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Biomedical subjects

R Sorio

Publications and source records attributed to R Sorio.

At least 19 recordsLinked to original sources

Innovative schedule of oral idarubicin in elderly patients with metastatic breast cancer: comprehensive results of a phase II multi-institutional study with pharmacokinetic drug monitoring.

BACKGROUND: To determine if protracted low-dose oral idarubicin (IDA), feasible in a previous dose-finding study, would result in similar activity and a better toxicity profile in patients with metastatic breast cancer. PATIENTS AND METHODS: Elderly women (> or=65 years) with metastatic breast carcinoma were treated with 7.5 mg/day for 21 consecutive days, every 4 weeks. After the first fourteen patients, due to excessive toxicity, the protocol was amended to 5 mg/day. IDA and Idarubicinol (IDOL) plasma concentrations (C(trough)) were investigated in all patients. RESULTS: Between April 1999 and June 2004, 47 elderly patients were accrued in this two-part study (14 and 33 patients respectively). The median age was 74 and 75 years respectively. Visceral involvement was present in most patients. A partial response was noted in 7/31 patients (22%; 95% CI, 9.6-41.1%). Eleven patients had stable disease (33%). At the dose of 5 mg/day the treatment was well tolerated. Neutropenia grade 4 was present in only 6% of patients; alopecia > grade 1 and cardiotoxicity did not occur. The median time to progression was 3 months and the median overall survival was 17 months. IDA C(trough) and IDOL C(trough) levels were significantly associated with haematologic toxicity. CONCLUSION: This study shows that idarubicin at the dose of 5 mg/day for 21 consecutive days is feasible and effective in elderly breast cancer patients but do not demonstrate an improvement in efficacy. A determination of the IDA and IDOL plasma levels (C(trough)) is predictive for toxicity.

Administration, Oral↗

Gemcitabine and anthracyclines in platinum-resistant ovarian cancer.

BACKGROUND: Most of the patients with advanced ovarian cancer will recur after first-line platinum-based chemotherapy and need additional treatment. Gemcitabine (G) and Anthracyclines are active in this setting and their combination has shown synergistic antiproliferative activity in vitro, due to different mechanisms of action and non-overlapping toxicities. PATIENTS AND METHODS: In 2002 we began a phase II study with G 1000 mg/m(2) (day 1,8) combined to Epirubicin (E) 60 mg/m(2) (day 1), every 3 weeks for 6 cycles, in Platinum resistant/refractory ovarian carcinoma patients. RESULTS: Among 30 patients enrolled so far (27 evaluable), receiving 149 cycles (median 6), 1 complete and 12 partial responses (48%), 9 stabilizations (33%) and 5 progressions (18%) were observed, with a good correlation with serological responses. Median time to progression was 8 months, while median time to response was 10 weeks and median duration 8 months. Grade 3-4 toxicities consisted of neutropenia (58%), thrombocytopenia (3%), anemia (10%), liver toxicity (13%), and mucositis (7%). Eight patients (27%) received G-CSF and 3 (10%) blood transfusions. No febrile neutropenia nor cardiotoxicity were observed. CONCLUSIONS: Although our results are preliminary, G/E combination appears particularly effective and safe in these platinum resistant/refractory patients.

Adult↗

Oral etoposide in elderly patients with advanced non small cell lung cancer: a clinical and pharmacological study.

Seventeen elderly patients with advanced progressive non small cell lung cancer (NSCLC) were treated with oral etoposide at the daily dose of 100 mg for 14 days every 3-4 weeks with pharmacokinetic monitoring. One partial response and 6 stabilizations were documented with a median overall duration of 13 weeks (range 8-32). The median survival was 24 weeks with an apparent advantage for non-progressive patients (40 weeks vs. 18 weeks). The treatment was well tolerated especially by those patients without concomitant illness, suggesting the crucial role of a careful selection of the geriatric population. Toxicity was not related to the etoposide plasma level, but was clearly dependent on comorbidity. A geriatric assessment rather than chronological age therefore appears to be more reliable in the selection of elderly patients for clinical trials. The easy self-management, favorable toxicity profile and synergy with other compounds makes oral etoposide suitable for further clinical-pharmacological studies in elderly patients.

Administration, Oral↗

A study from the EORTC new drug development group: open label phase II study of sabarubicin (MEN-10755) in patients with progressive hormone refractory prostate cancer.

