Cantuzumab mertansine in a three-times a week schedule: a phase I and pharmacokinetic study.

PURPOSE: Cantuzumab mertansine (SB-408075; huC242-DM1) is a conjugate of the maytansinoid drug DM1 to the antibody huC242, which targets CanAg antigen. In previous studies, cantuzumab mertansine was considered safe and tolerable, but transaminitis precluded tolerance of higher doses. Based on those studies, it was suggested that treatment at intervals of the half-life of the intact immunoconjugate may allow a higher dose density. This provided the rationale for the three-times weekly treatment explored in this protocol. METHODS: Patients with advanced solid tumors and documented CanAg expression were treated with escalating doses of cantuzumab mertansine IV administered three-times a week in a 3 out of 4 weeks schedule. Plasma samples were assayed to determine pharmacokinetic parameters. RESULTS: Twenty patients (pts) with colon (11/20), rectal carcinomas (2/20), or other malignancies (7/20) were treated with doses ranging from 30 to 60 mg/m2 per day of cantuzumab mertansine IV three-times a week. The maximum tolerated dose (MTD) was 45 mg/m2, and the dose-limiting toxicity was grade 3 transaminitis. Hepatic, hematologic, and neurosensory effects occurred, but were rarely severe with repetitive treatment at doses of 45 mg/m2. CONCLUSIONS: Treatment with cantuzumab mertansine at 45 mg/m2 per day three-times weekly x 3-every-4-week schedule proved that a dose-intense treatment with an immunoconjugate can be safely administered. The pharmacokinetic profile of the intact immunoconjugate indicates that the linker is cleaved with a half-life of about 2 days, resulting in faster clearance of the maytansinoid relative to the antibody. Therefore, with the development of second-generation immunoconjugates, there is a need for improvement of the immunoconjugate linker to take full advantage of the slow clearance of full-length antibody molecules.

A phase I and pharmacokinetic study of pemetrexed plus irinotecan in patients with advanced solid malignancies.

PURPOSE: The main objectives of this phase I and pharmacokinetic, open-label study were to characterize the principal toxicities and determine the maximum tolerated dose of the multitargeted antifolate pemetrexed administered in combination with irinotecan. The study also sought to detect major pharmacokinetic drug-drug interactions between these agents and preliminary evidence of antitumor activity in patients with advanced solid malignancies. EXPERIMENTAL DESIGN: Pemetrexed was administered as a 10-min i.v. infusion followed by irinotecan given i.v. over 90 min every 3 weeks to patients with advanced solid malignancies. The study objectives were first pursued in heavily pretreated patients and then in lightly pretreated patients who also received vitamin supplementation. RESULTS: Twenty-three heavily pretreated patients enrolled in the first stage of the study, and the maximum tolerated dose level of pemetrexed/irinotecan without vitamin supplementation was 400/250 mg/m(2); further dose escalation was precluded by severe neutropenia that was protracted and/or associated with fever. In the second stage of the study, 28 lightly pretreated patients were administered pemetrexed/irinotecan with vitamin supplementation; these patients tolerated pemetrexed/irinotecan at a dose level of 500/350 mg/m(2), which reflected clinically relevant single-agent doses of both agents. No major pharmacokinetic interactions between the agents were evident. Four patients, two patients each with colorectal cancer refractory to fluoropyrimidines and advanced mesothelioma, had partial responses. CONCLUSIONS: The pemetrexed/irinotecan regimen is well tolerated in patients with advanced solid malignancies at clinically relevant single-agent doses. The recommended dose level of pemetrexed/irinotecan for subsequent disease-directed evaluations involving lightly pretreated patients is 500/350 mg/m(2) every 3 weeks with vitamin supplementation.

A phase II, pharmacokinetic, and biologic study of semaxanib and thalidomide in patients with metastatic melanoma.

PURPOSE: This phase II study evaluated the combination of semaxanib, a small molecule tyrosine kinase inhibitor of vascular endothelial growth factor (VEGF) receptor-2, and thalidomide in patients with metastatic melanoma to assess the efficacy, tolerability, pharmacokinetic (PK) and pharmacodynamic (PD) characteristics of the combination. PATIENTS AND METHODS: Patients with metastatic melanoma, who had failed at least one prior biologic and/or chemotherapeutic regimen, were treated with escalating doses of thalidomide combined with a fixed dose of semaxanib. RESULTS: Twelve patients were enrolled and received 44 courses of semaxanib at the fixed dose of 145 mg/m2 intravenously twice-weekly in combination with thalidomide, commencing at 200 mg daily with intrapatient dose escalation as tolerated. Treatment with semaxanib was initiated 1 day before thalidomide in the first course, permitting the assessment of the PKs of semaxanib alone (course 1) and in combination with thalidomide (course 2). The principal toxicities included deep venous thrombosis, headache, and lower extremity edema. Of ten patients evaluable for response, one complete response lasting 20 months and one partial response lasting 12 months were observed. Additionally, four patients had stable disease lasting from 2 to 10 months. The PKs of semaxanib were characterized by drug exposure parameters comparable to those observed in single-agent phase II studies, indicating the absence of major drug-drug interactions. Maximum semaximib plasma concentration values were 1.2-3.8 microg/ml in course 1 and 1.1-3.9 microg/ml in course 2. The mean terminal half-life was 1.3 ( +/- 0.31) h. Biological studies revealed increasing serum VEGF concentrations following treatment in patients remaining on study for more than 4 months. CONCLUSION: The combination of semaxanib and thalidomide was feasible and demonstrated anti-tumor activity in patients with metastatic melanoma who had failed prior therapy. Further evaluations of therapeutic strategies that target multiple angiogenesis pathways may be warranted in patients with advanced melanoma and other malignancies.

