Phase I clinical and pharmacokinetic study of mitoxantrone given to patients by intraperitoneal administration

On the basis of its high degree of cytotoxicity against fresh human ovarian cancers and its relative lack of vesicant activity, mitoxantrone administered by the i.p. route was studied in a Phase I and pharmacokinetic trial. Thirty-three patients with good performance status and diagnoses of metastatic or recurrent ovarian (31 patients) and colon (two patients) cancers were treated with 12- to 38-mg/m2 doses, administered by the i.p. route every 4 wk for up to ten treatment courses. Mitoxantrone doses were escalated at 2- to 3-mg/m2 increments in groups of three to 11 patients. Thirty-eight mg/m2 (by i.p. dwell without removal) were considered the maximally tolerated dose in that, of eight treated patients, four experienced severe leukopenia and six experienced severe abdominal pain. Response to i.p. mitoxantrone was evaluable in 17 patients. None of seven patients with clinically measurable intraabdominal or pelvic tumor masses responded; however, in three (50%) of six patients with nonmeasurable disease, there was normalization of previously elevated serum CA-125 concentrations for 3, 17, and 24 mo. Additionally, two (50%) of four patients who underwent third-look laparotomies were found to have greater than 75% reductions in i.p. tumor masses with response lasting 24 and 25 mo. At 38 mg/m2, mitoxantrone was associated with a mean concentration.time product of 100 micrograms.h/ml in the i.p. space and of 0.071 micrograms.h/ml in plasma, yielding an i.p./plasma area under the curve ratio of 1408. We conclude that chemical peritonitis is the dose-limiting toxicity of i.p. administered mitoxantrone and that a dose of 23 mg/m2 every 3 to 4 wk should be used in future Phase II trials in ovarian cancer patients with minimal residual intraabdominal and pelvic disease following second-look laparotomy.     

Phase I/pharmacokinetic study of intraperitoneal cisplatin and etoposide

We administered cisplatin and etoposide by peritoneal dialysis to 39 patients with i.p. malignancies in order to investigate the toxicity, pharmacokinetics, and clinical activity of this 2-drug combination. All patients received i.v. sodium thiosulfate concurrently with the i.p. chemotherapy. Myelosuppression, nausea, vomiting, and malaise were the primary toxicities encountered. The maximum tolerated dose of etoposide was 350 mg/m2, when administered with a fixed dose of cisplatin, 200 mg/m2. Although the total (free and protein-bound) etoposide exposure for the peritoneal cavity was only 1.5-fold greater than that for the plasma, the free (non-protein bound) etoposide peritoneal exposure was 65-fold greater than the plasma. Tumor regressions were noted in patients with ovarian and pancreatic carcinomas. This study is the first demonstration of the large pharmacokinetic advantage that exists for the i.p. administration of highly protein-bound drugs, and it also documents the clinical activity of i.p. cisplatin and etoposide.     

A phase I and pharmacokinetic study of intraperitoneal topotecan.

PURPOSE: To evaluate the feasibility and pharmacology of intraperitoneal (IP) topotecan. PATIENTS AND METHODS: Fifteen patients with recurrent ovarian cancer in a phase I trial were treated with escalating IP topotecan doses (5-30 mg/m(2)) for pharmacokinetic analysis. RESULTS: Dose limiting toxicity (DLT) was acute hypotension, chills and fever at the 30 mg/m(2) dose level. Haematological toxicity and abdominal pain were mild for all dose levels studied. PHARMACOKINETICS: Peak plasma levels of total topotecan were reached at 2.7 +/- 1.1 h after IP instillation. The apparent V(ss) was 69.9 +/- 25.4 L/m(2), plasma clearance 13.4 +/- 2.5 L/h/m(2) and plasma T1/2 3.7 +/- 1.3 h. The plasma AUC was correlated with the dose (R = 0.95, P < 0.01). The plasma AUC ratio of lactone versus total topotecan (lactone + carboxy-forms) increased with the dose from 16% to 55%, (R = 0.84, P < 0.01). Peritoneal total topotecan was cleared from the peritoneal cavity at 0.4 +/- 0.3 L/h.m(2) with a T1/2 = 2.7 +/- 1.7 h. The mean peritoneal/plasma AUC ratio for total topotecan was 54 +/- 34. CONCLUSION: A substantial dose of topotecan can be delivered by the IP route, achieving cytotoxic plasma levels of topotecan, with acceptable toxicity. The recommended dose for further phase II trials is 20 mg/m(2) IP, which enables combination with active doses of other cytotoxic drugs, in view of its limited myelotoxicity when given by this route.     

