Combination phase I/II study of irinotecan hydrochloride (CPT-11) and carboplatin in relapsed or refractory non-Hodgkin's lymphoma. CPT-11/Lymphoma Study Group

Irinotecan hydrochloride (CPT-11) is a new derivative of camptothecin which inhibits topoisomerase I. Phase II studies have demonstrated that CPT-11 is active against a broad spectrum of neoplasms including intractable non-Hodgkin's lymphoma. An early phase II study in lymphoma suggested that a schedule of daily infusions of 40 mg/m2/day for three or five consecutive days is more effective than a single infusion of 200 mg/m2 every three to four weeks. Carboplatin is also an active agent against lymphoma, and preclinical studies have shown that CPT-11 and its active metabolite have a synergistic effect with platinum compounds. To evaluate the maximal tolerated dose (MTD) and the therapeutic efficacy of CPT-11 in combination with carboplatin in relapsed or refractory non-Hodgkin's lymphoma, we conducted a combination phase I/II study. The starting dose of CPT-11 was 20 mg/m2/day (days 1 through 3 and 8 through 10), and dose escalations of 5 mg/m2/day increments were planned, with a fixed dose of carboplatin (300 mg/m2, day 1). Six of the eight patients receiving both agents at the starting dose level developed critical toxicities such as grade 4 hematologic (neutropenia 6/8, thrombocytopenia 1/8) and grade 3 non-hematologic toxicities (diarrhea 2/8, transaminase elevation 1/8). Further dose escalation of CPT-11 was halted, and the starting doses were judged to be the MTDs. The response rate (25%, 2/8) to the combination of the MTDs was not superior to that of CPT-11 alone in a previous phase II study (38%, 26/69), and the MTD of CPT-11 in combination with carboplatin was less than half the single-agent dose. We conclude that carboplatin is not recommendable for combination with CPT-11 in lymphoma patients. Other suitable agents for such a combination should be sought.     

Scaling of movement velocity: a measure of neuromotor retardation in individuals with psychopathology

The combination of ifosfamide, carboplatin and etoposide (modified ICE), was evaluated for its toxicity and activity in relapsed or refractory aggressive non-Hodgkin's lymphoma. Twenty patients, 14-69 years of age, with relapsed (19 cases) or refractory (one case) aggressive non-Hodgkin's lymphoma were treated with modified ICE therapy, consisting of ifosfamide 6 g/m2 (1.2 g/m2 day 1-5), carboplatin 400 mg/m2 (day 1) and etoposide 500 mg/m2 (100 mg/m2 day 1-5). The regimen was repeated at approximately 28-day intervals. All patients had undergone a doxorubicin-containing regimen before modified ICE therapy. Median total dose of previously received doxorubicin was 406 mg/m2 (range: 200-825 mg/m2). The median interval from diagnosis to modified ICE therapy was 9.4 months (range: 3.6-121 months). Two patients achieved CR and five achieved PR out of 16 patients with measurable lesions (response rate 43.8%; 95% confidence interval 19.0-68.6%). Median overall survival was 227 days (range: 41-552 days) from the start of modified ICE therapy. Myelosuppression was the most serious toxicity, namely 16 patients (80%) and 11 patients (55%) showed grade 4 neutropenia and grade 4 thrombocytopenia after the first course, respectively. Modified ICE therapy might be an active regimen with acceptable toxicity as a salvage chemotherapy in aggressive non-Hodgkin's lymphoma.     

