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Purpose: Endostatin is the first endogenous angiogenesis inhibitor to enter clinical trials. Laboratory investigations with endostatin have indicated broad antitumor activity coupled with remarkably low toxicity. A phase I trial of recombinant human endostatin was designed to evaluate toxicity and explore biologic effectiveness in patients with refractory solid tumors., Patients and Methods: Endostatin was administered as a 1-hour intravenous infusion given daily for a 28-day cycle. A starting dose of 30 mg/m2 was explored with subsequent dose escalations of 60, 100, 150, 225, and 300 mg/m2. Assessment of serum pharmacokinetics was performed on all 21 patients. Western blot assay and mass spectroscopy were employed to evaluate endostatin metabolism. Circulating levels of endogenous proangiogenic growth factors were examined. Tumor and tumor blood supply were imaged by dynamic computed tomography (CT), magnetic resonance imaging, ultrasound, and positron emission tomography., Results: Endostatin given on this schedule was essentially free of significant drug-related toxicity. Two transient episodes of grade 1 rash were observed. No clinical responses were observed. Endostatin pharmacokinetics were linear with dose, and serum concentrations were achieved that are associated with antitumor activity in preclinical models. No aggregate effect on circulating proangiogenic growth factors were seen, although several patients exhibited persistent declines in vascular endothelial growth factor levels while enrolled in the study. A few patients demonstrated changes in their dynamic CT scans suggestive of a decline in microvessel density, although overall, no consistent effect of endostatin on tumor vasculature was seen., Conclusion: Endostatin given daily as a 1-hour intravenous infusion was well tolerated without dose-limiting toxicity at doses up to 300 mg/m2.

Purpose: To evaluate the biologic interactions and toxicities of carboplatin combined with a 24-hour infusion of thymidine 75 mg/m(2) in a phase I trial., Patients and Methods: Thirty-two patients with cancer refractory to conventional therapy were treated. The first set of patients (n = 7) received thymidine alone 4 weeks before subsequent planned courses of thymidine combined with carboplatin followed (4 weeks) by carboplatin alone. Carboplatin was administered over 20 minutes at hour 20 of the 24-hour thymidine infusion. The carboplatin dose was escalated in patient groups: 200 mg/m(2) (n = 3); 300 mg/m(2) (n = 7); 350 mg/m(2) (n = 4); 400 mg/m(2) (n = 3); 480 mg/m(2) (n = 10); and 576 mg/m(2) (n = 5). At the maximum-tolerated dose (480 mg/m(2)), five patients received combined therapy first and carboplatin alone second, and five patients received carboplatin first and combined therapy second. Maintenance therapy for stable or responding patients was combined therapy., Results: Evaluation demonstrated a trend toward thymidine protection of carboplatin-induced treatment-limiting thrombocytopenia. Neutropenia with carboplatin alone or in combination was negligible. Thymidine alone had no myelosuppressive effects and produced reversible grade 1 or 2 nausea and vomiting (57%), headache (25%), and grade 1 neurotoxicity (22%). Thymidine did not enhance expected carboplatin toxicities. There was no therapy-related infection or bleeding. Analysis of platinum in plasma ultrafiltrate and urine showed no effect by thymidine. Similarly, thymidine pharmacokinetics was not affected by carboplatin. As predicted, nicotinamide adenine dinucleotide levels in peripheral lymphocytes were increased during exposure to carboplatin and/or thymidine but were decreased by carboplatin alone. In three patients with high-grade glioma, responses included one complete remission (21 months) and one partial remission (14 months) at the 480-mg/m(2)-dose level, and disease stabilization (7 months) at the 400-mg/m(2-dose) level. A minor response was observed in a patient with metastatic colon cancer (5 months) at the 480-mg/m(2)-dose level., Conclusion: The combination of carboplatin and thymidine as described is well tolerated. The data presented have resulted in a phase II study by the North American Brain Tumor Consortium.