Intrathecal 6-mercaptopurine: preclinical pharmacology, phase I/II trial, and pharmacokinetic study

For over 30 years, oral 6-mercaptopurine (6-MP) has been a mainstay of systemic maintenance therapy for acute lymphoblastic leukemia. Despite its efficacy as an antileukemic agent, 6-MP has not been previously administered by the intrathecal (IT) route. In anticipation of a clinical trial of IT 6-MP, preclinical cytotoxicity and pharmacology studies were performed to define a safe, effective dose. The optimal concentration (greater than 1 microM) and duration of exposure (greater than 12 h) to 6-MP required for cytotoxicity were determined in vitro using human leukemia cell lines. The dose required to achieve the desired cerebrospinal fluid concentrations in humans was derived from pharmacokinetic parameters determined in rhesus monkeys. A phase I/II study was then performed in pediatric patients with refractory meningeal leukemia. Nine patients (aged 3.5 to 16 years) with chronic meningeal leukemia (2 to 6 central nervous system relapses) were entered onto the study. All had previously failed, at a minimum, IT methotrexate, IT cytarabine, and cranial (+/- spinal) radiation. A 10-mg IT dose of 6-MP (calculated to produce cytotoxic cerebrospinal fluid levels for 12 h) was administered twice weekly for 4 weeks. There were four complete responses and three partial responses. The duration of complete responses ranged from 7 to 22 weeks. Observed toxicities were not dose limiting and included mild headache (three patients) and minimal nausea (two patients). Pharmacokinetic studies performed in patients confirmed that cerebrospinal fluid concentrations of 6-MP were greater than 1 microM for 12 h. These results indicate that the IT administration of 6-MP is feasible, is not associated with significant toxicity, and has definite activity in patients with refractory meningeal leukemia.     

Platinum analogue combination chemotherapy: cisplatin and carboplatin--a phase I trial with pharmacokinetic assessment of the effect of cisplatin administration on carboplatin excretion

Cisplatin (NSC 119875) and carboplatin (NSC 241240) are platinum (II) analogues with very different spectra of toxicity. Cisplatin dose is limited by nausea and vomiting, renal dysfunction, and dose-related peripheral neuropathy, whereas carboplatin is myelosuppressive. There are also clinical and laboratory data that suggest that these drugs may not be completely cross-resistant. Therefore, the following phase I trial of combination therapy with cisplatin and carboplatin was undertaken. Since carboplatin toxicity is enhanced in the presence of renal impairment, carboplatin excretion was also evaluated in selected patients at the maximum tolerated dose. Thirty-three patients received 50 mg/m2 cisplatin and doses of carboplatin between 160 mg/m2 and 400 mg/m2. Sequential 20-minute infusions of carboplatin and then cisplatin were able to be administered at the standard doses of carboplatin (320 and 400 mg/m2) with thrombocytopenia to the degree expected if carboplatin alone had been given. However, 280 mg/m2 carboplatin followed by 25 mg/m2 cisplatin/d X 3 caused unexpectedly severe thrombocytopenia in seven of eight patients (median platelet nadir 45,000/microL; range, 12 to 321,000/microL; nadir was less than 90,000 in seven of eight patients). In three patients treated with 280 mg/m2 carboplatin plus 25 mg/m2/d X 3 cisplatin, pharmacokinetics of carboplatin were compared during consecutive monthly cycles without and with cisplatin. Modestly increased areas under the curve (AUC) for carboplatin (15% and 35%) with cisplatin were seen in the two patients who experienced more pronounced platelet suppression with combination therapy. No other limiting or unusual toxicity was seen with this combination. Responses, primarily in "platinum responsive" tumors, were seen. The combination of cisplatin plus carboplatin is feasible and merits further study.     

A phase I and pharmacokinetic study of intraperitoneal carboplatin and etoposide.

