorts of three patients until dose limiting toxicity and the maximum tolerated dose were determined. RESULTS: Twenty-one patients were entered on the study. The maximum tolerated dose was found to be 650 mg/m(2). Dose limiting toxicities were Grade 4 neutropenia and Grade 4 hypotension at the dose level of 700 mg/m(2). CONCLUSIONS: The maximum tolerated dose of CI-958 in children and adolescents is 650 mg/m(2). No antitumor activity has been observed.

Adolescent↗

PubMed2001

Using plasma transforming growth factor beta-1 during radiotherapy to select patients for dose escalation.

PURPOSE: The ability to prescribe treatment based on relative risks for normal tissue injury has important implications for oncologists. In non-small-cell lung cancer, increasing the dose of radiation may improve local control and survival. Changes in plasma transforming growth factor beta (TGFbeta) levels during radiotherapy (RT) may identify patients at low risk for complications in whom higher doses of radiation could be safely delivered. PATIENT AND METHODS: Patients with locally advanced or medically inoperable non-small-cell lung cancer received three-dimensional conformal RT to the primary tumor and radiographically involved nodes to a dose of 73.6 Gy (1.6 Gy twice daily). If the plasma TGFbeta level was normal after 73.6 Gy, additional twice daily RT was delivered to successively higher total doses. The maximum-tolerated dose was defined as the highest radiation dose at which < or = one grade 4 (life-threatening) late toxicity and < or = two grade 3 to 4 (severe life-threatening) late toxicities occurred. RESULTS: Thirty-eight patients were enrolled. Median follow-up was 16 months. Twenty-four patients were not eligible for radiation dose escalation beyond 73.6 Gy because of persistently abnormal TGFbeta levels. Fourteen patients whose TGFbeta levels were normal after 73.6 Gy were escalated to 80 Gy (n = 8) and 86.4 Gy (n = 6). In the 86.4-Gy group, dose-limiting toxicity was reached because there were two (33%) grade 3 late toxicities. CONCLUSION: It is feasible to use plasma TGFbeta levels to select patients for RT dose escalation for non-small-cell lung cancer. The maximum-tolerated dose using this approach is 86.4 Gy.

Adult↗

PubMed2004

Phase I dose escalation and pharmacokinetic study of pluronic polymer-bound doxorubicin (SP1049C) in patients with advanced cancer.

SP1049C is a novel anticancer agent containing doxorubicin and two nonionic pluronic block copolymers. In preclinical studies, SP1049C demonstrated increased efficacy compared to doxorubicin. The objectives of this first phase I study were to determine the toxicity profile, dose-limiting toxicity, maximum tolerated dose and pharmacokinetic profile of SP1049C, and to document any antitumour activity. The starting dose was 5 mg m(-2) (doxorubicin content) as an intravenous infusion once every 3 weeks for up to six cycles. A total of 26 patients received 78 courses at seven dose levels. The dose-limiting toxicity was myelosuppression and DLT was reached at 90 mg m(-2). The maximum tolerated dose was 70 mg m(-2) and is recommended for future trials. The pharmacokinetic profile of SP1049C showed a slower clearance than has been reported for conventional doxorubicin. Evidence of antitumour activity was seen in some patients with advanced resistant solid tumours. Phase II trials with this agent are now warranted to further define its antitumour activity and safety profile.

Adult↗

PubMed1995

Phase I study of high-dose ifosfamide, carboplatin and etoposide with autologous hematopoietic stem cell support.

