Phase I study of the taxane BMS-188797 in combination with carboplatin administered every 3 weeks in patients with solid malignancies.

RATIONALE: BMS-188797 is one of several novel taxanes in ongoing clinical development. It has superior activity in experimental tumor models when compared with paclitaxel. BMS-188797 has a single C-4 modification, a 4-desacetyl-4-methylcarbonate, compared with paclitaxel. METHODS: We did a phase I study, in which a fixed dose of carboplatin was combined with a dose escalation schedule of BMS-188797, both administered once every 3 weeks, in patients with advanced solid malignancies. RESULTS: Thirty patients were treated, 11 at the proposed recommended phase II dose. The dose-limiting toxicity was myelosuppression. There was a linear relationship between administered dose of BMS-188797 and the measured area under the curve (AUC). There was significant interpatient variability of BMS-188797 AUC at the maximum tolerated dose. Two radiographic partial responses were observed: one patient with duodenal adenocarcinoma and one patient with esophageal adenocarcinoma (time on study, 19 and 30 weeks, respectively). CONCLUSION: The recommended phase II dose for BMS-188797 and carboplatin administered on a once-every-3 week schedule is carboplatin AUC = 5 mg min/mL and BMS-188797 at a dose of 135 mg/m(2).

Phase I clinical trial of BMS-247550, a derivative of epothilone B, using accelerated titration 2B design.

PURPOSE: BMS-247550 is a semisynthetic derivative of epothilone B with mechanism of action analogous to paclitaxel. It has shown impressive antitumor activity in preclinical studies including in taxane-resistant models. We conducted a phase I trial, based on accelerated titration "2B" design, of BMS-247550 given as a 1-hour infusion every 3 weeks. EXPERIMENTAL DESIGN: Seventeen patients (M:F, 10:7; median age, 54 years; performance status, 0-2) were treated on the trial. Forty-five cycles (1-9 cycles) of BMS-247550 were given at dosages ranging from 7.4 to 56 mg/m2. All patients received prophylaxis for hypersensitivity reactions, related to Cremophor-EL, with steroids and histamine antagonists. RESULTS: First-course dose-limiting toxicity (DLT) was observed in two of three patients at 56 mg/m2 (neutropenic sepsis, prolonged grade 4 neutropenia) and in one of six patients at 40 mg/m2. Nonhematologic grade 3 to 4 toxicities observed were emesis and fatigue and they occurred only at 56 mg/m2. Grade 1 to 2 peripheral neuropathy was also observed. Other grade 1 to 2 toxicities were myalgias, arthralgias, rash, hand/foot syndrome, and mucositis. AUC and C(max) seemed proportional to the dose and the DLT. Development of neutropenia with BMS-247550 is related to the duration of drug exposure above a threshold. CONCLUSIONS: The maximum tolerated dose (MTD) of BMS-247550 is 40 mg/m2 given every 3 weeks. Neutropenia is the DLT. The accelerated titration "2B" design may help in determining MTD with fewer patients enrolled and more being treated closer to the MTD. However, the accelerated titration design did not seem to shorten the study duration.

Phase I study of a novel taxane BMS-188797 in adult patients with solid malignancies.

PURPOSE: Preclinical studies show that BMS-188797 has a broad spectrum of antitumor activity in in vitro cytotoxicity assays and tumor xenograft models. We did a phase I trial designed to determine the maximum tolerated dose and the pharmacokinetics of BMS-188797 when administered i.v. MATERIALS AND METHODS: BMS-188797 was administered i.v. over 60 minutes once every 21 days to 51 patients. The initial dose cohort of 3.75 mg/m(2) was set at approximately one third the lethal dose in dogs. Doses were subsequently escalated in cohorts according to a modified Fibonacci design. RESULTS: Fifty-one patients received a total of 160 cycles of therapy. The dose-limiting toxicity of febrile neutropenia occurred in two patients at the 200 mg/m(2) cohort. Moderate to severe sensory neuropathy occurred in 12 patients (24%). Four radiographic partial responses based on the Response Evaluation Criteria in Solid Tumors occurred: two in subjects with breast cancer, one in a subject with non-small cell lung cancer, and one in a subject with renal cell carcinoma. The duration of the partial responses observed were 24.1 months (renal cell carcinoma), 5.7 and 4.3 months (breast cancer), and 4.5 months (non-small cell lung cancer). Pharmacokinetics appear linear at doses through 110 mg/m(2) but not at higher doses. CONCLUSION: The dose-limiting toxicity in this single-agent study of BMS-188797 was febrile neutropenia. The recommended phase II dose of BMS-188797 as a single agent is 175 mg/m(2) i.v. for 1 hour administered every 3 weeks.