Sabarubicin (MEN-10755), a new synthetic anthracycline analogue, was evaluated for safety and efficacy in a multicentre phase II study in patients with advanced hormone refractory prostate cancer (HRPC). Thirty seven patients were included, of which 34 were evaluable for PSA response according to Bubley's criteria. Sabarubicin was administered as a short (30 min) intravenous infusion at a dose of 80 mg/m(2) every 3 weeks. The main toxicity consisted of grade 3/4 neutropenia in 24 patients (64.9%), with grade 3/4 febrile neutropenia occurring in one patient only. Grade 3/4 cardiotoxicity was observed in 4 patients including one ineligible. Other toxicities were mild. Nine patients achieved a PSA response (26.5%), 10 patients had stable disease (29.4%) and 14 patients disease progression (41.2%). One patient (2.9%) had a PSA response that was not confirmed by repeat PSA testing. The objective response rate according to RECIST criteria was 6.7% in 15 patients with measurable disease. The median duration of PSA responses was relatively long 7.1 months (95% CI 4.9-20.7) as was the median time to treatment progression in patients with stable disease. The median overall survival was 18.7 months (95% CI 9.1-N), comparable to results recently observed in taxotere-containing regimens. To confirm and extend these results, further testing of sabarubicin in larger trials is warranted.

Aged↗

Pharmacokinetic comparison of 120-hour infusion versus hyperfractionated oral administration of idarubicin.

The aim of this study was to compare the pharmacokinetics of idarubicin (IDA) and its active metabolite idarubicinol (IDOL) after chronic oral and continuous intravenous (i.v.) IDA administration in order to establish the oral doses needed to reach the i.v. equiactive plasma drug exposure. The pharmacokinetic profile of IDA and IDOL was investigated in 23 patients receiving 12 mg/m2 IDA by 120-h i.v. infusion (2.4 mg/m2/day) combined with cyclophosphamide, etoposide and prednisone in comparison to 28 patients receiving oral IDA doses ranging from 2 to 10 mg/day for 21 days in a phase I study. We found that IDA AUC24h/dose/m2 was 4.7-fold greater during i.v. than oral administration, whereas IDOL AUC24h/dose/m2 was only about 2-fold higher after i.v. administration. The metabolic ratio between IDOL AUC24h and IDA AUC24h in plasma was about 3-fold higher after oral administration. Based on these results we were able to estimate that equiactive plasma drug exposure was reached with an approximately 2.5-fold greater oral dose/m2 of IDA than the corresponding i.v. dose.

Administration, Oral↗

Treatment of older breast cancer patients with high recurrence risk.

Adjuvant treatment of elderly women affected by breast cancer who have a high risk of recurrence is one of the most questionable issues in clinical oncology. The use of tamoxifen in women with hormone receptor-positive tumors is a relatively simple therapeutic option considering the favourable toxicity profile, whereas the administration of adjuvant chemotherapy is more complicated and a variety of aspects need to be considered. The estimated life expectancy, the presence and degree of comorbid conditions, the geriatric assessment and estimated benefit from treatment should be taken into account. Due to the lack of data from clinical trials in women over the age of 70, the approach is still experimental. Clinical trials evaluating the role of adjuvant chemotherapy in high risk patients are currently being developed and hopefully in the near future, more convincing data on the best drugs, regimens and benefits for the treatment of elderly breast cancer patients will become available.

Aged↗

Ifosfamide in advanced/disseminated breast cancer.

Ifosfamide is an alkylating agent active in various tumor types including breast cancer. The availability of mesna (sodium 2-mercaptoethanesulfonate) has increased its safety, avoiding the main dose-limiting side effect, urotoxicity. Interesting activity as a single agent, with response rates ranging from 7 to 30%, is reported in pretreated patients; more attractive data derived from phase II studies on ifosfamide combined with drugs known to be active in advanced breast cancer show response rates always over 35%. This review has taken in consideration papers published after 1995 and available on PubMed medline: the data indicate a potential usefulness of ifosfamide in the clinical management of advanced breast cancer, even if the exact therapeutic role of the drug in this setting should be derived from randomized studies not yet available.

Antineoplastic Agents, Alkylating↗

Phase II study of XR5000 (DACA) administered as a 120-h infusion in patients with recurrent glioblastoma multiforme.

