High-dose cisplatin in hypertonic saline: reduced toxicity of a modified dose schedule and correlation with plasma pharmacokinetics. A Northern California Oncology Group Pilot Study in non-small-cell lung cancer

Clinical course and risk factors of neurotoxicity following cisplatin in an intensive dosing schedule

An intensive weekly regimen of cisplatin was administered to 66 patients with solid cancer in doses varying from 70 to 85 mg/m(2) . The occurrence of sensory neuropathy was prospectively examined by assessment of neuropathic signs and symptoms and measurement of vibration perception threshold (VPT). Evaluation was performed before initiation of therapy and during follow-up until 3-12 months after the last cycle of cisplatin. A mild or moderate neuropathy developed in 47% of patients at 2 weeks after treatment This neuropathy continued to deteriorate until approximately 3 months after cessation of chemotherapy leading to a mild or moderate neuropathy in 71% of patients and a severe neuropathy in 9% of patients. Thereafter we observed a gradual but incomplete recovery. The high incidence of neuropathy we found may be explained by the prolonged observation period compared with earlier reports. The only factor correlated with severity of neuropathy was the cumulative dose of cisplatin, while there was no association with either pre-treatment VPT, age, sex, tumor type or co-treatment with etoposide. The progressing course up to approximately 3 months after the end of treatment underscores the need for prolonged follow-up in future studies on cisplatin neuropathy.-

Concurrent weekly cisplatin chemotherapy and radiotherapy in a haemodialysis patient with locally advanced cervix cancer

AIMS

Concurrent cisplatin chemo-radiotherapy improves outcome in cervical carcinoma. In haemodialysis patients, cisplatin is potentially hazardous. We report the treatment of a haemodialysis patient with cervix cancer using cisplatin-based chemo-radiation. Mathematical modelling using toxicity data from a range of cisplatin dosages and schedules reported in published studies was undertaken.

MATERIALS AND METHODS

The patient was treated using weekly cisplatin chemotherapy 25mg/m(2). The serum platinum levels were measured. Correlations between reported toxicity and platinum levels for a variety of cisplatin schedules in published studies were evaluated.

RESULTS

Treatment was completed with no interruptions and minimum acute toxicity. The platinum levels rose progressively. The elimination half-life was prolonged at 6.6-7.5 days. The percentage extraction varied between 7.7 and 41.0%. The cumulative cisplatin dose correlated with neurotoxicity (P=0.002). Myelotoxicity correlated with the peak cisplatin level in the first 15 days of treatment (P=0.01). With an elimination half-life of 7.5 days, 35 mg/m(2) weekly is predicted to have the same risk of myelotoxicity and neurotoxicity as 40 mg/m(2) weekly in a patient with normal renal function.

CONCLUSIONS

Weekly cisplatin chemotherapy 25mg/m(2) can be delivered safely in a haemodialysis patient. Dialysis is effective in eliminating platinum even if carried out more than 3h after infusion, but it should commence as soon as possible after cisplatin infusion, as the incidence of myelotoxicity is related to the peak platinum level.

Continuous or repeated prolonged cisplatin infusions in children: a prospective study on ototoxicity, platinum concentrations, and standard serum parameters

BACKGROUND

To overcome the ototoxicity of cisplatin, single bolus infusions were replaced by repeated prolonged infusions of lower doses or by continuous infusions at still lower infusion rates. However, considering ototoxicity little is, in fact, known about the tolerance of repeated prolonged or continuous infusion in children.

PROCEDURE

Auditory function was monitored along with plasma concentrations of free and total platinum (Pt), and with standard serum parameters (sodium, potassium, calcium, magnesium, phosphate, chloride, and creatinine) in 24 children receiving cisplatin by continuous infusion for the treatment of neuroblastoma and osteosarcoma or by repeated 1 or 6 hr infusions for the treatment of germ cell tumors.

RESULTS

Hearing deteriorated in 10/15 osteosarcoma patients, 2/3 neuroblastoma patients, and 1/6 patients with germ cell tumors. Ototoxicity occurred after cumulative doses between 120 and 360 mg/m(2) cisplatin. In osteosarcoma patients, ototoxicity was associated with a comparatively higher mean plasma concentration of free Pt. However, Pt plasma concentrations did not discriminate between patients with or without ototoxicity. In patients experiencing ototoxicity serum creatinine increased by 45% compared to pre-treatment levels (mean). Serum creatinine increased by 26% in patients without ototoxicity (P < 0.05, Mann-Whitney Rank sum test). Despite standardized hydration, discrete but significant changes of potassium, sodium, magnesium, and phosphate were observed during and/or after cisplatin infusion, which, however, did not discriminate between patients with and without ototoxicity.

CONCLUSIONS

While continuous cisplatin infusions are less nephrotoxic than repeated prolonged infusions, we observed considerable ototoxicity in patients treated with continuous cisplatin infusions, which necessitates further evaluations on the tolerance of continuous cisplatin infusions in children.

A phase II study with gemcitabine and split-dose cisplatin in patients with advanced non-small cell lung cancer

BACKGROUND

The combination of gemcitabine and cisplatin is among the most active regimens for the treatment of NSCLC. However, the optimal dose and schedule for administration of the two drugs has not yet been determined. We investigated the activity and toxicity of a gemcitabine and split-dose cisplatin regimen in an outpatient setting for patients with advanced non-small cell lung cancer (NSCLC).

PATIENTS AND METHODS

From June 2004 to May 2005 patients with stage IIIB or IV who had not had prior chemotherapy entered the study. Treatment consisted of gemcitabine 1250 mg/m2 and cisplatin 35 mg/m2, both given intravenously on days 1 and 8 every 21 days.