Phase I clinical and pharmacokinetic study of BMS-247550, a novel derivative of epothilone B, in solid tumors.

PURPOSE: The purpose of this study was to determine the maximum tolerated dose, toxicity, and pharmacokinetics of BMS-247550 administered as a 1-h i.v. infusion every 3 weeks. EXPERIMENTAL DESIGN: Patients with advanced solid malignancies were premedicated and treated with escalating doses of BMS-247550. Blood sampling was performed to characterize the pharmacodynamics and pharmacokinetics of BMS-247550. RESULTS: Twenty-five patients were treated at six dose levels ranging from 7.4 to 59.2 mg/m(2). At 50 mg/m(2), 4 of 9 patients (44.4%) had dose-limiting toxicity (neutropenia, abdominal pain/nausea). At 40 mg/m(2) (the recommended Phase II dose), 2 of 12 patients (16.7%) had dose-limiting neutropenia. Overall, the most common nonhematological toxicity was fatigue/generalized weakness (grade 3-4 seen in 9.0% of patients), followed by neurosensory deficits manifested as peripheral neuropathy and by gastrointestinal discomfort. At 40 mg/m(2), the incidence of grade 3 fatigue, abdominal pain, diarrhea, and neuropathy was 7.7%. Grade 1-2 neuropathy was observed in all patients enrolled and treated at 40 mg/m(2). Two patients with paclitaxel-refractory ovarian cancer, one patient with taxane-naïve breast cancer, and another patient with docetaxel-refractory breast cancer had objective partial responses (lasting 6.0, 5.3, 3.0, and 4.5 months, respectively). The mean pharmacokinetic parameter values during course 1 for clearance, volume of distribution, and apparent terminal elimination half-life at the 40 mg/m(2) (recommended Phase II dose) dose level were 21 liters/h/m(2), 826 liters/m(2), and 35 h (excluding one outlier of 516 h), respectively. Values during course 1 and course 2 were similar. CONCLUSIONS: The recommended dose for Phase II evaluation of BMS-247550 is 40 mg/m(2), although more long-term observations are needed. BMS-247550 has advantages over taxanes in relation to drug resistance and warrants further study.

Phase 1 and pharmacokinetic study of concurrent carboplatin and irinotecan in subjects aged 1 to 21 years with refractory solid tumors.

BACKGROUND: Preclinical testing suggests the combination of carboplatin and irinotecan has at least additive antitumor activity. The primary objectives of the current study were to determine the maximum tolerated doses (MTDs) and recommended phase 2 doses of carboplatin administered with irinotecan to pediatric patients with refractory solid tumors. METHODS: This was a multicenter, open-label, single-arm dose escalation study in which subjects with refractory solid tumors received 21-day treatment cycles of intravenous carboplatin on Day 1 followed by intravenous irinotecan administered daily for 10 days within 2 consecutive weeks. The plasma pharmacokinetics of ultrafiltrable platinum, irinotecan, and 2 irinotecan metabolites were determined during Cycle 1. The interpatient plan for dose escalation at study initiation was to increase irinotecan first followed by increases in carboplatin. RESULTS: Twenty-eight patients with a median age of 8.5 years (range, 1-21 years) were enrolled with a variety of solid tumors. Two of 6 subjects at the first dose level (carboplatin target area under the curve [AUC], 4.0 mg/mL*min; irinotecan, 18 mg/m2/dose) experienced dose-limiting gastrointestinal toxicities requiring a dose de-escalation scheme (carboplatin AUC, 4.0 mg/mL*min; irinotecan, 15 mg/m2/dose). Three of 6 subjects at the second dose level experienced dose-limiting gastrointestinal complications and bone marrow suppression. A further dose de-escalation to carboplatin AUC of 4.0 mg/mL*min and irinotecan of 12 mg/m2/dose resulted in dose-limiting bone marrow suppression in 1 of 13 patients treated at that dose, and therefore was determined to be the MTD. One complete response (in a patient with medulloblastoma) and 3 partial responses (in patients with neuroblastoma, medulloblastoma, and lymphoendothelial carcinoma, respectively) were observed. CONCLUSIONS: The recommended phase 2 dose in heavily pretreated pediatric patients is carboplatin (AUC, 4 mg/mL*min on Day 1) and irinotecan (12 mg/m2/dayx10 days) given every 21 days.

