Combination chemotherapy of carboplatin and gemcitabine against solid tumors: a phase I trial

Background. Some trials have suggested that the combination of gemcitabine and platinum compounds can have a synergistic effect on several solid tumors, but, at present, the data concerning carboplatin-gemcitabine combinations are not sufficient to allow the planning of phase II trials. The present phase I trial was planned to define the maximum tolerated dose and the dose-limiting toxicity of a carboplatin-gemcitabine combination. Methods. Thirty-two patients with advanced, pretreated solid tumors were treated with carboplatin on day 1 and gemcitabine on days 1, 8, and 15 every 28 days. The starting doses of carboplatin and gemcitabine were 3.5 mg/ml per min (area under the curve; AUC), and 600 mg/m², respectively. The doses of the two agents were alternately increased to 4, 4.5, and 5 mg/ml per min and to 800 and 960 mg/m², respectively. At each dose level, three patients were initially enrolled. If one of them experienced grade IV hematological toxicity or grade III–IV nonhematological toxicity (with the exception of alopecia), an additional three patients were enrolled at the same dose level. If two or more patients experienced grade IV hematological toxicity or grade III–IV non-hematological toxicity (with the exception of alopecia), the maximum tolerated dose was considered to have been reached, and the dose below this was recommended for further studies. All patients were evaluated weekly for toxicity and after every two courses of chemotherapy for response. Results. Dose-limiting toxicity was hematological, and the maximum tolerated doses were 4.5 mg/ml per min for carboplatin and 800 mg/m² for gemcitabine. The activity of the carboplatin/gemcitabine combination was encouraging, with a 21.9% response rate (7/32), three complete disease regressions, and a median time to progression of 30 weeks. The gemcitabine doses of day 15 or days 8 and 15 were omitted for hematological toxicity in 57 (50%) and 17 (14.9%) courses of chemotherapy, while no courses of chemotherapy were delayed for grade III–IV hematological or nonhematological toxicity. Conclusion. The maximum tolerated doses suggested by this trial are lower than those in other similar phase I trials, but they are consistent with those reported by most of the trials investigating gemcitabine either in combination with cisplatin or in heavily pretreated patients. Carboplatin 4.5 mg/ml per min on day 1 plus gemcitabine 800 mg/m² on days 1, 8, and 15 every 28 days may represent a promising schedule for further phase II trials. Received: January 29, 2001 / Accepted: September 13, 2001     

Tolerance,safety, and kinetics of the new antineoplastic compound dexniguldipine-HCl after oral administration: a phase I dose-escalation trial

Dexniguldipine-HCl is a new dihydropyridine compound that exerts selective antiproliferative activity in a variety of tumor models and, in addition, has a high potency in overcoming multidrug resistance. The purpose of this trial was to determine the toxicity and pharmacokinetics of dexniguldipine and to establish a recommended dose for phase II trials. A total of 37 patients with cancer were treated with oral dexniguldipine in increasing doses for up to 7 days. The main parameters evaluated were subjective tolerance and laboratory and cardiovascular parameters (blood pressure and ECG). Blood samples were drawn for analysis of the drug's pharmacokinetics. Dizziness and nausea were the major adverse events observed in seven patients, but episodes were generally mild and not clearly dose-related. Vomiting occurred in one patient. Hypotensive effects and orthostatic dysregulation were observed in some patients but were not considered to be dose-limiting. Therefore, no dose-limiting toxicity was found and the maximally tolerable dose could not be determined. Pharmacokinetic data showed wide interindividual variation and a dose-dependent increase in steady-state serum concentrations at doses of up to 1,000 mg daily, with no clear further increase being observed at higher doses. Consistently high concentrations were achieved with the 2,500-mg dose. Despite the lack of dose-limiting toxicity, higher doses of dexniguldipine do not appear to be useful for clinical evaluation because of the pharmacokinetics properties of the compound; therefore, 2,500 mg/day is recommended as the daily dose for phase II trials.This work was sponsored by Byk Gulden Pharmaceuticals, Konstanz, Germany     

