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Dipeptidyl-peptidase-4 (DPP-4) inhibitors are a relatively new class of non-insulin glucose-lowering agents, belonging to the incretin family, which are able to improve glycemic control with a favorable safety profile, since they are associated with a low risk of hypoglycemia, no weight gain, and good tolerability in patients with chronic renal failure. Some experimental and clinical studies suggest that these drugs may exert significant pleiotropic effects, in particular on chronic kidney disease (CKD) progression, but data from clinical trials are still controversial. In an effort to clarify the effects of DPP-4 inhibitors (DPP-4is) on diabetes-related renal damage, we performed a narrative review of available clinical trials and other experimental studies focusing on renal effects of DPP-4is. Currently, there is no conclusive evidence proving the usefulness of this drug class for improving diabetes-related renal damage. However, our literature review suggests that DPP-4is are safe and well tolerated in type 2 diabetes mellitus (T2DM) patients with CKD. More importantly, results from the reviewed studies indicate that DPP-4 inhibitor therapy may improve two major risk factors for diabetic nephropathy, such as hyperglycemia and albuminuria, resulting in potential renal benefits beyond glycemic control. Despite several limitations, the conclusions of our review corroborate previous evidence on the potential renal benefits of DPP-4is, highlighting the urgent need of future trials adequately powered and designed on hard renal outcomes to ascertain (or contradict) the therapeutic benefit of DPP-4is in T2DM and CKD patients.

e13522 Background: Immunotherapy is a promising approach for the treatment of brain tumors, but available data are still inconclusive. The main drawback is represented by transport across the blood–brain barrier of high molecular weight drugs. Convection-enhanced delivery (CED) has been designed to overcome some difficulties. We wondered whether a CED strategy based on the use of novel immune checkpoint inhibitors could be effective. Methods: Frameless biopsy by fluorescein tracer and neuronavigation-assisted system, followed by an injection of nivolumab 40mg/4mL into the brain lesion, were offered to patients with: a) high grade gliomas (HGG) inoperable or progressed during or after standard treatment (i.e. surgery and radio-chemotherapy); b) HGG at first diagnosis or after disease progression treated with radical surgery (nivolumab delivered in the surgical cavity after tumor removal); c) other brain tumors or solitary metastases judged suitable for surgical procedure. PD-L1 expression was assessed in all patients, but it was not a strict criterion for accrual. Standard therapy, usually based on chemotherapy, radiotherapy or both, was sequentially administered to patients able to tolerate such an approach. End-points were safety, response rate, disease control, predictive value of PD-L1 expression. This is a non-sponsored monocentric, real life, basket trial approved by Ethical Committee (EudraCT number: 2018-001560-33). Results: Since August 2018, 17 patients with brain tumors (16 HGG and 1 heavily pretreated medulloblastoma) and 5 patients with brain metastasis (of lung and gastrointestinal cancers) were enrolled. Median age was 63 years (range 26-83). After a median follow up of three months (range 1-6), all patients are alive and in good clinical conditions. No signs of neurologic toxicity due to intracerebral nivolumab were observed. Brain MRI performed at 4 to 12 weeks after nivolumab CED revealed findings suggesting a perivascular lymphocyte infiltration. Correlation between PD-L1 expression and treatment efficacy will be evaluated over time. Conclusions: Intracerebral nivolumab appears to be a feasible and safe option for patients with HGG and brain metastases at the dose investigated in the study. Long-term follow up could contribute to well understand the role of this strategy. Clinical trial information: 2018-001560-33.

Soft tissue sarcomas (STS) are rare tumors with mesenchymal origin, accounting for 1% of all human cancer. Local control of STS can be obtained through the use of surgery and radiotherapy. In about 40% of these patients, disease will recur at distant sites, and of these more than 90% will die because of this aggressive malignancy. In advanced and/or metastatic STS patients treated with anthracycline-based regimen the median overall survival is about 12 months, and it has remained unchanged during the last 20 years. Clearly, this strongly suggests the need for discover more active compounds in STS, such as imatinib in GIST or dermatofibrosarcoma patients. In this paper we describe the crucial role of angiogenesis mechanisms in sarcomas development and progression. Consequentially, we focus on pazopanib, a novel multitargeted tyrosine kinase inhibitor with anti-angiogenic activity, mainly due to VEGFR2 pathway interference. We also analyze principal completed trials leading pazopanib approval in sarcomas pretreated patients.