Determinants of CPT-11 and SN-38 activities in human lung cancer cells

Irinotecan (CPT-11) is a semisynthetic camptothecin derivative with a broad spectrum of anti-tumour activity. Carboxylesterase (CE) catalyses the conversion of CPT-11 to SN-38 (7-ethyl-10-hydroxycamptothecin), the active form of CPT-11. The antiproliferative effects of CPT-11 and SN-38, CE-activity and topoisomerase I protein expression were investigated in five human small-cell lung cancer (SCLC) cell lines and four human non-small-cell lung cancer (NSCLC) cell lines. Antiproliferative activity, expressed as IC50 values, was determined using the MTT assay. CPT-11 was significantly more active in SCLC than in NSCLC cell lines (P = 0.0036), whereas no significant difference between histological types was observed with SN-38. A significant correlation (r2 = 0.52, P = 0.028) was observed between CE activity and chemosensitivity to CPT-11 but not to SN-38, and significantly higher CE activity was observed in SCLC compared with NSCLC cell lines (P = 0.025). Western blotting experiments showed topoisomerase I protein expressions within a factor of 2, and a granular nuclear staining was detectable in all cell lines by immunocytochemistry of cytospins. No correlation was observed between protein expression and sensitivity to CPT-11 or SN-38. Cellular and medium concentrations of CPT-11 and SN-38 were measured by high-performance liquid chromatography (HPLC) in one SCLC cell line with high CE activity and high sensitivity to CPT-11, and one NSCLC cell line with low sensitivity to CPT-11 and CE activity. Intracellular concentrations of CPT-11 and SN-38 were higher in the SCLC cell line, and this was associated with an increase in cellular uptake of CPT-11 compared with the medium, and an increased intracellular formation of SN-38. In conclusion, CE activity appears to be associated with higher sensitivity to CPT-11 in human lung cancer cell lines and may partly explain the difference in the in vitro sensitivity to CPT-11 between SCLC and NSCLC cells. The assessment of CE activity in clinical material of lung cancer patients undergoing treatment with CPT-11 may be warranted. However, other mechanisms may influence sensitivity to CPT-11, possibly including drug transport.     

Platelet integrin alpha IIb beta 3 (GPIIb-IIIa) is not implicated in the binding of LDL to intact resting platelets

The anti-tumor activity of irinotecan (CPT-11), a DNA-topoisomerase 1 inhibitor, was evaluated in 5 advanced stage subcutaneous medulloblastoma xenografts in nude mice, using different schedules of administration. With a 5-day schedule, the highest i.v. dose tested (40 mg kg-1 day-1) induced complete regressions in all xenografts but 1, and delays in tumor growth always exceeded 30 days. Two xenografts, IGRM11 and IGRM33, were highly sensitive, and animals survived tumor-free beyond 120 days after treatment. CPT-11 clearly retained its anti-tumor activity at a lower dosage (27 mg kg-1 day-1). CPT-11 was significantly more active than cyclophosphamide, thiotepa and etoposide against the 3 xenografts evaluated. To study the schedule dependency of its anti-tumor activity, CPT-11 was given i.v. at the same total doses over the same period (33 days) using either a protracted or a sequential schedule in IGRM34-bearing mice. With a dose of 10 mg kg-1 day-1 given on days 0-4, days 7-11, days 21-25 and days 28-32 (total dose, 200 mg kg-1), 3 of 6 animals were tumor free on day 378. The same total dose given with a sequential schedule, i.e., 20 mg kg-1 day-1 on days 0-4 and days 28-32, failed to induce complete regression. The plasma pharmacokinetics of CPT-11 and SN-38 were studied in IGRM34-bearing animals after a single i.v. dose of 10 and 40 mg kg-1. The plasma clearance rate of CPT-11 was dose dependent. The ratio between the SN-38 and CPT-11 area under the curve in plasma was 0.4-0.65, i.e., significantly higher than that observed in humans at the maximum tolerated dose (0.01-0.05). Conversely, this ratio was 10-fold lower in tumor than in plasma. Clinical development of irinotecan is warranted in pediatric malignancies.     

The relationship between AIDS dementia complex and the presence of macrophage tropic and non-syncytium inducing isolates of human immunodeficiency virus type 1 in the cerebrospinal fluid