BACKGROUND: XR5000 is a tricyclic carboxamide that intercalates DNA and inhibits both topoisomerase I and II. The aim of this study was to evaluate the efficacy and tolerability of XR5000 in patients with recurrent glioblastoma multiforme previously untreated with chemotherapy at relapse. PATIENTS AND METHODS: Patients received XR5000 at a dose of 3010 mg/m2 as a 120-h central venous infusion every 3 weeks. An independent panel assessed response every two cycles using McDonald's criteria (tumour size, steroid intake and neurological status); toxicity was graded according to the National Cancer Institute-Common Toxicity Criteria, version 2.0. RESULTS: Sixteen patients were enrolled (one ineligible patient was excluded from efficacy evaluation). Performance status was zero (five patients), one (nine patients) or two (one patient). They received 30 cycles of XR5000 (median 2, range 1-5). Haematological toxicity was mild, with only one patient experiencing grade 3 neutropenia. Other related grade 3/4 adverse events included chest pain (one patient), axillary vein thrombosis (one patient) and rigors/fever in the absence of neutropenia (one patient). There were no objective responses, 14 patients progressing on XR5000 and one having stable disease. CONCLUSIONS: Although XR5000 was generally well tolerated, these results do not support further evaluation in patients with glioblastoma multiforme using this dose and schedule.

Acridines↗

Phase II study of sequential administration of docetaxel followed by doxorubicin and cyclophosphamide as first-line chemotherapy in metastatic breast cancer.

PURPOSE: To evaluate the feasibility and efficacy of a sequential administration of four cycles of docetaxel (100 mg/m(2) every 3 weeks) followed by four cycles of doxorubicin and cyclophosphamide (AC; 60/600 mg/m(2) every 3 weeks), with subsequent consolidation with docetaxel or AC, as first-line chemotherapy in patients with metastatic breast cancer (MBC). PATIENTS AND METHODS: Forty-eight patients received 443 cycles of chemotherapy (median, 11 cycles/patient; range, 1 to 13 cycles). A total of 267 cycles of docetaxel (60.3%) and 176 of AC (39.7%) were given. Consolidation therapy was given to 33 patients (29 with docetaxel). RESULTS: Grade 4 neutropenia was the most frequent toxicity (83% of patients). This was not cumulative and was rarely complicated by febrile neutropenia or severe infection. The nonhematologic safety profile was favorable: there were no grade 4 adverse events, and grade 3 episodes were infrequent. Docetaxel-specific toxicities were generally not severe. With a median cumulative doxorubicin dose of 397 mg/m(2) (range, 150 to 543 mg/m(2)), two incidences of unrelated congestive heart failure after further treatment with anthracyclines and two of asymptomatic left ventricular ejection fraction decrease were observed. Among the 42 assessable patients, five (12%) had complete and 25 (60%) had partial responses, for an overall response rate of 71% (95% confidence interval, 55% to 84%). Median duration of response was 53 weeks (range, 12 to 72 weeks), and median time to progression was 46 weeks (range, 3 of 72 weeks). With a median follow-up of 40.4 months, median survival was 32 months (range, 2 to 55 months). CONCLUSION: This docetaxel-based sequential schedule is safe and effective in first-line therapy for MBC, without incurring cumulative toxicity, and provides a feasible chemotherapeutic option in this clinical setting.

Adult↗

Population pharmacokinetics and pharmacodynamics of oral etoposide.

AIMS: To study the population pharmacokinetics and pharmacodynamics of oral etoposide in patients with solid tumours. METHODS: A prospective, open label, cross-over, bioavailability study was performed in 50 adult patients with miscellaneous, advanced stage solid tumours, who were receiving oral (100 mg capsules) etoposide for 14 days and i.v. (50 mg) etoposide on day 1 or day 7 in randomised order during the first cycle treatment. Total and unbound etoposide concentration were assayed by h.p.l.c. Population PK parameters estimation was done by using the P-Pharm software (Simed). Haematological toxicity and tumour response were the main pharmacodynamic endpoints. RESULTS: Mean clearance was 1.14 l h(-1) (CV 25%). Creatinine clearance was the only covariable to significantly reduce clearance variability (residual CV 18%). (CL = 0.74 + 0.0057 CLCR; r(2) = 0.32). Mean bioavailability was 45% (CV 22%) and mean protein binding 91.5% (CV 5%). Exposure to free, pharmacologically active etoposide (free AUC p.o.) was highly variable (mean value 2.8 mg l(-1) h; CV 64%; range 0.4-9.5). It decreased with increased creatinine clearance and increased with age which accounted for 9% of the CV. Mean free AUC p.o. was the best predictor of neutropenia. Free AUC50 (exposure producing a 50% reduction in absolute neutrophil count) was 1.80 mg l(-1) h. In patients with lung cancer, the free AUC p.o. was higher in the two patients with responsive tumour (5.9 mg l(-1) h) than in patients with stable (2.1 mg l-1 h) or progressive disease (2.3 mg l-1 h) (P = 0.01). CONCLUSIONS: Exposure to free etoposide during prolonged oral treatment is highly variable and is the main determinant of pharmacodynamic effects. The population PK model based on creatinine clearance is poorly predictive of exposure. Therapeutic drug monitoring would be necessary for dose individualization or to study the relationship between exposure and antitumour effect.