It is known that the 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) are effective in both the primary and the secondary prevention of ischemic heart disease. Increasing evidence indicates that statins have protective effects in several neurological diseases including stroke, cerebral ischemia, Parkinson disease, multiple sclerosis, traumatic brain injury and epilepsy. The aim of the present research was to evaluate the effects of some HMG-CoA reductase inhibitors (i.e. lovastatin, simvastatin, atorvastatin, fluvastatin and pravastatin) commonly used for the treatment of hypercholesterolemia in the DBA/2 mice, an animal model of generalized tonic-clonic seizures. Furthermore, the co-administration of these compounds with some antiepileptic drugs (AEDs; i.e. carbamazepine, diazepam, felbamate, gabapentin, lamotrigine, levetiracetam, oxcarbazepine, phenobarbital, phenytoin, topiramate and valproate) was studied in order to identify possible positive pharmacological interactions. Simvastatin only was active against both the tonic and clonic phase of audiogenic seizures, whereas the other statins tested were only partially effective against the tonic phase with the following order of potency: lovastatin>fluvastatin>atorvastatin; pravastatin was completely ineffective up to the dose of 150mg/kg. The co-administration of ineffective doses of all statins with AEDs generally increased the potency of the latter reducing their ED50 values. In particular, simvastatin was the most active in potentiating the activity of AEDs and the combinations of statins with carbamazepine, diazepam, felbamate, lamotrigine, topiramate and valproate were the most favorable, whereas, the co-administrations with the other AEDs studied was in most cases neutral. The increase in potency was generally associated with an enhancement of motor impairment (TD50); however, the therapeutic index (TD50/ED50) of combined treatment of AEDs with statins was predominantly more favorable than control. Statins administration did not significantly affect the total plasma but, in some cases, it increased the free plasma levels and the brain concentrations of some of the AEDs studied (i.e. carbamazepine, diazepam, phenytoin and valproate); however, these alterations where not statistically significant. Therefore, with the exception of the latter compounds, we might exclude pharmacokinetic interactions and conclude that for the most of AEDs, potentiation was of pharmacodynamic nature. In conclusion, simvastatin, fluvastatin, lovastatin and atorvastatin showed an additive anticonvulsant effect when co-administered with some AEDs, most notably carbamazepine, diazepam, felbamate, lamotrigine, topiramate and valproate, implicating a possible therapeutic relevance of such drug combinations. The present results suggest that statins, besides the beneficial cardiovascular effects, might be able to affect brain areas, which might participate in the regulation of seizure susceptibility.

Aripiprazole (APZ) is regarded as a first-line atypical antipsychotic used for the treatment of first and multiple episodes of schizophrenia to improve positive- and negative-symptoms. Its therapeutic indications were extended to acute manic and mixed episodes associated with bipolar disorder. In addition, APZ was approved as an adjunct therapy for major depressive disorder in 2007. Compared to other antipsychotic drugs, APZ has a unique pharmacological profile. It is a partial agonist at D₂ dopamine receptors and serotonin 5-HT(1A) and 5-HT₇ receptors, whereas it is an antagonist at serotonin 5-HT(2A) and 5-HT₆ receptors. Since epilepsy is often accompanied with neurological comorbidities such as depression, anxiety and cognitive deficits caused by both the disease and/or drug treatment, we wished to examine the effects of a sub-chronic treatment (>14 consecutive days) with APZ (0.3, 1 and 3 mg/kg; i.p.) on both absence seizures and WAG/Rij rat's behavior using different standard paradigms: Open field (OF) test, elevated plus maze (EPM) test, forced swimming (FS) test, sucrose consumption (SC) test and Morris water maze (MWM). WAG/Rij rats represent a validated genetic animal model of absence epilepsy with mild-depression comorbidity, also including other behavioral alterations. APZ treatment showed some anti-absence properties and regarding the behavioral comorbidity in this rat strain, we observed that APZ possesses clear antidepressant effects in the FS and SC tests also increasing memory/learning function in the Morris water maze test. In the two anxiety models used, APZ showed only minor effects. In conclusion, our results indicate that APZ might actually have a potential in treating absence seizures or as add-on therapy but more interestingly, these effect might be accompanied by positive modulatory actions on depression, anxiety and memory which might be also beneficial in other epileptic syndromes. This article is part of a Special Issue entitled 'Cognitive Enhancers'.