RESULTS

Forty-five patients were entered this study. Patient characteristics were as follows: male/female, 34/11; median age (range), 62 (30-76) years; ECOG PS 0/1/2, 7/30/8; stage IIIB/IV, 18/27. A total of 168 cycles were delivered, with a median of 4 cycles (range, 1-6). All patients were evaluable for toxicity. Grade 3 and 4 toxicities according to the NCI toxicity criteria included neutropenia in 8 patients (18%), anemia in 4 (9%), thrombocytopenia in 7 (15%), and emesis in 1 (2%). Of 42 patients assessable for response, 23 patients showed a partial remission. On intent-to-treat basis, the overall response rate was 51% (95% CI, 37-65%). Median time to progression was 6.0 months (range, 1.2-12.0 months) and median overall survival was 13.1 months (range, 1.4-17 months).

CONCLUSIONS

This regimen with gemcitabine and split-dose cisplatin using a 21-day schedule appears to be active and very well-tolerated in an outpatients setting for patients with advanced NSCLC.

Low urine osmolarity as a determinant of cisplatin-induced nephrotoxicity

Cisplatin is widely used in the treatment of human tumors, but it is a nephrotoxic drug. Early pragmatic clinical trials have shown that cisplatin-induced renal toxicity is greatly reduced through the use of high hydration, a large NaCl supply and mannitol infusion, but the precise mechanisms of these nephroprotective measures are not fully understood. We show here an increase in the cisplatin uptake and cytotoxicity on 56/10 A1 human glomerular and HK-2 human tubular cells when the drug incubation was performed in a hypotonic phosphate-buffered saline solution or in human urine ("drag in" transport hypothesis). When 4 mg/kg cisplatin was intraperitoneally injected in rats in 20 ml of a hypotonic 4 g/l NaCl solution, the platinum accumulation increased in both the cortex and papilla but not in the subcutaneously grafted colon tumors when compared to rats injected with cisplatin in normal or hyperosmotic solutions (9 and 14 g/l NaCl, respectively). The urea and creatinine blood levels were significantly increased, and more apoptotic cells were detected by the caspase-3 cleavage and TUNEL assays in the tubular cells of rats treated with cisplatin in a hypotonic solution compared to animals that received normal or hypertonic solutions. Osmolarity was sometimes low in urine from patients receiving an intravenous hydration for a cisplatin treatment or from healthy volunteers who were given an oral hydration with a 50 g/l glucose solution. Our results show that low urine osmolarity could be a major determinant in the increase of cisplatin-induced nephrotoxicity and justify the widely used concurrent infusion of osmotically active substances during intravenous hydration.

Retreatment with dose-dense weekly cisplatin after previous cisplatin chemotherapy is not complicated by significant neuro-toxicity

Cisplatin induces a cumulative dose-dependent axonal sensory neuropathy. With a cumulative dose over 600 mg/m2, a significant percentage of patients will develop a moderate or severe neuropathy. We retreated patients with progressive or recurrent ovarian cancer after previous platinum-containing chemotherapy with weekly 50-70 mg/m2 cisplatin for six cycles. This group was prospectively followed for the development of neuropathy. Patients received six weekly cycles of either 50 or 70 mg/m2 cisplatin, combined with oral etoposide. Responding patients continued treatment with daily oral etoposide for nine months. Neurological toxicity was assessed with a sensory sum score, the sensory neuropathy common toxicity criteria (CTC) and quantitated sensory analysis of the vibration perception threshold (VPT). Neurological assessment was scheduled at baseline, after three cycles, at the end of cisplatin chemotherapy and at 3 monthly intervals until 1 year after the discontinuation of chemotherapy. The first evaluation carried out in the interval of 1-4 months after the end of weekly cisplatin therapy was taken as the principle evaluation for neurotoxicity because during this time interval the nadir of cisplatin neurotoxicity is to be expected. Of 89 patients evaluated for neurological toxicity, 80 patients were fully evaluable. Forty-nine had received prior cisplatin (median cumulative dosage 450 mg/m2); the others had received prior treatment with carboplatin. Cisplatin pretreated patients had slightly higher neuropathy scores at the start of weekly cisplatin. Almost all cisplatin pretreated patients received six cycles of cisplatin, 29 at 50 mg/m2 and 20 at 70 mg/m2 per cycle. Despite treatment up to an overall cumulative dose of 750-900 mg/m2 cisplatin, only 1 patient discontinued treatment due to neurotoxicity. One other patient developed a grade 3 neuropathy during follow-up. Only a marginal increase of neuropathic signs and symptoms were observed in all the other patients. In multiple regression analysis, the increase in VPT or the sensory sum score was not related to prior treatment (cisplatin or carboplatin). Patients with mild signs of neuropathy after prior treatment with cisplatin to a cumulative dose level of 400-450 mg/m2 can be retreated with weekly cisplatin to a cumulative dose of 420 mg/m2 (overall cumulative dose up to 800-900 mg/m2) with only a minimal risk of significant neurotoxicity.

Induction chemotherapy employing dose-intense cisplatin with mitomycin and vinblastine (MVP400), followed by thoracic surgery or irradiation, for patients with stage III nonsmall cell lung carcinoma

BACKGROUND

Cisplatin-based induction chemotherapy before surgery or irradiation has improved the survival of patients with Stage III nonsmall cell lung carcinoma (NSCLC). Encouraged by earlier results with preoperative MVP (cisplatin [120 mg/m(2) or 25 mg/m(2)/week], vinblastine, and mitomycin) for Stage IIIA patients with clinically apparent mediastinal (N2) disease, the authors conducted a Phase II trial of the safety and efficacy of induction MVP400 with the dose intensity of cisplatin doubled from 25 to 50 mg/m(2) per week.

METHODS

From October 1992 to March 1996, 37 patients with Stage IIIA (26) or Stage IIIB (11) NSCLC began the MVP400 induction chemotherapy program. Four doses of cisplatin (100 mg/m(2)), 7 doses of vinblastine, and 2 doses of mitomycin were given over 9 weeks. Patients received either surgery or irradiation after induction treatment.

RESULTS

Overall, the response rate was 65% (95% confidence interval, 49-81%) with a complete resection rate of 67%. The median survival was 17 months, with 66% of patients alive at 1 year. Complete resection and Stage IIIA involvement were favorable prognostic indicators for survival. No Stage IIIB patients underwent a complete resection. Myelosuppression was the most common side effect. There were no treatment-related deaths.