Phase I and pharmacokinetic study of tasidotin hydrochloride (ILX651), a third-generation dolastatin-15 analogue, administered weekly for 3 weeks every 28 days in patients with advanced solid tumors.

PURPOSE: To determine the safety, tolerability, and pharmacokinetics and to seek preliminary evidence of anticancer activity of tasidotin (ILX651), a novel dolastatin analogue, when administered as a 30-minute i.v. infusion weekly for 3 weeks every 4 weeks. EXPERIMENTAL DESIGN: Thirty patients with advanced solid malignancies were treated with 82 courses at six dose levels ranging from 7.8 to 62.2 mg/m2 weekly, initially according to an accelerated dose-escalation scheme, which evolved into a Fibonacci scheme as a relevant degree of toxicity was observed. Plasma and urine were sampled to characterize the pharmacokinetic behavior of tasidotin. RESULTS: A high incidence of neutropenia complicated by fever (one patient), or precluding treatment on day 15 (three patients), was the principal toxicity of tasidotin, at doses above 46.8 mg/m2. At all dose levels, nonhematologic toxicities were generally mild to moderate and manageable. Grade 3 toxicities included diarrhea and vomiting (one patient each). Drug-induced neurosensory symptoms were mild and there was no evidence of cardiovascular toxicity, which has been previously associated with other dolastatins. Tasidotin pharmacokinetics were mildly nonlinear, whereas metabolite kinetics were linear. A patient with non-small cell lung carcinoma experienced a minor response, and a patient with hepatocellular carcinoma had stable disease lasting 11 months. CONCLUSIONS: The recommended dose for phase II studies of tasidotin administered on this schedule is 46.8 mg/m2. The mild myelosuppression and manageable nonhematologic toxicities at the recommended dose, the evidence of antitumor activity, and the unique mechanistic aspects of tasidotin warrant further disease-directed evaluations on this and alternative schedules.

Phase I, pharmacokinetic, and biological study of erlotinib in combination with paclitaxel and carboplatin in patients with advanced solid tumors.

PURPOSE: To assess the feasibility of administering erlotinib, an inhibitor of epidermal growth factor receptor (EGFR) tyrosine kinase, in combination with paclitaxel and carboplatin, and to identify pharmacokinetic interactions, evaluate downstream effects of EGFR inhibition on surrogate tissues, and seek preliminary evidence for clinical activity. EXPERIMENTAL DESIGN: Patients with advanced solid malignancies were treated continuously with erlotinib at doses of 100, 125, and 150 mg/d orally along with fixed i.v. doses of paclitaxel 225 mg/m(2) and carboplatin AUC 6 mg x min/mL, both on day 1 every 3 weeks. RESULTS: Twenty evaluable patients were treated with 136 courses of erlotinib, paclitaxel, and carboplatin. Myelosuppression, skin rash, and diarrhea were the principal toxicities. Dose limiting diarrhea occurred in 1 of 6 patients at the 100 mg erlotinib dose level, whereas 0 of 9 evaluable patients at the 125 mg erlotinib dose level experienced dose limiting toxicity and 3 of 5 evaluable patients at 150 mg erlotinib experienced dose limiting skin rash and neutropenic sepsis. There was no evidence of pharmacokinetic interactions between paclitaxel and erlotinib; however, total carboplatin exposure trended higher in the presence of erlotinib. No consistent downstream effects on EGFR inhibition were found in skin. Durable objective responses were observed in non-small-cell lung and head and neck cancers. CONCLUSIONS: A dose level of erlotinib 125 mg combined with paclitaxel 225 mg/m(2) and carboplatin AUC 6 mg.min/mL is recommended for disease-directed studies. This phase I trial was followed by a randomized phase III study in non-small-cell lung cancer using a similar regimen.

Phase 1 and pharmacokinetic study of intravenous irinotecan in refractory solid tumor patients with hepatic dysfunction.

PURPOSE: To determine the recommended starting doses and pharmacokinetics of irinotecan in cancer patients with impaired liver function treated on a weekly schedule. EXPERIMENTAL DESIGN: Patients with solid tumors who had impaired liver function were enrolled into four groups based on baseline serum total bilirubin and aspartate aminotransferase (AST)/alanine aminotransferase (ALT): Group 1 (n = 19): total bilirubin 1.5 to 3.0 x institutional upper limit of normal (IULN) and ALT/AST

A phase I study of the dolastatin-15 analogue tasidotin (ILX651) administered intravenously daily for 5 consecutive days every 3 weeks in patients with advanced solid tumors.

