Synthesis, structure-activity relationship and trypanocidal activity of pyrazole-imidazoline and new pyrazole-tetrahydropyrimidine hybrids as promising chemotherapeutic agents for Chagas disease.

Drug therapy for Chagas disease remains a major challenge as potential candidate drugs have failed clinical trials. Currently available drugs have limited efficacy and induce serious side effects. Thus, the discovery of new drugs is urgently needed in the fight against Chagas' disease. Here, we synthesized and evaluated the biological effect of pyrazole-imidazoline (1a-i) and pyrazole-tetrahydropyrimidine (2a-i) derivatives against relevant clinical forms of Trypanosoma cruzi. The structure-activity relationship (SAR), drug-target search, physicochemical and ADMET properties of the major active compounds in vitro were also assessed in silico. Pyrazole derivatives showed no toxicity in Vero cells and also no cardiotoxicity. Phenotypic screening revealed two dichlorinated pyrazole-imidazoline derivatives (1c and 1d) with trypanocidal activity higher than that of benznidazole (Bz) against trypomastigotes; these were also the most potent compounds against intracellular amastigotes. Replacement of imidazoline with tetrahydropyrimidine in the pyrazole compounds completely abolished the trypanocidal activity of series 2(a-i) derivatives. The physicochemical and ADMET properties of the compounds predicted good permeability, good oral bioavailability, no toxicity and mutagenicity of 1c and 1d. Pyrazole nucleus had high frequency hits for cruzipain in drug-target search and structure activity relationship (SAR) analysis of pyrazole-imidazoline derivatives revealed enhanced activity when chlorine atom was inserted in meta-positions of the benzene ring. Additionally, we found evidence that both compounds (1c and 1d) have the potential to interact non-covalently with the active site of cruzipain and also inhibit the cysteine proteinase activity of T. cruzi. Collectively, the data presented here reveal pyrazole derivatives with promise for further optimization in the therapy of Chagas disease.

Dose-intense PEFG (cisplatin, epirubicin, 5-fluorouracil, gemcitabine) in advanced pancreatic adenocarcinoma: a dose-finding study.

The aim of this study was to assess the maximum tolerated dose (MTD) of an intensified PEFG regimen administered every 14 days to patients with Stage III or metastatic pancreatic adenocarcinoma. Twenty-nine patients received fixed doses of both epirubicin (30 mg/m2) and 5-fluorouracil (200 mg/m2/day on Days 1-14) and of escalating doses of cisplatin and gemcitabine. The MTD was cisplatin 30 mg/m2 and gemcitabine 800 mg/m2. With respect to classical PEFG, intensified regimen potentially improved the dose-intensity of both cisplatin and epirubicin by 50 percent and of gemcitabine by 33 percent, reduced Grade 3-4 haematological toxicity and the number of outpatient accesses.

Dose-intense PEFG (cisplatin, epirubicin, 5-fluorouracil, gemcitabine) in advanced pancreatic adenocarcinoma.