Hepatocellular carcinoma (HCC) remains a major global health problem and Calabria in the south of Italy is not an exception. Sorafenib is the first and only Food and Drug Administration approved drug for the treatment of advanced HCC and it is currently under intensive monitoring by the Health Authorities in Italy Agenzia Italiana del Farmaco. This general report has been developed with the aim of briefly reviewing the data found in the reports of adverse reactions (ADRs) collected in Calabria in 2012 for sorafenib treated patients. Extrapolated data have highlighted some differences between the adverse drug reactions reported in patients younger or older than 70 years and other important differences with the current approved leaflet. Several limitations might be present in data analysis form spontaneous reporting, however, the relevance of reporting ADRs (dermatitis, asthenia, vomiting, etc.) for the early identification of drug related signals has to be underlined.

It is currently known that erythrocytes are the major source of sphingosine 1-phosphate (S1P) in the body. S1P acts both extracellularly as a cellular mediator and intracellularly as an important second messenger molecule. Its effects are mediated by interaction with five specific types of G proteincoupled S1P receptor. Fingolimod, is a recognized modulator of S1P receptors, and is the first orally active disease-modifying therapy that has been approved for the treatment of multiple sclerosis. Magnetic resonance imaging data suggest that fingolimod may be effective in multiple sclerosis by preventing blood-brain barrier disruption and brain atrophy. Fingolimod might also possess S1P receptorindependent effects and exerts both anti-inflammatory and neuroprotective effects. In the therapeutic management of epilepsy, there are a great number of antiepileptic drugs, but there is still a need for others that are more effective and safer. S1P and its receptors might represent a suitable novel target also in light of their involvement in neuroinflammation, a well-known process underlying seizures and epileptogenesis. The objective of this manuscript is to review the biological role of S1P and its receptors, focusing on their expression, effects and possible involvement in epilepsy; furthermore, we summarize the possible anti-seizure properties of fingolimod and discuss its possible usefulness in epilepsy treatment. We conclude that fingolimod, being already commercially available, might be easily tested for its possible therapeutic effectiveness in epileptic patients, both after a more comprehensive evaluation of the real potential of this drug and following a clear evaluation of the potential role of its main targets, including the S1P signaling pathway in epilepsy.

The usage of dietary supplements and other natural products to treat neurological diseases has been growing over time, and accumulating evidence suggests that flavonoids possess anticonvulsant properties. The aim of this study was to examine the effects of a flavonoid-rich extract from orange juice (OJe) in some rodent models of epilepsy and to explore its possible mechanism of action. The genetically audiogenic seizures (AGS)-susceptible DBA/2 mouse, the pentylenetetrazole (PTZ)-induced seizures in ICR-CD1 mice and the WAG/Rij rat as a genetic model of absence epilepsy with comorbidity of depression were used. Our results demonstrate that OJe was able to exert anticonvulsant effects on AGS-sensible DBA/2 mice and to inhibit PTZ-induced tonic seizures, increasing their latency. Conversely, it did not have anti-absence effects on WAG/Rij rats. Our experimental findings suggest that the anti-convulsant effects of OJe are likely mediated by both an inhibition of NMDA receptors at the glycine-binding site and an agonistic activity on benzodiazepine-binding site at GABAA receptors. This study provides evidences for the antiepileptic activity of OJe, and its results could be used as scientific basis for further researches aimed to develop novel complementary therapy for the treatment of epilepsy in a context of a multitarget pharmacological strategy.

