Carboplatin-based chemotherapy with pharmacokinetic analysis for patients with hemodialysis-dependent renal insufficiency

Summary Three patients with renal insufficiency requiring hemodialysis were treated with carboplatin at 100 mg/m² in combination with etoposide for advanced germ-cell tumor (GCT, two cases) or Adriamycin + vinblastine for a transitional-cell carcinoma of the ureter (one case). Hemodialysis was performed 24 h after the administration of carboplatin. Both patients with GCT achieved a complete response, and the patient with transitional-cell carcinoma of the ureter was inevaluable for response but his disease has not progressed. The dose of carboplatin was increased in one patient as renal function improved on therapy. In two patients, the pharmacokinetics of carboplatin were determined; the pre-dialysis half-lives, AUC, and total body clearances of free carboplatin-derived platinum were estimated to be 32 and 18.3 h, 4.93 and 6.17 mg ml^–1 min, and 18.2 and 18.7 ml/min, respectively. The dialysis elimination half-lives (t_1/2) of 2 and 3 h, respectively, for these two patients were markedly lower than the predialysis values, indicating that carboplatin was dialyzed. In summary, carboplatin can be given to patients with severe renal insufficiency. Adequate AUCs were achieved and dialysis limited systemic exposure to free carboplatin.Robert J. Motzer, M. D., is a recipient of an American Cancer Society Career Development Award     

Phase I and pharmacologic study of sequential topotecan-carboplatin-etoposide in patients with extensive stage small cell lung cancer

The inhibition of topoisomerase I by topotecan results in a compensatory increase in topoisomerase II associated with increased in vitro sensitivity of tumors to etoposide. Maximal synergy has been observed for the sequence of topotecan followed by etoposide. Carboplatin has clinical activity when combined with either of these two agents. These interactions were the pharmacologic rationale for topotecan p.o. days 1-5, carboplatin i.v. day 6, and etoposide p.o. days 6-10. Three successive dose levels were explored: (1) topotecan 2mg/day, carboplatin AUC 5, etoposide 150 mg/day; (2) topotecan 3mg/day, carboplatin AUC 5, etoposide 150 mg/day; and (3) topotecan 3mg/day, carboplatin AUC 5, etoposide 200mg/day. Filgrastim 5 microg/kg/day was injected s.c. days 11-18. Up to 6 cycles were administered every 21 days. Eligible patients had measurable or evaluable, extensive disease, small lung cell lung cancer, no prior chemotherapy, ECOG performance status 0-2, and adequate hematologic, renal, and hepatic function. Follow-up was weekly for CBC. Tumor response was assessed after 2 and 6 cycles. Dose limiting toxicity (DLT) was defined as any of the following in cycle 1: grade 3 or 4 non-hematologic toxicity other than nausea and vomiting, grade 4 neutropenia lasting more than 3 days, neutropenic fever or sepsis, grade 4 thrombocytopenia, or failure to recover neutrophils >or=1500/microl or platelets >or=100,000/microl by day 28. Ten patients were enrolled: median age 62 (range, 50-79); female/male 4/6; and performance status 0/1/2 in 2/7/1. Three patients each were treated on dose levels 1 and 2 without DLT. The first 2 patients entered on dose level 3 had no DLT. The third patient on dose level 3 developed grade 4 neutropenia lasting more than 3 days, neutropenic fever, and grade 4 thrombocytopenia on day 15 of cycle 1. The fourth patient on dose level 3 developed grade 4 thrombocytopenia on day 18 of cycle 1. One patient received only 1 cycle and was not evaluable for response. Seven patients completed 6 cycles: 1 had a complete response and 6 achieved a partial response. The third patient on dose level 3 received 2 cycles and had stable disease, but had to be removed from protocol treatment because of grade 4 neutropenia despite dose reduction in cycle 2. The fourth patient on dose level 3 achieved a partial response, but had to be removed from protocol therapy after cycle 5 because of recurrent grade 4 thrombocytopenia. In conclusion, neutropenia and thrombocytopenia were dose-limiting. The maximum tolerated dose (MTD) is topotecan 3mg/day p.o. days 1-5, carboplatin AUC 5i.v. day 6, and etoposide 150 mg/day p.o. days 6-10 with filgrastim.     