CPT-11 is a camptothecin derivative with a broad spectrum of antitumor activity, both in vitro and in vivo. Like camptothecin, CPT-11 is a selective DNA topoisomerase I inhibitor. Phase I trials were conducted in Europe to determine the dose and schedule for phase II trials. These phase I trials assessed the toxicity of CPT-11 in 235 patients and tested three administration schedules: a single infusion once every 3 weeks; a weekly infusion for 3 out of 4 weeks; and a daily infusion for 3 consecutive days every 3 weeks. The maximum tolerated dose (MTD) was 115 mg/m2 in the daily schedule and 145 mg/m2 in the weekly schedule. When the drug was administered once every 3 weeks, diarrhea became the dose-limiting toxicity at doses above 350 mg/m2. This schedule offered the highest dose intensity and the best tolerability profile, and was the most convenient for outpatient treatment. Finally, using this schedule, concomitant administration of high-dose loperamide allowed the dose of CPT-11 to be increased to 750 mg/m2. An ongoing phase I trial is investigating the combination of CPT-11 and 5-fluorouracil (5-FU) in various solid tumors. Although the MTD has not yet been reached, preliminary results show no pharmacokinetic interaction between the two drugs, contrary to a previous Japanese study. Based on the results of the three phase I trials, CPT-11 350 mg/m2 as an intravenous infusion over 30 minutes once every 3 weeks was recommended for phase II trials, which started in Europe in 1992. To date, CPT-11 has shown remarkable efficacy in colorectal cancer, even in patients resistant to 5-FU. Interesting results have also been obtained in pancreatic, cervical and lung cancers. Future trials will explore the place of CPT-11 in combination with other cytotoxic agents or radiotherapy.     

Pathophysiology and therapy of irinotecan-induced delayed-onset diarrhea in patients with advanced colorectal cancer: a prospective assessment

PURPOSE: Irinotecan (CPT-11), a camptothecin derivative, has shown efficacy against colorectal cancer. Delayed-onset diarrhea is its main limiting toxicity. The aim of this study was to determine the pathophysiology of CPT-11-induced delayed-onset diarrhea and assess the efficacy of combined antidiarrheal medication in a phase II, prospective, successive-cohorts, open study. PATIENTS AND METHODS: Twenty-eight patients with advanced colorectal cancer refractory to fluorouracil (5-FU) therapy received CPT-11 350 mg/m2 every 3 weeks. The first cohort of 14 consecutive patients explored for the mechanism of diarrhea received acetorphan (a new enkephalinase inhibitor) 100 mg three times daily; the second 14-patient cohort received, in addition to acetorphan, loperamide 4 mg three times daily. Before treatment, and if late diarrhea occurred, patients underwent colon mucosal biopsies for CPT-11 and topoisomerase I levels; intestinal transit time; fecalogram; fat and protein excretion; alpha1-antitrypsin clearance; D-xylose test; blood levels for vasoactive intestinal polypeptide, glucagon, gastrin, somatostatin, prostaglandin E2, and carboxylesterase; CPT-11/SN-38 and SN-38 glucuronide pharmacokinetics; and stool cultures. RESULTS: Delayed-onset diarrhea occurred during the first three treatment cycles in 23 patients (82%). Electrolyte fecal measurements showed a negative or small osmotic gap in nine of nine patients and an increased alpha1-antitrypsin clearance in six of six patients. There were no modifications in stool cultures or hormonal dysfunction. Four of 11 patients (36%) with delayed-onset diarrhea in the first cohort responded to acetorphan, whereas nine of 10 patients (90%) responded to the combination of acetorphan and loperamide (P < .02). CONCLUSION: CPT-11-induced delayed-onset diarrhea is caused by a secretory mechanism with an exudative component. Early combined treatment with loperamide and acetorphan seems effective in controlling the diarrheal episodes.     

Identification and properties of a major plasma metabolite of irinotecan (CPT-11) isolated from the plasma of patients