PURPOSE: To determine the maximum tolerated dose, dose-limiting toxicity, and pharmacokinetics of the dolastatin-15 analogue, tasidotin (ILX651), when administered i.v. daily for 5 days every 3 weeks. EXPERIMENTAL DESIGN: Thirty-six patients with advanced solid tumors received a total of 114 courses through eight dose levels ranging from 2.3 to 36.3 mg/m(2). Pharmacokinetic samples were collected in cycle 1. RESULTS: Neutropenia was the principal dose-limiting toxicity at 36.3 mg/m(2)/d along with grade 3 ileus and elevated aspartate amino transaminase/alanine amino transaminase (n = 1). At the maximum tolerated dose, 27.3 mg/m(2), 4 of 14 patients experienced dose-limiting grade 4 neutropenia. The other principal toxicities consisted of mild-to-moderate elevated transaminases, alopecia, fatigue, and nausea. One patient with melanoma metastatic to liver and bone treated at 15.4 mg/m(2)/d experienced a complete response and received 20 courses of tasidotin. Two other patients with melanoma had mixed responses of cutaneous metastases at 27.3 mg/m(2)/d associated with either stable or progressive visceral disease. In addition, nine patients had stable disease. There was no accumulation of tasidotin following repeated daily dosing. Tasidotin decayed from plasma in a biphasic fashion with a half-life of <45 minutes in most cases. CONCLUSION: The maximum tolerated dose and recommended phase II dose for tasidotin when administered on this schedule was 27.3 mg/m(2)/d. The favorable toxicity profile of tasidotin compared with other antitubulin agents (particularly the lack of severe cumulative neuropathy, peripheral edema, and fatigue), the observed antitumor activity of tasidotin, and its novel mechanism of action support further disease-directed evaluations of this agent on this 5-day schedule every 3 weeks.

Phase I and pharmacokinetic study of sequences of the rebeccamycin analogue NSC 655649 and cisplatin in patients with advanced solid tumors.

PURPOSE: To evaluate the feasibility of administering NSC 655649, a water-soluble rebeccamycin analogue that inhibits both topoisomerases I and II, in combination with cisplatin (CDDP) in adults with solid malignancies. Major toxicologic and pharmacologic differences between the two sequences of drug administration were also assessed. EXPERIMENTAL DESIGN: NSC 655649 was administered as a 60-minute i.v. infusion; CDDP was given i.v. before or after NSC 655649 on day 1. Each patient was treated with alternating drug sequences every 3 weeks; doses of each drug were escalated in separate cohorts of new patients. Sequential dose escalation of NSC 655649 or CDDP resulted in three dosage permutations of NSC 655649/CDDP: 440/50, 550/50, and 440/75 mg/m2. After the maximum tolerated dose level was determined, the feasibility of using granulocyte colony-stimulating factor to permit further dose escalation was explored. RESULTS: Twenty patients were treated with 70 courses of NSC 655649/CDDP. Myelosuppression was the principal toxicity. The incidence of severe neutropenia, often associated with severe thrombocytopenia, was unacceptably high in minimally pretreated patients at the NSC 655649/CDDP dose level of 550/50 mg/m2 without and with granulocyte colony-stimulating factor. Major pharmacokinetic interactions between NSC 655649 and CDDP were not apparent. No relevant sequence-dependent differences in toxicity or pharmacokinetic variables occurred. Three patients had partial responses. CONCLUSIONS: NSC 655649 and CDDP were well tolerated by minimally pretreated subjects at 440 and 50 mg/m2, respectively. Neither pharmacokinetic interactions between the agents nor sequence-dependent toxicologic or pharmacokinetic effects were apparent. The tolerance and preliminary activity observed with this combination suggest that disease-directed evaluations of the regimen are warranted.

Phase I and pharmacokinetic study of the dolastatin-15 analogue tasidotin (ILX651) administered intravenously on days 1, 3, and 5 every 3 weeks in patients with advanced solid tumors.

PURPOSE: To determine the maximum tolerated dose (MTD), dose-limiting toxicity (DLT), and pharmacokinetics of tasidotin (ILX651), a dolastatin-15 analogue, when administered on days 1, 3, and 5 every 3 weeks in patients with advanced solid tumors. PATIENTS AND METHODS: Thirty-two patients were treated with 92 courses of tasidotin through seven dose levels determined by a modified Fibonacci scheme ranging from 3.9 to 45.7 mg/m(2). Pharmacokinetic samples were collected during the first course. RESULTS: Neutropenia was the principal DLT at the 45.7 mg/m(2)/d dose level. In addition, one patient also experienced grade 3 neutropenia complicated with grade 3 esophageal candidiasis and grade 3 dehydration. Only 1 of 11 patients treated at the MTD, 34.4 mg/m(2), experienced dose-limiting neutropenia. Other common, drug-related toxicities included mild to moderate fatigue, anemia, nausea, anorexia, emesis, alopecia, and diarrhea. The best observed antitumor response consisted of stable disease and was noted in 10 patients (31%); the median duration on study for those patients with stable disease was 99.5 days compared with 37.5 days for those patients with progressive disease. Tasidotin plasma concentrations declined biphasically with an effective half-life of < or =55 minutes, and approximately 11% was excreted unchanged in the urine. CONCLUSION: The recommended dose for phase II studies and the MTD when tasidotin is administered on days 1, 3, and 5 every 3 weeks is 34.4 mg/m(2). The favorable toxicity profile of tasidotin compared with other antitubulin agents, including other dolastatin analogues, and its novel mechanism of action support further disease-directed evaluation of this agent.