BACKGROUND: We attempted to determine the maximum tolerated dose and toxicity of etoposide (VP-16) when administered in combination with carboplatin (CBDCA) (300 mg m-2) and administered via the intraperitoneal (IP) route. METHODS AND MATERIALS: A total of 26 patients were treated on this trial. CBDCA was administered at a fixed dose of 300 mg m-2) while VP-16 was started at a dose of 200 mg m-2 and escalated at 50 mg m-2 increments. Both agents were mixed together in 2 litres of 5% Dextrose and administered as quickly as possible into the peritoneal cavity. Pharmacokinetic studies were performed at the maximum tolerated dose (MTD). RESULTS: The MTD for this regimen was CBDCA 300 mg m-2 and VP-16 350 mg m-2. Patients > or = 70 years of age or who had received more than six cycles of previous chemotherapy, tolerated this regimen poorly. The MTD for this group of patients was CBDCA 200 mg m-2 and VP-16 50 mg m-2. Neutropenia was the dose limiting toxicity for both groups. The mean peritoneal/plasma peak ratio was 18.3 for CBDCA and 12.7 for VP-16. The pharmacologic advantage (peritoneal/plasma AUC ratio) was 14.9 for CBDCA and 8.8 for VP-16. Although measurable disease was not a requirement for entrance into this study a response rate of 27% was noted in 15 patients with evaluable disease who had ovarian cancer. CONCLUSIONS: A pharmacologic advantage exists for both CBDCA and VP-16 when administered together via the IP route.     

A phase I and pharmacokinetic study of gemcitabine given by 24-h hepatic arterial infusion

PurposeThis study was performed to assess the toxicities, the maximum-tolerated dose (MTD), the pharmacokinetics and the anti-tumour activity of gemcitabine given by 24-h hepatic arterial infusion (HAI).Patients and methodsPatients with liver malignancies received gemcitabine by 24-h HAI, weekly × 3, every 4 weeks. On day 1 or day 8 of the first cycle, patients received one administration by 24-h intravenous infusion for pharmacokinetic comparison and to determine hepatic extraction.ResultsThirteen patients received gemcitabine at the dose levels of 75, 135 and 180 mg/m². The MTD was 180 mg/m² with thrombocytopaenia as the dose-limiting toxicity. Pharmacokinetic analysis showed a significantly lower maximum gemcitabine plasma concentration (C_max: HAI, 26, 80 and 128 nM, respectively; IV, 229, 264 and 293 nM, respectively) and area under the plasma-concentration-versus-time curve (AUC_0–24h: HAI, 386, 1247 and 2033 nmol × h/L, respectively; IV, 3526, 4818 and 5363 nmol × h/L, respectively) during HAI, compared with intravenous infusion (both P < 0.001). Additionally, the mean hepatic extraction ratios of gemcitabine at the 75, 135 and 180 mg/m² dose level were 0.89, 0.75 and 0.55, respectively. Hepatic extraction decreased linearly with increasing dose. The C_max and AUC_0–24h of 2′,2′-difluoro-2′-deoxyuridine, the deaminated product of gemcitabine, were similar for HAI and intravenous infusion. Seven patients had stable disease for a median duration of 9 months (range: 2–11 months).ConclusionsGemcitabine given by 24-h HAI was well tolerated and resulted in significantly lower systemic gemcitabine plasma concentrations than intravenous infusion due to a relatively high hepatic extraction.     

Continuous administration of irinotecan by hepatic arterial infusion: a phase I and pharmacokinetic study.