Phase I clinical and pharmacokinetic trial of docetaxel and irinotecan administered on a weekly schedule

Background Docetaxel and irinotecan are synergistic agents with a broad spectrum of activity but overlapping myelosuppression. The study was designed to maintain dose intensity while limiting myelosuppression. The objectives of this study were to determine the maximal tolerated dose (MTD) of the combination of docetaxel and irinotecan administered weekly for four consecutive weeks every 42 days, to describe toxicities of this regimen, and to perform a pharmacokinetic analysis to evaluate changes in drug disposition as a function of dose as well as repeated dosing.Methods Adult patients with advanced solid tumors were treated with docetaxel followed by irinotecan. Doses of 30/50, 35/50, 35/66, 30/57, 30/65, 30/80 mg/m², respectively, were studied. Pharmacokinetics of docetaxel, irinotecan and SN-38 in plasma were determined on days 1 and 22 by a high-performance liquid chromatography (HPLC) assay.Results A total of 35 patients were treated. The MTD was docetaxel 30 mg/m² plus irinotecan 65 mg/m². Diarrhea was the dose-limiting toxicity; myelosuppression and other non-hematological toxicities were uncommon and mild. There were no significant differences in pharmacokinetic parameters between day 1 and day 22 (n=20). Five objective responses (breast, stomach and unknown primary) were observed among 30 evaluable patients. In addition, eight patients achieved stable disease.Conclusions The combination of weekly docetaxel and irinotecan is a well tolerated regimen and should be explored in phase II trials. This schedule maintains dose intensity and has limited myelosuppression.     

A phase I,dose escalation trial of ZD0473, a novel platinum analogue,in combination with gemcitabine

Purpose To develop a combination regimen for clinical testing, we performed a dose escalation study of ZD0473 in combination with gemcitabine. ZD0473 is a novel platinum analogue with an aliphatic cyclic carrier ligand. In vitro and in vivo studies suggest that it possesses a different spectrum of antitumor activity from cisplatin and carboplatin. In single-agent studies of ZD0473, myelosuppression was the predominant toxicity and responses were observed.Methods In this combination phase I trial, 36 patients with advanced cancer were accrued to four dose levels, with doses of ZD0473 and gemcitabine ranging from 60 to 120 mg/m² and 600 to 750 mg/m², respectively. ZD0473 was administered on day 1 and gemcitabine was given on days 1 and 8 of a 21-day cycle.Results Hematologic toxicity was dose-limiting. Grade 3 and 4 thrombocytopenia and neutropenia occurred during 60% and 41% of all cycles. Nonhematologic toxicities were mild and reversible. Two partial responses and 19 patients with stable disease were observed.Conclusions The recommended phase II doses are 90 mg/m² of ZD0473 and 750 mg/m² of gemcitabine for lightly pretreated patients and 600 mg/m² for heavily pretreated patients. The combination of ZD0473 and gemcitabine is associated with dose-dependent thrombocytopenia and neutropenia as well as having promising clinical activity.     

Therapeutic response and potential pitfalls in phase I clinical trials of anticancer agents conducted in Japan

The published reports of phase I clinical trials of anticancer agents conducted in Japan from 1981 to 1991 were reviewed. A total of 56 clinical studies that evaluated 38 different agents were reviewed. An average of five agents were studied each year. A total of 2200 patients had been recruited into the 56 clinical trials conducted during this period. A total of 91 patients (4.1%) responded to the treatment, with 23 showing a complete response (1.1%) and 48, a partial response (2.2%). In all, 62% of the responses were observed when patients were treated with doses ranging from 76% to 125% of the recommended doses for phase II studies. The response rates obtained for hematological malignancies were higher than those reported for other malignancies. The past status of phase I clinical trials in Japan can be summarized as follows. (1) A median of seven institutes participated in a single trial. The number of institutes participating correlated with the number of patients enrolled. However, too many institutes participated in a single phase I clinical trial in some studies. (2) The median duration of study for the clinical trials was 14 months. The duration of study was too long in some studies, considering the small number of patients enrolled. In conclusion, the methodology of phase I clinical trials of anticancer agents conducted in Japan should be improved in an efficient and scientific manner, especially for the testing of imported agents.     