More effective high-dose combination regimens are needed which have broad cytotoxic activity, steep dose-response relations and non-overlapping non-hematologic toxicities (to allow administration of full doses of each agent). This study was designed to define the dose-limiting toxicities and maximum tolerated doses of ifosfamide, carboplatin and etoposide (ICE) with hematopoietic stem cell support. Ifosfamide and carboplatin were initially fixed at 75% and 80% of the single agent maximum tolerated doses, respectively, and etoposide added to the combination. After the dose-limiting toxicity of etoposide was reached, its dose was fixed and ifosfamide and carboplatin were individually dose escalated as tolerated. All agents were given by 96h continuous infusion (days -7 to -3). Autologous marrow, with or without peripheral blood progenitor cells, was reinfused on day 0. Forty eight adults with advanced malignancies were enrolled in cohorts of three to five patients. At the maximum tolerated doses of ifosfamide 16 g/m2, carboplatin 1.8 g/m2 and etoposide 1.2 g/m2, renal toxicity precluded further dose escalation. Two patients died of organ (renal, CNS) toxicity (4%). Renal toxicity was particularly prominent in patients with prior cisplatin exposure. An early chemotherapy-stopping rule was developed, supported by pharmacologic analysis, which resulted in immediate discontinuation of ifosfamide and carboplatin if the serum creatinine, monitored twice daily during chemotherapy, exceeded 1.5 mg/dl and was > 0.5 mg/dl above baseline. High-dose ICE is well tolerated if serum creatinines are carefully monitored during chemotherapy administration. The early chemotherapy-stopping rule may enhance safety of the regimen but requires validation by addition correlation with pharmacokinetic data for each of the chemotherapeutic agents.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed2005

Phase I/II trial of paclitaxel and vinorelbine in advanced non-small cell lung cancer.

Chemotherapeutic combination regimens for advanced non-small cell lung cancer traditionally have been based on platin compounds. However, a mechanistic rationale could lead to effective non-platin combinations. Paclitaxel and vinorelbine are antimicrotubule agents with different mechanisms of action, both of which have single agent activity against non-small cell lung cancer. A Phase I/II trial of paclitaxel Day 1 and vinorelbine Days 1-3 every 21 days was, therefore, performed for patients with Stage IIIB or Stage IV non-small cell lung cancer who had not previously received chemotherapy for metastatic disease. In the Phase I investigation, up to 4 patients were treated at each dose level. The maximum tolerated dose level was found to be paclitaxel 150 mg/m2 IV Day 1 and vinorelbine 16 mg/m2 IV Days 1-3, with dose-limiting toxicities of fatigue, myalgia, and mucositis at higher doses. This dose level was then expanded with an additional 15 patients. Of the 23 patients treated for up to 10 cycles at or near the maximum tolerated dose level (19 patients with paclitaxel 150 mg/m2 IV Day 1 and vinorelbine 16 mg/m2 Days 1-3, and 4 patients with paclitaxel 150 mg/m2 IV Day 1 and vinorelbine 13 mg/m2 Days 1-3), 7 patients achieved partial response and 5 patients achieved minor response. Fatigue, myalgia, peripheral neuropathy, and transient leukopenia were the most common cumulative toxicities seen. The non-platin chemotherapy doublet of paclitaxel and vinorelbine given on this convenient 3-day schedule is worthy of further investigation in the treatment of non-small cell lung cancer.

Adult↗

PubMed1999

UFT plus calcium folinate/irinotecan in colorectal cancer.

This phase I trial combining UFT plus oral calcium folinate (Orzel) with irinotecan (CPT-11) (Camptosar) for the treatment of patients with advanced or metastatic colorectal cancer will open shortly. Eligible patients will have locally advanced or metastatic colorectal cancer, and they may have received adjuvant chemotherapy (provided it has been completed more than 6 months prior to study entry), but will have not received any chemotherapy for advanced or metastatic disease. The primary objectives of this study will be to determine the side-effect profile, dose-limiting toxicities, and the maximum tolerated dose of this combination. A recommended starting dose for future trials will be defined. Response rates will also be observed as a secondary objective. The first cohort of six patients will receive irinotecan 200 mg/m2 by intravenous infusion over 90 minutes on day 1 (the schedule that is in general use in Europe). On days 1 to 14, patients will receive UFT 250 mg/m2/d and calcium folinate 90 mg/d, both divided into three equal doses. This will be followed by a 1-week rest period with treatment for the next cycle resumed on day 22. In subsequent cohorts of six patients, UFT and irinotecan will in turn be escalated provided toxicity is acceptable. The calcium folinate dose will remain fixed at 90 mg/d throughout. The maximum tolerated dose is defined as that at which dose-limiting toxicities occur in more than one third of patients. The cohort of patients treated at the dose below the maximum tolerated dose will be expanded to a total of 20 patients to fully define the pattern of toxicities and activity of the combination.