PURPOSE: The main advantage of administering chemotherapy by means of hepatic arterial infusion (HAI) is the achievement of a high concentration of the drug in the liver. Irinotecan (CPT-11) is an active agent for the treatment of advanced colorectal cancer and other tumor types, which frequently metastasize in the liver. We performed a Phase I and pharmacokinetic study to investigate CPT-11 by hepatic arterial administration in patients with liver metastases. PATIENTS AND METHODS: Patients with liver metastases received CPT-11 at doses ranging from 15 to 25 mg/m(2)/day for 5 days every 3 weeks by continuous HAI. All of the patients also received one cycle CPT-11 i.v. Primary end points of the study were to define the maximum tolerated dose (MTD) of hepatic arterial CPT-11 and to study its pharmacokinetics. RESULTS: Twenty patients were included. The MTD was 25 mg/m(2)/day and the dose-limiting toxicities were neutropenia and diarrhea. The metabolic ratio was significantly increased with HAI compared with i.v. administration (P = 0.015). The steady-state concentrations of total CPT-11 and CPT-11 carboxylate and lactone were all lower than those during i.v. infusion (P = 0.008, 0.013, and 0.004, respectively), whereas the levels of total SN-38, and SN-38 carboxylate, lactone, and glucuronide were similar. The total body clearance of CPT-11 was significantly higher with HAI (P = 0.008). CONCLUSIONS: The MTD of CPT-11 given by hepatic 5-day continuous infusion was 25 mg/m(2)/day. HAI of CPT-11 resulted in a higher metabolic ratio because of increased elimination of CPT-11. We recommend 20 mg/m(2)/day for additional Phase II studies.     

Significance and effects of intraperitoneal cisplatin administration for ovarian cancer

We studied the efficacy and safety of combination chemotherapy in which a high-dose platinum agent was administered intraperitoneally (i.p.) plus intravenously (i.v.) to 22 patients with stage III ovarian cancer. The chemotherapy consisted of etoposide (i.p.), cisplatin (i.p.), and carboplatin (i.v.). Each course was repeated every 4 weeks and a maximum of 5 courses was given in the 6 months following the initial surgery. As a control, 13 patients received different chemotherapy (CAP etc.) in which cisplatin, cyclophosphamide and doxorubicin pirarubicin hydrochloride were administered. The mean (SD) total dose of cisplatin in the patient group group (790.6 +/- 317.0 mg/m2) over the 6 months was significantly higher than in the control group (377.2 +/- 215.1 mg/m2). The overall response rate (CR + PR) 6 months after the completion (95.5%) was significantly higher in the study patients than in the control group (53.1%). The 1, 3, 5-year survival rates were significantly higher in the EPJ group (91.0, 59.0, 42.1%) than in the control group (53.8, 15.4, 15.4%). There was no significant difference in renal toxicity or bone marrow suppression (leukopenia and thrombocytopenia) between the two groups. EPJ therapy allowed an increased dose of cisplatin in the treatment of ovarian cancer without enhancing renal toxicity, resulting in higher response and survival rates. This study demonstrated that this therapy is an effective and well-tolerated regimen.     

Intraperitoneal cisplatin with intraperitoneal gemcitabine in patients with epithelial ovarian cancer: results of a phase I/II Trial.

PURPOSE: The aims of this study were to determine the dose and schedule of i.p. cisplatin with i.p. gemcitabine in patients with persistent disease at second-look assessment, the toxicity of this regimen, and the time to treatment failure and overall survival. EXPERIMENTAL DESIGN: We performed a Phase I/II evaluation of i.p. cisplatin at 75 mg/m(2) on day 1 with planned gemcitabine at 500, 750, 1000, or 1250 mg/m(2) i.p. on days 1, 8, and 15 on a 28-day schedule for four courses. Eligible patients completed surgical cytoreduction followed by adjuvant platinum-based chemotherapy. They had second-look assessment showing microscopic or macroscopic (< or =1 cm) disease, followed by i.p. port placement. RESULTS: The Phase I dose-limiting toxicity was grade 3 thrombocytopenia at day 15 on dose level 1 (n = 5). The protocol was amended, and the Phase II portion accrued to 30 patients, who were given i.p. cisplatin (75 mg/m(2)) on day 1 and gemcitabine at 500 mg/m(2) on days 1 and 8 on a 21-day schedule for four courses. Nine patients were removed from the study: one each for hypersensitivity, cellulitis, and i.p. port malfunction; two for progression of disease; and four for renal toxicity. Other toxicities included grade 3 nausea (7%) and transient grade 3 neuropathy (3%). Grade 1 or 2 neuropathy was frequently seen (80%). Five patients (17%) returned to the operating room at a median of 6 months (range, 1-20 months) after i.p. therapy for evaluation of abdominal pain; two patients had recurrence, and all had areas of fibrous tissue with encasement of the bowel. In two patients, the fibrous tissue was causing partial bowel obstruction. No other patients had symptoms prompting surgical exploration. Pharmacokinetic (PK) studies showed a median area under the curve (AUC) i.p. of 3041 h. micro M (range, 676-5702 h. micro M) and AUC in plasma of 4.0 h. micro M (range, 0.92-8.2 h. micro M) reached between 120 and 240 min; the pharmacological advantage was 759-fold (range, 217-1415-fold) for i.p. versus plasma drug levels. The mean residence time of gemcitabine with i.p. administration was 4.7 h. The median time to progression of the intent to treat population was 15.93 months (95% confidence interval, 9.13-25.9 months), with a median overall survival of 43.5 months [95% confidence interval, (34.66- infinity)]. No statistical differences were seen with respect to overall survival if patients were grouped in terms of optimal debulking or not (median not reached versus 34.8 months, respectively; P = 0.16) or whether visible disease was present or not at the start of i.p. therapy (34.8 versus 47.7 months; P = 0.47). With regard to time to treatment failure, a statistical difference favored patients with optimal versus nonoptimal primary debulking (25.2 versus 10.2 months, respectively; P = 0.03). CONCLUSIONS: The median time to treatment failure and overall survival of 15.9 months and 43.5 months, respectively, are consistent with our historical data in patients receiving i.p. platinum-based regimens for consolidation. The fibrotic changes seen in explored patients suggest local toxicity of this combination. The absolute benefit of i.p. consolidation requires randomized trials to assess efficacy.     