CONCLUSIONS

Although high response and complete resection rates were again demonstrated, results with the MVP400 regimen were not improved over those achieved with MVP regimen tested earlier with Stage IIIA (N2) patients. The authors continue to recommend MVP as an induction chemotherapy regimen for clinical trials.

Comparative adverse effect profiles of platinum drugs

Since the discovery of the biologically active platinum complexes 30 years ago, 2 agents have become widely established in clinical oncology practice. Both cisplatin and carboplatin are platinum(II) complexes with 2 ammonia groups in the cis- position. However, they differ in their solubility, chemical reactivity, dichloride or alicyclic oxygenated leaving groups, pharmacokinetics and toxicology. Cisplatin causes severe renal tubular damage and reduces glomerular filtration, and requires concurrent saline hydration and mannitol diuresis to eliminate potentially lethal and unacceptable damage to the kidneys. Carboplatin, at conventional doses, causes no decrease in glomerular filtration and only minor transient elevations in urinary enzymes. Cisplatin is the most emetic cancer drug in common use, while nausea and vomiting associated with carboplatin are moderately severe. Serotonin release from enterochromaffin gut mucosal cells and stimulation of serotonin 5-HT3-receptors mediates acute emesis. Selective inhibitors of the 5-HT3-receptor protect against cisplatin- and carboplatin-induced nausea and vomiting. Peripheral neurotoxicity is the most dose-limiting problem associated with cisplatin. Loss of vibration sense, paraesthesia and sensory ataxia comes on after several treatment cycles. Carboplatin, however, is relatively free from peripheral neurotoxicity. Audiometry shows cisplatin-induced ototoxicity in 75 to 100% of patients, which may be associated with tinnitus and hearing loss. Ototoxicity is rare with conventional dose carboplatin therapy. Monitoring hearing with audiograms may identify early signs before significant impairment occurs. Cisplatin causes mild haematological toxicity to all 3 blood lineages. Haematological toxicity is dose-limiting for carboplatin, with thrombocytopenia being a greater problem than leucopenia. Although carboplatin is not toxic to the kidney, renal function markedly affects the severity of carboplatin-induced thrombocytopenia. The major clearance mechanism of cisplatin is irreversible binding in plasma and tissues, while carboplatin is cleared by glomerular filtration. Metabolism of cisplatin to aqua, amino acid and protein species is extensive, whereas carboplatin exists mainly as the free unchanged form. Strong relationships between carboplatin renal clearance, glomerular filtration rate, area under the plasma concentration-time curve (AUC) of filterable platinum and severity of thrombocytopenia have prompted dose adjustment according to renal function. New analogues such as JM216 offer the potential advantages of oral administration and few nonhaematological toxicities. Analogues based on the diaminocyclohexane ligand have encountered problematic neurotoxicity.

Neurotoxicity is not enhanced by increased dose intensities of cisplatin administration

It is uncertain whether intensive dosing schedules of cisplatin, intended to attain a higher anti-tumour efficacy, alter the severity of cisplatin-induced neuropathy. We assessed the development of neuropathy in three groups of patients treated with cisplatin in different dosing schedules. The severity of neuropathy was determined by measurement of the vibration perception threshold (VPT) before treatment and during follow-up for 2-12 months after the last cycle. 66 patients were treated with an intensive weekly regimen of doses varying from 70 to 85 mg/m2 in 1 day (trial A), 21 patients with a 3-weekly combination chemotherapy containing cisplatin 75 mg/m2 in 1 day (trial B) and 20 patients with a 3-weekly regimen containing cisplatin 20 mg/m2 for 5 consecutive days (trial C). The mean dose intensity achieved was 59 mg/m2/week in trial A, 21 mg/m2/week in trial B and 33 mg/m2/week in trial C. The maximum post-treatment VPT correlated significantly with pretreatment VPT (P < 0.001) and with the cumulative dose of cisplatin (P < 0.001). Following correction for these two variables, the maximum posttreatment VPT did not show a statistically significant association with dose intensity. These results suggest that neuropathy is not related to dose intensity of cisplatin. This implies that treatment with more intensive dosing schedules, employing equal cumulative doses of cisplatin, does not result in a concomitant increase in neurotoxicity within a cumulative dose range of 280-675 mg/m2.

Pharmacokinetic and biotransformation studies of ormaplatin in conjunction with a phase I clinical trial

Ormaplatin is a second-generation platinum (Pt) analogue with in vitro activity against some cisplatin-resistant malignant cell lines. We have evaluated the pharmacokinetics and biotransformations of ormaplatin during a phase I trial in which ormaplatin was administered by daily 30-min infusions on 5 consecutive days every 28 days. Sixteen patients received 25 courses at doses ranging from 5.0 to 11.6 mg/m2 per day. Pharmacokinetic parameters determined for ultrafilterable Pt measured by atomic absorption spectrophotometry revealed a short half-life (t1/2 16 min), moderate volume of distribution (Vd 12 l/m2), and relatively fast systemic clearance (Cls 544 ml/min per m2). Cls and percentage of drug unbound decreased during the 5-day administration period. Average systemic exposure increased with dose; however, inter-individual variability in Cls produced overlap in systemic exposure between the dose levels. The major active biotransformation product [PtCl2(dach)] was evaluated at the highest dose level by HPLC. This product decayed monoexponentially with a mean t1/2 of 13 min and a higher degree of pharmacokinetic variability than that of ultrafilterable Pt at this dose. No unreacted ormaplatin was detected; however, several inactive biotransformation products persisted for at least 120 min. Approximately 32% of the dose was excreted in the urine during the first day, one-third of this during the initial 1.5 h. The human pharmacokinetic characteristics of ormaplatin resemble those of cisplatin; however, additional study will be required to discern which analyte of ormaplatin correlates best with clinical effects.