BACKGROUND: PEFG regimen (cisplatin and epirubicin 40 mg/m2 day 1, gemcitabine 600 mg/m2 days 1 and 8, 5-fluorouracil (FU) 200 mg/m2/day continuous infusion) significantly improved the outcome of patients with advanced pancreatic adenocarcinoma (PA) with respect to standard gemcitabine in a previous phase III trial. This regimen was subsequently modified in a dose-finding study by increasing dose intensity of cisplatin and epirubicin (both at 30 mg/m2 every 14 days) and of gemcitabine (at 800 mg/m2 every 14 days). Results of a consecutive series treated by dose-intense PEFG regimen are herewith reported. MATERIAL AND METHODS: Dose-intense PEFG was administered to chemotherapy-naive patients with stages III-IV PA, < 75 years, performance status (PS) > 50, till progressive disease or for a maximum of 6 months. RESULTS: Between January 2004 and June 2005, 49 (31 or 63% metastatic) patients, median age 62 years, median PS 80, were treated with dose-intense PEFG. Partial response and stable disease was observed in 24 (49%) and 16 (33%) patients, respectively; 31 patients were progression-free at 6 months (PFS-6 = 63%). Median survival was 10.5 months and 1-year overall survival (OS) was 48% (95% confidence interval: 33-61%). Main grade 3-4 toxicity was: neutropenia in 26% of patients, stomatitis and fatigue in 8%, anaemia, diarrhoea, nausea/vomit in 6%, febrile neutropenia and thrombocytopaenia in 4%, hand-foot syndrome in 2%. CONCLUSION: When compared with 84 patients treated by classical PEFG at the same institution, dose-intense PEFG was not inferior in terms of PFS-6 (63 versus 57%), 1-year OS (48 versus 42%) and response rate (49 versus 49%); it allowed to increase dose intensity for gemcitabine by 32%, for cisplatin and epirubicin by 36% (FU reduced by 3%), to significantly reduce grade 3-4 hematological toxicity (neutropenia: 26 versus 86%; P < 0.00001; thrombocytopaenia: 4 versus 58%; P < 0.00001) and to reduce by one-third the number of outpatient accesses. The new PEFG schedule appears more suitable for clinical use and should be preferred as a basis for further development of therapeutic strategies against pancreatic cancer.

The pharmacokinetics of liposomal encapsulated daunorubicin are not modified by HAART in patients with HIV-associated Kaposi's sarcoma.

PURPOSE: To investigate the pharmacokinetics of liposomal daunorubicin (DaunoXome) administered alone or in combination with antiviral therapy including protease inhibitors (PI) to HIV-positive patients affected by Kaposi's sarcoma (KS). PATIENTS AND METHODS: A group of 18 patients with extensive or rapidly progressing AIDS-related KS received DaunoXome at a dose of 40 mg/m2 alone or in association with a triple combination therapy consisting of one PI plus two nucleoside reverse transcriptase inhibitors (NRTI). Daunorubicin pharmacokinetics were determined in a total of 23 cycles, 6 with DaunoXome alone, 9 in combination with indinavir, 6 with ritonavir and 2 with saquinavir. Plasma samples were obtained at different times during the 72 h after DaunoXome administration. Daunorubicin and daunorubicinol plasma levels were determined by high-performance liquid chromatography. RESULTS: After the DaunoXome infusion, daunorubicin was rapidly cleared from the body following, in most cases, a one-compartment open kinetic model. The daunorubicin peak concentrations, clearances and elimination half-lives were (means +/- SD): 16.3 +/- 2.8 microg/ml, 0.3 +/- 0.1 l/h per m2 and 5.6 +/- 2.6 h after DaunoXome alone; 15.1 +/- 4.9 microg/ml, 0.5 +/- 0.3 l/ h per m2 and 5.8 +/- 2.1 h after the combination with indinavir; and 14.5 +/- 2.8 microg/ml, 0.4 +/- 0.2 l/h per m2 and 6.5 +/- 3.9 h after the combination with ritonavir. In all groups, daunorubicinol plasma levels were approximately 25-30 times lower than those of the parent drug. CONCLUSION: Our data show that there are no significant differences in the pharmacokinetic parameters of daunorubicin in patients receiving DaunoXome in combination with indinavir and ritonavir compared with those in patients not receiving PIs. Therefore in patients affected by AIDS-related KS treated with Highly Active AntiRetroviral Therapy (HAART) there is no pharmacokinetic justification for reducing the doses of DaunoXome.

Correlation between pretreatment serum levels of neopterin and response to interleukin-2 immunotherapy in cancer patients.