Irinotecan [7-ethyl-10-[4-(1-piperidino)-1-piperidino]carbonyloxycamptothecin (CPT-11)] is a promising water-soluble analogue of camptothecin [S. Sawada et al., Chem. & Pharm. Bull. (Tokyo), 39: 1446-1454, 1991]. We have reported previously the presence of an important polar metabolite, in addition to 7-ethyl-10-hydroxycamptothecin (SN-38) beta-glucuronide, in samples of plasma taken from patients undergoing treatment with CPT-11 (L.P. Rivory and J. Robert, Cancer Chemother. Pharmacol. 36: 176-179, 1995; L. P. Rivory and J. Robert, J. Cromatogr., 661: 133-141, 1994). Plasma samples (0.5 ml) containing comparatively large amounts of this metabolite were extracted by solid-phase columns and subjected to high-performance liquid chromatography and mass spectrometry in parallel to fluorometric detection. The metabolite yielded [M + 1] ions with a m/z of 619, representing the addition of 32 atomic mass units to CPT-11. Purified fractions were subjected to proton nuclear magnetic resonance, and the structure determined, 7-ethyl-10-[4-N-(5-aminopentanoic acid)-1-piperidino]carbonyloxycampothecin (APC), was further validated following synthesis. Like CPT-11, APC was found to be only a weak inhibitor of the cell growth of KB cells in culture (IC50, 2.1 versus 5.5 micrograms/ml for CPT-11 and 0.01 microgram/ml for SN-38, the active metabolite of CPT-11) and was a poor inducer of topoisomerase I DNA-cleavable complexes (100-fold less potent than SN-38). In contrast to CPT-11, APC was not hydrolyzed to SN-38 by human liver microsomes or purified human liver carboxylesterase. Furthermore, APC did not inhibit the hydrolysis of CPT-11 in these preparations. Interestingly, APC was only a weak inhibitor of acetylcholinesterase in comparison to CPT-11 and neostigmine. It appears likely, therefore, that APC does not contribute directly to the activity and toxicity profile of CPT-11 in vivo.     

Successful treatment with CPT-11 and adriamycin for hemophagocytic syndrome associated with intravascular lymphomatosis

A 75-year-old man was admitted because of non-Hodgkin's lymphoma (histology undetermined) of the rib. A complete remission was achieved after CHOP therapy and irradiation. One year later, high fever, thrombocytopenia and liver dysfunction developed. Bone marrow aspirate revealed a hypoplastic marrow with hemophagocytic histiocytes, and a diagnosis of hemophagocytic syndrome (HPS) was made. Although no lymphomatous lesions were detected, HPS due to relapsed lymphoma was strongly suspected. The patient received MEVP therapy including etoposide and prednisolone, but without any improvement. Soon after the initiation of CPT-11 and adriamycin (ADM) therapy, all symptoms of HPS disappeared. This combination chemotherapy was repeated over a three-week span, and the patient remained in partial remission for the next 10 months. In November 1997, a tumor developed in the paranasal sinus, and the patient died three months later. The autopsy disclosed many B lymphoma cells filling the small vessels of almost all organs, and a final diagnosis of intravascular lymphomatosis (IVL) was made. These findings indicate that combination CPT-11 and ADM therapy is effective for cases of IVL accompanied by HPS that are refractory to conventional chemotherapies.     

Purification and characterization of human sarcomeric mitochondrial creatine kinase

PURPOSE: A dose-escalation study of irinotecan hydrochloride (CPT-11) combined with fixed-dose cisplatin was conducted to determine the maximum-tolerated dose (MTD), dose-limiting toxicities, and objective response rate in patients with advanced gastric cancer. PATIENTS AND METHODS: Twenty-four patients with or without prior chemotherapy were enrolled. All patients were assessable for toxicities and response. On day 1, CPT-11 was administered as a 90-minute intravenous (I.V.) infusion, which was followed 2 hours later by a 120-minute I.V. infusion of cisplatin 80 mg/m2. CPT-11 alone at the same dose was administered again on day 15. The treatment was repeated every 4 weeks until disease progression was observed. The initial dose of CPT-11 was 60 mg/m2, and was escalated in increments of 10 mg/m2 until severe or life-threatening toxicity was observed. RESULTS: The MTD of this combination was CPT-11 80 mg/m2. At this dose level, 16.7% of patients (two of 12) had leukopenia of less than 1,000/microL, 66.7% (eight of 12) had neutropenia of less than 500/microL, and 16.7% (two of 12) had severe diarrhea of grade 4 during the first course. The dose-limiting toxicity was neutropenia. Ten patients achieved a partial response (PR), and the overall response rate was 41.7% among 24 patients (95% confidence interval, 21.9% to 61.4%). CONCLUSION: The recommended dose and schedule is CPT-11 70 mg/m2 on days 1 and 15 and cisplatin 80 mg/m2 on day 1 every 4 weeks. This combination of CPT-11 and cisplatin, considered to be active against advanced gastric cancer with acceptable toxicity, should be further assessed in a phase II study.     