Administration, Oral↗

Resistance to methotrexate in SKOV-3 cell lines after chronic exposure to carbamazepine is associated with a decreased expression of folate receptor.

The detrimental effect of chronic administration of carbamazepine (CBZ) on serum and erythrocyte folates of patients has been extensively analyzed. However, at present, no data have been reported on the effect of CBZ on the intracellular content and activity of antimetabolite cytotoxic agents that can be used together with CBZ in the treatment of cancer patients. To investigate this issue, we chronically exposed in vitro the human ovarian cancer cell line SKOV-3 (grown under physiological folate concentrations) to CBZ, thus selecting SKOV-CBZ clones (SKOV-CBZ-50-2, SKOV-CBZ-50-5 and SKOV-CBZ-100-2) able to grow in the continuous presence of the antiepileptic drug. All of the SKOV-CBZ clones were more resistant to methotrexate (MTX) than the parental cells. MTX resistance index, as determined by the ratio between MTX concentrations inhibiting cell growth by 50% (MTX IC(50)) in SKOV-CBZ clones and in the parental cells, ranged between 3- and 5-fold. This resistance was related to a reduced intracellular content of MTX. No alteration activity of the cellular enzymes directly involved in MTX cytotoxicity (dihydrofolate reductase, thymidylate synthase [TS] and folylpolyglutamate synthetase) was observed. SKOV-CBZ clones were cross-resistant to the TS inhibitors tomudex and CB3717, but not to the TS inhibitor 5-fluoro-deoxy uridine and other antineoplastic drugs (cisplatin, doxorubicin, vincristine and taxol), whose cellular uptake is derived from transmembrane transport mechanisms different from folate receptor alpha (FRalpha) or reduced folate carrier (RFC). FRalpha mRNA and protein levels were significantly lower in SKOV-CBZ clones than in the parental cells. The reduced level of FRalpha in SKOV-CBZ clones was associated with a decreased binding capacity of folic acid. No variation of mRNA RFC expression in the SKOV-CBZ clones as compared to the parental cells was observed. Thus, after chronic exposure to CBZ, SKOV-CBZ clones develop resistance towards MTX due to defective MTX uptake.

Biological Transport↗

Carzelesin phase II study in advanced breast, ovarian, colorectal, gastric, head and neck cancer, non-Hodgkin's lymphoma and malignant melanoma: a study of the EORTC early clinical studies group (ECSG).

PURPOSE: In a phase II trial, the activity of carzelesin, a cyclopropylpyrroloindole prodrug analog, was assessed. PATIENTS AND METHODS: Carzelesin was used as second- or third-line chemotherapy in patients with breast, ovarian, head and neck cancer and non-Hodgkin's lymphoma, and as first-line chemotherapy in patients with colorectal and gastric cancer and melanoma. The drug was given as a bolus infusion at a 4-weekly dose of 150 microg/m2. A total of 140 patients were entered and a total of 285 courses were administered. RESULTS: In general, the compound was well tolerated. Myelotoxicity was the most common toxicity. Grade 3 and 4 leukopenia was observed in 18.6% of the courses, neutropenia in 20.3%, thrombocytopenia in 16.2% and anemia in 8.7%. Double nadirs were seen in a total of 41 courses for neutrophils, in 40 for leukocytes and in 3 for platelets. Non-hematological toxicity was very mild. Only one partial response in a patient with melanoma was seen. CONCLUSIONS: At this dose and schedule carzelesin did not yield activity in the types of tumors studied.

Adult↗

Dose-finding and pharmacologic study of chronic oral idarubicin therapy in metastatic breast cancer patients.