Carboplatin and etoposide pharmacokinetics in patients with testicular teratoma

Summary The pharmacokinetics of carboplatin and etoposide were studied in four testicular teratoma patients receiving four courses each of combination chemotherapy consisting of etoposide (120 mg/m² daily×3), bleomycin (30 mg weekly) and carboplatin. The carboplatin dose was calculated so as to achieve a constant area under the plasma concentration vs time curve (AUC) of 4.5 mg carboplatin/ml x min by using the formula: dose=4.5×(GFR+25), where GFR is the absolute glomerular filtration rate measured by ⁵¹Cr-EDTA clearance. Carboplatin was given on either day 1 or day 2 of each course and pharmacokinetic studies were carried out in each patient on two courses. Etoposide pharmacokinetics were also studied on two separate courses in each patient on the day on which carboplatin was given and on a day when etoposide was given alone. The pharmacokinetics of carboplatin were the same on both the first and second courses, on which studies were carried out with overall mean ± SD values (n=8) of 4.8±0.6 mg/ml x min, 94±21 min, 129±21 min, 20.1±5.41, 155±33 ml/min and 102±24 ml/min for the AUC, beta-phase half-life (t_1/2), mean residence time (MRT), volume of distribution (Vd) and total body (TCLR) and renal clearances (RCLR), respectively. The renal clearance of carboplatin was not significantly different from the GFR (132±32 ml/min). Etoposide pharmacokinetics were also the same on the two courses studied, with overall mean values ±SD (n=8) of: AUC=5.1±0.9 mg/ml x min, t_1/2=40±9 min, t_1/2=257±21 min, MRT=292±25 min, Vd=13.3±1.31, TCLR=46±9 ml/min and RCLR=17.6±6.3 ml/min when the drug was given alone and AUC=5.3±0.6 mg/ml x min, t_1/2=34±6 min, t_1/2=242±25 min, MRT=292±25 min, Vd=12.5±1.81, TCLR=43±6 ml/min and RCLR=13.4±3.5 ml/min when it was given in combination with carboplatin. Thus, the equation used to determine the carboplatin accurately predicted the AUC observed and the pharmacokinetics of etoposide were not altered by concurrent carboplatin administration. The therapeutic efficacy and toxicity of the carboplatin-etoposidebleomycin combination will be compared to those of cisplatin, etoposide and bleomycin in a randomised trial.     

A clinical and pharmacokinetic study of the combination of carboplatin and paclitaxel for epithelial ovarian cancer.

The aim of this phase I study was to determine the maximum tolerated dose of a 3-h infusion of paclitaxel, combined with carboplatin at a fixed AUC of 7 mg ml-1 min every 4 weeks for up to six cycles and to evaluate any possible pharmacokinetic interaction. Twelve chemonaive patients with ovarian cancer were treated with paclitaxel followed by a 30-min infusion of carboplatin. Paclitaxel dose was escalated from 150 mg m-2 to 225 mg m-2 in cohorts of three patients. Carboplatin dose was based on renal function. Pharmacokinetic studies were performed in nine patients (at least two at each dose level). A total of 66 courses were evaluable for assessment. Grade 3 or 4 neutropenia was seen in 70% of the courses, however hospitalization was not required. Grade 3 or 4 thrombocytopenia occurred in 24% of the courses. Alopecia, myalgia and peripheral neuropathy were common but rarely severe. The pharmacokinetics of paclitaxel was non-linear and did not appear to be influenced by co-administration of carboplatin. The AUC of carboplatin was 7.0 +/- 1.4 mg ml-1 min, indicating that there was no pharmacokinetic interaction. The combination of carboplatin and paclitaxel may be administered as first-line treatment for advanced ovarian cancer. Although myelosuppression is the dose-limiting toxicity of the component drugs, the severity of thrombocytopenia was less than anticipated. The results of this study, with only a small number of patients, need to be confirmed in future investigations.     