Adjuvant immunotoxin therapy with anti-B4-blocked ricin after autologous bone marrow transplantation for patients with B-cell non-Hodgkin's lymphoma

Anti-B-blocked ricin (anti-B4-bR) combines the specificity of the anti-B4 (CD19) monoclonal antibody with the protein toxin "blocked ricin." In blocked ricin, affinity ligands are attached to the ricin B-chain to attenuate its lectin binding capacity. In a phase I trial, Anti-B4-bR was administered by 7-day continuous infusion to 12 patients in complete remission after autologous bone marrow transplantation (ABMT) for relapsed B-cell non-Hodgkin's lymphoma (NHL). Patients were treated at 20, 40, and 50 micrograms/kg/d for 7 days. Potentially therapeutic serum levels could be sustained for 3 to 4 days. The maximum tolerated dose was 40 micrograms/kg/d for 7 days (total 280 micrograms/kg). The dose-limiting toxicities were reversible grade IV thrombocytopenia and elevation of hepatic transaminases. Mild capillary leak syndrome was manifested by hypoalbuminemia, peripheral edema (4 patients), and dyspnea (1 patient). Anti-immunotoxin antibodies developed in 7 patients. Eleven patients remain in complete remission between 13 and 26 months post-ABMT (median 17 months). These results show that Anti-B4-bR can be administered with tolerable, reversible toxicities to patients with B-cell NHL in complete remission following ABMT.     

Epidural analgesia and uterine rupture during labour

Intravenous-bolus etoposide has modest activity in sarcomas when given daily for 3-5 days. Low frequent doses theoretically inhibit topoisomerase II activity over a longer duration and have been reported to have increased activity in small-cell lung cancer. A phase I trial of oral etoposide resulted in partial responses in two patients with soft-tissue sarcomas. To estimate more accurately the response rate for daily oral etoposide in sarcomas, we treated 25 patients with 50 mg/m2 per day by mouth for 21 days every 4 weeks. Treatment-related toxicity included > or = grade 2 neutropenia in 6 of the 25 patients and thrombocytopenia in 3. One brief partial response was observed (4%; 95% confidence interval for true response rate, 0-11%). Disease stabilized in five patients for periods ranging from 3 to 18 months. At this dose and on this schedule, daily oral etoposide appears to have little activity against soft-tissue sarcomas.     

The MACOP-B and VACOP-B combination chemotherapy for young patients with intermediate-grade non-Hodgkin's lymphoma

Since the early 1970s, three generations of combination chemotherapy for intermediate-grade non-Hodgkin's lymphomas (NHL) have been developed. One of the third-generation regimens is MACOP-B (methotrexate, doxorubicin, cyclophosphamide, vincristine, prednisone, and bleomycin). The VACOP-B regimen is a modification of MACOP-B in which methotrexate is omitted and etoposide is added. This study assesses treatment outcome using the MACOP-B and VACOP-B combination chemotherapy in a population of young patients with intermediate-grade NHL treated in a single tertiary hematological center. The files of 45 patients aged 18-55 who were diagnosed as having intermediate-grade NHL (working formulation types F-H) and treated between January 1986 and March 1994 were reviewed. Treatment response, overall survival, disease-free survival and treatment toxicity were determined. The predictive value of the age-adjusted international prognostic index was also assessed. Median follow-up was 80 months in the MACOP-B group and 29 months in the VACOP-B group. The complete response rate was 71% (95% confidence interval CI: 58-84), 4-year overall survival was 74 +/- 7% and 4-year disease-free survival was 79 +/- 8%. No toxicity-related deaths were observed. The main adverse effects were WHO grade 3 or 4 neutropenia (51%), anemia (24%) and mucositis (20%). Only the CR rate was correlated with the Age-Adjusted International Prognostic Index. Mean relative dose intensity was high (95.7%, 95%) CI: 91.7-99.7) and had no correlation with treatment outcome. The MACOP-B and VACOP-B combination chemotherapy regimens were found to be effective and minimally toxic for young patients up to 55 years old with intermediate-grade NHL.     

