Results of plasma N-terminal pro B-type natriuretic peptide and cardiac troponin monitoring in GIST patients do not support the existence of imatinib-induced cardiotoxicity

Background: Recently, case reports of patients treated withimatinib (imatinib mesylate; Gleevec®; Glivec®) indicatedthat this tyrosine kinase inhibitor may induce cardiomyopathy.Consequently, careful cardiac monitoring was advocated for clinicalstudies. The purpose of this study was to prospectively evaluatewhether imatinib (Gleevec) induces early, subclinical, cardiactoxicity. Patients and methods: History and physical examination werecarried out with special attention for symptoms of heart failure.Additionally, assessments of serial plasma N-terminal pro B-typenatriuretic peptide (NT-proBNP) and serum cardiac troponin T(cTnT) measurement before and 1 and 3 months after the startof imatinib treatment (400–800 mg daily) were done inpatients with advanced and/or metastatic gastrointestinal stromaltumours (GIST). Results: A total of 55 GIST patients were enrolled. Only onepatient, with a normal pretreatment NT-proBNP, showed an increasein NT-proBNP to above age-specific normal values during imatinibtreatment and developed symptomatic heart failure due to pre-existentcardiac valvular disease. cTnT levels remained stable. Conclusions: In our study population, imatinib treatment forGIST was not associated with an increase in plasma NT-proBNPlevels, indicating that the risk of subclinical cardiac toxicityis limited with the use of this agent. These results do notsupport the current strategy to standard cardiac monitoringin all patients. This may be restricted to GIST patients witha history of cardiac disease. Key words: cardiotoxicity, GIST, imatinib mesylate, NT-proBNP, troponin T Received for publication August 15, 2007. Revision received August 24, 2007. Accepted for publication August 29, 2007.     

Gemcitabine in patients with advanced malignant melanoma or gastric cancer: Phase II studies of the EORTC Early Clinical Trials Group

BACKGROUND:: Gemcitabine is a water-soluble analogue of deoxycytidine whichhas shown significant antitumour activity in a broal panel ofslow-growing murine and human carcinomas. Objective responseshave been reported in early clinical studies in breast, headand neck, non-small cell lung cancer patients. The weekly schedulewas selected for disease-oriented phase II studies because ofits better tolerabil-ity as compared to daily or twice-weeklyschemes. PATIENTS AND METHODS:: Gemcitabine (1000 mg/m²) was given as a 30. min. infusion, weeklyfor three consecutive weeks, followed by one-week rest, every4 weeks. Twenty-nine patients with locally advanced/metastaticgastric cancer and 39 patients with metastatic malignant melanomaentered the study. No prior chemotherapy for advanced diseasehad been given in all cases. RESULTS:: Among 26 evaluable patients with gastric cancer, 1 partial response(PR) of 9 months (4%), 11 no change (NC) and 14 tumour progression(PD) were observed. Of 33 evaluable patients with malignantmelanoma, 1 patient achieved a PR for 10 months (3%), 2 hadNC and 30 PD. Toxicity was similar in the two groups with moderatemyelosuppression, mainly neutropenia, mild to moderate nauseaand vomiting in 70% of patients and fatigue grade 1–2in 50%. CONCLUSIONS:: At the tested schedule gemcitabine has no relevant antitumouractivity in previously untreated patients with advanced malignantmelanoma or gastric cancer. gemcitabine, phase II study, advanced gastric cancer, melanoma     

Docetaxel (Taxotere) in advanced gastric cancer: results of a phase II clinical trial. EORTC Early Clinical Trials Group.

Thirty-seven eligible patients, median age 59 years (range 37-72) and median performance status 1 (0-2), with advanced, untreated, measurable gastric carcinoma were given docetaxel, 100 mg m-2 i.v. over 60 min without premedication, once every 3 weeks. Metastatic sites included the liver in 12 patients and retroperitoneal lymph nodes in 16. Eight of the 33 evaluable patients (24%) achieved a partial remission for a median of 7.5 months (3-11+). An additional 11 patients had stabilisation of disease. The patients received a median of four cycles of docetaxel (range 1-8) for a total of 156 courses. Dose reduction was necessary in 30 cycles; 14 cycles were delayed a mean of 3 days. Haematological toxicity consisted mainly of non-cumulative neutropenia, with a median nadir count of 0.35 x 10(9) l-1 (0.04-1.64) and eight episodes (5%) of leucopenic fever; non-haematological toxicities included alopecia, mild nausea and vomiting and allergic manifestations such as skin rash and pruritus. There were no drug-related deaths. Our data indicate that docetaxel is an active agent in advanced gastric cancer; further clinical investigations seem warranted.     

Relationship between the exposure to cisplatin, DNA-adduct formation in leucocytes and tumour response in patients with solid tumours.

