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Purpose: To assess the feasibility of administering ZD9331, a thymidylate synthase (TS) inhibitor that does not undergo polyglutamation and has broad antitumor activity, in combination with docetaxel in patients with advanced solid malignancies. The study also sought to determine the principal toxicities of the regimen and recommend appropriate doses for phase II studies, characterize the pharmacokinetics of the agents, evaluate the possibility of major drug-drug interactions, and seek preliminary evidence of anti-cancer activity., Patients and Methods: Patients with advanced solid malignancies were treated with escalating doses of docetaxel as a 60-minute intravenous (IV) infusion followed 30 minutes later by ZD9331 as a 30-minute IV infusion every 3 weeks. At least three patients were treated at each dose level, and the maximum tolerated dose level was defined as the highest dose level that was not associated with an unacceptably high incidence of severe toxicity. The pharmacokinetics of both ZD9331 and docetaxel were also characterized., Results: Nineteen patients were treated with 71 cycles of ZD9331 and docetaxel (ZD9331/docetaxel) at dose levels that encompassed dosing iterations of ZD9331 ranging from 65 to 260 mg/m(2) and docetaxel doses in the range of 50 to 75 mg/m(2). Neutropenia was the principal toxicity of the ZD9331/docetaxel regimen. Since five of six patients treated at the ZD9331/docetaxel dose-level of 260/60 mg/m(2) had grade 4 neutropenia that was brief and uncomplicated in the first course, a rigorous exploration of higher dose levels was not undertaken. Nonhematologic toxicities, consisting of malaise, diarrhea, rash, nausea, and vomiting, were also observed, but these effects were rarely severe. No major antitumor responses were observed. The pharmacokinetics of both ZD9331 and docetaxel were similar to those reported in previous studies of each agent administered alone, suggesting the lack of major drug-drug interactions., Conclusion: The combination regimen, consisting of ZD9331 and docetaxel, is feasible and well tolerated at single-agent doses that are clinically-relevant. This ZD9331/docetaxel regimen does not appear to be associated with either major pharmacokinetic or toxicologic drug-drug interactions. A ZD9331/docetaxel dose level of 260/60 mg/m(2) is recommended as an initial dose level in disease-directed studies of the regimen, with further dose escalation of docetaxel to 75 mg/m(2) if the initial treatment is well tolerated. Further studies with this regimen are warranted in tumor types that have demonstrated sensitivity to both agents.

Purpose: To determine the antitumor activity of ABX-EGF, a fully human monoclonal antibody to the epidermal growth factor receptor (EGFr), in previously treated patients with metastatic renal cell carcinoma, and to characterize its toxicity, immunogenicity, pharmacokinetics, and pharmacodynamics., Patients and Methods: The antitumor activity, as well as the toxicity, pharmacokinetics, pharmacodynamics, and immunogenicity of ABX-EGF, were assessed., Results: Eighty-eight patients were treated with ABX-EGF doses of 1.0, 1.5, 2.0, or 2.5 mg/kg weekly with no loading dose. EGFr immunostaining was performed on 76 tumor biopsy specimens (86%), and 69 (91%) scored positive. Major responses occurred in three patients, and two patients had minor responses. Forty-four patients (50%) also had stable disease at their first 8-week assessment, and the median progression-free survival (PFS) was 100 days (95% CI, 58 to 140 days). Low hemoglobin and high alkaline phosphatase predicted for short PFS. The principal toxicity, an acneiform rash, occurred in 68%, 95%, 87%, and 100% of patients who received at least three doses of ABX-EGF at 1.0, 1.5, 2.0, and 2.5 mg/kg/wk, respectively. A trend indicated that the severity of the rash may relate to PFS. No human antihuman antibodies were detected. ABX-EGF pharmacokinetics fit a model that incorporated both linear and saturable EGFr-mediated clearance mechanisms, and interindividual variability was low. At 2.5 mg/kg/wk, ABX-EGF concentrations throughout treatment exceeded those estimated to saturate nonlinear clearance and inhibit xenograft growth by 90%., Conclusion: ABX-EGF was generally well tolerated. The objective response rate was low in previously treated patients with metastatic renal cell carcinoma. Although skin rash may be a pharmacodynamic marker of drug action, its potential as a surrogate marker of clinical benefit requires further evaluation.

Purpose: The purpose of this study was to assess the feasibility and characterize the pharmacokinetics of squalamine administered as a continuous i.v. infusion daily for 5 days every 3 weeks., Experimental Design: Patients with advanced solid malignancies were treated with escalating doses of squalamine as a 5-day continuous i.v. infusion every 3 weeks. Doses were initially escalated in 100% increments from a starting dose of 6 mg/m(2)/day, with a single patient treated at each dose level until moderate toxicity was observed, at which time additional patients were treated., Results: Thirty-three patients were treated with 73 courses of squalamine at 13 dose levels ranging from 6 to 700 mg/m(2)/day. Hepatotoxicity, characterized by brief, asymptomatic elevations in transaminases and hyperbilirubinemia, was the principal dose-limiting toxicity of squalamine. At 700 mg/m(2)/day, two of three patients developed grade 4 hyperbilirubinemia, which precluded further dose escalation. At 500 mg/m(2)/day, one of seven patients experienced dose-limiting grade 4 hyperbilirubinemia and grade 3 neurosensory changes, which resolved soon after treatment. Squalamine pharmacokinetics were dose-proportional. At 500 mg/m(2)/day, the mean (percentage coefficient of variation) clearance, half-life, and volume of distribution of squalamine were 2.67 liters/h/m(2) (85%), 9.46 h (81%), and 36.84 liters/m(2) (124%), respectively, and steady-state concentrations [20.08 micro g/ml (13%)] were well above those that inhibit angiogenesis in preclinical models., Conclusions: At the recommended Phase II dose of 500 mg/m(2)/day, squalamine is well tolerated and results in plasma concentrations at least an order of magnitude higher than those required for prominent antiangiogenic effects in preclinical studies.