Determinants of tumor response and survival with erlotinib in patients with non--small-cell lung cancer.

PURPOSE: Erlotinib is a highly specific epidermal growth factor receptor (HER1/EGFR) tyrosine kinase inhibitor. This phase II study of erlotinib in patients with HER1/EGFR-expressing non-small-cell lung cancer previously treated with platinum-based chemotherapy evaluated tumor response, survival, and symptom improvement. PATIENTS AND METHODS: Fifty-seven patients received an oral, continuous daily dose of 150 mg of erlotinib. Assessments of objective response used WHO and Response Evaluation Criteria in Solid Tumors criteria. The European Organization for Research and Treatment of Cancer Quality of Life Questionnaire C30, supplemented with a lung cancer module, Quality of Life Questionnaire LC13, was used to measure health-related quality of life. Additional analyses were performed to identify predictors of response and survival. RESULTS: The objective response rate was 12.3% (95% CI, 5.1% to 23.7%). Responses were observed regardless of type or number of prior chemotherapy regimens. Median survival time was 8.4 months (95% CI, 4.8 to 13.9 months), and the 1-year survival rate was 40% (95% CI, 28% to 54%). Erlotinib therapy was associated with tumor-related symptom improvement. The drug was well tolerated; drug-related cutaneous rash and diarrhea were observed in 75% and 56% of patients, respectively. One patient experienced toxicity consisting of severe grade 3 rash and diarrhea. Time since diagnosis and good performance status were significant predictors of survival in a multivariate Cox proportional hazards model, whereas HER1/EGFR staining intensity was not. Additionally, survival correlated with the occurrence and severity of rash. CONCLUSION: Erlotinib was active and well tolerated in this patient population, and further clinical development is clearly warranted. Cutaneous rash seems to be a surrogate marker of clinical benefit, but this finding should be confirmed in ongoing and future studies.

Troxacitabine, an L-stereoisomeric nucleoside analog, on a five-times-daily schedule: a phase I and pharmacokinetic study in patients with advanced solid malignancies.

PURPOSE: To assess the feasibility of administering troxacitabine, a unique L-nucleoside that is not a substrate for deoxycytidine deaminase-mediated catabolism, as a 30-minute intravenous (IV) infusion daily for 5 days. PATIENTS AND METHODS: Patients with advanced solid malignancies were treated with escalating doses of troxacitabine as a 30-minute IV infusion daily for 5 days. Plasma and urine sampling was performed to characterize the pharmacokinetics and pharmacodynamics of troxacitabine. RESULTS: Thirty-nine patients received 124 courses of troxacitabine at eight dose levels ranging from 0.12 to 1.8 mg/m(2)/d. Severe neutropenia that was protracted (> 5 days) and/or associated with fever, and skin rashes were consistently experienced by heavily (HP) and minimally pretreated (MP) patients at doses exceeding 1.2 and 1.5 mg/m(2)/d, respectively. At troxacitabine doses > or = 1.2 mg/m(2)/d, treatment was often delayed 1 additional week for complete resolution of hematologic effects, resulting in lengthening of the treatment interval from every 3 to 4 weeks. Skin rash, palmar-plantar erythrodysesthesia, and thrombocytopenia were also observed and were occasionally severe, particularly at the highest doses. A patient with metastatic ocular melanoma experienced a partial response. Pharmacokinetics of troxacitabine were dose-independent; mean (SD) values for the volume of distribution at steady-state and clearance (Cl(s)) were 60 (32) L and 161 (33) mL/min, respectively, on day 1. After treatment on the fifth day, terminal half-life values averaged 39 (63) hours, and Cl(s) was reduced by approximately 20%, averaging 127 (27) mL/min. The principal mode of drug elimination was renal. CONCLUSION: Recommended doses for phase II studies of troxacitabine as a 30-minute infusion daily for 5 days every 4 weeks are 1.5 and 1.2 mg/m(2)/d for MP and HP patients, respectively. Broad disease-directed evaluations of troxacitabine on this schedule and possibly less frequent schedules are warranted.

ZD1839, a selective oral epidermal growth factor receptor-tyrosine kinase inhibitor, is well tolerated and active in patients with solid, malignant tumors: results of a phase I trial.