The study was designed to investigate possible relationships between tumour response and exposure to cisplatin (area under the curve of unbound cisplatin in plasma, AUC) and DNA-adduct formation in leucocytes (WBC) in patients with solid tumours. Patients were treated with six weekly courses of cisplatin at a dose of 70 or 80 mg m-2. The AUC was determined during the first course and DNA-adduct levels in WBC during all courses at baseline, 1 h (A(max)) and 15 h after a 3 h infusion of cisplatin. The area under the DNA-adduct-time curve (AUA) was calculated. The tumour response was determined after six courses. Forty-five evaluable patients received 237 courses of cisplatin. Sixteen patients with head and neck cancer received a dose of 80 mg m-2 and 29 with various other tumour types received 70 mg m-2 plus daily 50 mg oral etoposide. There were 20 responders (partial and complete) and 25 non-responders (stable and progressive disease). The AUC was highly variable (mean +/- s.d. = 2.48 +/- 0.51 micrograms h-1 ml-1; range 1.10-3.82) and was closely correlated with the AUA (r = 0.78, P < 0.0001) and A(max) (r = 0.73, P < 0.0001). The AUC, AUA and A(max) were significantly higher in responders than in non-responders in the total population (P < 0.0001) and in the two subgroups treated at 70 or 80 mg m-2. In logistic regression analysis AUC, AUA and A(max) were important predictors of response. The magnitude of exposure to cisplatin is, through DNA-adduct formation, the major determinant of the response rate in this population. Hence, individualised dosing of cisplatin using AUC or DNA-adducts should lead to increased response rates.     

Docetaxel and paclitaxel inhibit DNA-adduct formation and intracellular accumulation of cisplatin in human leukocytes

 The purpose of this study was to determine the mechanism of the pharmacodynamic interaction between docetaxel/paclitaxel and cisplatin. Cisplatin-induced DNA-adducts and cisplatin accumulation were quantitated in peripheral blood leukocytes (WBC). The WBC were obtained from patients treated with docetaxel or paclitaxel in phase I/II studies and were incubated in vitro with cisplatin. In addition, blank whole-blood samples were obtained from patients and healthy subjects and incubated in vitro with cisplatin or docetaxel/paclitaxel and cisplatin. The cisplatin-induced DNA-adduct levels measured in WBC after treatment with docetaxel or paclitaxel were significantly lower than those determined in non-pretreated WBC. Docetaxel and paclitaxel reduced the intracellular accumulation of cisplatin in WBC by 46–47%. If the pharmacodynamic interaction between docetaxel/paclitaxel and cisplatin also occurs in other normal tissues such as bone marrow, it may well contribute to the sequence dependent toxicity that has been observed in clinical studies. Received: 15 February 1995/Accepted: 6 June 1995     

Effects of impaired renal function on the pharmacokinetics and toxicity of i.v. ZD9331, a novel non-polyglutamated thymidylate synthase inhibitor,in adult patients with solid tumors

ZD9331 is a potent thymidylate synthase inhibitor. Renal and hepatic clearances were found to be important routes of elimination. The objectives of this pharmacologic trial were to investigate the effect of renal impairment on the pharmacokinetics of ZD9331, to study the toxicity profile and to document any antitumor effects of ZD9331 when administered i.v. to patients with different degrees of renal impairment. Patients were treated with ZD9331 130 mg/m2 given as an i.v. infusion on day 1 of a 4-week cycle to allow full pharmacokinetic assessment. Subsequent cycles involved the administration of ZD9331 on days 1 and 8, every 3 weeks. Patients were stratified according to their renal function assessed by the creatinine clearance: normal renal function (creatinine clearance > or =60 ml/min), mildly impaired renal function (creatinine clearance > or =40 to <60 ml/min) and moderately impaired renal function (creatinine clearance >25 to <40 ml/min). For pharmacokinetic analysis plasma sampling was performed during the first course and assayed using a validated liquid chromatographic tandem mass spectrometry assay. Twenty-three patients were entered on the study, of whom 21 received 130 mg/m2 ZD9331 in the first treatment cycle. No relationship was seen between renal impairment and plasma clearance nor with the area under the concentration-time curve of free ZD9331. Increasing renal impairment was associated with a greater incidence of myelosuppression. No predictive relationship between the clearance of free ZD9331 and the degree of renal impairment as determined by creatinine clearance could be assessed. However, data from this trial indicate that increased renal impairment may be associated with greater ZD9331-induced toxicity, particularly myelosuppression, although this cannot be attributed to any alteration in the plasma pharmacokinetics of ZD9331. Therefore, it may be necessary to administer a reduced dose of ZD9331 to patients with impaired renal function.     