Fractionated administration of irinotecan and cisplatin for treatment of lung cancer: a phase I study

A combination chemotherapy of irinotecan (CPT-11) and cisplatin (CDDP) has been reported to be active for lung cancer. In the previous trial, however, diarrhoea and leucopenia became the major obstacle for sufficient dose escalation of CPT-11 to improve the treatment outcome. We conducted a phase I study to investigate whether the fractionated administration of CDDP and CPT-11 at escalated dose was feasible and could improve the treatment outcome. Twenty-four previously untreated patients with unresectable non-small-cell lung cancer (NSCLC) or extensive disease of small-cell lung cancer (SCLC) were eligible. Both CDDP and CPT-11 were given on days 1 and 8, and repeated every 4 weeks. The dose of CDDP was fixed at 60 mg m(-2) and given by 1-h infusion before CPT-11 administration. The starting dose of CPT-11 was 40 mg m(-2), and the dose was escalated by an increase of 10 mg m(-2). The maximally tolerated dose of CPT-11 was determined as 60 mg m(-2) because grade 4 haematological or grade 3 or 4 non-haematological toxicities developed in six patients out of 11 patients evaluated. Diarrhoea became a dose-limiting toxicity. The objective response rates were 76% for NSCLC and 100% for SCLC. The recommended dose of CPT-11 and CDDP in a phase II study will be 50 mg m(-2) and 60 mg m(-2) respectively.     

L-histidinol: preclinical therapeutic studies in combination with antitumor agents and pharmacokinetic studies in mice.

Therapeutic studies were conducted with L-histidinol, in combination with cyclophosphamide, bischloroethylnitrosourea, 5-fluorouracil, phenylalanine mustard, or cis-platinum(II)diammine dichloride, in several transplantable tumors in mice. These tumor types included murine L1210 P388 leukemias, M5076 sarcoma, mammary 16/C adenocarcinoma, human LOX melanoma, and colon HT-29 adenocarcinoma. Therapeutic benefits of adding L-histidinol to a regimen, compared to the regimen alone, were marginal. Pharmacokinetic studies indicated a rapid clearance of L-histidinol following a bolus dose (250 mg/kg i.p.), peak plasma concentration of 200 micrograms/ml (1.4 mM), and beta phase t1/2 of 12.6 min. Maximum tolerable plasma steady state concentrations with a 24-h infusion (2000 mg/kg/24 h) were no greater than 25 micrograms/ml (0.18 mM).     