Background: The aim of this study was to assess the feasibility of administering bizelesin, a cyclopropylpyrroloindole with extraordinarily high potency as a bifunctional DNA-damaging agent and selectivity for specific AT-rich DNA sequences, as a single i.v. bolus injection every 4 weeks in patients with advanced solid malignancies. The study also sought to determine the maximum tolerated dose (MTD) of bizelesin, characterize its pharmacokinetic behavior, and seek preliminary evidence of anticancer activity., Patients and Methods: Patients with advanced solid malignancies were treated with escalating doses of bizelesin as an i.v. bolus injection every 4 weeks. The selection of the specific starting dose, 0.1 micro g/m(2), which was equivalent to one-tenth the toxic dose low in dogs, factored in large interspecies differences in myelotoxicity as gauged using an ex vivo hematopoietic colony-forming assay. Due to concerns about the high potency of bizelesin and the large interspecies differences in toxicity, a conservative dose-escalation scheme was used for dose-level assignment to determine the MTD levels for both minimally pretreated (MP) and heavily pretreated (HP) patients. A variety of analytical assays were assessed to reliably measure bizelesin concentrations in plasma., Results: Sixty-two patients were treated with 185 courses of bizelesin at eight dose levels ranging from 0.1 to 1.5 micro g/m(2). Myelosuppression, principally neutropenia that was always brief, was the most common toxicity observed. Thrombocytopenia and anemia were uncommon and severe non-hematological effects were not observed. Severe neutropenia alone and/or associated with fever was consistently experienced by HP and MP patients at doses exceeding 0.71 and 1.26 micro g/m(2), respectively. These doses also resulted in functionally non-cumulative myelosuppression as repetitive treatment was well-tolerated. A 40% reduction in measurable disease lasting 24 months was noted in a patient with advanced ovarian carcinoma. Various analytical methods were evaluated but none demonstrated the requisite sensitivity to reliably quantify the minute plasma concentrations of bizelesin and metabolites resulting from administering microgram quantities of drug., Conclusions: The highly potent and unique cytotoxic agent, bizelesin can be feasibly administered to patients with advanced solid malignancies. The recommended doses for phase II studies of bizelesin as a bolus i.v. injection every 4 weeks are 0.71 and 1.26 micro g/m(2) in HP and MP patients, respectively. The characteristics of the myelosuppression, the paucity of severe toxicities with repetitive treatment, the preliminary antitumor activity noted, and, above all, its unique mechanism of action as a selective DNA-damaging agent and high potency, warrant disease-directed evaluations of bizelesin in solid and hematopoietic malignancies and consideration of its use as a cytotoxic in targeted conjugated therapeutics.

The immunologic response of graft recipients to antilymphocyte globulin has been studied. The clearance from the serum of (125)I-labeled antilymphocyte globulin was studied in 15 graft recipients previously treated with antilymphocyte globulin and in 4 control patients not previously treated with antilymphocyte globulin. The mean serum half-life of antilymphocyte globulin was 7.2 days in control patients, 3.8 days in 13 renal graft recipients, and 22 hr in 2 heart graft recipients. All but one of the antilymphocyte globulin-treated patients had rapid clearance. Patients treated with equine antilymphocyte globulin had rapid clearance of rabbit and goat antilymphocyte globulin as well as horse antilymphocyte globulin. All patients with rapid clearance of antilymphocyte globulin had circulating antibodies to xenogeneic gamma globulin. Two patients with rapid clearance of antilymphocyte globulin had circulating complexes of antilymphocyte globulin. Five renal graft recipients were treated with aggregate-free equine gamma globulin before antilymphocyte globulin therapy in an attempt to induce tolerance to xenogeneic gamma globulin. In these five patients neither rapid clearance of antilymphocyte globulin nor significant titers of circulating antibody to xenogeneic gamma globulin developed. The induction of tolerance to xenogenic gamma globulin may benefit patients treated with antilymphocyte globulin.

Schwartz, Gabriel H. (National Institute of Arthritis and Metabolic Diseases, Bethesda, Md.), Donald Eiler, and Milton Kern. Solubilization of the conjugation inhibitor from Escherichia coli cell wall. J. Bacteriol. 89:89-94. 1965.-Conjugation between F(-) and HfrC strains of Escherichia coli is inhibited by the presence of cell wall derived from either strain. The inhibitor can be solubilized from such cell walls or whole cells by treatment with periodate. The soluble material is relatively acid-labile and alkali-stable, nondialyzable, nonsedimentable at 100,000 x g (1 hr), partially sedimented after 3 hr at 100,000 x g, sensitive to small changes in ionic strength, neutralized by cationic reagents, and is insensitive to proteinases, nucleases, lipases, and carbohydrases. The soluble inhibitor derived from male and female cells is indistinguishable by all the criteria tested.