Adolescent↗

PubMed1990

High-dose etoposide and cyclophosphamide without bone marrow transplantation for resistant hematologic malignancy.

Seventy-five patients with resistant acute leukemia or lymphoma received high-dose cyclophosphamide and etoposide to explore the activity of this combination in resistant hematologic malignancies, and to determine the maximum doses of these drugs that can be combined without bone marrow transplantation. Etoposide was administered over 29 to 69 hours by continuous infusion corresponding to total doses of 1.8 g/m2 to 4.8 g/m2. Cyclophosphamide, 50 mg/kg/d, was administered on 3 or 4 consecutive days total 150 to 200 mg/kg ideal body weight). At all dose levels myelosuppression was severe but reversible. Mucosal toxicity was dose-limiting with the maximum tolerated dose level combining etoposide 4.2 g/m2 with cyclophosphamide 200 mg/kg. Continuous etoposide infusion produced stable plasma levels that were lower than would be achieved after administration by short intravenous infusion, and this could explain our ability to escalate etoposide above the previously reported maximum tolerated dose. There were 28 complete (35%) and 12 partial (16%) responses. Median duration of complete response (CR) was 3.5 months (range 1.1 to 20+). Seventeen of 40 patients (42%) with acute myelogenous leukemia (AML) achieved CR, including 6 of 20 (30%) with high-dose cytosine arabinoside resistance. We conclude that bone marrow transplantation is not required after maximum tolerated doses of etoposide and cyclophosphamide. This regimen is active in resistant hematologic neoplasms, and the occurrence of CR in patients with high-dose cytosine arabinoside-resistant AML indicates a lack of complete cross-resistance between these regimens.

Acute Disease↗

PubMed2001

The toxicity of deglycosylated ricin A chain-containing immunotoxins in patients with non-Hodgkin's lymphoma is exacerbated by prior radiotherapy: a retrospective analysis of patients in five clinical trials.

A retrospective analysis of 102 patients with relapsed, non-Hodgkin's lymphoma treated with two different ricin A chain-containing immunotoxins (ITs) in five Phase I clinical trials indicates that the dose-limiting toxicity, vascular leak syndrome, was more frequent and more severe in patients who had undergone prior radiotherapy (RT). Excluding patients with prior RT from the calculations of the maximum tolerated dose indicates that the maximum tolerated doses of these ITs had not been reached in any trial and are clearly higher than reported previously. Excluding patients with prior RT from future clinical trials may increase the dose of ITs that can be given in the absence of severe vascular leak syndrome.

Adult↗

PubMed2002

A phase I and pharmacokinetic study of ecteinascidin-743 on a daily x 5 schedule in patients with solid malignancies.

PURPOSE: The purpose of this study was to (a) assess the feasibility of administering ecteinascidin-743 (ET-743), a novel DNA minor-groove disrupting agent of marine origin, administered as a daily i.v. infusion for 5 days every 3 weeks; (b) recommend a dose for Phase II studies; (c) characterize its pharmacokinetic behavior; and (d) seek preliminary evidence of anticancer activity. EXPERIMENTAL DESIGN: Patients with advanced solid malignancies were treated with escalating doses of ET-743 as a daily 1-h i.v. infusion for 5 days every 3 weeks. Plasma and urine were sampled on both days 1 and 5 of the first course. Pharmacokinetic parameters were related to the principal toxicities. RESULTS: Forty-two patients were treated with 118 courses of ET-743 at doses ranging from 6 to 380 microg/m(2)/day. Elevations in hepatic transaminases were common at ET-743 dose levels > or =216 microg/m(2)/day, resolved rapidly, and were never dose limiting nor cumulative. Instead, hematological toxicity was the principal toxicity that precluded dose escalation. The maximum tolerated dose of ET-743 that could be administered repetitively was 325 microg/m(2)/day. Antitumor activity was noted in three patients with leiomyosarcoma and primary peritoneal and ovarian carcinomas. The pharmacokinetics of ET-743 were dose independent, and drug accumulation over the 5 days of treatment was modest, with the ratio of the area under the plasma-versus-time curve on day 5 to that on day 1 averaging 2.05. The volume of distribution at steady state was large (mean, 1037 liters/m(2)), and the mean terminal half life on day 5 was 26.81 h. CONCLUSIONS: The maximum tolerated dose of ET-743 that can be administered repetitively is 325 microg/m(2)/day daily x 5 every 3 weeks, which is recommended for disease-directed clinical trials. The acceptable toxicity profile of ET-743 on the divided-dose schedule evaluated in this trial, as well as the generally superior antitumor activity associated with divided-dose schedules in preclinical studies, provides a rationale for further evaluation of ET-743 on this administration schedule.