Oral idarubicin (IDA) is an active drug in metastatic breast cancer, but its role in the management of this tumor is yet not established completely. To investigate a new modality of IDA administration, a dose-finding study was designed with hyperfractionated doses. The purpose was to determine the maximum tolerated dose (MTD), the dose-limiting toxicity (DLT), and the pharmacokinetics of this schedule. IDA was administered twice daily as outpatient therapy in cycles of 3 weeks followed by a 1-week rest. Thirty-one patients with progressive metastatic breast cancer and pretreated with chemotherapy (including epirubicin and doxorubicin) were enrolled. DLT was defined as G4 hematological toxicity or any other toxicity G3 or higher (Bloom and Richardson grading). Inter- and intrapatient dose increases were studied. Pharmacokinetics of IDA and its metabolite idarubicinol (IDOL) were evaluated. IDA dose was increased from 2 mg/day to 10 mg/day, by steps of 1 mg/day, with the larger dose given in the evening. MTD was reached at 10 mg/day. Overall, the therapy cycles were 69 (median/patient, 2; range, 1-6). DLTs were G4 neutropenia associated with leukopenia and thrombocytopenia in one patient and G3 diarrhea in another of the 5 patients in the 10 mg/day cohort. The two patients developing DLT at the daily dose of 10 mg received a dose normalized for body surface of 6.85 and 5.65 mg/m2/day, respectively. We considered 5.5 mg/m2/day to be the MTD. Other toxicities were nausea, vomiting, neutropenia, and diarrhea, grades G1 to G2. By univariate analysis, significant correlations were observed between absolute neutrophil count at nadir and IDA area under the curve (P = 0.022; r = -0.33), IDA Cmax (P = 0.0067; r = -0.38), IDOL area under the curve (P = 0.0009; r = -0.43), and IDOL Cmax (P = 0.0016; r = -0.41), respectively. By multivariate analysis, IDA Cmax was the strongest determinant for neutropenia (R2 = 0.14; P = 0.01). Among the 21 patients evaluable for response, 3 (14.3%) had partial response (lasting 3, 6, and 8 months, respectively), and 6 (28.6%) had a complete arrest of disease progression (lasting 2-6 months). In conclusion, the MTD of this schedule is 10 mg/day and the DLTs are neutropenia and diarrhea. Tolerance was good, and the treatment is feasible as home therapy. Some objective measurable responses were documented in this group of anthracycline-pretreated patients. IDOL could have a role for the pharmacological effect. Further evaluation of this schedule is warranted to assess the activity and toxicity of prolonged oral IDA administration.

Administration, Oral↗

Pharmacokinetics of oral etoposide in patients with hepatocellular carcinoma.

Etoposide dosage in patients with liver dysfunction remains controversial. Since etoposide has a hepatic component to its clearance (CL) and shows a high degree of protein binding, hepatic impairment could affect etoposide disposition. However, the empiric recommendation that the dose of etoposide be decreased in such patients may reduce systemic exposure and be detrimental to its antitumor activity. To address these issues we studied the pharmacokinetics (PK) of etoposide in patients with hepatocellular carcinoma (HCC) and underlying cirrhosis (n = 17) treated with daily oral etoposide. Unbound etoposide was obtained by ultrafiltration. Etoposide concentrations (total and free drug) were measured by high-performance liquid chromatography (HPLC) and analyzed by noncompartmental equations. The patients had mild or moderate liver dysfunction. Albuminemia was in the normal range for all the patients. Creatininemia was normal in all but two patients. PK results (mean and range) showed that etoposide disposition was unchanged in patients with liver dysfunction. We found slightly high etoposide bioavailability [F, 61% (17-95%)] and clearance [CL, 1.1 (0.7-2.3)l h(-1) m(-2)] resulting in a normal degree of systemic exposure (AUC(oral) 27 microg h ml(-1)). Normal protein binding [PB 93.2% (84.4-98.1%)] contributed to a normal level of exposure to free drug (AUC(f, oral) 1.9 microg h ml(-1)). The distribution volume [V(SS) 8.4 (6.1-13.2) l/m2] and the effective half-life [t1/2eff, 5.1 (3.0-9.6) h] were normal. Median CL and protein binding did not differ in the seven patients with total bilirubin value of > 1.2 mg/dl as compared with the ten patients with total bilirubin levels of < or = 1.2 mg/dl (1.3 versus 1.01 h(-1) m(-2) and 92.5% versus 93.4%, respectively). In agreement with this PK finding, we observed no clinical evidence of increased toxicity in patients with hyperbilirubinemia as compared with patients with normal bilirubinemia (mean WBC decrease 38% versus 47%). The only case of severe (grade 4) hematological toxicity was observed in one patient with reduced glomerular filtration. Since the pharmacological effects of etoposide correlate with the level of systemic exposure to the free drug, our data suggest that no dose reduction is needed in patients with HCC. It is even possible to increase the dose intensity in patients with favorable PK parameters under appropriate hematological and therapeutic drug monitoring.