PURPOSE: To investigate the tolerability, pharmacokinetics, and antitumor activity of the oral, selective epidermal growth factor receptor-tyrosine kinase inhibitor ZD1839 in patients with solid malignant tumors. PATIENTS AND METHODS: This was an open, phase I, escalating multiple-dose tolerability and pharmacokinetic trial. ZD1839 was administered once daily for 14 consecutive days followed by 14 days off treatment. Dose escalation started at 50 mg/d and continued to 925 mg or until consistent dose-limiting toxicity (DLT) was observed. RESULTS: Sixty-four patients were entered at eight dose levels. The most frequent dose-related grade 1 and 2 adverse events were an acne-like (or folliculitis) rash, nausea, and diarrhea. Three of nine patients treated at 700 mg/d developed DLT (reversible grade 3 diarrhea); grade 3 and 4 events were uncommon. Exposure to ZD1839 was dose proportional, and the mean terminal half-life was 48 hours (range, 37 to 65). Four of 16 patients with non-small-cell lung cancer (NSCLC) had objective partial responses observed from ZD1839 300 to 700 mg/d. Overall, 16 patients remained on study for > or = 3 months, with seven of these patients (five with NSCLC, including three of the patients with partial response) remaining on study for > or = 6 months. CONCLUSION: ZD1839 was well tolerated, with DLT observed at a dose well above that at which antitumor activity was seen. Pharmacokinetic analysis confirmed that ZD1839 was suitable for administration as a once-daily oral tablet formulation. Phase II monotherapy and phase III combination trials in NSCLC are being conducted to investigate further the efficacy, tolerability, and optimal daily dose of ZD1839.

A phase I and pharmacokinetic study of pegylated camptothecin as a 1-hour infusion every 3 weeks in patients with advanced solid malignancies.

PURPOSE: To assess the feasibility of administering camptothecin (CPT), the prototypic topoisomerase I inhibitor, as polyethylene glycol (PEG)-CPT, a macromolecule consisting of CPT conjugated to chemically modified PEG. The study also sought to determine the maximum-tolerated dose (MTD) of PEG-CPT, 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 PEG-CPT as a 1-hour intravenous (IV) infusion every 3 weeks. A modified continual reassessment method was used for dose-level assignment to determine the MTD, which was defined as the highest dose level at which the incidence of dose-limiting toxicity did not exceed 20%. RESULTS: Thirty-seven patients were treated with 144 courses of PEG-CPT at seven dose levels ranging from 600 to 8,750 mg/m(2). Severe myelosuppression was consistently experienced by heavily pretreated (HP) and minimally pretreated (MP) patients at the highest dose level evaluated, 8,750 mg/m(2), whereas both HP and MP patients tolerated repetitive treatment at 7,000 mg/m(2). Cystitis, nausea, vomiting, and diarrhea were also observed but were rarely severe. A partial response was noted in a patient with platinum- and etoposide-resistant small-cell lung carcinoma, and minor responses were noted in one patient each with adenocarcinoma of unknown primary type and osteosarcoma. The pharmacokinetics of free CPT were dose proportional. Free CPT accumulated slowly in plasma, with maximal plasma concentrations achieved at 23 +/- 12.3 hours; the harmonic mean half-life (t(1/2)) of free CPT was long (t(1/2), 77.46 +/- 36.77 hours). CONCLUSION: Clinically relevant doses of CPT can be delivered by administering PEG-CPT. The recommended dose for phase II studies in both MP and HP patients is 7,000 mg/m(2) as 1-hour IV every 3 weeks. The characteristics of the myelosuppressive effects of PEG-CPT, the paucity of severe nonhematologic toxicities with repetitive treatment, the preliminary antitumor activity noted, and the slow clearance of CPT enabling simulation of desirable pharmacokinetic parameters with a convenient single-dosing regimen warrant further disease-directed evaluations.

Cantuzumab mertansine, a maytansinoid immunoconjugate directed to the CanAg antigen: a phase I, pharmacokinetic, and biologic correlative study.

PURPOSE: To determine the maximum tolerated dose and pharmacokinetics of cantuzumab mertansine, an immunoconjugate of the potent maytansine derivative (DM1) and the humanized monoclonal antibody (huC242) directed to CanAg, intravenously (i.v.) once every 3 weeks and to seek evidence of antitumor activity. PATIENTS AND METHODS: Patients with CanAg-expressing solid malignancies were treated with escalating doses of cantuzumab mertansine administered i.v. every 3 weeks. The pharmacokinetic parameters of cantuzumab mertansine, the presence of plasma-shed CanAg, and the development of both human antihuman and human anti-DM1 conjugate antibodies also were characterized. RESULTS: Thirty-seven patients received 110 courses of cantuzumab mertansine at doses ranging from 22 to 295 mg/m2. Acute, transient, and reversible elevations of hepatic transaminases were the principal toxic effects. Nausea, vomiting, fatigue, and diarrhea were common but rarely severe at the highest dose levels. Dose, peak concentration, and area under the concentration-time curve correlated with the severity of transaminase elevation. The mean (+/- SD) clearance and terminal elimination half-life values for cantuzumab mertansine averaged 39.5 (+/-13.1) mL/h/m2 and 41.1 (+/-16.1) hours, respectively. Strong expression (3+) of CanAg was documented in 68% of patients. Two patients with chemotherapy-refractory colorectal carcinoma had minor regressions, and four patients had persistently stable disease for more than six courses. CONCLUSION: The recommended dose for cantuzumab mertansine is 235 mg/m2 i.v. every 3 weeks. The absence of severe hematologic toxic effects, preliminary evidence of cantuzumab mertansine tumor localization, and encouraging biologic activity in chemotherapy-refractory patients warrant further broad clinical development of this immunoconjugate in CanAg-expressing tumors.