Changes in the clearance of total and unbound etoposide in patients with liver dysfunction

The disposition of total and non-protein-bound etoposide was investigated in 21 cancer patients receiving etoposide and cisplatin combination chemotherapy. Etoposide plasma concentrations were determined using a specific high-performance liquid chromatography (HPLC) method, and etoposide plasma protein binding was determined by equilibrium dialysis. The patients had a wide range of renal function (creatinine clearance, 32 to 159 mL/min/m2) and hepatic function (total bilirubin range, 0.3 to 21.5 mg/dL; aspartate aminotransferase [AST] range, 14 to 415 IU/L; serum albumin range, 2.7 to 4.1 g/dL). The mean etoposide total systemic clearance was not different in 15 patients with total bilirubin less than 1.0 mg/dL versus six patients with total bilirubin 1.1 to 21.5 mg/dL (18.7 +/- 5.9 mL/min/m2 v 26.4 +/- 10.7 mL/min/m2; t-test P = .06), with a trend toward higher total clearance in the patients with abnormal bilirubin values. However, the mean clearance of unbound etoposide was significantly lower in patients with increased total bilirubin (220 +/- 90 mL/min/m2 v 135 +/- 61 mL/min/m2; t-test P = .027). The fraction of etoposide unbound (fu) in plasma was significantly higher in patients with increased bilirubin (9% +/- 3% v 27% +/- 15%; t-test P = .002), explaining the trend toward higher total clearance in these patients. Etoposide clearance (total or unbound) in the 14 patients with measurable hepatic metastases was not different from the clearance in the seven patients without hepatic metastases. This study provides an explanation for why patients with increased bilirubin do not have lower total systemic clearance of etoposide, and indicates that such patients have a higher exposure to unbound etoposide. The results of ongoing pharmacodynamic studies of total and unbound etoposide in patients with increased bilirubin will determine the clinical relevance of altered etoposide protein binding.     

A multicentre phase II study of carboplatin and prolonged oral etoposide in the treatment of cancer of unknown primary site (CUPS).

Cisplatin-based combination chemotherapy is frequently used to treat patients with carcinoma of unknown primary site (CUPS). Response rates in the literature range from 12% to 26% and median survival from 5 to 7 months. The goal of this study was to evaluate the combination of carboplatin and prolonged oral etoposide in patients with CUPS, with the hope of minimizing toxicity but improving efficacy and convenience. Treatment consisted of carboplatin, 300 mg m(-2) on day 1, and oral etoposide 50 mg on days 1-20, every 4 weeks for up to nine cycles. A total of 33 patients were treated and all were evaluable for toxicity. Non-haematological toxicity was mild to moderate, with the exception of one case of grade 4 stomatitis. Grade 4 leucopenia was observed in eight (24%) patients and sepsis in four (12%), with two and possibly three treatment-related deaths. For the 26 patients evaluable for response, the response rate was 23% with responses lasting a median of 11 months (range 7-13 months), with one patient still responding at 12 months. An additional nine patients (35%) had stable disease. Median survival for all patients was 5.6 months (range 2 weeks to 33 months). The combination of carboplatin with prolonged oral etoposide has moderate activity similar to that of other platinum-based regimens and is a well tolerated, convenient, outpatient regimen. Dosing according to estimated creatinine clearance to achieve a carboplatin AUC of 6.0 mg ml(-1) min might have decreased the incidence of severe myelotoxicity without compromising the regimen''s efficacy.     

Phase II study of carboplatin and etoposide as a first line regimen in patients with metastatic breast cancer

BACKGROUND: The data available on the role of carboplatin and etoposidein breast cancer, especially in patients with no or minimalprior therapy are limited. PATIENTS AND METHODS: We performed a phase II study with carboplatin and etoposideas first line treatment in 34 patients with metastatic breastcancer. The treatment regimens was carboplatin 300 mg/m² day1, and etoposide 100 mg/m² days 1, 3 and 5, every four weeks. RESULTS: Of 33 evaluable patients, 2 achieved complete responses (6%)lasting 4 and 5 months, 7 patients (21%) achieved partial responseswith a median duration of 6+ (range 5–8) months, 15 patientshad stable disease, and 9 progressed during treatment. The majortoxicity was myelosuppression. WHO grades 3 or 4 leukocytopeniaor thrombocytopenia were seen in 15 and 10 patients, respectively.One formally ineligible patient with an impaired renal functiondied 14 days after the start of treatment because of a septicaemiain the presence of a grade 4 leukocytopenia. Besides this patientno other patient presented with granulo-cytopenic fever. CONCLUSIONS: In view of the observed response rate of 27% (95% confidenceinterval ll%–43%) we think that carboplatin and etoposidegiven in this dose and schedule has probably no clear advantageover the more commonly used regimens. metastatic breast cancer, chemotherapy, carboplatin, etoposide     

Sequential dose-intensive paclitaxel, ifosfamide, carboplatin, and etoposide salvage therapy for germ cell tumor patients.