Phase I clinical and pharmacologic study of weekly cisplatin combined with weekly irinotecan in patients with advanced solid tumors

PURPOSE: In vitro synergy between cisplatin and irinotecan (CPT-11) has been reported. We designed a combination schedule of these agents to maximize the potential for synergistic interaction. PATIENTS AND METHODS: To maximize the opportunity for synergy, we divided the cisplatin into four consecutive weekly treatments, followed by a 2-week rest. Each dose of cisplatin was immediately followed by a dose of irinotecan. The dose of cisplatin was fixed at 30 mg/m2/wk. The initial irinotecan dose was 50 mg/m2/wk and this was escalated by 30% increments in successive cohorts of three to six patients to establish the maximum-tolerated dose (MTD). Pharmacokinetics of irinotecan and its metabolites, SN-38 and SN-38 glucuronide (SN-38G), were analyzed. RESULTS: Of 35 patients with solid tumors enrolled onto this trial, 30 were assessable for toxicity and response. The MTD for this regimen was 30 mg/m2/wk of cisplatin plus 50 mg/m2/wk of irinotecan in previously treated patients and 30 mg/m2/wk of cisplatin plus 65 mg/m2/wk of irinotecan in chemotherapy-naive patients. Neutropenia was the dose-limiting toxicity (DLT) encountered in this trial. Diarrhea was infrequent and rarely dose-limiting. Seven of 30 assessable patients achieved a partial response. No alteration in irinotecan, SN-38, or SN-38G pharmacokinetics resulted from the administration of cisplatin with irinotecan. CONCLUSION: The administration of cisplatin and irinotecan on this weekly schedule provides a practical and well-tolerated regimen that has the potential to maximize any clinical synergy between the two agents. Evidence of substantial clinical activity was seen in this phase I study.     

Hypercalciuria

BACKGROUND: Second- and third-generation chemotherapy protocols for the treatment of aggressive non-Hodgkin's lymphomas (NHL) have considerable, and age-related, toxic effects. In addition, they do not seem to prolong overall survival in comparison to standard CHOP chemotherapy. In this phase II study we investigated the feasibility and efficacy of the addition of etoposide to the conventional CHOP regimen. PATIENTS AND METHODS: Toxicity and clinical efficacy were determined in 132 patients with previously untreated high-grade NHL. There were 51 patients in clinical stage I and II and 81 patients in stage III and IV, with a median age of 54 years (range 17-85). Patients received standard-dose CHOP plus etoposide 100 mg/m2 i.v. on day 1 and 200 mg/m2 p.o. on days 2-3. RESULTS: The overall response rate was 84%, with 70% complete and 14% partial responses. The predicted three- and five-year survivals for the group as a whole were 60% and 53%, respectively, and the corresponding disease-free survivals for patients achieving complete remissions were 65% and 56%, respectively. Outcome was not different from that of CHOP-treated patients in a recently completed Nordic study performed during the same time period. Myelosuppression (WHO grade 3-4), observed in 87% of patients and infectious complications (WHO grade 3-4) in 33%, dominated the toxicity profile of this regimen. Fifty-seven of 92 complete responders (62%) received 6-8 CHOP-E cycles with no reductions in planned dose intensity. LDH level higher than normal, extranodal sites = 2, stage III-IV at diagnosis were all indicators of a poor survival. CONCLUSIONS: We conclude that CHOP-E treatment is effective in high-grade NHL. However, mainly due to severe myelosuppression frequent schedule modifications were required and the results are not obviously superior to those of conventional CHOP.     