Study Type – Therapy (individual cohort) Level of Evidence 2b What's known on the subject? and What does the study add? Sorafenib is an oral receptor tyrosine kinase inhibitor that inhibits RAF serine/threonine kinases and receptor tyrosine kinases (vascular endothelial growth factor receptors 1, 2, 3 and platelet-derived growth factor-beta, Flt-3 and c-kit) that are implicated in tumourigenesis and tumour progression. Sorafenib is approved for the treatment of advanced renal cell cancer. B-RAF mutations (V600E and K601E) may be interesting negative predictive markers in metastatic kidney cancer patients treated with Sorafenib. Larger trials are needed to validate this hypothesis and should include B-RAF molecular analysis for better patient selection. OBJECTIVE • To assess both clinical and biological efficacy and toxicity of sorafenib in patients with metastatic renal cell carcinoma (mRCC) previously treated with an anti-angiogenic vascular endothelial growth factor receptor (VEGFR) tyrosine kinase inhibitor. METHODS • Sorafenib is an orally active multikinase inhibitor approved for the treatment of mRCC. • Drug-focused translational research on tissues (i.e. B-RAF) and plasma (VEGFR-α, circulating endothelial cells, endothelial progenitor cells) was performed to define biological predictive and prognostic markers and their related kinetics. • Patients with mRCC pretreated with an anti-angiogenic treatment, an Eastern Cooperative Oncology Group performance status (ECOG PS) of 0–2 and adequate organ function were eligible. • Patients received sorafenib 400 mg twice a day continuously in 4-week cycles. Patients with no progressive disease at 12 weeks continued to receive sorafenib at the standard dose, whereas progressing patients received an increased dose (600 mg twice a day) with early disease restaging after 4 weeks. Patients who progressed at 600 mg twice a day went off study. Efficacy (overall tumour control) was assessed by Response Evaluation Criteria in Solid Tumors. RESULTS • In all, 19 patients were entered. The baseline characteristics were as follows: ECOG PS 0–1 94.8%; median (range) age 62 (41–81) years; nephrectomy 100%; surgery for metastatic disease 26.4%; clear cell 79.1%; papillary cell 15.7%; sarcomatoid/high grade 5.2%; two or more metastatic sites 84%. • Overall, 11 patients (58%) had disease control at 6 months without significant correlation between response to prior therapy and hypertension. Progression-free survival (PFS) of 8.3 months was observed. • Of six patients for whom the dose was escalated due to early progression, three benefitted with PFS of >3 months. Three (15.7%) of 19 patients had a V600E mutation and one had a K601E mutation; PFS appeared to be substantially shorter in these patients compared with 15 patients with wild-type B-RAF (2.5 vs 9.1 month, P < 0.05). • The most common toxicity (National Cancer Institute Common Toxicity Criteria, NCIC 3.0, all patients) was grade ≥1 diarrhoea and grade 2–3 hand–foot syndrome in 11 patients. Grade 3 mucositis was observed in one patient. CONCLUSIONS • Sorafenib at doses of 400–600 mg twice a day continuously results in acceptable and well tolerated salvage treatment after VEGFR tyrosine kinase inhibitor failure. • In progressive patients, treatment with a higher dose could be a valid option and B-RAF mutations may be an interesting predictive marker to be studied in a larger randomized trial.

Purpose: Depression is most commonly associated withepilepsy. Recent reports have suggested a putative rela-tionship between seizure development and onset ofdepressive behavior, whereas others proposed that twoclinicalentitiesmightrepresentdifferentneuropathologicaspectsofthesameneurologicdisorder.TheWAG/Rijratabsence epilepsy model has also been proposed as a suit-able model to test antidepressant drugs. We previouslyreported on a long-term study of two antiepileptic drugs(AEDs)toassesstheirprotectiveroleinabsenceepilepto-genesis.Here,weexaminedtheeffectsoflong-termtreat-ment with several AEDs on absence seizure developmentand onset of depressive-like behavior in WAG/Rij rats atdifferentages,usingaforcedswimmingtest(FST).Methods: Animals were divided into one untreatedcontrol group and four test groups, given ethosuximide,levetiracetam, zonisamide, or carbamazepine. Electro-encephalography (EEG) readings were recorded at 6.5monthsofage.Key Findings: Ethosuximide-treated animals showed sig-nificant reductions in recorded spike-wave discharges(SWDs), and FST immobility time (IT) compared withuntreated same age controls. However, zonisamide- andcarbamazepine-treated animals had IT values similar tothose of controls, but only zonisamide significantlydecreased absence seizure development. Carbamazepineincreased SWD incidence. Levetiracetam also protectedagainst seizure development, while augmenting IT, sug-gestingaprodepressiveeffect.Significance: Although treatment with ethosuximide, lev-etiracetam, or zonisamide reduced appearance of SWDsinWAG/Rijrats,thiswasnotgenerallylinkedtoareducedonset of depressive characteristics, as assessed by FST.Therefore, expression of depressive-like behavior seemsunrelated to seizure control in this model. Some possiblealternative explanations for the observed data are dis-cussed.KEY WORDS: Absence epilepsy, Antiepileptic drugs,Spike wave discharges, Depression, Forced swimmingtest,WAG/Rijrats.

The design and synthesis of new N1-substituted 3-carboxy- and 3-phosphonopyrazoline and pyrazole amino acids that target the glutamate binding site of NMDA receptors are described. An analysis of the stereochemical requirements for high-affinity interaction with these receptors was performed. We identified two highly potent and selective competitive NMDA receptor antagonists, (5S,alphaR)-1 and (5S,alphaR)-4, which exhibit good in vitro neuroprotective activity and in vivo anticonvulsant activity by i.p. administration, suggesting that these molecules may have potential use as therapeutic agents.