Determination of vinca alkaloids in human plasma by liquid chromatography/atmospheric pressure chemical ionization mass spectrometry

 A sensitive assay was developed for the quantitation of vinblastine, desacetylvinblastine and vincristine using liquid chromatography-atmospheric pressure chemical ionization mass spectrometry (LC-APCI-MS). Analyses were performed on an Ultrasphere C₁₈ microbore column using ammonium acetate as mobile phase. The calibration curves were linear across the range of 0.51–4.00 ng/ml (0.63–4.93 nM) for vinblastine, 0.74–3.93 ng/ml (0.96–5.11 nM) for desacetylvinblastine and 0.30–3.95 ng/ml (0.36–4.79 nM) for vincristine. Vinca alkaloid concentrations were measured with an accuracy and precision within 11%. This assay could be implemented to determine the plasma concentrations for pharmacokinetic studies of vinblastine, desacetylvinblastine and vincristine in conjunction with clinical trials. Received: 15 December 1995 / Accepted: 16 June 1996     

Outcomes of research biopsies in phase I clinical trials: the MD anderson cancer center experience

Background.

Research biopsies are crucial for exploring the impact of novel agents on putative targets. The current study assesses the safety and success rate associated with performing such biopsies.

Methods.

We reviewed the medical records of 155 consecutive patients who had one or more research biopsies as part of a phase I trial from September 2004 to October 2009.

Results.

Of 281 research biopsies performed, 118 were paired before and after treatment biopsies (total = 236 biopsies). The most common sites of biopsy were superficial lymph node (19.9%), followed by liver (16.4%), and then soft tissue (15.7%). Ultrasound-guided biopsies were the most frequent type (53.7%). Among 142 patients who consented for mandatory biopsy, 86.6% had the biopsy performed, compared with 4.4% of 911 patients offered a biopsy on an optional basis (p < .0001). Biopsy was obtained most frequently on industry-sponsored trials; lack of funding on nonindustry trials was the most common reason that biopsies were not obtained. Of 281 single biopsies, only 4 (1.4%) had complications: pneumothorax requiring chest tube placement (n = 2), infection requiring admission (n = 1), and arrhythmia with hypotension (n = 1). All but one biopsy was successful in obtaining tissue. No deaths were attributable to biopsy.

Conclusions.

Our experience demonstrates that research biopsies in early phase clinical trials are safe (1.4% risk of serious complications), and a higher percentage of patients underwent mandatory biopsies (86.6%) compared with that of the patients with optional biopsies (4.4%).     

Initial clinical trial and pharmacokinetics of ThymitaqTM (AG337) by 10-day continuous infusion in patients with advanced solid tumors

Purpose: To establish the maximum tolerated dose (MTD), dose-limiting and other major toxicities and the major pharmacokinetic parameters of a 10-day infusion of the nonclassical antifolate Thymitaq^TM. Methods: The drug was given by 10-day infusion via a portable pump. The starting dose was 286 mg/m² per day with escalation to 572 and 716 mg/m² per day. Thymitaq in plasma was assayed by a validated isocratic reverse-phase HPLC assay with detection at 273 nm. Results: The dose of 716 mg/m² per day × 10 was considered too high as none of three patients completed a 10-day infusion and two of three developed grade IV myelotoxicity. At 572 mg/m² per day three of four patients completed a 10-day infusion. Dose-limiting myelosuppression was seen in one of four but owing to a high incidence of thrombotic phenomena, no further patients were added. Conclusion: Continuous 10-day infusions of Thymitaq should be limited to low doses until further studies can be done. Received: 4 March 1997 / Accepted: 14 July 1997     

A phase I/II trial of non-pegylated liposomal doxorubicin, docetaxel and trastuzumab as first-line treatment in HER-2-positive locally advanced or metastatic breast cancer

Aim

To assess the activity and safety of non-pegylated liposomal doxorubicin (Myocet®) in combination with docetaxel and trastuzumab as first-line treatment of patients with HER-2/neu-positive metastatic breast cancer (MBC).