Cytokine release in healthy donors and patients with chronic granulomatous disease upon stimulation with Aspergillus fumigatus

The release of tumour necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and IL-10 upon stimulation with non-viable conidia and hyphal fragments from Aspergillus fumigatus was investigated in an ex vivo whole-blood model. In healthy volunteers, high numbers of conidia (between 10(6) and 3 x 10(8)/ml) induced a moderate release of TNF-alpha and IL-6. Hyphal fragments (2.5 x 10(5)/ml) were more potent in stimulating the release of these pro-inflammatory cytokines. Although some IL-10 release was observed upon stimulation with either conidia or hyphal fragments, it was not significantly different from that in unstimulated controls. In comparison, in whole blood obtained from 4 patients with chronic granulomatous disease (CGD), a high release of pro-inflammatory cytokines together with a significantly higher IL-10 release than in the healthy controls was seen after stimulation with A. fumigatus. In conclusion, A. fumigatus can trigger the release of pro-inflammatory cytokines in a human whole-blood system, which is likely to be central to the activation of antifungal defence mechanisms. In contrast, A. fumigatus stimulates a higher release of anti-inflammatory cytokines in CGD patients, which may suggest that a dysregulation between pro- and anti-inflammatory cytokines contributes to the increased susceptibility to invasive aspergillosis in this patient group.     

Irinotecan pharmacokinetics-pharmacodynamics: the clinical relevance of prolonged exposure to SN-38

We have shown previously that the terminal disposition half-life of SN-38, the active metabolite of irinotecan, is much longer than earlier thought. Currently, it is not known whether this prolonged exposure has any relevance toward SN-38-induced toxicity. Here, we found that SN-38 concentrations present in human plasma for up to 3 weeks after a single irinotecan infusion induce significant cytotoxicity in vitro. Using pharmacokinetic data from 26 patients, with sampling up to 500 h, relationships were evaluated between systemic exposure (AUC) to SN-38 and the per cent decrease in absolute neutrophil count (ANC) at nadir, or by taking the entire time course of ANC into account (AOC). The time course of SN-38 concentrations (AUC(500 h)) was significantly related to this AOC (P<0.001). Based on these findings, a new limited-sampling model was developed for SN-38 AUC(500 h) using only two timed samples: AUC(500 h)=(6.588 x C(2.5 h))+(146.4 x C(49.5 h))+15.53, where C(2.5 h) and C(49.5 h) are plasma concentrations at 2.5 and 49.5 h after start of infusion, respectively. The use of this limited-sampling model may open up historic databases to retrospectively obtain information about SN-38-induced toxicity in patients treated with irinotecan.     

Case Reports. Chronic and acute Aspergillus meningitis

Cerebral aspergillosis usually occurs in severely immunocompromized hosts, is difficult to diagnose, and has a poor prognosis. After 14 months of chronic meningitis, ventriculitis, choroid plexitis, and lumbar arachnoiditis, which was complicated by acute hydrocephalus, Aspergillus, suspected to be from the candidus group, was isolated from the cerebrospinal fluid (CSF) of a previously healthy man. Thereafter Aspergillus antigen was found in stored plasma and CSF samples. He was treated with voriconazole and itraconazole. In a haemodialysis patient affected by an acute meningococcal meningitis, following a 3-day symptom-free interval, symptoms and signs of acute meningitis had reappeared and were unresponsive to a broad antimicrobial coverage. However, they resolved within 5 days after liposomal amphotericin B treatment had been started. From his CSF Aspergillus-DNA was identified and Aspergillus fumigatus isolated by culture. These two different clinical cases show that Aspergillus-DNA and antigen detection tests represent an advance in the diagnosis and liposomal amphotericin B, voriconazole, and itraconazole are an advance in the treatment of Aspergillus meningitis.     

Phase I and pharmacological study of the oral farnesyltransferase inhibitor SCH 66336 given once daily to patients with advanced solid tumours

A single-agent dose-escalating phase I study on the farnesyl transferase inhibitor SCH 66336 was performed to determine the safety profile and recommended dose for phase II studies. Plasma pharmacokinetics were determined as well as the SCH 66336-induced inhibition of farnesyl protein transferase in vivo. SCH 66336 was given orally once daily (OD) without interruption to patients with histologically-confirmed solid tumours. Routine antiemetics were not prescribed. 12 patients were enrolled into the study. Dose levels studied were 300 mg (6 patients) and 400 mg (6 patients) OD. Pharmacokinetic sampling was performed on days 1 and 15. Although at 400 mg OD only 1 patient had a grade 3 diarrhoea, 3 out of 6 patients interrupted treatment early due to a combination of various grade 1-3 toxicities (diarrhoea, uremiacreatinine, asthenia, vomiting, weight loss) indicating that this dose was not tolerable for a prolonged period of time. At 300 mg OD, the same pattern of toxicities was observed, but all were grade 1-2. Therefore, this dose can be recommended for phase II studies. Pharmacokinetic analysis showed that peak plasma concentrations as well as the AUCs were dose-related, with increased parameters at day 15 compared with day 1, indicating some accumulation upon multiple dosing. Plasma half-life ranged from 5 to 9 h and appeared to increase with increasing dose. Steady state plasma concentrations were attained by day 14. A large volume of distribution at steady state suggested extensive distribution outside the plasma compartment. There is evidence of inhibition of protein prenylation in some patients after OD oral administration of SCH 66336. SCH 66336 can be safely administered using a continuous oral OD dosing regimen. The recommended dose for phase II studies using this regimen is 300 mg OD.