Summary Purpose: Epilepsy is a heterogeneous syndrome characterized by recurrent, spontaneous seizures; continuous medication is, therefore, necessary, even after the seizures have long been suppressed with antiepileptic drug (AED) treatments. The most disturbing issue is the inability of AEDs to provide a persistent cure, because these compounds generally suppress the occurrence of epileptic seizures without necessarily having antiepileptogenic properties. The aim of our experiments was to determine, in the WAG/Rij model of absence epilepsy, if early long-term treatment with some established antiabsence drugs might prevent the development of seizures, and whether such an effect could be sustained. Methods: WAG/Rij rats were treated for ∼3.5 months (starting at 1.5 months of age, before seizure onset) with either ethosuximide (ETH; drug of choice for absence epilepsy) or levetiracetam (LEV; a broad-spectrum AED with antiabsence and antiepileptogenic properties). Results: We have demonstrated that both drugs are able to reduce the development of absence seizures, exhibiting antiepileptogenic effects in this specific animal model. Discussion: These findings suggest that absence epilepsy in this strain of rats very likely follows an epileptogenic process during life and that early therapeutic intervention is possible, thereby opening a new area of research for absence epilepsy and AED treatment strategies.

N -Acetyl-1-(4-chlorophenyl)-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline (THIQ-10c) is a noncompetitive α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor antagonist that has been demonstrated to antagonize generalized tonic–clonic seizures in different animal models of epilepsy. In the study described here, we tested the potential effect of such a compound alone or co-administered with ethosuximide in a genetic animal model of absence epilepsy, the WAG/Rij rat. The intraperitoneal or intracerebroventricular microinjection of THIQ-10c alone was unable to significantly modify the number and duration of spike-and-wave discharges (SWDs). In contrast, intracerebroventricular administration of AMPA induced a dose-dependent increase in the number of SWDs. THIQ-10c dose-dependently antagonized this effect. Furthermore, co-administration of THIQ-1c with ethosuximide (50 mg/kg, intraperitoneally) was able to significantly increase the efficacy of the anti-absence drug. In conclusion, although noncompetitive AMPA receptor antagonists alone might not be useful in the treatment of absence epilepsy because of their low therapeutic index, combining them with ethosuximide might be helpful in controlling absence seizures in patients not tolerating this drug or in refractory patients.

The study aimed to assess the efficacy and safety of brostallicin, a new DNA minor groove binder, at a dose of 10 mg/m2, intravenous (i.v.) every three weeks, in patients with advanced or inoperable soft tissue sarcoma (STS) and gastrointestinal stromal tumour (GIST) failing first line therapy. Two groups were recruited: (1) GIST following treatment with imatinib; (2) other STS following treatment with single agent doxorubicin or ifosfamide or a single line of combination therapy. The primary end-point was overall response rate (ORR) as defined by response evaluation criteria in solid tumours (RECIST). Progression free survival (PFS) was a secondary end-point. In the GIST group, a Simon two step design was planned: first step 18 patients, total 32 patients (p1 = 20% p0 = 5% alpha = beta = 0.1). In the non-GIST group, planned sample size was 40 in a standard Fleming one-step design (p0 = 10%, p1 = 25%, alpha = beta = 0.1). Forty-three patients with non-GIST and 21 patients with GIST were recruited. In general, the drug was well tolerated. Common Toxicity Criteria (CTC) grade 3 or grade 4 toxicity was granulocytopenia: 70% of patients, 50% of cycles; fatigue: 25% of patients, 8% of cycles; febrile neutropenia: 14% of patients, 4% of cycles. There was one confirmed toxic death due to neutropenic septicaemia. Three patients had clinically significant allergic reactions in 249 cycles delivered. In the GIST group, no patients had a confirmed response and recruitment was discontinued at the first step. In the non-GIST group, there were two confirmed partial responses. The 3 month PFS was 46% in the non-GIST group and 33% in the GIST group. In the non-GIST group, this PFS is in the range of other agents considered active in STS, and may predict for more substantial first line activity. Further investigation in STS other than GIST appears warranted.