Biotransformation profiling of [(14)C]ixabepilone in human plasma, urine and feces samples using accelerator mass spectrometry (AMS).

Ixabepilone (BMS-247550, Ixempra is a semi-synthetic analog of the natural product epothilone B and marketed for its use in the treatment of cancer. A conventional human ADME study using decay counting methods for (14)C detection could not be conducted due to the radiolytic instability of [(14)C]ixabepilone at a typical specific activity (generally 1-10 microCi/mg). However, [(14)C]ixabepilone was sufficiently stable at low specific activity (1-2 nCi/mg). These low levels required the use of accelerator mass spectrometry (AMS) for radioactivity detection. The metabolic fate of this compound was investigated in eight patients following single intravenous doses of [(14)C]ixabepilone (70 mg, 80 nCi; specific activity: 1.14 nCi/mg). Metabolite profiles in pooled urine, feces and plasma samples were determined by HPLC-AMS analysis. The major radioactive component in urine and plasma was [(14)C]ixabepilone. Feces had a small amount of ixabepilone. There were numerous other drug-related components in both urine and fecal extracts (each <6% of the administered dose). LC/MS analysis of plasma, urine and feces samples showed the presence of three degradants of ixabepilone and several oxidative metabolites (M+16, M+14 and M-2 metabolites). This study demonstrates the utility of AMS in investigating the metabolite and excretion profiles of [(14)C]ixabepilone following administration to humans.

Phase I study of the novel epothilone analog ixabepilone (BMS-247550) in patients with advanced solid tumors and lymphomas.

PURPOSE: To establish the maximum-tolerated dose (MTD), dose-limiting toxicity (DLT), safety, pharmacokinetics, and pharmacodynamics of ixabepilone when administered as a 1-hour infusion every 3 weeks to patients with advanced solid tumors or relapsed/refractory non-Hodgkin's lymphoma. Dosing schedules of 40 mg/m2 and 50 mg/m2 over 3 hours were also evaluated. PATIENTS AND METHODS: Sixty-one patients were enrolled using an initial accelerated dose-escalation phase followed by a standard dose-escalation phase, with doses of ixabepilone ranging from 7.4 to 65 mg/m2. The pharmacokinetics of ixabepilone and two of its chemical degradation products were evaluated. Plasma pharmacodynamics were evaluated for both 1- and 3-hour infusions using an assay that measures the amount of endogenous tubulin in peripheral-blood mononuclear cells that exists in the polymerized versus the unpolymerized state. Response evaluation was performed every 6 weeks. RESULTS: The most common DLTs were neutropenia, stomatitis/pharyngitis, myalgia, and arthralgia. The MTD of ixabepilone as a 1-hour infusion every 3 weeks was established as 50 mg/m2. The maximum plasma concentration and area under the plasma concentration time curve appeared to increase less than proportionally to dose. Durable objective responses were seen in eight patients, including two complete responses. Five of the responders had experienced treatment failure with a taxane. CONCLUSION: The recommended dose of ixabepilone for the initiation of phase II studies on the basis of these results is 50 mg/m2 over 1 hour every 3 weeks. The promising efficacy and tolerability results demonstrated by ixabepilone in this study warrant its continued development.