Pharmacodynamic evaluation of the epidermal growth factor receptor inhibitor OSI-774 in human epidermis of cancer patients.

BACKGROUND: OSI-774 is an inhibitor of the epidermal growth factor receptor tyrosine kinase (EGFR-TK) currently in clinical development. In preclinical models, the antitumor activity of OSI-774 was directly related to its ability to inhibit the EGFR-TK. On the basis of these data, we hypothesized that inhibition of the EGFR-TK will be required for this agent to be effective in the clinic. This study evaluated the pharmacodynamic effects of OSI-774 in normal skin tissues collected from patients treated with the agent in a Phase I study. METHODS: Patients with advanced cancer who were treated in a Phase I study of OSI-774 underwent a biopsy of normal skin epidermis at baseline and after the last dose of drug in the first course of treatment. The expression and activation of the EGFR, downstream signaling extracytoplasmatic-regulated kinase (Erk), and cell cycle regulator p27 were determined in paraffin-embedded skin tissues using an immunohistochemical method (IHC). The IHC data were analyzed using both a semiquantitative scoring system and an automatic absorbance quantitative IHC method. The number of cells with nuclear staining of p27 per 500 cells was determined. Plasma samples were collected to quantitate OSI-774 plasma concentrations. RESULTS: A total of 56 skin specimens was collected from 28 patients treated with OSI-774 at doses ranging from 25 to 200 mg/day. There was a significant decrease in phospho-EGFR (Tyr 1173) expression as determined semiquantitatively with OSI-774 treatment [2.75 +/- 0.51 (mean +/- SD) pretreatment versus 2.36 +/- 0.76 after treatment, pair comparison P = 0.01]. The quantitative ratio [(phopho-EGFR/EGFR) x 100] of phospho-EGFR (Tyr1173) decreased from 64.16 +/- 36.58 pretreatment to 48.87 +/- 35.37 post-treatment (pair comparison, P = 0.02). No significant differences were observed in phospho-Erk (Thr202/Tyr204) expression. The mean number of cells with nuclear staining for p27 increased from 185 +/- 101 (mean +/- SD) pretreatment to 253 +/- 111 post-treatment (pair comparison P = 0.02). A total of 12 (42.8%), 7 (25%), and 14 (50%) patients had >25% variation in the ratio of phospho-EGFR (Tyr1173), phospho-Erk (Thr202/Tyr204), and p27 expression, respectively. Only changes in p27 expression were related to the administered dose of OSI-774. CONCLUSIONS: OSI-774 exerted pharmacodynamic effects in skin tissues of 30-50% of patients treated with the agent. Up-regulation of p27, which is a downstream effect of EGFR inhibition, was dose related. Although there was a significant decrement in phospho-EGFR (Tyr1173), it was not related to the administered dose of OSI-774. On the basis of these findings and the relatively simple and reliable method to measure p27 expression, this biomarker appears to be the most promising and is being evaluated in Phase II studies as a predictor of clinical outcome.

A phase I and pharmacokinetic study of Col-3 (Metastat), an oral tetracycline derivative with potent matrix metalloproteinase and antitumor properties.

PURPOSE: The purpose of this research was to assess the feasibility of administering Col-3, an oral chemically modified tetracycline derivative with potent inhibitory effects on matrix metalloproteinase activity and production, and recommend a dose on an uninterrupted once-daily schedule. The study also sought to characterize the pharmacokinetic behavior of Col-3 and seek evidence of anticancer activity. EXPERIMENTAL DESIGN: Patients with advanced solid malignancies were treated with escalating doses of Col-3 with dose level assignment according to an accelerated titration scheme. Because photosensitivity skin reactions were being reported in concurrent trials of Col-3, patients were instructed to apply sunscreen rigorously throughout the trial. The maximum tolerated dose was defined as the highest dose at which <2 of the first 6 new patients experienced dose-limiting toxicity. The pharmacokinetic behavior of Col-3 was characterized, and pharmacodynamic relationships were sought. RESULTS: Thirty-three patients were treated with 73 courses of Col-3 at four dose levels ranging from 36 to 98 mg/m2/day. Unacceptably high incidences of photosensitivity skin reactions and malaise were noted in the first 28-day courses of patients treated with Col-3 at doses exceeding 50 mg/m2/day. At 50 mg/m2/day, severe toxicity occurred in 2 of 12 new patients in first courses, and no additional dose-limiting toxicities were observed in subsequent courses. Other mild to modest adverse effects included nausea, vomiting, liver function tests abnormalities, diarrhea, mucositis, leukopenia, and thrombocytopenia. The pharmacokinetics of Col-3 were dose proportional, and mean trough concentrations at steady state were similar to biologically relevant concentrations in preclinical studies. Major responses did not occur, but durable disease stability was noted in 3 patients, one each with carcinosarcoma of the uterus, pancreas, and ovary, all of whom had experienced disease progression before Col-3 treatment. CONCLUSIONS: The recommended dose for Phase II studies of Col-3 administered once daily on an uninterrupted schedule is 50 mg/m2/day accompanied by efforts that promote adherence to the use of sunscreen and other photoprotective measures. Pharmacokinetic results indicate that plasma concentrations above biologically relevant concentrations are readily maintained at this dose, and additional disease-directed studies, particularly in patients with soft tissue sarcoma, should be considered.