Administration, Oral↗

Effect of cyclosporin A on protein binding of teniposide in cancer patients.

We investigated the effect of cyclosporin A (CSA) on protein binding of teniposide (VM26) in 16 patients with metastatic renal cell carcinoma receiving i.v. VM26 alone over 24 h (total dose, 200 mg/m2) and in association with CSA (5 mg/kg/2 h followed by 30 mg/kg/48 h i.v.). CSA was used in an attempt to overcome multidrug resistance. The unbound fraction (%fu) of VM26 was significantly (p=0.04) higher in the cycles with CSA (median 0.8; range 0.4-1.9) than in the cycles with VM26 alone (median 0.5; range 0.1-1.6). Both total VM26 area under curve concentration (AUC0-infinity) and free VM26 AUC0-infinity increased after treatment with CSA, but the median increase in free AUC0-infinity was higher (2.7-fold) than total AUC0-infinity (1.5-fold) (p = 0.04). Bilirubin was significantly (p<0.01) increased after CSA but no association was observed between bilirubin level and %fu of VM26. Albumin was in the normal range after both VM26 alone and VM26 plus CSA. The nadir of absolute neutrophil count (ANC) after VM26 plus CSA (median 700/microl, range <100-2860/microl) was lower than after VM26 alone (median 1900/microl, range 200-6000/microl) (p = 0.0007). The median percentage of ANC compared to the pretreatment value (ANC nadir/ANC pretreatment x 100) was 39.0% (range 3.1-98.8%) in the cycles with VM26 alone and 16.9% (range 1.4-97.9%) (p = 0.007) after VM26 plus CSA. Percentage change of neutrophils significantly correlated with free AUC0-infinity VM26 in the cycles with VM26 alone and VM26 plus CSA (p = 0.04, r = -0.53 and p = 0.04, r = -0.52, respectively). Only a trend which failed to reach significance was observed between total AUC0-infinity VM26 and percentage change of neutrophils in the cycles with VM26 alone and in association with CSA (p = NS, r = -0.33 and p = 0.055, r = -0.49, respectively). In conclusion, patients treated with CSA had higher systemic exposure to unbound VM26.

Adult↗

Pharmacokinetic interaction between etoposide and tamoxifen in patients with hepatocellular carcinoma.

The effect of tamoxifen (TAM) on the pharmacokinetics of oral administration of etoposide (VP-16) in patients with nonoperable hepatocellular carcinoma was investigated. The pharmacokinetics of VP-16 was studied by using a validated limited sampling strategy. The pharmacokinetic parameters of VP-16, such as area under curve (AUC), free AUC and protein binding, were determined from drug plasma concentrations at 1 and 4 h after VP-16 administration on the first day (day -1) and at the end of the chemotherapy cycle (day -21) for VP-16 alone and VP-16+TAM, respectively. When VP-16 was administered in association with TAM, the median total systemic exposure was not significantly (p = NS) different from that observed when VP-16 was administered alone [33.74 (range 11.19-56.58) versus 32.97 (range 20.23-119.28) mg/l/h]. Moreover, TAM did not affect significantly (p = NS) the levels of protein binding of VP-16 [median 94.6 (range 87.7-98.2) versus median 94.9 (range 91.6-98.0)% for VP-16+TAM and VP-16 alone, respectively] and the systemic exposure of the free drug (free AUC) [1.86 (range 0.21-4.57) versus median 1.78 (range 0.59-3.73) mg/l/h for VP-16+TAM and VP = 16 alone, respectively]. These results indicate a lack of pharmacokinetic interaction between VP-16 and TAM, and suggest that the increased hematological toxicity observed when TAM is given in combination with VP-16 could be related to pharmacodynamic interactions.

Aged↗