High-dose cisplatin, etoposide, and cyclophosphamide with autologous stem cell reinfusion in patients with responsive metastatic or high-risk primary breast cancer

BACKGROUND

This study was designed to establish the feasibility of combining high-dose cisplatin, etoposide, and cyclophosphamide followed by stem cell rescue in patients with responsive metastatic or high-risk primary breast cancer.

METHODS

Eligibility criteria included the presence of high-risk primary breast cancer (Stage II with 10 or more involved axillary nodes or Stage IIIA or B) or Stage IV disease in complete or partial response; physiologic age 50 years or younger; Karnofsky performance status of 80% or greater; and creatinine clearance of 80 ml/minute or greater. Chemotherapy consisted of escalating doses of cisplatin (50-150 mg/m2 intravenously [IV]) given on days -12 and -5, etoposide (30 mg/kg IV) given on days -12 and -5, and cyclophosphamide (100 mg/kg IV) on day -3. On day 0, autologous bone marrow with or without peripheral stem cells, or granulocyte colony-stimulating factor primed peripheral stem cells alone were reinfused.

RESULTS

Thirty patients were enrolled in this study. Twenty-eight patients demonstrated no evidence of persistent renal damage after treatment. Two patients suffered symptomatic peripheral neuropathy, and one patient required a hearing aid 3 months after therapy. Hematopoietic toxicities were acceptable. There were two fatalities; Streptococcus viridans bacteremia and adult respiratory distress syndrome developed in one patient; and one patient who received 262 mg/m2 of cisplatin died of renal failure. Twelve of 18 assessable patients with Stage IV disease are without evidence of progression; 3 of these patients are progression-free at 11+, 12+, and 32+ months. With a median follow-up of 16+ months (range, 4-31 months), 7 patients of the group of 11 treated with high-risk primary breast cancer are without evidence of disease.

CONCLUSIONS

The Phase II dose of cisplatin when given on a day -12 and day -5 schedule in combination with etoposide and cyclophosphamide has been established at a total of 250 mg/m2. Dose-limiting toxicity has been defined as renal failure, and response rates were comparable to previously reported high-dose chemotherapeutic regimens.

Noninvasive follow-up of platinum pharmacokinetics in the skin of patients on cisplatin chemotherapy

BACKGROUND

Treatment with high-dose cisdiammine-dichloroplatinum (II) (cisplatin, cDDP) often is associated with late complications, predominated by peripheral neuropathy. Pt deposition in different tissues may play a key role in the induction of many of these effects. Main topics of interest include the relationship between cDDP doses given during treatment and the long-term pharmacokinetics of the drug complexes in normal tissues and blood. Noninvasive examination of Pt in tissues during and after cDDP treatment are needed to clarify these points.

METHODS

A novel, high-sensitivity diagnostic x-ray spectrometry (DXS) method was used for the fast, noninvasive analysis of Pt in external tissues of patients with cancer treated with courses of cDDP. The Pt in a small skin area was excited by a monochromatic soft x-ray beam (14.6 KeV) and the spectral L lines emitted from the tissue were detected. A limit of detection below 1 microgram/g wet weight was reached. The pharmacokinetics of Pt in blood was investigated in parallel with the use of high-sensitivity, flameless atomic absorption spectrometry (AAS).

RESULTS

Follow-up of Pt concentrations in the skin of patients with cancer by DXS before cDDP treatment, during treatment, and up to 4 months after its completion, showed prolonged Pt deposition that corresponded to the net cumulative doses of the drug. Pt clearance from the skin fitted a monoexponential curve with a half-life of about 30 days. In comparison, the pharmacokinetics of total Pt in plasma showed a much faster, biexponential clearance with half-lives of 41 minutes and 5.2 days, respectively.

CONCLUSIONS

The amount of nonspecific Pt deposition in the tissues was found to depend on the total doses administered, the time interval between the courses, and the slow rate of clearance. Noninvasive measurements of tissue Pt levels may serve as a major tool in the evaluation of the induction of late cDDP complications.

Renal dysfunction during high-dose cisplatin therapy and autologous hematopoietic stem cell transplantation: effect of aminoglycoside therapy

PURPOSE

Renal dysfunction is a common cause of morbidity after cancer therapy and bone marrow transplantation. In this study, we evaluated the effects of aminoglycosides and other nephrotoxic antibiotics on the occurrence of renal dysfunction in patients who received high-dose cisplatin-containing chemotherapy regimens.

PATIENTS AND METHODS

The subjects of this analysis were 102 consecutive patients, studied from September 1985 to February 1991, who received high-dose cisplatin, administered as 40 mg/m2 for 5 consecutive days in 3% saline with saline hydration and mannitol diuresis, followed by autologous stem cell transplantation. Renal dysfunction was defined as an increase in serum creatinine greater than or equal to 44.2 mumol/L above baseline.

RESULTS

Characteristics of the 43 patients who were given aminoglycosides were similar to those in patients who did not receive aminoglycosides with respect to initial renal function, age, cancer type, and previous exposure to cisplatin. Patients who experienced serious treatment-related toxicities such as hemorrhage or septicemia were more likely to have received aminoglycoside antibiotics (p = 0.005). A multivariate analysis showed that increased duration of neutropenia, advanced patient age, and amphotericin B use were predictors of renal failure. Aminoglycoside therapy did not significantly increase the risk of renal dysfunction.

CONCLUSIONS

Our data suggest that with appropriate supportive care measures, aminoglycosides can safely be administered to febrile, neutropenic patients who recently have received high-dose cisplatin therapy.