PURPOSE: To evaluate the efficacy and toxicity of sequential, dose-intensified chemotherapy with paclitaxel/ifosfamide and carboplatin/etoposide administered plus peripheral blood-derived stem-cell (PBSC) support for patients with germ cell tumors (GCT) who have unfavorable prognostic features in response to conventional-dose salvage programs. Carboplatin was dose escalated by target area under the curve (AUC; in [milligrams per milliliter] x minutes) among patient cohorts, and pharmacokinetic studies were performed for comparison. PATIENTS AND METHODS: Thirty-seven previously treated patients who had cisplatin-resistant GCT and unfavorable prognostic features for response to conventional-dose salvage therapy were treated. Two cycles of paclitaxel 200 mg/m(2) plus ifosfamide 6 g/m(2) were given 2 weeks apart with leukapheresis, followed by three cycles of carboplatin plus etoposide given 14 to 21 days apart with reinfusion of PBSCs. The dose of etoposide was 1, 200 mg/m(2), and the carboplatin target AUC ranged among cohorts from 12 to 32 (mg/mL) x min. Pharmacokinetic studies of carboplatin were performed for comparison of target to measured AUC. RESULTS: Twenty-one patients (57%) achieved a complete response and an additional two patients (5%) achieved a partial response with normal tumor markers; therefore, 23 (62%) achieved a favorable response. Eight patients relapsed, and 15 (41%) of the favorable responses remained durable at a median follow-up of 30 months. Myelosuppression was the major toxicity; 58% of carboplatin/etoposide cycles were associated with hospitalization for nadir fever. The AUC of carboplatin measured in serum was lower than the target AUC; this may be related to underestimation of the glomerular filtration rate used in the dosing formula. CONCLUSION: Dose-intense therapy with sequential, accelerated chemotherapy of paclitaxel/ifosfamide and carboplatin/etoposide administered with PBSC support was relatively well tolerated. The durable complete response proportion was substantial in patients with unfavorable prognostic features for achieving durable complete response to conventional-dose salvage programs. Optimal dosing of carboplatin in the high-dose setting warrants further investigation.     

Phase I and pharmacologic study of sequential topotecan, carboplatin, and etoposide

Inhibition of topoisomerase I by topotecan results in a compensatory increase in topoisomerase II levels associated with increased in vitro sensitivity of tumors to etoposide. Maximum synergy has been observed for the sequence of topotecan followed by etoposide. This is the pharmacologic rationale for the sequence of topotecan 0.4 mg/m(2) per day for 7 days continuous i.v. infusion, carboplatin i.v. on day 8, and etoposide 50 mg per day p.o. days 9 through 20. The carboplatin dosage was escalated from an AUC of 4 to 5 to 6 (Calvert formula). Up to six treatment cycles were administered at 28-day intervals. Eligible patients had metastatic non-small cell lung cancer (NSCLC) or extensive disease small lung cell lung cancer (SCLC), no prior chemotherapy, performance status 0-2, and adequate organ function. Follow-up was twice weekly in the first cycle for CBC and for topotecan and etoposide concentrations. Follow-up, thereafter, was weekly. Tumor response was assessed after two and six cycles and then as clinically indicated. At carboplatin AUCs of 4 and 5, no NCI grade 4 toxicity was observed in cycle 1 in cohorts of three patients each. At the AUC of 5, two patients experienced dose-limiting events after cycle 3, one grade 4 neutropenia lasting >3 days (no fever) and one failure to recover an absolute neutrophil count >1500/microl by day 35. This was, therefore, deemed the maximal tolerable dose. Number of treatment cycles per patient ranged between 1 and 6, and three patients completed six cycles. All patients were male, age 47-71, with NSCLC in one and SCLC in six. The patient with NSCLC had progressive disease after one cycle. One complete and three partial responses were observed in five patients with SCLC. Mean steady-state plasma concentrations during topotecan infusion ranged from 0.73 to 1.69 ng/ml, and mean etoposide concentrations ranged from 60 to 230 ng/ml. This sequence of topotecan, carboplatin, and etoposide appeared tolerable and active. Neutropenia was the dose-limiting toxicity.     