Purpose: A novel phase I trial design was used to determine the maximum-tolerated dose (MTD) and pharmacokinetics for penclomedine when administered as an intravenous (i.v.) infusion over 1 hour daily for 5 days, repeated every 28 days. This study also tests the feasibility of a novel two-stage design for phase I trials., Patients and Methods: Twenty-eight patients with advanced malignancy who met standard eligibility criteria were treated with i.v. penclomedine. The initial daily dose was 50 mg/m2. Dose escalations were planned using a modified Fibonacci sequence. One patient was enrolled on each dose level during the first stage of this trial. In the second stage, patients were enrolled in cohorts of three, proceeding in an up-and-down manner based on toxicities observed. MTD was determined by logistic regression analysis. Pharmacokinetic assessment was performed during the first cycle of treatment., Results: Dose-limiting toxicities (DLT) observed during this trial were principally neurologic and were self-limited. Although hematologic toxicity was rare, the few patients with significant hematologic changes experienced late nadirs with prolonged time to recovery. The MTD was estimated as 381 mg/m2 (80% CI, 343 to 415 mg/m2). Although there was a long elimination half-life, accumulation of penclomedine over the 5 days of administration was negligible., Conclusion: The novel trial design used in this study was safe and appeared effective in limiting the numbers of patients treated at lower-dose levels. Reversible neurotoxicity was dose-limiting. Although the estimated MTD was 381 mg/m2, any dose within the CI would be reasonable for phase II study.

Purpose: We conducted a phase I trial of carboxyamidotriazole (CAI, NSC 609974), designed to determine the maximum-tolerated dose (MTD), toxicity profile, and pharmacokinetic characteristics of CAI gelatin capsule (gelcap) formulation administered daily as a single oral dose., Patients and Methods: Twenty-nine patients with advanced malignancy who met standard eligibility criteria were treated with once-daily CAI given in cycles of 28 days. Pharmacokinetic sampling was performed on days 1 and 29 and trough plasma CAI levels were assessed weekly., Results: Patients were entered at dose levels of 50, 75, and 100 mg/m2. All three patients at the 100-mg/m2 level experienced dose-limiting neurocerebellar toxicity. Other neurotoxicities were mild. Gastrointestinal side effects were common, but generally mild, with 23 patients experiencing nausea and/or vomiting of any grade. Fatigue was a frequent complaint, with 19 patients experiencing mild to moderate symptoms. Six patients with nausea and vomiting and five with fatigue experienced relief of symptoms with a change to nocturnal administration of CAI. Peak plasma concentrations (Cp) occurred at 2.4 +/- 1.5 hours after administration of the oral gelcap dose. Patients approached steady-state trough plasma concentrations (Css) by days 8 to 15 and maintained a relatively constant Css throughout the course of treatment. For all patients, the mean variation in weekly CAI Cp was 12.4% +/- 5.3%., Conclusion: The MTD for the gelcap formulation was 75 mg/m2 with dose-limiting neurocerebellar toxicity (ataxia) seen at 100 mg/m2. Other prominent side effects, including nausea, vomiting, and fatigue, were partially alleviated through altering the administration schedule to nighttime dosing.

Purpose: To evaluate the biologic interactions and toxicities of melphalan (L-PAM) combined with 41.8 degrees C whole-body hyperthermia (WBH) for 60 minutes., Patients and Methods: Sixteen patients with refractory cancer were treated (May 1992 to May 1995) with WBH alone during week 1) thereafter patients were randomized to receive either L-PAM alone on week 2 and L-PAM plus WBH on week 5, or the reverse sequence. Patients who demonstrated clinical improvement received WBH plus L-PAM monthly. Dose levels of L-PAM were 10 mg/m2 (n = 3), 15 mg/m2 (n = 3), 17.5 mg/m2 (n = 6), and 20 mg/m2 (n = 4). L-PAM was administered at target temperature; WBH was administered with an Aquatherm radiant-heat device (patent pending; Cancer Research Institute, New York, NY)., Results: Comparisons of mean WBC count and platelet nadirs for L-PAM alone and L-PAM plus WBH demonstrated that the addition of WBH resulted in nadir counts that were, on average, 25% lower. There were no instances of febrile neutropenia or bleeding. Toxicities allowed for escalation of L-PAM to 20 mg/m2; all four patients at this level experienced grade 4 myelosuppression. No significant myelosuppression was observed at 10 and 15 mg/m2. Grade 3 myelosuppression was observed in two of six patients at 17.5 mg/m2. Responses included complete remission (CR) of pancreatic cancer (10 mg/m2), partial remission (PR) of malignant melanoma in two patients (20 mg/m2), and transient clinical and/or serologic improvement in five patients. The pharmacokinetics of L-PAM were not altered by WBH. Observed cytokine induction by WBH is also discussed in detail., Conclusion: We conclude that L-PAM with 41.8 degrees C WBH is well tolerated. Clinical results are consistent with preclinical predictions and provide a foundation for second-generation trials now in progress.