IL-6 levels have been proven to correlate with resistance to IL-2 immunotherapy. Since IL-6 may be produced by both macrophages and TH2 lymphocytes, it is not possible to establish whether the negative prognostic significance of IL-6 levels may primarily depend on an enhanced macrophage or TH2 activation. Macrophage activation may be documented by the increase in its specific marker neopterin. In an attempt to establish whether the negative significance of IL-6 high levels prior to IL-2 immunotherapy may reflect an enhanced macrophage activation, we have investigated the relation existing between pretreatment concentrations of neopterin and response to IL-2 immunotherapy in cancer patients. The study included 20 metastatic renal cell cancer patients, who were treated with IL-2 subcutaneously at 6 million IU/day for 5 days/week for 6 weeks. Before the onset of IL-2 therapy, abnormally high serum levels of neopterin were seen in 11/20 patients. Moreover, neopterin concentrations were significantly correlated with those of IL-6. Tumor regression rate was significantly higher in patients with normal than in those with elevated levels of neopterin prior to therapy (5/9 vs 1/11, P < 0.05), as well as the percent of the survival at 1 year (9/9 vs 4/11, P < 0.01). This preliminary study would suggest that pretreatment values of the macrophage marker neopterin correlate with resistance to IL-2 cancer immunotherapy.

Neuroimmunotherapy with low-dose subcutaneous interleukin-2 plus melatonin in AIDS patients with CD4 cell number below 200/mm3: a biological phase-II study.

A phase-II pilot clinical study was performed to evaluate the effects of low-dose subcutaneous IL-2 with the pineal hormone melatonin (MLT) in AIDS patients with CD4 counts below 200/mm3. The study included 11 patients. IL-2 was given subcutaneously at 3 million IU/ day in the evening for 6 days/week for 3 weeks. MLT was given orally at 40 mg/day in the evening every day, starting 7 days prior to IL-2. The treatment was substantially well tolerated, and in particular no cardiovascular or pulmonary complication occurred. An increase in CD4 cell number greater than 30% occurred in 4/11 (36%) patients, and CD4 cell mean values observed during the study were significantly higher with respect to those found before. In addition, the treatment induced a significant increase in mean number of lymphocytes, eosinophils, T lymphocytes, NK cells, CD25- and DR-positive lymphocytes. Finally, CD4/CD8 mean ratio significantly increased during the study. This preliminary clinical study suggests that the combined neuroimmunotherapy with low-dose subcutaneous IL-2 and MLT may improve the immune status also in AIDS patients with CD4 cell counts below 200/mm3, who generally do not respond to IL-2 alone.

Relation between macrophage and T helper-2 lymphocyte functions in human neoplasms: neopterin, interleukin-10 and interleukin-6 blood levels in early or advanced solid tumors.

At present, it is known that there are two main mechanisms responsible for cancer-related immunosuppression, mediated by macrophages and by TH2 lymphocytes. The relation existing between macrophage- and TH2-mediated immunosuppression still remains to be understood. The present study was performed in an attempt to establish which is the correlation existing in cancer patients between IL-10 and neopterin levels, which reflect TH2- and macrophage-mediated suppressive events, respectively. The study included 40 solid tumor patients and 60 healthy subjects as controls. Serum concentrations of neopterin and IL-10 were measured by the RIA method and by an immuno-enzymetric assay, respectively. Because of its possible production both by TH2 and macrophages, serum levels of IL-6 were also determined. Neopterin, IL-10 IL-6 mean concentrations were significantly higher in cancer patients than in controls. Mean values of both neopterin and IL-6 were significantly higher in metastatic patients than in those with locally limited disease. IL-10 mean levels were also significantly higher in patients with metastatic disease. IL-6 levels were significantly correlated with those of neopterin, whereas no correlation was found between neopterin and IL-10 values. This preliminary study would suggest that macrophage- and TH2-mediated immunosuppression may occur independently in solid tumors, and that it becomes more evident with disease progression.

[Lymphocyte levels before treatment with subcutaneous interleukin-2 and during maintenance treatment in relation to the clinical efficacy in metastatic renal carcinoma]. / Valori linfocitari pre-terapia con Interleuchina-2 sottocutanea e durante terapia di mantenimento in relazione all'efficacia clinica nel carcinoma renale metastatico.