Platinum-DNA adduct formation in leucocytes of children in relation to pharmacokinetics after cisplatin and carboplatin therapy.

Platinum (Pt)-DNA adducts were measured in peripheral blood leucocytes (PBLs) from 24 children with solid tumours after standard cisplatin and/or carboplatin treatment. The relationship between Pt-DNA adduct levels and pharmacokinetics of cisplatin and carboplatin was investigated. Adduct measurements were performed by competitive enzyme-linked immunosorbent assay (ELISA) and plasma unbound Pt concentrations were measured by atomic absorption spectrophotometry (AAS). There was considerable interindividual variation in Pt-DNA adduct level that was weakly correlated (r2 = 0.32) with the area under the unbound drug concentration vs time curve (AUC) at 6 h after the start of cisplatin infusion, indicating that the variation in Pt-DNA adduct levels was primarily determined by factors other than AUC. No clear relationship between AUC and adduct levels was seen at 24 and 48 h after cisplatin or at 6, 24 or 48 h after carboplatin. Carboplatin produced lower levels of immunoreactive adducts than did cisplatin (1.3 +/- 0.6 nmol Pt g-1 DNA vs 3.2 +/- 1.7 nmol Pt g-1 DNA), despite a 20-fold higher unbound drug AUC for carboplatin (8.0 +/- 3.5 mg ml-1 min vs 0.4 +/- 0.2 mg ml-1 min). This study demonstrates that, after cisplatin and carboplatin treatment the drug-target interaction is determined by both pharmacokinetic and, predominantly, cellular factors. Intrinsic differences between the two complexes, primarily reactivity, probably explain the lower adduct levels observed after carboplatin treatment.     

Conversion of the prodrug etoposide phosphate to etoposide in gastric juice and bile.

Etoposide phosphate is a water-soluble prodrug of etoposide. It was expected that this prodrug could be used to overcome the solubility limitations and erratic bioavailability of oral etoposide. To investigate the possibility of prodrug conversion to etoposide within the gastrointestinal lumen, etoposide phosphate was dissolved in water and incubated with human gastric juice or human bile in vitro. Samples were collected during 150 min and analysed for etoposide concentration with high-performance liquid chromatography. Conversion of prodrug to etoposide during incubation with gastric juice was negligible. There was significant conversion during incubation with bile at pH 7-8. The percentage of prodrug converted to etoposide at pH 8 after 60 min was 78 +/- 18% (mean +/- S.D.) for a 0.1 mg ml-1 prodrug solution and 36 +/- 26% for 0.5 mg ml-1. At pH 7, after 60 min 22% of prodrug was converted to etoposide when incubated at 0.1 mg ml-1 and 10% at 0.5 mg ml-1. No conversion was found after inactivation of alkaline phosphate (AP) by overnight heating of bile at 65 degrees C or by the addition of disodium edetate to the bile. In conclusion, because of AP in bile, variable conversion of etoposide phosphate to etoposide can be expected within the intestinal lumen after oral administration. This could have important pharmacokinetic consequences.     

Phase I trial of fixed dose-rate gemcitabine in combination with carboplatin in chemonaive advanced non-small-cell lung cancer: a Cancer Therapeutics Research Group study