WR2721 as a modulator of cisplatin- and carboplatin-induced side effects in comparison with other chemoprotective agents: a molecular approach

Cisplatin is an active cytostatic that became successful in the treatment of several types of solid tumours after its nephrotoxic potential was controlled by hydration and diuresis. Thiol compounds were tested to reduce further cisplatin-induced nephrotoxicity. Thiosulphate is rapidly excreted by the kidneys and protects against cisplatin-induced nephrotoxicity by inactivating reactive platinum species in the kidney. Due to inactivation of cisplatin in the circulation, thiosulphate also interferes with its antitumour activity. Therefore, it is mainly used in two-route schedules, whereby cisplatin is delivered locally to the tumour (i.p. or i.a.) while systemic (i.v.) thiosulphate protects the kidneys. Diethyldithiocarbamate was shown to protect against cisplatin-induced nephrotoxicity in several animal models by reversing cellular damage. However, in the clinic it has been less successful, partly due to its central nervous system toxicity. The endogenous thiol compounds glutathione and metallothionein have been shown to reduce cisplatin-induced toxicity both in animal models and in clinical trials. However, the results are rather preliminary and a reduction in therapeutic efficacy may be expected, for both glutathione and metallothionein have been reported to be involved in platinum resistance. The thioether methionine has been shown to reduce cisplatin-induced nephrotoxicity in animal models but it has not yet been tested in the clinic. Cisplatin-induced acute emesis can be sufficiently controlled with a new class of 5-hydroxytryptamine-3 (5HT3)-receptor blockers, but delayed emesis remains a problem. High-dose cisplatin regimens with protection of the kidneys induces ototoxicity, peripheral neuropathy and myelotoxicity, which become dose-limiting. Neurotoxicity was partly reversed by the neurogenerative agent ORG2766, but this agent does not reduce other cisplatin-induced toxicities. Therefore, an agent capable of protecting multiple non-tumour tissues is needed. Carboplatin is a second-generation analogue of cisplatin with less nephro-, neuro- and ototoxicity. Carboplatin is at least as active as cisplatin at its maximum tolerated dose, which is defined by its myelotoxicity. Protection from carboplatin-induced myelotoxicity may be controlled by autologous bone marrow transplantation and/or hematopoietic growth factor infusions. High-dose carboplatin schedules may cause nephrotoxicity, neurotoxicity and ototoxicity. Again, the protection of multiple non-tumour tissues is needed. WR2721 appears to be such a modulating agent capable of protecting multiple non-tumour tissues. It was shown to be preferentially metabolized and taken up as the thiol metabolite WR1065 by non-tumour tissues as compared with (hypoxic) solid tumours. It was shown to protect mice from cisplatin-induced nephrotoxicity and from cisplatin- and carboplatin-induced myelotoxicity without interfering with the antitumour activity.(ABSTRACT TRUNCATED AT 400 WORDS)

Renal salt wasting in patients treated with high-dose cisplatin, etoposide, and mitomycin in patients with advanced non-small cell lung cancer

Cisplatin has many toxic effects; emesis, impairment of renal function, myelosuppression, peripheral neuropathy, ototoxicity and renal tubular wasting. We used MVP regimen (Mitomycin C, Vp-16, and Cisplatin) in advanced Non-Small Cell Lung Cancer (NSCLC). Using hydration and prophylactic supplementation of sodium and potassium before and during chemotherapy, we have observed the development of hyponatremia in 48 courses (43%), hypokalemia in 23 courses and hypomagnesemia in 11 courses. Some patients showed abnormalities of renal function in 16 courses. All the electrolyte depletion and renal problem was corrected before next courses by hydration and replacement of the wasting. Frequent measurement of serum cation and appropriate replacement are recommended when high dose Cisplatin containing regimen is used in chemotherapy of neoplasms.

Pilot study of a rapid etoposide-cisplatin regimen in paediatric soft tissue sarcomas

10 patients with refractory or relapsed soft tissue sarcoma were treated with weekly etoposide (150 mg/m2 on days 1, 2 and 3) and cisplatin (60 mg/m2 on day 2). Toxicity was mainly myelosuppression which resulted in deviation from planned weekly chemotherapy scheduling. With this rapid dose-delivery schedule the tolerated median dose intensities were 161 mg/m2 per week for etoposide and 49 mg/m2 per week for cisplatin. In 9 evaluable patients there were 7 responses, 2 complete and 5 partial, giving a response rate of 78% (confidence interval 51-100%). The combination of etoposide and cisplatin in this schedule produced a higher response rate than reported with previous schedules and is worthy of further evaluation.

Selecting dose-intense drug combinations: metastatic breast cancer

A mathematical model previously described is applied to the problem of selecting drug combinations for metastatic breast cancer. The model accounts for the differing single-agent activities of the drugs as well as their differing profiles of toxicity. With no bone marrow protection, combinations with cisplatin offer a small improvement in total equivalent dose over therapy with the more active single-agents. Restricting consideration to the four most commonly used agents, single-agent doxorubicin has the greatest equivalent dose. With protection for leukopenia or willingness to accept a higher incidence of severe leukopenia, a combination with large doses of cyclophosphamide, doxorubicin, and fluorouracil, and a small dose of cisplatin has greatest equivalent dose. The doublets cyclophosphamide/fluorouracil or fluorouracil/cisplatin at higher doses are almost as good. With protection for leukopenia and thrombocytopenia, a cyclophosphamide/thiotepa combination at very high doses maximizes total equivalent dose. This approach can be used to identify regimens worthy of prospective evaluation.

Cisplatin and novobiocin in the treatment of non-small cell lung cancer. A Southwest Oncology Group study

Novobiocin, a commercially available oral antibiotic, inhibits DNA topoisomerase II in a manner shown in cell culture to enhance the cytotoxicity of alkylating agents and cisplatin. Thirty-six patients were entered on a Phase II trial using high-dose cisplatin (100 mg/m2 on days 1 and 8 for four cycles) after steady-state dosing with novobiocin (1000 mg or four 250-mg capsules every 12 hours for six doses, four of which were administered before each dose of cisplatin). One patient remains on study and cannot be evaluated for response. No complete responses were seen. Three patients (8%) had partial responses and an additional patient had an unconfirmed partial response. The median survival time of all patients was just less than 7 months. These results are comparable with those of other concurrent Southwest Oncology Group (SWOG) Phase II and III trials of high-dose cisplatin in non-small cell lung cancer (NSCLC). Novobiocin plasma levels were obtained for three patients and were approximately 50% of the optimal concentration as reported in cell culture for potentiation of cytotoxicity. It was concluded that an optimum test of novobiocin as a modulator of cytotoxicity may require the availability of an intravenous preparation.