Purpose: A phase I dose-escalation trial of intravenous (IV) L-buthionine-SR-sulfoximine (BSO) with melphalan (L-PAM) was performed to determine the toxicity and biologic activity of BSO, administered as a short infusion every 12 hours, and the combination of BSO plus L-PAM., Patients and Methods: Twenty-eight patients with refractory malignancies received 30-minute infusions of BSO every 12 hours for 6 to 10 doses in week 1 followed in week 2 by either IV L-PAM (15 mg/m2) alone or BSO as in week 1 with L-PAM. Patients received the combination in week 5 (course no. 2) if they received L-PAM alone during week 2 and vice versa. BSO doses ranged from 1.5 g/m2 to 13.104 g/m2., Results: The only toxicity observed with BSO infusions was occasional nausea/vomiting. Evaluation of 23 paired courses (L-PAM plus BSO v L-PAM) showed significantly (P < .001) greater leukopenia and thrombocytopenia with L-PAM plus BSO. No other significant toxicity was noted. Measurement of intracellular glutathione (GSH) levels in peripheral mononuclear cells (PBLs) of all patients receiving BSO showed a consistent, non-dose-dependent, linear decrease in GSH with repeated BSO doses. Maximal GSH depletion (40% of baseline values, absolute values 200 to 250 ng/10(6) PBLs) was noted after the sixth BSO dose; extended BSO dosing schedules beyond six total BSO doses did not further deplete GSH. Evaluation of gamma-glutamylcysteine synthetase (GCS) activity showed marked inhibition near the end of each infusion with near complete recovery of GCS activity before the next BSO dose. The pattern of GCS inhibition mirrored the plasma BSO concentrations with peak values (level 6, 4 to 8 mmol/L L,R+L,S BSO) observed at the end of the infusion with a rapid decrease in plasma concentrations with an estimated half-life (t1/2) of less than 2 hours. Differential elimination of the R+S stereoisomers was observed. Analysis of L-PAM pharmacokinetics showed marked interpatient variability and a significant decrease in total-body clearance (P = .01) and volume of distribution (P = .03) in courses with L-PAM plus BSO as compared with L-PAM alone., Conclusion: This study shows that BSO alone and in combination with L-PAM can be safely given to patients, but that a schedule of short infusions every 12 hours does not result in GSH depletion less than 30% of baseline values.

Purpose: To evaluate the biologic interactions and toxicities of carboplatin combined with 41.8 degrees C whole-body hyperthermia (WBH) for 60 minutes in a phase I clinical trial., Patients and Methods: Thirty assessable patients with cancer refractory to conventional therapy were treated. During induction therapy, patients received WBH alone in week 1, WBH plus carboplatin in week 2, and carboplatin alone in week 5. Carboplatin dose was escalated (three patients per group) as follows: 100, 150, 200, 250, 300, 350, 400, 480, and 575 mg/m2; three additional patients were entered at 480 mg/m2. Carboplatin was administered at target temperature., Results: Comparisons of the mean/median WBC and platelet nadirs for carboplatin alone and carboplatin plus WBH demonstrated no enhancing effect by WBH. Toxicities including nausea and/or vomiting, as well as myelosuppression, were within acceptable limits, allowing for escalation to a dose of 575 mg/m2; three of three patients at this dose level experienced grade 4 myelosuppression with no associated infection or bleeding. No renal toxicity was observed. Analysis of platinum in plasma ultrafiltrate and urine showed only slight effects of WBH on the pharmacokinetics and renal excretion of platinum. Responses included the following: lung--minor response (200 mg/m2); gastrointestinal neuroendocrine--complete response (CR) (400 mg/m2); pancreatic--partial response (PR) (480 mg/m2); small bowel--PR (575 mg/m2); ovarian--CR, two patients (575 mg/m2), with marker data suggesting WBH enhancement of carboplatin cytotoxicity. Another three patients experienced clinical improvement after WBH plus carboplatin, but progression with carboplatin alone (lung, 400 mg/m2; gastrointestinal neuroendocrine, 480 mg/m2; melanoma, 480 mg/m2)., Conclusion: We conclude that carboplatin with WBH is well tolerated even at conventional carboplatin doses. Clinical results are consistent with preclinical predictions of an increased therapeutic index for this combination, which encourages future clinical studies.