PURPOSE: To determine the maximally tolerated dose (MTD) of gemcitabine administered at a fixed dose-rate of 10 mg/m(2) per min in combination with fixed dose carboplatin, to evaluate the toxicity of this regimen and to determine the pharmacokinetics of plasma gemcitabine. METHODS: Patients with advanced stage non-small-cell lung cancer (NSCLC) received carboplatin (AUC 5) on day 1 followed by gemcitabine at a fixed dose rate of 10 mg/m(2) per min in escalating durations of infusion on days 1 and 8 every 21 days. Pharmacokinetic sampling was obtained on day 1, cycle 1 of treatment. RESULTS: A total of 15 patients received carboplatin and gemcitabine in cohorts of three to six patients at three dose levels. The doses of gemcitabine studied were 600, 750, and 900 mg/m(2). The MTD was reached at 900 mg/m(2). Dose-limiting toxicities were thrombocytopenia and liver failure, and with repeated dosing neutropenia was commonly observed. The recommended phase II dose of gemcitabine was 750 mg/m(2). Partial responses were observed at 600 and 750 mg/m(2) of gemcitabine. Plasma gemcitabine did not reach steady state except in one patient with the durations of infusion studied. Plasma concentrations, however, were above 10 micro mol/l between 20 and 90 min in all patients. CONCLUSIONS: Gemcitabine administered as a 75-min infusion at a fixed dose rate of 10 mg/m(2)/min on days 1 and 8 in combination with carboplatin on day 1 every 21 days is tolerable and active in NSCLC. Pharmacokinetic studies demonstrated that the target plasma gemcitabine concentration above 10 micro mol/l was achieved. Further studies are warranted to compare this regimen against standard regimens of carboplatin and gemcitabine.     

Dose-escalation Study of Oral Etoposide and Carboplatin in Patients with Advanced Lung Cancer

A dose-escalation study of daily etoposide and carboplatin wascarried out on 23 patients with advanced lung cancer using astarting dose of 40 mg/m²/day etoposide given orally for 21days and 250 mg/m² carboplatin given intravenously (IV) on day1. A total of 41 courses were given. Myelosuppression was themajor dose-limiting toxicity. The maximum tolerated dose wasreached at the fourth level with 40 mg/m²/day etoposide for21 days and 400 mg/m² carboplatin on day 1, once every 4 weeks.Non-hematological toxicities were generally mild or reversible.The recommended doses of this combination chemotherapy are 40mg/m²/day etoposide for 21 days and 350 mg/m² carboplatin onday 1. The response rate for non-small cell lung cancer andsmall cell lung cancer was 16.7% and 60% (95% confidence intervalsof 3.6% to 41.4%, and 14.7% to 94.7%), respectively. A phaseII study is necessary to define the efficacy and safety of thiscombination chemotherapy.     

Phase I study of G3139, a bcl-2 antisense oligonucleotide, combined with carboplatin and etoposide in patients with small-cell lung cancer.

PURPOSE: Bcl-2 is expressed in the majority of cases of small cell lung cancer (SCLC) and may contribute to chemotherapeutic resistance. Bcl-2 suppression by G3139 (oblimersen sodium), a phosphorothioate oligonucleotide complementary to the bcl-2 mRNA, has the potential to enhance the antitumor efficacy of standard cytotoxic chemotherapy. A dose-finding study was performed evaluating the combination of G3139, carboplatin, and etoposide in patients with previously untreated extensive stage SCLC. PATIENTS AND METHODS: Sixteen patients were treated in three consecutive cohorts. Cohort 1 (n=5) received G3139 5 mg/kg/d on days 1 to 8 of a 21 day cycle, with carboplatin area under the curve (AUC)=6 on day 6, and etoposide 80 mg/m2/d on days 6 to 8. In cohort 2 (n=4), carboplatin dose was reduced to AUC=5. In cohort 3 (n=7), G3139 dose was escalated to 7 mg/kg/d. G3139 plasma concentrations and Bcl-2 protein levels in peripheral blood mononuclear cells were evaluated. RESULTS: Two of three assessable patients in cohort 1 experienced cycle 1 dose-limiting toxicity (grade 4 neutropenia). No cycle 1 dose-limited toxicity was observed in cohorts 2 or 3. Of 14 patients assessable for response, partial response was documented in 12 patients (86%), and stable disease in two. Median time to progression was 5.9 months. Carboplatin and etoposide administration did not appear to alter G3139 pharmacokinetics. No evidence of Bcl-2 suppression in peripheral blood mononuclear cells was observed. CONCLUSION: The combination of G3139, carboplatin, and etoposide is well tolerated and results in an encouraging response rate and time to progression in patients with extensive stage SCLC.     