Patients and methods

The maximum tolerated dose of the combination was defined in the phase I part of the study. In the phase II part, 45 HER-2/neu-positive MBC patients were enrolled to receive 6-8 cycles of Myocet® 50 mg/m² (day 1), docetaxel 30 mg/m² (days 2 and 9) plus trastuzumab (day 2, 4 mg/kg followed by 2 mg/kg/week) every 21 d until unacceptable toxicity or progression occurred. Objective response (primary end-point) and treatment tolerability were assessed according to World Health Organisation criteria. Cardiotoxicity was defined as signs and/or symptoms of congestive heart failure and/or a decrease in left ventricular ejection fraction (LVEF).

Results

The overall response rate was 55.6% (complete response 8.9%, partial response 46.7%), with a median time-to-progression of 10.9 months (C.I. 8.7-15.0). Median overall survival was not reached. The most frequent grade 3-4 adverse events were granulocytopaenia (60.0%), leukocytopenia (43.2%) and alopecia (35.6%). Grade 3-4 diarrhoea, pain, oral and skin toxicity (4.4%, each) and nausea/vomiting, thrombocytopenia and elevated alkaline phosphatase (2.2%, each) were also reported. In 2 patients LVEF fell to <50%, with a decrease from baseline >15%. LVEF median values remained stable from baseline to the end of the study (60%).

Conclusions

The combination of Myocet®, docetaxel and trastuzumab is safe and shows promising activity as first-line treatment of HER-2-positive MBC.     

Phase I/pharmacokinetic trial of the novel thioxanthone SR233377 (WIN33377) on a 5-day schedule

Purpose: SR233377 (WIN33377) is a novel 4-aminomethyl thioxanthone derivative with promising preclinical activity against solid tumors at doses substantially below the MTD. We performed a phase I trial to determine a suitable phase II dose of SR233377 when administered as a 2-h intravenous infusion for five consecutive days. Methods: A group of 25 patients with a range of solid tumor diagnoses and good performance status received SR233377 at eight dose levels ranging from 4.8 mg/m² per day to 74.7 mg/m² per day. Cycles were repeated every 35 days and patients were evaluated for response following two cycles of treatment. Doses were escalated in cohorts of three using a modified Fibonacci scheme. Pharmacokinetic sampling was performed during the first cycle in all patients. Results: Toxicities of SR233377 on this schedule included neutropenia, fever, nausea, and dyspnea but all were mild and not dose-limiting. Asymptomatic prolongation of the corrected QT (QTc) interval during infusion in all patients monitored at the 74.7 mg/m² dose level prompted closure of the study. QT lengthening correlated with increasing plasma concentrations of SR233377. SR233377 C_max values increased linearly with dose, but substantial interpatient variability in SR233377 AUC, clearance, and half-life was noted. There was no evidence of drug accumulation when day 1 and day 5 AUC and C_max values were compared. Seven patients displayed tumor growth inhibition lasting for 4 months or more. Conclusions: We conclude that SR233377 administered on a 5-day schedule is associated with tolerable clinical symptoms and some activity against a range of solid tumors but dosing is limited by QTc prolongation, a condition that predisposes to ventricular arrhythmias. Phase II development on this schedule is not recommended based on the occurrence of this concentration-dependent effect. Further investigation of alternative schedules of administration and of SR233377 analogues is warranted. Received: 24 August 1998 / Accepted: 17 December 1998     

Pharmacokinetics of 5,6-dimethylxanthenone-4-acetic acid (AS1404), a novel vascular disrupting agent, in phase I clinical trial