AIMS AND BACKGROUND: the antitumor activity of IL-2 is mediated by an increase in lymphocyte number. Moreover, our previous studies have shown that therapy for 1 week/month with low-dose subcutaneous IL-2 is sufficient to maintain high levels of lymphocytes in cancer patients who have had tumor regression or stable disease (SD) in response to IL-2 immunotherapeutic cycles. This study was performed to establish whether tumor progression in cancer patients chronically treated with IL-2 may be associated with lymphocyte number decline. METHODS: the study included 60 metastatic renal cell patients, who were treated with 2 induction cycles of IL-2 subcutaneous immunotherapy (6 million IU/day for 5 days/week for 6 weeks, corresponding to one cycle). Tumor regression occurred in 17/60 patients, 23 patients a SD, and the remaining 20 cases progressed. Non-progressed patients (n = 40) underwent a maintenance therapy consisting of one week of therapy every month. After a median follow-up of 18 months, 29/40 patients with response or SD had progressed. The immune investigation consisted of lymphocyte, T lymphocytes, NK cell number determination and sCD25 level detection. RESULTS: the mean number of lymphocytes, T lymphocytes and NK cells observed on IL-2 maintenance therapy was significantly higher than that seen before beginning the immunotherapy. Moreover, mean number of lymphocytes and mean levels of sCD25 observed at the time of tumor progression were respectively lower and higher than those seen on maintenance therapy in the same patients, without, however, significant differences. CONCLUSION: despite the importance of lymphocytes in mediating the antitumor activity of IL-2, this study shows that tumor progression in cancer patients chronically treated with low-dose IL-2 after response or SD during IL-2 induction cycles is not associated with a significant decline in lymphocyte, T lymphocyte or NK cell numbers. Further studies, carried out to analyze the functional status of immune cells at the time of tumor progression, will be necessary to define the role of immunity in cancer patients progressing under IL-2 chronic therapy.

Germline polymorphisms in EGFR and survival in patients with lung cancer receiving gefitinib.

The purpose of this study was to evaluate associations between germline epidermal growth factor receptor (EGFR) variants involved in transcriptional regulation and overall survival in white patients with non-small-cell lung cancer (NSCLC) treated with the EGFR tyrosine kinase inhibitor, gefitinib. Of 175 consecutive patients treated with oral gefitinib (250 mg/day), 170 (median age: 67 years; 72% men) were evaluable for genotyping and survival. Fifty-five patients (33%) had stable disease and 17 (10%) had an objective response. The most common of four haplotypes was G-C (EGFR*1) at the EGFR -216G>T and -191C>A loci (frequency, 0.45). After adjusting for performance status, previous platinum-containing chemotherapy and occurrence of skin rash or diarrhea during the first treatment cycle in patients with performance status 0 or 1 (N=139), the absence of EGFR*1 was associated with significantly better survival (hazard ratio: 0.54; 95% confidence interval: 0.32-0.91; P=0.015). The results may help identify patients with NSCLC who can benefit from gefitinib treatment.

The good and evil of HAART in HIV-related progressive multifocal leukoencephalopathy.

The use of highly active anti-retroviral therapy in patients with HIV-related progressive multifocal leukoencephalopathy is associated with increased survival and disease stabilization. However, approximately half of the patients receive no benefit from these treatments. In a group of HIV-infected patients with histologically or virologically confirmed PML, we recognized two distinct patterns of response, i.e., long survivors versus nonresponders, but could not identify any factors at baseline predictive of PML outcome. In addition, the use of cidofovir did not substantially affect survival. However, the survival rate was higher during the first years of HAART, i.e., 1996-1997, with better outcomes observed in patients receiving a protease inhibitor-containing regimen either irregularly or after a switch from a 2-nucleoside reverse transcriptase inhibitor combination. In contrast, PML outcome was frequently poor in both HAART-naive and -experienced patients who responded promptly to anti-HIV therapy in terms of CD4 increase and viral load decrease. In addition, in a number of patients, PML onset was temporally associated with immune reconstitution. It may be that, in some patients, rapid immune reconstitution due to HAART paradoxically worsens the course of PML. Gradual reversal of immune deficiency might be associated with better outcome.