A phase I/IIA trial of continuous five-day infusion of squalamine lactate (MSI-1256F) plus carboplatin and paclitaxel in patients with advanced non-small cell lung cancer.

PURPOSE: Squalamine is an antitumor agent that has been shown to have antiangiogenic activity in animal models. This Phase I/IIA study was designed to assess the safety, clinical response, and pharmacokinetics of squalamine when administered as a 5-day continuous infusion in conjunction with standard chemotherapy every 3 weeks in patients with stage IIIB (pleural effusion) or stage IV non-small cell lung cancer. EXPERIMENTAL DESIGN: Patients with chemotherapy-naive non-small cell lung cancer were treated with escalating doses of squalamine in combination with standard doses of paclitaxel and carboplatin. Paclitaxel and carboplatin were administered on day 1, followed by squalamine as a continuous infusion on days 1-5, every 21 days. RESULTS: A total of 45 patients were enrolled (18 patients in the Phase I dose escalation arm and 27 in the Phase IIA arm). The starting dose of squalamine was 100 mg/m(2)/day and escalated to 400 mg/m(2)/day; two of three patients at 400 mg/m(2)/day had dose-limiting toxicity that included grade 3/4 arthralgia, myalgia, and neutropenia. On the basis of safety and toxicity, 300 mg/m(2)/day was selected as the Phase II dose of squalamine in this combination regimen. An additional 27 patients (a total of 33) were enrolled according to the protocol treatment schema at 300 mg/m(2)/day. There was no pharmacokinetic evidence of drug interactions for the combination of squalamine, carboplatin, and paclitaxel. Forty-three patients were evaluable for response. Partial tumor responses were observed in 12 (28%) of these patients; an additional 8 evaluable patients (19%) were reported to have stable disease. For all of the patients treated, the median survival was 10.0 months; and 1-year survival was 40%. CONCLUSIONS: The combination of squalamine given continuously daily for 5 days, with paclitaxel and carboplatin given on day 1, is well tolerated. Patient survival data and the safety profile of this drug combination suggests that the use of squalamine given at its maximum tolerated dose with cytotoxic chemotherapy should be explored further as a potentially effective therapeutic strategy for patients with stage IIIB or IV non-small cell lung cancer.

A randomized phase I and pharmacological trial of sequences of 1,3-bis(2-chloroethyl)-1-nitrosourea and temozolomide in patients with advanced solid neoplasms.

PURPOSE: O(6)-alkylguanine-DNA alkyltransferase (AGAT) is modulated by methylating agents, which, in turn, abrogates nitrosourea resistance in preclinical studies. The feasibility of administering various sequences of 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) and temozolomide (TEM) in patients with advanced solid neoplasms was evaluated in this Phase I and pharmacological study to assess this premise in the clinical setting. The study also sought to determine the maximum tolerated dose (MTD) levels of BCNU and TEM as a function of Seq, to characterize the pharmacokinetic (PK) behavior of TEM administered both before and after BCNU, assess AGAT fluctuations in peripheral blood mononuclear cells (PBMCs), and seek preliminary evidence of anticancer activity. EXPERIMENTAL DESIGN: Sixty-three patients were randomized to receive treatment with oral TEM daily on days 1-5 and BCNU administered i.v., either on day 1 before TEM [Sequence (Seq) B-->T] or day 5 after TEM (Seq T-->B). Treatment was repeated every 6 weeks. Blood sampling for PK studies was performed on both days 1 and 5 of course one. PBMCs were sampled to evaluate major sequence-dependent effects on AGAT levels. RESULTS: Neutropenia and thrombocytopenia were the principal dose-limiting toxicities of the BCNU/TEM regimen. These effects were more prominent in patients receiving Seq T-->B, resulting in a much lower MTD of 80/100 mg/m(2)/day compared with 150/110 mg/m(2)/day for Seq B-->T. Notable antitumor activity was observed in patients with glioblastoma multiforme, sarcoma, and ovarian carcinoma. No sequence-dependent PK effects were noted to account for sequence-dependent toxicological effects. At the MTD level, AGAT activity in PBMCs decreased 3-fold, on average, and AGAT fluctuations did not appear to be sequence-dependent. CONCLUSIONS: The principal toxicities of the BCNU/TEM regimen were neutropenia and thrombocytopenia, which were consistent and predictable, albeit sequence-dependent. Seq T-->B was substantially more myelosuppressive, resulting in disparate MTDs and dose levels recommended for subsequent disease-directed evaluations (150/110 and 80/100 mg/m(2)/day for Seq B-->T and T-->B, respectively). Sequence-dependent differences in TEM PK do not account for this clinically relevant magnitude of sequence-dependent toxicity. The characteristics of the myelosuppressive effects of BCNU/TEM, the paucity of severe nonhematological toxicities, and antitumor activity at tolerable doses warrant disease-directed evaluations on this schedule.