Adult↗

PubMed2001

Phase I and pharmacokinetic study of ecteinascidin 743 administered as a 72-hour continuous intravenous infusion in patients with solid malignancies.

Ecteinascidin 743 (ET-743) is a cytotoxic tetrahydroisoquinoline alkaloid that covalently binds to DNA in the minor groove. The in vitro chemosensitivity of cancer cells to ET-743 is markedly enhanced by prolonging the duration of exposure to the drug. A Phase I study of ET-743 given as a 72-h continuous i.v. infusion every 21 days was performed. Characteristics of the 21 adult patients with refractory solid tumors enrolled in the study were as follows: (a) 12 men; (b) 9 women; (c) median age, 59 years; (d) Eastern Cooperative Oncology Group performance status < or = 1, 20 patients; and (e) two prior regimens of chemotherapy, 7 patients. Dose limiting toxicity (DLT) was defined by typical criteria, except that grade 3 transaminitis did not constitute a DLT. There were no DLTs in the six patients evaluated at the first two dose levels of 600 and 900 microg/m2. Reversible grade 4 transaminitis occurred in two of nine patients after treatment with the first cycle of therapy at the third dose level of 1200 microg/m2. Another patient experienced grade 4 rhabdomyolysis, renal failure requiring hemodialysis, grade 4 neutropenia, and grade 3 thrombocytopenia during the second cycle of therapy with this dose. The maximum tolerated dose was 1200 microg/m2, and an additional six patients were enrolled at an intermediate dose level of 1050 microg/m2. This well-tolerated dose was established as the recommended Phase II dose. The disposition of ET-743 was distinctly biexponential, and a departure from linear pharmacokinetic behavior was evident at the 1200-microg/m2 dose level. Pharmacokinetic parameters determined at 1050 microg/m2 were (mean +/- SD): maximum plasma concentration, 318 +/- 147 pg/ml; initial disposition phase half-life, 9.0 +/- 10.3 min; terminal phase half-life, 69.0 +/- 56.7 h; and total plasma clearance, 28.4 +/- 22.5 liters/h/m2. Prolonged systemic exposure to concentrations of the agent that are cytotoxic in vitro were achieved. Toxicity of the drug is clearly schedule-dependent, because increasing the duration of infusion from 3 or 24 h to 72 h results in decreased myelosuppression and comparable hepatotoxicity. Although there were no objective responses to therapy, clear evidence of antitumor activity was observed in a patient with epithelioid mesothelioma, as confirmed by positron emission tomography studies. A Phase II trial to assess the efficacy of ET-743 against this highly refractory neoplasm has been initiated on the basis of this observation. The therapeutically optimal administration schedule remains to be established, inasmuch as there have been indications of activity against a variety of tumors during Phase I studies when the drug was infused over times ranging from 1 to 72 h. Characterizing the pharmacokinetics of ET-743 during the course of Phase II trials and Phase I combination studies is recommended to assure that this promising new anticancer drug can be used with an acceptable margin of safety.

Adult↗

PubMed2004

Effects of drug loading on the antitumor activity of a monoclonal antibody drug conjugate.