Low-grade mucoepidermoid carcinoma on the vermilion border of the lip

BACKGROUND AND PURPOSE: CPT-11 (7-ethyl-10-[4-(1-piperidino)-1-piperidino] carbonyloxycamptothecin) is anew semisynthesized derivative of camptothecin. SN-38 (7-ethyl-10-hydroxycamptothecin), a metabolite of CPT-11, plays a key role in the action of CPT-11. MATERIALS AND METHODS: To determine whether SN-38 potentiates the cytotoxic effect of radiation, we investigated the interaction of SN-38 and radiation in vitro in monolayer cultures and multicellular spheroids of HT-29 human colon adenocarcinoma cells. RESULTS: HT-29 spheroids were more resistant to both SN-38 and irradiation than monolayer cells. SN-38 at a concentration of 2.5 microg/ml, which by itself was not cytotoxic, greatly increased the lethal effects of radiation in spheroids, but not in monolayer cultures. Exposure to SN-38 following irradiation inhibited the potentially lethal damage repair (PLDR) in spheroids. It is suggested that the mechanism of the radiosensitization by SN-38 is due to the PLDR inhibition. CONCLUSIONS: These results indicate that CPT-11 may play a role as radiosensitizer and that a combination of CPT-11 and irradiation could prove to be a particularly effective strategy with which to treat human colon adenocarcinoma.     

The evaluation of eustachian tube function in patients with chronic otitis media

To assess the clinical usefulness of salivary monitoring of irinotecan (CPT-11) and its active metabolite (SN-38), we examined the clinical pharmacological profile of both drugs in 9 patients with thoracic malignancies who received 60 mg/m2 CPT-11 (21 courses). Plasma and unstimulated whole saliva were collected over a 24-h period, and concentrations of CPT-11 and SN-38 were measured by high-performance liquid chromatography. Both CPT-11 and SN-38 were detectable in saliva, and the concentration-time curves in plasma and saliva showed a very similar pattern. A good correlation was observed between the saliva concentration (C3) and the plasma concentration (Cp) for both CPT-11 and SN-38 (r = 0.732, P < 0.0001 and r = 0.611, P < 0.0001, respectively). The area under the concentration-time curve calculated for saliva (AUCs) correlated with that generated for plasma (AUCp) for both CPT-11 and SN-38 (r = 0.531, P = 0.012 and r = 0.611, P = 0.0025, respectively). These results suggest that it may be feasible to use saliva instead of plasma for pharmacokinetics/pharmacodynamics studies of CPT-11.     

Effect of prostaglandin A1 on proliferation and telomerase activity of human melanoma cells in vitro

BACKGROUND AND OBJECTIVE: Idarubicin, an anthracycline analogue, is active in non-Hodgkin's lymphoma. This study evaluates the efficacy and toxicity of a combination of idarubicin, etoposide and intermediate-dose cytarabine (IVA) in unfavorable lymphoma in relapse or resistant to prior doxorubicin- or novantrone-based regimens. DESIGN AND METHODS: Thirty patients with relapsing or resistant unfavorable lymphoma received a combination of idarubicin 12 mg/m2 i.v. on day 1, etoposide 60 mg/m2 i.v. every 12 hours for 3 days, and Ara-C 1 g/m2 i.v. every 12 hours for 3 days (3-hour infusion). Median age was 39 years (range: 22-60). All patients had been given prior doxorubicin or novantrone; 54% of them had received 2 or more chemotherapy regimens; 67% of total were in clinical relapse (30% in their second relapse), and 23% had resistant disease. RESULTS: The overall response rate to IVA was 60% (18 of 30 patients). Complete remission rate was 20% (6 of 30) in the whole group, 45% (5 of 11) among patients in their first relapse. Remission median duration was 9 months (range: 1-18), with a 3-year relapse-free and overall survival of 20% and 15%, respectively. Severe neutropenia occurred in 13 patients (43%) and severe thrombocytopenia in 11 patients (37%), with a median duration of 9 and 13 days, respectively. No cardiac toxicity developed; sepsis during neutropenia was documented in four instances and two patients (7%) died of therapy-related events (septic shock). INTERPRETATION AND CONCLUSIONS: Idarubicin combined with etoposide and intermediate-dose cytarabine proved to be an active salvage therapy in unfavorable lymphoma given prior doxorubicin or novantrone; the best results were obtained among patients in their first relapse, with low tumor burden.     