A phase I and pharmacokinetic study of paclitaxel poliglumex and cisplatin in patients with advanced solid tumors

Purpose  Determine the toxicity, maximum tolerated dose (MTD), and pharmacokinetics of paclitaxel poliglumex (PPX; CT-2103) in combination with cisplatin administered every 3 weeks. Patients and methods  Forty-three patients with advanced solid tumors were treated at escalating doses of PPX with a fixed dose of cisplatin at 75 mg/m². Conjugated and unconjugated paclitaxel were measured in plasma and urine. Cisplatin, as total platinum content in urine, was also assayed. Results  Dose-limiting toxicities included neutropenia and neuropathy with a cycle 1 MTD of 210 mg/m². Conjugated taxanes had a prolonged half-life of >100 h. Nine patients had partial responses, and 19 had stable disease. Conclusions  PPX is a water-soluble paclitaxel-polymer conjugate with a prolonged half-life and a limited volume of distribution. PPX/cisplatin showed good activity in a refractory patient population; however, cumulative neuropathy was a significant issue at high doses, suggesting that a lower dose may be appropriate for prolonged therapy. The authors who are not employed by Cell Therapeutics do not have disclosure to make.     

Experimental designs for phase I and phase I/II dose-finding studies

We review the rationale behind the statistical design of dose-finding studies as used in phase I and phase I/II clinical trials. We underline what the objectives of such dose-finding studies should be and why the widely used standard design fails to meet any of these objectives. The standard design is a "memoryless" design and we discuss how this impacts on practical behaviour. Designs introduced over the last two decades can be viewed as designs with memory and we discuss how these designs are superior to memoryless designs. By superior we mean that they require less patients overall, less patients to attain the maximum tolerated dose (MTD), and concentrate a higher percentage of patients at and near to the MTD. We reanalyse some recently published studies in order to provide support to our contention that markedly better results could have been achieved had a design with memory been used instead of a memoryless design.     

A phase I/II pharmacokinetic and pharmacogenomic study of calcitriol in combination with cisplatin and docetaxel in advanced non-small-cell lung cancer

Background

Preclinical studies demonstrated antiproliferative synergy of 1,25-D₃ (calcitriol) with cisplatin. The goals of this phase I/II study were to determine the recommended phase II dose (RP2D) of 1,25-D₃ with cisplatin and docetaxel and its efficacy in metastatic non-small-cell lung cancer.

Methods

Patients were ≥18 years, PS 0–1 with normal organ function. In the phase I portion, patients received escalating doses of 1,25-D₃ intravenously every 21 days prior to docetaxel 75 mg/m² and cisplatin 75 mg/m² using standard 3 + 3 design, targeting dose-limiting toxicity (DLT) rate <33 %. Dose levels of 1,25-D₃ were 30, 45, 60, and 80 mcg/m². A two-stage design was employed for phase II portion. We correlated CYP24A1 tagSNPs with clinical outcome and 1,25-D₃ pharmacokinetics (PK).

Results

34 patients were enrolled. At 80 mcg/m², 2/4 patients had DLTs of grade 4 neutropenia. Hypercalcemia was not observed. The RP2D of 1,25-D₃ was 60 mcg/m². Among 20 evaluable phase II patients, there were 2 confirmed, 4 unconfirmed partial responses (PR), and 9 stable disease (SD). Median time to progression was 5.8 months (95 % CI 3.4, 6.5), and median overall survival 8.7 months (95 % CI 7.6, 39.4). CYP24A1 SNP rs3787554 (C > T) correlated with disease progression (P = 0.03) and CYP24A1 SNP rs2762939 (C > G) trended toward PR/SD (P = 0.08). There was no association between 1,25-D₃ PK and CYP24A1 SNPs.

Conclusions

The RP2D of 1,25-D₃ with docetaxel and cisplatin was 60 mcg/m² every 21 days. Pre-specified endpoint of 50 % confirmed RR was not met in the phase II study. Functional SNPs in CYP24A1 may inform future studies individualizing 1,25-D₃.     

Intrathecal mafosfamide: a preclinical pharmacology and phase I trial.