Renal function after ifosfamide, carboplatin and etoposide (ICE) chemotherapy, nephrectomy and radiotherapy in children with Wilms tumour

We prospectively evaluated tumour response and renal function in 12 newly diagnosed children with high-risk Wilms tumour receiving ifosfamide, carboplatin and etoposide (ICE) chemotherapy. Two cycles of ICE were followed by 5 weeks of vincristine, dactinomycin and doxorubicin (Adriamycin) (VDA), and nephrectomy, radiotherapy, additional VDA, and a third ICE cycle. Carboplatin dosage was based on glomerular filtration rate (GFR) to achieve targeted systemic exposure (6mg/ml min). Mean GFR (measured by technetium 99m-DTPA clearance) declined by 7% after 2 cycles of ICE and by 38% after nephrectomy; the mean carboplatin dose was reduced 32% after nephrectomy. Mean GFR remained stable after the third ICE cycle. Although urinary beta(2)-microglobulin excretion increased during therapy, no patient had clinically significant renal tubular dysfunction at the end of treatment. Treatment with ICE, nephrectomy and radiotherapy significantly reduces GFR, largely as the result of nephrectomy. Adjustment of carboplatin dosage on the basis of GFR and careful monitoring of renal function may alleviate nephrotoxicity.     

Continuous ambulatory peritoneal dialysis: pharmacokinetics and clinical outcome of paclitaxel and carboplatin treatment

PURPOSE: Administration of chemotherapy in patients with renal failure, treated with hemodialysis or continuous ambulatory peritoneal dialysis (CAPD) is still a challenge and literature data is scarce. Here we present a case study of a patient on CAPD, treated with weekly and three-weekly paclitaxel/carboplatin for recurrent ovarian cancer. EXPERIMENTAL: During the first, second and ninth cycle of treatment, blood, urine and CAPD samples were collected for pharmacokinetic analysis of paclitaxel and total and unbound carboplatin-derived platinum. RESULTS: Treatment was well tolerated by the patient. No excessive toxicity was observed and at the end of treatment she was in a complete remission. The plasma pharmacokinetics of paclitaxel were unaltered compared to historical data, with neglectable urinary and CAPD clearance. In contrast, the pharmacokinetics of carboplatin were altered, with doubled half-lives compared to patients with normal renal function. Of the administered carboplatin dose, up to 20% was cleared via the dialysate, while only up to 8% was cleared via the urine. CONCLUSION: Paclitaxel and carboplatin can be safely administered to patients with chronic renal failure on CAPD. For paclitaxel the generally applied dose can be administered, and although for carboplatin dose-adjustment is required due to the diminished renal function, the dose can be calculated using Calvert's formula.     

High-dose ifosfamide,carboplatin, and etoposide pharmacokinetics: correlation of plasma drug levels with renal toxicity

An autologous bone marrow transplant regimen of ifosfamide, carboplatin, and etoposide (ICE) has been developed as treatment for certain malignancies. At maximum tolerated doses renal insufficiency precludes dose escalation. The objective was to examine whether measurement of plasma drug levels early during treatment would provide warning of renal failure. Nine patients received a 96-h continuous infusion of ifosfamide 16000 mg/m², carboplatin 1600 mg/m², and etoposide 1200 mg/m². Pharmacokinetics, including drug levels and plasma concentration-time curves, of ifosfamide, ultrafiltrable platinum (uPt) and etoposide were analyzed and correlated with renal function. One of the nine patients developed anuric renal failure requiring hemodialysis. By 17 h from the start of infusion, this patient showed substantially higher drug levels of ifosfamide (200 vs mean 217 M) and uPt (19 vs mean 10M) than those patients with preserved renal function. The 95% confidence intervals suggested that a 16–22 h ifosfamide level >153 M and an uPt level >M predict the development of significant renal dysfunction. Although drug levels were substantially higher at 56 h, the serum creatinine did not yet reflect kidney injury. This study suggests that high plasma ifosfamide and uPt levels, analyzed early in the course of a 96-h infusion of high-dose ICE, provide warning of severe and potentially fatal renal injury. Since ICE has substantial activity in a number of malignancies, but significant renal morbidity, real-time pharmacokineticguided dosing may reduce treatment-related toxicity.Supported in part by US. Public Health Service Grants PO1-CA-38493 and CA-06516 and a grant from the Mathers Foundation. Drs. Ayash and Schwartz are recipients of a Career Development Award from the American Cancer Society     

Pharmacokinetic analysis of combination chemotherapy with carboplatin and etoposide in small-cell lung cancer patients undergoing hemodialysis.