Rapidly alternating radiotherapy and high dose cisplatin chemotherapy in stage IIIB non-small cell lung cancer: results of a phase I/II study

Alternating radiotherapy and chemotherapy increases tumor cure rates in some animal models with reduced normal tissue damage compared to sequential use of these modalities. To test this concept in non-small cell lung cancer, 23 patients with predominantly Stage IIIB disease were treated on a Northern California Oncology Group pilot study of alternating radiotherapy and high dose cisplatin. Radiotherapy consisted of 6000 cGy delivered in three separate 10-day courses of 200 cGy/fraction/day during weeks 1 and 2, 5 and 6, and 9 and 10. High dose cisplatin, 100 mg/m2 in 3% saline, was administered on weeks 3 and 4, 7 and 8, 11 and 12, and 15 and 16. The response rate in 22 eligible patients is 73% (16/22) with four complete responses and 12 partial responses. Feasibility of this approach is demonstrated by 20/22 patients completing radiotherapy and a median of 2.5 courses of chemotherapy administered. Median survival time is 14.2 months (range 2-40+ months). One- and 2-year survival rates are 64% (14/22) and 41% (9/22), respectively. Hematologic, renal, and radiation-related toxicities were significant but manageable. We conclude that rapid alternation of radiotherapy and a high dose intensity cisplatin regimen is feasible in Stage IIIB non-small cell lung cancer, with a high response rate and acceptable toxicity. The long-term impact on local control and survival remains unclear, although preliminary survival data are encouraging in this poor prognosis population. Further studies of this concept are warranted.

The use of probenecid as a chemoprotector against cisplatin nephrotoxicity

Probenecid inhibits cisplatin (CP) secretion in humans and protects against CP-induced nephrotoxicity in rats. The authors conducted a Phase I trial of escalating doses of CP using probenecid as a chemoprotector. Fifty-four courses of CP at doses ranging from 100 to 160 mg/m2 were given by 24-hour infusion to 36 patients. There was no renal impairment at any dose. Ototoxicity, however, became the dose-limiting toxicity; 14 patients experienced a 20 or greater decibel (dB) loss. Seven percent of courses were associated with a leukocyte count of less than 1.5 x 10/microliters, and 19% with a platelet count of less than 50 x 10(3)/microliters. Only three patients developed neurotoxicity. Correlating pharmacokinetic data and toxicity, the authors found that high cumulative dose, area under the curve (AUC) for unbound platinum, and cumulative AUC were associated with ototoxicity and peripheral neuropathy. It was concluded that probenecid may protect against CP nephrotoxicity and warrants further investigation. Its unique mechanism of action and lack of toxicity make it ideal to combine with other chemoprotectors.

Phase-1 trial of high-dose intravenous cisplatin with simultaneous intravenous sodium thiosulfate

Previous pharmacological and clinical data have suggested that it is possible to increase significantly the dose of "active" cisplatin delivered systemically by the simultaneous administration of intravenous sodium thiosulfate. In order to define more critically the toxicity and potential efficacy of this therapeutic approach, 36 patients with a variety of solid tumors and limited pretreatment were entered into a phase-1 trial of high-dose intravenous cisplatin plus sodium thiosulfate. The maximally tolerated dose of cisplatin was found to be 200 mg/m2, excessive renal toxicity being observed at a dose of 225 mg/m2 (6/14 courses associated with serum creatinine rise to greater than 2.0 mg-%). Following several courses of high-dose cisplatin, peripheral neuropathy becomes the limiting toxicity (9/15 patients receiving at least three courses of cisplatin at greater than or equal to 150 mg/m2 experienced at least grade-1 neuropathy). Significant ototoxicity developed after only one or two treatment courses, but with continued treatment hearing loss appeared to stabilize in the moderately severe range in most patients. Major responses (PR/CR) were observed in 7/27 evaluable patients. We conclude that cisplatin can be administered at a dose at 200 mg/m2 as a 2-h infusion (with simultaneous sodium thiosulfate) with significant but acceptable toxicities and without evidence of loss of anti-neoplastic activity (secondary to the presence of thiosulfate). However, owing to the development of neurotoxicity most patients will be unable to receive more than three courses of this high-dose treatment regimen.

Treatment of non-small-cell lung cancer with vinblastine and very high-dose cisplatin. A Southwest Oncology Group study

Suggestions of a dose-response effect for cisplatin in non-small-cell lung cancer have contributed to the development of very high-dose cisplatin regimens (200 mg/m2 per cycle). We treated 53 eligible patients with metastatic or recurrent non-small-cell lung cancer with a combination of 100 mg/m2 cisplatin and 4 mg/m2 vinblastine, each given on days 1 and 8 of a 28-day cycle. We observed no complete response and 4 partial responses (8%). Median survival was 6 months. Toxicities of grade III or greater included leukopenia (11 cases), nausea/vomiting (6 cases), thrombocytopenia (2 cases), anemia (2 cases), and elevation of transaminase (1 case). Neurotoxicity has been reported to be a major problem in several other very high-dose cisplatin regimens. The low level of neurotoxicity observed in this study may be attributable to the median cumulative cisplatin dose of less than 600 mg/m2. This vinblastine/very high-dose cisplatin regimen showed minor activity against non-small-cell lung cancer. The level of activity did not surpass that of standard-dose (100 mg/m2 per cycle) cisplatin-containing regimens.