PURPOSE: Preclinical studies of mafosfamide, a preactivated cyclophosphamide analog, were performed to define a tolerable and potentially active target concentration for intrathecal (IT) administration. A phase I and pharmacokinetic study of IT mafosfamide was performed to determine a dose for subsequent phase II trials. PATIENTS AND METHODS: In vitro cytotoxicity studies were performed in MCF-7, Molt-4, and rhabdomyosarcoma cell lines. Feasibility and pharmacokinetic studies were performed in nonhuman primates. These preclinical studies were followed by a phase I trial in patients with neoplastic meningitis. There were five dose levels ranging from 1 mg to 6.5 mg. Serial CSF samples were obtained for pharmacokinetic studies in a subset of patients with Ommaya reservoirs. RESULTS: The cytotoxic target exposure for mafosfamide was 10 micromol/L. Preclinical studies demonstrated that this concentration could be easily achieved in ventricular CSF after intraventricular dosing. In the phase I clinical trial, headache was the dose-limiting toxicity. Headache was ameliorated at 5 mg by prolonging the infusion rate to 20 minutes, but dose-limiting headache occurred at 6.5 mg dose with prolonged infusion. Ventricular CSF mafosfamide concentrations at 5 mg exceeded target cytotoxic concentrations after an intraventricular dose, but lumbar CSF concentrations 2 hours after the dose were less than 10 micromol/L. Therefore, a strategy to alternate dosing between the intralumbar and intraventricular routes was tested. Seven of 30 registrants who were assessable for response had a partial response, and six had stable disease. CONCLUSION: The recommended phase II dose for IT mafosfamide, administered without concomitant analgesia, is 5 mg over 20 minutes.     

Intrapleural cisplatin and mitomycin for malignant mesothelioma following pleurectomy: pharmacokinetic studies.

PURPOSE: Intrapleural cisplatin-based chemotherapy has been used in the treatment of patients with malignant pleural mesothelioma and malignant pleural effusions, but the pharmacokinetics of this form of chemotherapy have not been previously evaluated. We performed pharmacokinetic studies on 12 patients who received both intrapleural cisplatin and mitomycin immediately following pleurectomy/decortication for malignant pleural mesothelioma. PATIENTS AND METHODS: Simultaneous pleural fluid and plasma samples were collected at 15 and 30 minutes, and at 1, 2, 3, 4, and 24 hours after administration of the intrapleural chemotherapy (cisplatin 100 mg/m2 and mitomycin 8 mg/m2), and after cisplatin (total and free) and mitomycin levels were measured. The mean peak levels, the areas under the concentration-time curve (AUC) and the drug half-lives (t1/2s) in plasma and pleural fluid were compared using the paired t test. Differences were considered significant if P less than or equal to .05. RESULTS: Systemic absorption was rapid, with peak plasma levels being reached within 1 hour of administration of the intrapleural chemotherapy. Peak plasma levels measured after intrapleural chemotherapy approximated those reportedly attained during systemic administration of these drugs at similar doses. However, the mean peak cisplatin and mitomycin levels, and their mean AUCs, were significantly higher in the pleural fluid than in the plasma. There was a three- to fivefold advantage (on a logarithmic scale) for pleural to plasma AUCs for both cisplatin and mitomycin. The mean t1/2s for cisplatin and mitomycin were significantly longer in the plasma than in the pleural fluid. CONCLUSIONS: The pharmacokinetics of intrapleural cisplatin-based chemotherapy are analogous to those of intraperitoneal chemotherapy. Our findings show that intrapleural cisplatin-based chemotherapy has a distinct local pharmacologic advantage, but also produces significant and sustained drug plasma levels.     

A phase I clinical and pharmacokinetic study of paclitaxel and docetaxel given in combination in patients with solid tumours

The aim of this study was to determine the safety and feasibility profile of paclitaxel (PTX) and docetaxel (DTX) in combination and the pharmacokinetic and pharmacodynamic interaction between these two drugs in two different alternated sequences of administration. The starting dose was PTX (100 mg/m(2)) as a 3-h IV infusion followed by DTX (50 mg/m(2)) as 1-h IV infusion or the alternative sequence in every other patient. The sequence was alternated in the second course in each patient treated. Cycle duration was 21 days. Twenty patients received 103 cycles of treatment through three dose levels. Febrile neutropenia and grade 4 neutropenia lasting longer than 7 days were dose-limiting and defined the toxic dose of DTX (50 mg/m(2)) and PTX (135 mg/m(2)) in patients with prior treatment and the recommended dose in patients without prior treatment. Non-hematological toxicities included asthenia, neuropathy, arthralgia/myalgia and stomatitis. Pharmacokinetics of DTX were significantly affected by the sequence. Nadir ANC was more profound when DTX was administered first (P=0.022). There were one complete response and six partial responses, giving an overall response rate of 35%. DTX (50 mg/m(2)) followed by PTX (135 mg/m(2)) can be administered safely and it is an active regimen. The pharmacokinetics of PTX are not influenced by DTX but DTX pharmacokinetics depend on the sequence of administration, which influences its haematological toxicity profile.     