Purpose 5,6-Dimethylxanthenone-4-acetic acid (DMXAA) (AS1404) is a novel antitumour agent that selectively disrupts tumour vasculature and induces cytokines. The purpose of this study was to determine the pharmacokinetics (PK) of DMXAA in cancer patients enrolled in a phase I clinical trial. Methods DMXAA was administered as a 20-min i.v. infusion every 3 weeks and doses were escalated in cohorts of patients according to a predefined schema. PK samples were taken over the first 24 h of at least the first cycle. Results DMXAA was administered to 63 patients at 19 dose levels from 6 to 4,900 mg m⁻², and 3,700 mg m⁻² was established as the maximum tolerated dose. The PK observed over the dose range showed a non-linear fall in clearance from 16.1 to 1.42 l h⁻¹ m⁻² and resultant increase in the area under the concentration–time curve (AUC) from 1.29 to 12,400 μM h. In contrast, the increase in peak plasma concentrations from 2.17 to 1,910 μM approximated linearity. DMXAA was highly protein-bound to albumin (>99%) until saturation occurred at higher doses, leading to a rapid increase in the free fraction (up to 20%) and greater concentrations of DMXAA bound to non-albumin proteins. However, the main determinant of the non-linearity of the PK appeared to be sequential saturation of elimination mechanisms, which include hydroxylation, glucuronidation and perhaps hepatic transport proteins. This resulted in an exaggerated non-linear increase in free DMXAA plasma concentrations and AUC compared to total drug. Conclusions The PK of DMXAA are well-defined, with a consistent degree of non-linearity across a very large dose range.     

A phase I-II trial of heavy charged particle irradiation of malignant glioma of the brain: a Northern California Oncology Group Study

Thirty-nine patients with primary or recurrent glioma of the brain were irradiated wholely or in part with heavy charged particle beams at the University of California Lawrence Berkeley Laboratory in a Phase I-II clinical trial of the Northern California Oncology Group. During the course of this trial, treatment techniques have been developed and tumor doses have been escalated in order to obtain data on normal brain toxicity and response of malignant glioma of the brain. Toxicity has been acceptable with a low level of brain injury. Survival and tumor control has been approximately the same as historical results in glioma of the brain. Further dose escalation is planned together with possible trial of combined modality therapy.     

Novel paclitaxel formulations for oral application: a phase I pharmacokinetic study in patients with solid tumours

Purpose To explore the pharmacokinetics (PKs) of paclitaxel and two major metabolites after three single oral administrations of a novel drinking solution and two capsule formulations in combination with cyclosporin A (CsA) in patients with advanced cancer. Moreover, the tolerability and safety of the formulations was studied. In addition, single nucleotide polymorphisms in the multidrug resistance (MDR1) gene were determined. Patients and methods Ten patients were enrolled and randomized to receive CsA 10 mg/kg followed by oral paclitaxel 180 mg given as (1) drinking solution (formulation 1), (2) capsule formulation 2B, and (3) capsule formulation 2C on day 1, 8, or 15. Results The median C _max of paclitaxel was 0.42 (0.23–0.96), 0.48 (0.08–0.59), and 0.39 (0.11–1.03) μg/ml and the area under the plasma concentration–time curve was 2.83 (1.69–5.12), 2.01 (1.57–3.04), and 2.67 (1.05–3.61) μg h/ml following administration of formulations 1, 2B, and 2C, respectively. The novel formulations were tolerated after single oral dose without causing relevant gastrointestinal or haematological toxicity. Conclusions The PK and metabolism of paclitaxel were comparable between the oral formulations co-administered with CsA.     

A phase I trial of 3-aminopyridine-2-carboxaldehyde thiosemicarbazone in combination with gemcitabine for patients with advanced cancer