A randomized study of two vindesine plus cisplatin-containing regimens with the addition of mitomycin C or ifosfamide in patients with advanced non-small cell lung cancer

The current trial was carried out to assess the survival enhancement achieved, if any, by adding ifosfamide to vindesine and cisplatin (IVP) in contrast to mitomycin plus vindesine and cisplatin (MVP). Between June 1986 and September 1988, 110 patients were randomly allocated to receive either ifosfamide (3 g/m2 plus 3 g/m2 of mesna) or mitomycin 8 mg/m2, on days 1, 29, and 71 only. In both arms vindesine was given 3 mg/m2 weekly X 5 then every 2 weeks. In the MVP arm, 120 mg/m2 of cisplatin was administered on days 1 and 29 and then every 6 weeks, whereas in the IVP arm 100 mg/m2 of cisplatin was given on the same time schedule. One hundred three patients were evaluable for response and toxicity and 56% of patients had Mountain's Stage IV disease. The response rate was 26% (14/53 patients) in the MVP arm (95% confidence interval, 14%-39%) and 20% (ten of 50 patients) in the IVP arm (95% confidence interval, 10%-34%). Neither the response rate nor the median survival times were significantly different, although more nephrotoxicity was produced in the MVP arm, grade 1+ in 43% versus 26% in IVP arm (P = 0.04). Results obtained from this study fail to demonstrate that mitomycin or ifosfamide have a synergistic effect on the efficacy of the vindesine/cisplatin combination.

Phase I study of oxaliplatin in patients with advanced cancer

Oxaliplatin, or trans-1-diaminocyclohexane-platinum, was tested in a phase I study. A total of 44 patients received 116 courses with dose escalation from 45 to 200 mg/m2. Neither renal nor hematologic toxicities were observed at doses up to 200 mg/m2. Gastrointestinal toxicity was practically constant and often of grade 3-4 on the WHO scale (53% of patients). The dose-limiting toxicity was a peculiar sensory neuropathy; the first neurologic phenomena appeared at a dose of 135 mg/m2 and continued thereafter, occurring after 75% of the courses with mild to moderate intensity (WHO grade 1-2 after 67% of the courses). Neurotoxicity was cumulative and six patients developed grade 3 disabling neuropathy after a cumulative dose of 500 mg/m2, with walking and handwriting difficulties being slowly regressive in three cases. A peculiar symptom was the influence of temperature, with exacerbation of parethesias when patients touched cold surfaces. Nerve-conduction studies carried out in six cases showed a predominantly sensory neuropathy with axonal degeneration. No other toxicities were observed, although audiograms were not systematically done. We observed four partial responses that lasted 6-13 months in patients with oesophageal (2 cases), lung (1), and urothelial cancer (1); two of these patients had been pretreated with cisplatin. Since neurologic side effects occur very frequently and may produce a long-lasting sensory neuropathy, for phase II studies we recommend a starting dose of 135 mg/m2, with a careful neurologic survey.

High-dose cisplatin and mitomycin C in advanced non-small cell lung cancer: a phase II study of the Northern California Oncology Group

To investigate chemotherapeutic dose intensity in advanced non-small-cell lung cancer (NSCLC), we evaluated a pharmacokinetically designed schedule of high-dose cisplatin (200 mg/m2 per 28-day cycle) plus mitomycin C. Between March 1987 and March 1989, 62 patients were registered for a phase II study of the Northern California Oncology Group (NCOG). The treatment schedule consisted of cisplatin in hypertonic saline given on a divided days 1 and 8 schedule (100 mg/m2 on each day) plus mitomycin C given at a dose of 8 mg/m2 on day 1 of each cycle. In 61 patients evaluable for response analysis, the overall response rate was 39% (24/61), with a complete response being achieved in 6% (4/61) of cases and a partial response, in 33% (20/61). The response according to reviewed histologic subtype included squamous, 53% of patients (10/19); large cell, 31% (4/13); and adenocarcinoma, 34% (10/29). The median survival for all patients was 29.3 weeks. The mean cisplatin and mitomycin C delivered dose intensities in this study were 45 mg/m2 per week (90% of the projected dose) and 1.5 mg/m2 per week (75%). The toxicity of this combination regimen in the 62 enrolled patients was significant but manageable. Leukopenia (WBC, less than 1,000/mm3) and thrombocytopenia (platelets, less than 25,000/mm3) occurred in 3% and 8% of patients treated, respectively. Dose-limiting renal toxicity and clinically significant ototoxicity developed in 8 patients each (13%), and a peripheral sensory neuropathy was observed in 17 cases (27%). Whether this type of dose-intensive therapy results in an improved therapeutic index in NSCLC is currently being evaluated in a randomized comparative trial versus standard-dose cisplatin therapy.

Cisplatin rescue therapy: experience with sodium thiosulfate, WR2721, and diethyldithiocarbamate

Cisplatin has a steep dose response curve for both antitumor and adverse effects. Therapeutic strategies aimed at reducing toxicity and allowing dose escalation of intravenous cisplatin, such as administration in hypertonic saline and pharmacokinetically based dosing schedules, have been partially successful in reducing nephrotoxicity and bone marrow suppression. However, new dose-limiting toxicities consisting of peripheral neuropathy and ototoxicity have emerged, which continue to restrict potential use of high dose cisplatin therapy. Intraperitoneal administration of high dose cisplatin also offers the potential of markedly increased local drug exposure if systemic toxicity can be avoided. Proposed chemoprotective agents, including sodium thiosulfate, WR2721, and diethyldithiocarbamate (DDTC) are being extensively examined as "rescue agents" for either regional or systemic administration of cisplatin. Although each agent offers unique advantages to be considered in developing successful rescue therapy, many questions remain regarding molecular and pharmacokinetic interactions with cisplatin, appropriate dosing schedules, and effects on antineoplastic activity. We present a review of current investigations of chemoprotectors for prevention of cisplatin-related toxicities.