In vitro activity of trovafloxacin in combination with ceftazidime, meropenem, and amikacin

There are few reports on chemotherapy of non-Hodgkin's lymphoma (NHL) in patients with chronic renal failure. Two long-term hemodialysis patients were treated for NHL with modified CHOP therapy. The plasma pharmacokinetics of adriamycin (ADR) and etoposide (VP-16) were investigated in these patients. In the first case, NHL was diagnosed in a 37-year-old male (diffuse pleomorphic, T cell type, stage I E). After 4 courses of chemotherapy, he achieved complete remission. The second case, was a 56-year-old male who was admitted to our hospital with melena and abdominal pain. A diagnosis of NHL (diffuse mixed, B cell type, stage III E) was made. Complete remission was achieved with 2 courses of chemotherapy. Levels of hematological and neurological toxicity were moderately severe but tolerable. Pharmacokinetics of ADR and VP-16 in these patients were similar to those in patients with normal renal function. These results suggested that ADR and VP-16 were effective drugs for hemodialysis patients with NHL.     

Plasma pharmacokinetics of 7-ethyl-10-hydroxycamptothecin (SN-38) after intravenous administration of SN-38 and irinotecan (CPT-11) to rats

We studied the plasma pharmacokinetics of the lactone form and the carboxylate form of 7-ethyl-10-hydroxycamptothecin (SN-38), the active metabolite of irinotecan (CPT-11), after intravenous bolus administrations of each form of SN-38 and of CPT-11 to rats. After the SN-38 lactone injection, SN-38 lactone was predominant at first, and then the lactone to the carboxylate concentration ratio (LC ratio) was maintained from 30 to 90 min after the injection. The carboxylate was predominant throughout the period after the carboxylate dosing. Model-dependent analyses showed that the SN-38 lactone had greater plasma clearance and a greater distribution volume than the carboxylate. The CPT-11 administration resulted in a predominant plasma SN-38 lactone concentration. The contribution of the SN-38 lactone AUC to the total SN-38 AUC (57%) was independent of the dose of CPT-11. These results suggest that it is possible to estimate the SN-38 lactone concentration and AUC from the total SN-38 concentration without separate determination of the lactone and carboxylate. Our results showed that both SN-38 lactone and CPT-11 administration gave the predominant SN-38 lactone in plasma; however, only CPT-11 could sustain the lactone concentration at a high level, which is necessary for antitumor activity.     

Limited sampling model for the area under the concentration versus time curve of irinotecan and its application to a multicentric phase II trial

We previously established a limited sampling model (LSM) for the area under the concentration versus time curve (AUC) of irinotecan (CPT-11). Using this LSM, we performed a pharmacokinetic-pharmacodynamic analysis of CPT-11 in a multicentric Phase II study for non-small cell lung cancer. Ten institutes participated in this study, 36 patients were registered, and 30 patients were evaluable for the pharmacokinetic-pharmacodynamic analysis. CPT-11 and etoposide were administered daily for three consecutive days, both at a dose of 60 mg/m2. Blood samples were obtained 4 and 8 h after infusion on days 1 and 3. When using the LSM, there is a significant possible source of error in the timing of these selected points. In this study, however, the sample timing error was small. Mean timing errors were 1.0-4.0 min at each point. The estimated CPT-11 AUCs were: Day 1 Day 2 Day 1 + 3 Mean +/- SD (mg.h/liter) 3.76+/-0.68 4.10+/-0.86 7.86+/-1.43 Range 2.01-5.03 2. 29-5.72 4.30-10.68 Max/min 2.50 2.45 2.48 High interpatient variability was observed in the AUC. The CPT-11 AUC correlated positively with the grade of emesis (P = 0.003) and the percent decreases in WBC count (P = 0.001) and absolute neutrophil count (P =0.0006), but it did not correlate with the grade of diarrhea or response. We concluded that the LSM was useful in estimating individual pharmacokinetic parameters in multicentric trials.