Purpose 3-Aminopyridine-2-carboxaldehyde thiosemicarbazone (3-AP), a new and potent inhibitor of ribonucleotide reductase (RR), increases the cellular uptake, DNA incorporation, and cytotoxicity of gemcitabine in tumor cell lines. A phase I trial was initiated to determine the safety profile and maximum tolerated doses of 3-AP and gemcitabine when used in combination in patients with advanced cancer.Study design 3-AP and gemcitabine were administered on days 1, 8, and 15 of each 28-day cycle. Initially, 3-AP was infused over 2 h at a fixed dose of 105 mg/m². Gemcitabine was given over 30 min beginning no less than 1 and no more than 4 h after 3-AP. The first cohort received 3-AP alone in the first cycle. Subsequently, the gemcitabine dose was escalated beginning at 600 mg/m² in cohorts of three to six patients. Following the gemcitabine 1000 mg/m² dose level, the study was amended to determine if the 3-AP dose could be escalated above 105 mg/m².Results 3-AP at 105 mg/m² administered over 2 h followed in 1–4 h by gemcitabine at 1000 mg/m² produced a toxicity profile similar to that expected for gemcitabine alone at the same dose. When the dose of 3-AP was escalated to 140 and 185 mg/m² administered over 2 h and subsequently over 4 h, acute hypotension, hypoxia, and EKG changes including non-specific ST-T wave changes and mild QT prolongation were observed, and one patient with underlying diffuse coronary artery disease had an asymptomatic myocardial infarction. 3-AP was shown to cause mild, reversible methemoglobinemia. Average end-of infusion serum concentrations for 3-AP at all doses were within the range capable of enhancing gemcitabine cytotoxicity in vitro. Gemcitabine plasma concentrations at end-of-infusion and elimination half-life were consistent with values reported in the literature. Among 22 evaluable patients, one complete response and two partial responses were observed, and an additional patient had prolonged stabilization of a large liver metastasis.Conclusions 3-AP at 105 mg/m² infused over 2–4 h followed by gemcitabine at 1000 mg/m² on a days 1, 8, and 15 schedule every 28 days was generally well-tolerated and had a toxicity profile similar to that of gemcitabine alone. 3-AP produced mild to modest methemoglobinemia, which could cause acute symptoms in patients with limited pulmonary or cardiovascular reserve. The combination demonstrated antitumor activity and merits further exploration in phase II trials.     

Schedule-dependent activity of 5-fluorouracil and irinotecan combination in the treatment of human colorectal cancer: in vitro evidence and a phase I dose-escalating clinical trial

Several schedules of 5-fluorouracil (FU) and irinotecan (IRI) have been shown to improve overall survival in advanced colorectal cancer (CRC). Preclinical evidence suggests that the sequential administration of IRI and FU produces synergistic activity, although their clinical use has not been fully optimised. We investigated the interaction between short-term exposure to SN-38, the active metabolite of IRI, and prolonged exposure to FU in human CRC HT-29 cells and observed that the synergism of action between the two agents can be increased by extending the time of cell exposure to FU and reducing the interval between administration of the two agents. Based on these findings, we performed a phase I trial in 25 advanced CRC patients using a modified IRI/FU regimen as first-line therapy and evaluated three dose levels of IRI (150-300 mg/m(2)) and two of continuous infusion of FU (800-1000 mg/m(2)) in a 3-weekly schedule. The most severe grade III-IV toxicities were neutropoenia in four cycles and diarrhoea in three. One patient achieved complete response (4%), 12 a partial response (48%), the overall response rate was 52% (+/-20, 95% CI); seven of 25 patients had stable disease (28%), the overall disease control was 80% (+/-16, 95% CI). This modified IRI/FU schedule is feasible and exhibits potentially interesting clinical activity.     

A phase I/II trial of a WT1 (Wilms' tumor gene) peptide vaccine in patients with solid malignancy: safety assessment based on the phase I data