BACKGROUND: The aim of this study was to use pharmacokinetic analysis to investigate the efficacy and toxicity of combined chemotherapy with carboplatin (CBDCA) and etoposide (ETP) in small-cell lung cancer (SCLC) patients with chronic renal failure undergoing hemodialysis (HD). PATIENTS AND METHODS: Three SCLC patients with chronic renal failure undergoing HD were treated with CBDCA (300 mg/m(2)) on day 1 and ETP (50 mg/m(2)) on days 1 and 3, followed by HD 1 h after completing the administration of anticancer agents on each day. The pharmacokinetic analysis of CBDCA and ETP was planned for at least the first two courses of the chemotherapy in each patient. RESULTS: Two complete responses and one partial response were achieved in the three patients. Two patients experienced grade 3/4 neutropenia and required blood transfusion due to thrombocytopenia and anemia. Non-hematological toxicities were moderate. The pharmacokinetic analysis revealed that the platinum and the ETP concentrations in the plasma were similar to those in patients with normal renal function during the first 24 h, while the platinum still remained in the plasma for over 90 h. CONCLUSIONS: Chemotherapy with CBDCA (300 mg/m(2) on day 1) and ETP (50 mg/m(2) on day 1, 3) as used in the present study may be a suitable regimen for SCLC patients undergoing HD, although careful attention should be given to hematological toxicities.     

Phase I dose-finding and pharmacokinetic study of paclitaxel and carboplatin with oral valspodar in patients with advanced solid tumors.

PURPOSE: To evaluate the maximum-tolerated dose (MTD), dose-limiting toxicities (DLTs), and pharmacokinetic (PK) profile of paclitaxel and carboplatin when administered every 3 weeks with the oral semisynthetic cyclosporine analog valspodar (PSC 833), an inhibitor of P-glycoprotein function. PATIENTS AND METHODS: Fifty-eight patients were treated with escalating doses of paclitaxel ranging from 54 to 94.5 mg/m(2) and carboplatin area under the plasma concentration versus time curve (AUC) ranging from 6 to 9 mg.min/mL, every 21 days. The dose of valspodar was fixed at 5 mg/kg every 6 hours for a total of 12 doses from day 0 to day 3. The MTD was determined for the following two groups: (1) previously treated patients, where paclitaxel and carboplatin doses were escalated; and (2) chemotherapy-na?ve patients, where paclitaxel dose was escalated and carboplatin AUC was fixed at 6 mg.min/mL. PK studies of paclitaxel and carboplatin were performed on day 1 of course 1. RESULTS: Fifty-eight patients were treated with 186 courses of paclitaxel, carboplatin, and valspodar. Neutropenia, thrombocytopenia, and hepatic transaminase elevations were DLTs. In previously treated patients, no DLTs occurred at the first dose level (paclitaxel 54 mg/m(2) and carboplatin AUC 6 mg.min/mL). However, one of 12, two of six, two of four, four of 11, and two of five patients experienced DLTs at doses of paclitaxel (mg/m(2))/carboplatin AUC (mg.min/mL) of 67.5/6, 81/6, 94.5/6, 67. 5/7.5, and 67.5/9, respectively. In chemotherapy-na?ve patients, one of 17 developed DLT at paclitaxel 81 mg/m(2) and carboplatin AUC 6 mg/mL.min. There was prolongation of the terminal phase of paclitaxel elimination as evidenced by an increased time that plasma paclitaxel concentration was >/= 0.05 micromol/L, ranging from 16.6 +/- 6.7 hours to 41.5 +/- 9.8 hours for paclitaxel doses of 54.5 mg/m(2) to 94.5 mg/m(2), respectively. CONCLUSION: The recommended phase II dose in chemotherapy-na?ve patients is paclitaxel 81 mg/m(2), carboplatin AUC 6 mg.min/mL, and valspodar 5 mg/kg every 6 hours. In previously treated patients, the recommended phase II dose is paclitaxel 67.5 mg/m(2), carboplatin AUC 6 mg.min/mL, and valspodar 5 mg/kg every 6 hours. The acceptable toxicity profile supports the rationale for performing disease-directed evaluations of paclitaxel, carboplatin and valspodar on the schedule evaluated in this study.