High-dose cisplatin in disseminated melanoma: a comparison of two schedules

A total of 38 patients with metastatic melanoma received monthly chemotherapy with cisplatin at a dose of 200 mg/m2, per cycle; 14 received 20 mg/m2 cisplatin i.v. on days 1-5 and 24 were given 100 mg/m2 i.v. on days 1 and 8. Objective responses were seen in 2/14 treated on days 1-5 and in 5 of 22 evaluable subjects receiving cisplatin on days 1 and 8, for an overall response rate of 22%. The median survival of all patients was 6 months, with no significant difference observed between the two schedules. Severe neurotoxicity and myelosuppression were more common in patients treated on days 1-5. Two patients treated in this manner were bedridden due to neurotoxicity and four developed grade 4 leukopenia after the first cycle of chemotherapy. Only one patient treated with the divided-dose schedule became leukopenic during the first cycle, and none of the patients were debilitated by neurotoxicity. Thrombocytopenia was statistically more severe. Nausea and vomiting, fatigue, ototoxicity, and paresthesia were seen with equal frequency. Very high doses of cisplatin can be delivered with acceptable toxicity using a divided-dose schedule. As the response rate on this schedule appeared to be comparable with that achieved on the more toxic consecutive 5-day schedule, the former deserves to be tested in diseases known to show a dose response to cisplatin. However, in melanoma, administration of 200 mg/m2 per course did not appear to be associated with a markedly improved response rate, compared with cisplatin alone at "standard" doses.

Pharmacokinetics of cisplatin in patients receiving interleukin-2-containing treatment regimens

Plasma cisplatin pharmacokinetics were determined in 6 patients enrolled in a phase I trial of combined high-dose cisplatin and Interleukin-2 (IL-2) therapy. Cisplatin (100 mg/m2) was given in 3% saline as a 3-h infusion on days 1 and 8 of each 28-day cycle; IL-2(2-4 x 10(6) units/m2) was given as an i.v. bolus on days 15-19 in a dose escalation trial. Peak total and ultrafiltrate plasma platinum concentrations were 1.15 and 0.172 micrograms/ml for cycle 1 and 1.2 and 0.124 micrograms/ml for cycle 3, respectively. The AUCs for total and ultrafiltrate plasma platinum were 7.33 and 0.965 micrograms/ml per hour for cycle 1 and 8.48 and 0.924 micrograms/ml per hour for cycle 3, respectively. Total body clearances for total and ultrafiltrate platinum were 0.051 and 0.525 ml/h for cycle 1 and 0.042 and 0.443 ml/h for cycle 3, respectively. These data demonstrate no significant effects of IL-2 on the plasma pharmacokinetics of cisplatin in the dose schedule given and support the feasibility of this combined modality therapy.

High-dose cisplatin with diethyldithiocarbamate (DDTC) rescue therapy: preliminary pharmacologic observations

Diethyldithiocarbamate (DDTC), a chelating agent that is a major metabolite of disulfuram, has been proposed as a potential rescue agent to reduce toxicity following high-dose cisplatin (HDCP) therapy. In the present study, we examined the pharmacologic interaction of HDCP and DDTC given as rescue therapy. Total plasma platinum and ultrafiltrate platinum pharmacokinetics and DDTC levels were determined in six patients with advanced malignancies who received a total of 11 cycles of HDCP with DDTC rescue. HDCP therapy (200 mg/m2 per cycle) consisted of 100 mg/m2 reconstituted in 250 cc 3% saline and infused over 3 h on days 1 and 8 of each 28-day cycle. DDTC rescue at a dose of 4 gm/m2 was given by an i.v. infusion (duration 1.5-3.5 h), beginning 45 min after the completion of cisplatin infusion. Peak total and ultrafiltrate levels and cisplatin pharmacokinetics in this study were indistinguishable from those of previous studies using the same HDCP regimen without DDTC rescue. Ultrafiltrate or unbound plasma platinum was less than 10% of total plasma platinum concentrations and demonstrated a biphasic pattern of elimination. Levels of DDTC predicted to be chemoprotective (greater than 400 microM) were achieved with the dose and schedule used in this study. These data demonstrate that DDTC can be targeted to protective plasma concentrations without significantly altering plasma cisplatin pharmacokinetics and support the potential usefulness of DDTC as a rescue agent following HDCP therapy.

Progressive paresthesias after cessation of therapy with very high-dose cisplatin

Control of cisplatin-induced nephrotoxicity and nausea/vomiting has enabled the development of very high-dose cisplatin regimens (monthly total dose, 200 mg/m2). Neurotoxicity is now recognized to be the dose-limiting toxicity of these regimens. However, during a pilot study involving 5 mg/m2 vinblastine and 100 mg/m2 cisplatin given every 28 days on days 1 and 8 for the treatment of advanced non-small-cell lung cancer, we noted a high incidence of progressive peripheral neuropathy, which continued for several months after the discontinuation of cisplatin chemotherapy. Of the six patients treated, four received at least three cycles of therapy (median total cisplatin dose, 685 mg/m2; range, 500-725 mg/m2). All four patients developed a progressive peripheral neuropathy, with a worsening of toxicity by 1-3 grades over the 2-3 months after cisplatin discontinuation. One patient progressed from grade I (mild paresthesia) to grade IV (inability to ambulate) over a period of 3 months after the discontinuation of therapy. Stricter rules for early dose de-escalation and discontinuation may be required for very high-dose cisplatin regimens. Delayed progressive neuropathy should be recognized as a possible late complication of this form of therapy.

Biochemical modulation of cisplatin toxicity

The biochemical modulation of cisplatin toxicity has contributed substantially to the safe and effective administration of cisplatin in the clinic. In most cases, however, the demonstration of clinical efficacy has preceded the understanding of mechanisms by which these agents provide protection to normal tissues. A number of protocols are now available to ameliorate cisplatin-induced nephrotoxicity; these approaches have been so successful that renal toxicity is rarely of clinical significance today. However, the dramatic escalation in cisplatin dose engendered by the use of modulators has resulted in new dose-limiting toxicities involving the nervous system and the bone marrow. Although preliminary data suggests that certain modulators may reduce these toxicities, extensive clinical trials will be necessary to substantiate the beneficial effects in the clinic. Further clinical studies will also be necessary to determine the optimum scheduling for the newer agents and to provide convincing evidence of efficacy in man. Finally, modulator combinations (i.e. DDTC and hypertonic saline) have the potential to provide the broadest coverage of normal tissue protection and appear to merit more extensive clinical investigation. Cisplatin has demonstrated remarkable clinical efficacy at currently tolerated doses; further advances in the biochemical modulation of cisplatin toxicity should provide significant therapeutic gains for this important drug in the future.