Administration of CI-1033, an irreversible pan-erbB tyrosine kinase inhibitor, is feasible on a 7-day on, 7-day off schedule: a phase I pharmacokinetic and food effect study.

PURPOSE: To determine the maximum tolerated dose of administrating CI-1033, an oral 4-anilinoquinazoline that irreversibly inhibits the tyrosine kinase domain of all erbB subfamilies, on an intermittent schedule, and assess the interaction of CI-1033 with food on the pharmacokinetic behavior. EXPERIMENTAL DESIGN: Escalating doses of CI-1033 from a dose level of 300 mg/day for 7 days every other week were administered to patients with advanced solid malignancies. Plasma concentration-time data sets from all evaluable patients were used to develop a population pharmacokinetic model. Noncompartmental methods were used to independently assess the effect of a high-fat meal on CI-1033 absorption and bioavailability. RESULTS: Twenty-four patients were treated with 69 twenty-eight day courses. The incidence of unacceptable toxicity, principally diarrhea and skin rash, was observed at the 300 mg/day dose level. At the 250 mg/day level, toxicity was manageable, and protracted administration was feasible. A one-compartment linear model with first-order absorption and elimination adequately described the pharmacokinetic disposition. CL/F, apparent volume of distribution (Vd/F), and ka (mean +/- relative SD) were 280 L/hour +/- 33%, 684 L +/- 20%, and 0.35 hour(-1)+/- 69%, respectively. Cmax values were achieved in 2 to 4 hours. Systemic CI-1033 exposure was largely unaffected by administration of a high-fat meal. At 250 mg, concentration values exceeded IC50 values required for prolonged pan-erbB tyrosine kinase inhibition in preclinical assays. CONCLUSIONS: The recommended dose on this schedule is 250 mg/day. Its tolerability and the biological relevance of concentrations achieved at the maximal tolerated dose warrant consideration of disease-directed evaluations. This intermittent treatment schedule can be used without regard to meals.

A Phase I and pharmocokinetic study of exatecan mesylate administered as a protracted 21-day infusion in patients with advanced solid malignancies.

PURPOSE: The purpose of this study was to assess the feasibility of administering exatecan, a water-soluble, potent camptothecin analogue, as a protracted 21-day continuous i.v. infusion (CIVI). The study also sought to determine the maximum tolerated dose (MTD) of exatecan on a 21-day CIVI schedule, characterize its pharmacokinetic behavior, and seek preliminary evidence of anticancer activity. EXPERIMENTAL DESIGN: Exatecan dose-schedule development was performed in two stages using the modified Continual Reassessment Method and single patient cohorts. First, patients with advanced solid malignancies were treated with exatecan (0.15 mg/m(2)/day) as a CIVI for 5 days, and the duration of the CIVI was incrementally increased from 5 to 21 days. In the second stage of the study, the dose was incrementally increased to derive a tolerable dose of exatecan administered as 21-day CIVI. The MTD was defined for both minimally pretreated (MP) and heavily pretreated (HP) patients as the highest dose level at which the incidence of dose-limiting toxicity does not exceed 20%. RESULTS: Thirty-one patients were treated with 100 courses of exatecan at 6 dose-schedule levels. The incidence of the principal dose-limiting toxicities, neutropenia and thrombocytopenia, was unacceptably high at exatecan doses exceeding 0.15 mg/m(2)/day as a 21-day CIVI, which was determined to be the MTD for both MP and HP patients. The pharmacokinetics of exatecan were dose-proportional, and mean [coefficient of variation (percentage) steady-state concentration (plasma concentration at steady-state)] values ranged from 6.88 (80.6) to 19.41 (74.2) ng/ml at exatecan dose levels ranging from 0.15 to 0.30 mg/m(2)/day, which are similar to IC(50) values against human tumor cell lines treated for shorter periods. Mean pharamacokinetic parameters for total exatecan derived from a compartmental model included clearance and volume of distribution values of 1.39 (86.9) liters/h/m(2) and 39.66 (197.4) liters, respectively. Two HP patients with non-small cell lung and unknown primary carcinomas had partial responses, and objective evidence of anticancer activity and clinical benefit were noted in several other individuals. CONCLUSIONS: The administration of exatecan as a 21-day CIVI at doses as high as 0.15 mg/m(2)/day is safe and feasible for both MP and HP patients. The characteristics of the myelosuppressive effects of exatecan on this schedule, the paucity of severe nonhematological toxicities, and documented anticancer activity in several drug-refractory malignancies warrant further evaluation of the merits of administering exatecan by either a CIVI or alternate drug delivery systems to achieve protracted systemic exposure.