Clinical and pharmacokinetic phase I study of multitargeted antifolate (LY231514) in combination with cisplatin.

PURPOSE: Multitargeted antifolate (MTA; LY231514) has broad preclinical antitumor activity and inhibits a variety of intracellular enzymes involved in the folate pathways. This study was designed to (1) determine the maximum-tolerated dose (MTD), dose-limiting toxicities (DLT), and pharmacokinetics of MTA combined with cisplatin; (2) determine a recommended dose for phase II studies; and (3) collect anecdotal information on the antitumor activity of MTA combined with cisplatin. PATIENTS AND METHODS: Patients with solid tumors received MTA intravenously over 10 minutes and cisplatin over 2 hours once every 21 days. In cohort 1, both agents were administered on day 1 starting with MTA 300 mg/m(2) and cisplatin 60 mg/m(2). In cohort 2, MTA (500 or 600 mg/m(2)) was administered on day 1, followed by cisplatin (75 mg/m(2)) on day 2. RESULTS: In cohort 1, 40 assessable patients received 159 courses of treatment. The MTD was MTA 600 mg/m(2)/cisplatin 100 mg/m(2). DLTs were reversible leukopenia/neutropenia and delayed fatigue. Hydration before cisplatin therapy did not influence MTA pharmacokinetics. Eleven objective remissions included one complete response in a patient with relapsed squamous cell head and neck carcinoma, and partial responses in four of ten patients with epithelial pleural mesothelioma. In cohort 2, 11 assessable patients received 23 courses of treatment. The MTD was MTA 600 mg/m(2) and cisplatin 75 mg/m(2). DLTs were neutropenic sepsis, diarrhea, and skin toxicity. Two patients died of treatment-related complications during the study. Two patients had objective remissions (one mesothelioma patient, one colon cancer patient). CONCLUSION: The combination of MTA and cisplatin is clinically active, and administering both agents on day 1 is superior to a split schedule. Further development of this combination for mesothelioma is warranted.     

Open-label, phase I, pharmacokinetic studies of abiraterone acetate in healthy men

Purpose

To evaluate pharmacokinetics, safety, and tolerability of abiraterone acetate (AA) in healthy men.

Methods

Two phase I studies (dose-escalation study and dose-proportionality study) were conducted in healthy men aged 18–55?years. All subjects received 4 consecutive single doses of AA (250, 500, 750 and 1,000?mg). The dose-escalation study subjects (N?=?33) received AA doses in a sequential manner, starting with the lowest dose. The dose-proportionality study subjects (N?=?32) were randomly allocated (1:1:1:1) to receive each of the 4 doses in a four-way crossover design.

Results

A dose-related increase in abiraterone exposure was observed in both studies. Over the evaluated dose range, the mean abiraterone maximum plasma concentrations increased from 26 to 112?ng/mL in dose-escalation study and from 40 to 125?ng/mL in dose-proportionality study; the mean area under the plasma concentration–time curve from 0 to the last measurable plasma concentration increased from 155 to 610?ng.h/mL in dose-escalation study, and from 195 to 607?ng.h/mL in dose-proportionality study. In the dose-proportionality study, abiraterone exposure was dose proportional between 1,000 and 750?mg doses; however, the exposure was slightly greater than dose proportional when exposures at 500 and 250?mg doses were compared with the exposure at 1,000?mg. Single doses of AA were well tolerated in healthy men, and safety profile was consistent with its known toxicities in CRPC patients.

Conclusion

Systemic exposure to abiraterone increased with increasing doses of AA (250–1,000?mg) in healthy men; AA was well tolerated in this population.