OBJECTIVE: We conducted a phase I study to investigate the safety of a weekly WT1 tumor vaccine therapy in patients with solid tumors that had been refractory to all other anti-cancer therapies. METHODS: Skin-test-negative patients were intradermally injected weekly for 12 weeks with 3.0 mg of an HLA-A*2402-restricted modified 9-mer WT1 peptide emulsified in Montanide ISA51 adjuvant. We estimated the Bayesian posterior probability of the occurrence of grade 3 or 4 toxicity when receiving the weekly WT1 vaccination. This analysis provided the basis for making a decision to terminate the phase I study and switch to phase II. Moreover, we performed an exploratory assessment of the anti-tumor effects of WT1 treatment. RESULTS: Ten patients received 114 vaccinations with WT1 on a weekly schedule. No grade 3 or 4 toxicities were observed. Based on the Bayesian approach, it was highly likely that the probability of grade 3 or 4 toxicity was below 20% (the posterior probability = 0.914). Fifteen grade 2 and two grade 1 toxicities were observed; all of these incidents, however, were determined by the Independent Data and Safety Monitoring Committee to be unrelated to the WT1 treatment. One patient exhibited a partial response; five additional patients had stable disease while receiving weekly WT1 treatment. CONCLUSION: This paper confirms that the potential toxicities of the treatment schedule of weekly WT1 vaccination are acceptable and suggested a potential anti-tumor effect. Consequently, we validated the decision to continue to the phase II trial.     

Tumour targeting of humanised cross-linked divalent-Fab' antibody fragments: a clinical phase I/II study

Antibody engineering has made it possible to design antibodies with optimal characteristics for delivery of radionuclides for tumour imaging and therapy. A humanised divalent-Fab' cross-linked with a bis-maleimide linker referred to as humanised divalent-Fab' maleimide was produced as a result of this design process. It is a humanised divalent antibody with no Fc, which can be produced in bacteria and has enhanced stability compared with F(ab')(2). Here we describe a clinical study in patients with colorectal cancer using humanised divalent-Fab' maleimide generated from the anti-carcinoembryonic antigen antibody A5B7 radiolabelled with iodine-131. Ten patients received an i.v. injection of iodine-131-labelled A5B7 humanised divalent-Fab' maleimide, and positive tumour images were obtained by gamma camera imaging in eight patients with known lesions, and one previously undetected lesion was identified. True negative results were obtained in two patients without tumour. Area under the curve analysis of serial blood gamma counting and gamma camera images showed a higher tumour to blood ratio compared to A5B7 mF(ab')(2) used previously in the clinic, implying this new molecule may be superior for radioimmunotherapy. MIRD dose calculations showed a relatively high radiation dose to the kidney, which may limit the amount of activity that could be administered in radioimmunotherapy. However the reduction in immunogenicity was also a major advantage for A5B7 humanised divalent-Fab' maleimide over murine versions of this antibody suggesting that humanised divalent-Fab' maleimide should be a useful vehicle for repeated therapies.     

A phase I trial of gemcitabine administered as a 96-h continuous intravenous infusion in patients with advanced carcinoma and lymphoma

Background and objective Preclinical data suggest gemcitabine may have schedule-dependent activity fovoring prolonged infusion. We sought to determine the recommended phase II dose (RPTD) and toxicity of gemcitabine when given as a continuous intravenous (CIVI) over 96 h. Patients and methods Gemcitabine was initially given at 1 mg/m²/d for 48, then, 72, and finally 96 h. The dose was then increased to 2, 4, 6, 10, 15, 20, and 25 mg/m²/d. Dose levels of 7, 8, 9 mg/m²/d as 96-h infusion were added later after a protocol modification. After identifying the RPTD using an every 3-wk schedule. we then evaluated the feasibility of repeating the infusion every 2 wk, and then weekly for 3 of 4 wk. Results Thirty-four patients with a variety of tumor types received a total of 126 cycles of therapy (median of 2 cycles, range 1–10 cycles). The RPTD, was 8 mg/m²/d every 3 wk, and 6 mg/m²/d every 2 wk. The most common grade 2 or higher toxicities at all dose levels (>- grade 2) included fever (n=14), dyspnea (n=7). mucositis (n=6), hypotension (n=6), nausea/vomiting (n=6), and fatigue (n=5). Neutropeni and/or thrombocytopenia were uncommon. Conclusion A dministration of gemcitabine as a 96-h infusion results in a markedly different toxicity profile and RPTD than when given by a conventional 30-min infusion. The RPTD was 8 mg/m²/d (32 mg/m²/course) when given every 3 wk, or 6 mg/m²/d (24 mg/m²/course) when given every 2 wk.