PURPOSE: An antibody-drug conjugate consisting of monomethyl auristatin E (MMAE) conjugated to the anti-CD30 monoclonal antibody (mAb) cAC10, with eight drug moieties per mAb, was previously shown to have potent cytotoxic activity against CD30(+) malignant cells. To determine the effect of drug loading on antibody-drug conjugate therapeutic potential, we assessed cAC10 antibody-drug conjugates containing different drug-mAb ratios in vitro and in vivo. EXPERIMENTAL DESIGN: Coupling MMAE to the cysteines that comprise the interchain disulfides of cAC10 created an antibody-drug conjugate population, which was purified using hydrophobic interaction chromatography to yield antibody-drug conjugates with two, four, and eight drugs per antibody (E2, E4, and E8, respectively). Antibody-drug conjugate potency was tested in vitro against CD30(+) lines followed by in vivo xenograft models. The maximum-tolerated dose and pharmacokinetic profiles of the antibody-drug conjugates were investigated in mice. RESULTS: Although antibody-drug conjugate potency in vitro was directly dependent on drug loading (IC(50) values E8<E4<E2), the in vivo antitumor activity of E4 was comparable with E8 at equal mAb doses, although the E4 contained half the amount of MMAE per mAb. E2 was also an active antitumor agent but required higher doses. The maximum-tolerated dose of E2 in mice was at least double that of E4, which in turn was twice that of E8. MMAE loading affected plasma clearance, as E8 cleared 3-fold faster than E4 and 5-fold faster than E2. CONCLUSIONS: By decreasing drug loading per antibody, the therapeutic index was increased demonstrating that drug loading is a key design parameter for antibody-drug conjugates.

Animals↗

PubMed2002

Phase I study of irinotecan in pediatric patients with malignant solid tumors.

PURPOSE: To determine the dose-limiting toxicity, maximum tolerated dose, and potential efficacy of irinotecan in children with refractory malignant solid tumors. PATIENTS AND METHODS: In the present phase I clinical trial, 28 patients received irinotecan 50 to 200 mg/m2 per day by intravenous 2-hour infusion over the course of 3 days, repeated once after an interval of 25 days. Fifty-one treatment courses were administered to these patients. RESULTS: Dose-limiting toxicities were observed at the dose of 200 mg/m2 per day for 3 days. Diarrhea and hematopoietic toxicities were the dose-limiting factors, and the former required support with intravenous fluid administration. The occurrence of vomiting was variable. Decreases in clinical tumor marker levels were observed in the majority of patients who received two cycles of irinotecan 80 mg/m2 per day to 200 mg/m2 per day over the course of 3 days, and partial response was attained in four patients who received irinotecan in two cycles of 140 mg/m2 per day to 200 mg/m2 per day over the course of 3 days. Pharmacokinetic studies showed that the plasma concentration of irinotecan and its active metabolite SN-38 ranged from 93 to 2,820 ng/mL and 5.2 to 34.8 ng/mL, respectively, during 3-day infusions of irinotecan 200 mg/m2 per day. The mean clearance of irinotecan was 14.54 L/h per m2 (range 8.45-20.83 L/h per m2). CONCLUSION: The maximum tolerated dose was determined to be a dose of irinotecan between 160 mg/m2 per day and 180 mg/m2 per day administered over the course of 3 consecutive days on an inpatient basis, repeated once after 25 days off, and our results indicate that irinotecan is a promising anticancer agent that is worthy of phase II trials in pediatric solid tumors.

Adolescent↗

PubMed1997

Review of docetaxel/doxorubicin combination in metastatic breast cancer.

Docetaxel (Taxotere) and doxorubicin (Adriamycin) have each demonstrated significant activity in metastatic breast cancer. Thus, the combination of docetaxel and doxorubicin has been evaluated in phase I trials to establish the dose-limiting toxicity, maximum tolerated dose, recommended dose for future phase II and III studies, and toxicity profile of the two agents used in combination. Results from phase I trials in patients with metastatic breast cancer indicate that the docetaxel/doxorubicin combination is well tolerated. The recommended dose for the combination regimen is either 50 mg/m2 of doxorubicin followed by 75 mg/m2 of docetaxel or 60 mg/m2 of both drugs, without granulocyte colony-stimulating factor (G-CSF) support. Febrile neutropenia complicated by grade 3 infection was the dose-limiting effect at the maximum tolerated dose. The response rate at this dose level was 90%. Based on the preliminary results of phase I studies, further phase II and III studies of a docetaxel/doxorubicin combination regimen are warranted.

Adult↗