Inducible nitric oxide synthase knock-out (iNOS(-/-)) mice are valid models of investigation for the role of iNOS in patho-physiological conditions. There are no available data concerning neuroactive amino acid levels of iNOS(-/-) mice and their behaviour in response to pentylenetetrazole (PTZ). We found no significant differences in the convulsive dose 50 (CD(50)) between iNOS(-/-) and control (iNOS(+/+)) mice, however, iNOS(-/-) mice reach the kindled status more slowly than control, suggesting that in basal condition the GABA-benzodiazepine inhibitory inputs are unaltered by iNOS mutation. Clear differences between iNOS(+/+) and iNOS(-/-) mice amino acid concentrations were evident both in basal conditions and after kindling. Our results show that aspartate was significantly lower in all brain areas studied except the brain stem whereas glutamate and glutamine were significantly higher in the cortex, hippocampus and brain stem. GABA was slightly and not significantly higher in the cortex, hippocampus and brain stem, whereas taurine was significantly higher in all areas except diencephalon and glycine was significantly lower in the diencephalon and cerebellum. In this context, the inability of iNOS(-/-) mice to increase the NO levels following PTZ administrations indicate that NO might play a pro-epileptogenic role in the genesis and development of some types of epilepsy. Since there is no correlation between neurotransmitter levels and the development of kindling, it is possible to exclude that the difference between the two strains is due to an imbalance between the considered neurotransmitters, and it is then possible that this difference is due to the presence of iNOS, which might be involved in long term plasticity of the brain.

Neurosteroids are synthesized in the brain and have been demonstrated to modulate various cerebral functions. Allopregnanolone (3alpha-hydroxy-5alpha-pregnan-20-one), a naturally occurring neurosteroid, and ganaxolone (3alpha-hydroxy-3beta-methyl-5alpha-pregnan-20-one), a synthetic derivative, are two neurosteroids acting as positive allosteric modulators of the GABA(A) receptor complex acting on a specific steroid recognition site. Both agents antagonize generalized tonic-clonic seizures in various animal models of epilepsy. Pregnenolone sulphate (3beta-hydroxy-5alpha-pregnen-20-one 3-sulphate; PS) is a negative allosteric modulator of GABA(A) receptors and a positive modulator of the NMDA receptors. We have evaluated the effects of such compounds in a genetic animal model of absence epilepsy, the WAG/Rij rat. Animals were chronically implanted with five frontoparietal cortical electrodes for electrocorticogram (EEG) recordings and bilateral guide cannulae into specific brain areas of the cortico-thalamic circuit in order to evaluate the effects of these compounds on the number and duration of epileptic spike-wave discharges (SWDs). The focal and bilateral microinjection of the two GABA(A) positive modulators into some thalamic nuclei (nucleus ventralis posteromedialis, nucleus reticularis thalami, nucleus ventralis posterolateralis was usually able to significantly worsen the occurrence of SWDs in WAG/Rij rats. Whereas both compounds were able to reduce the number and duration of SWDs when microinjected into the peri-oral region of the primary somatosensory cortex. The effects of PS were more complex depending on both the dose and the site of administration, generally, at low doses in thalamic nuclei and cortex, PS induced an increase of absence activity and a reduction at higher doses. These findings suggest that neurosteroids might play a role in absence epilepsies and that it might depend on the involvement of specific neuronal areas.

Imatinib pharmacokinetics (PK) may be affected by a number of factors that are related to the disease being treated and to the response of that disease to imatinib. Patients in the phase I and phase II trials conducted by the EORTC in patients with gastrointestinal stromal tumours (GISTs) and other sarcomas had detailed blood sampling for imatinib PK on day 1 and on day 29. Patients with GISTs also had repeat sampling, using a limited sampling strategy, after approximately 12 months on therapy. This population PK study was carried out to examine what covariates affected imatinib PK in GIST patients and what PK changes occurred over time. In the model producing the best fit, low clearance (CL) correlated with low body weight and high granulocyte count, whereas low haemoglobin correlated with low volume of distribution. For a patient with 77% of the median body weight or with 1.87 times the median granulocyte count, the apparent CL is 6.53 l/h, about 70% of the typical apparent CL of 9.33 l/h; for a patient of 84% of the typical haemoglobin level, the volume of distribution is about 70%. Total white blood cell count correlated closely with granulocyte count and there was a moderate correlation between haemoglobin and albumin (r = 0.454). There was a trend towards increased imatinib clearance after chronic exposure over 12 months. The typical apparent CL increased 33% from day 1. Nevertheless, the approximate 95% confidence interval of the increase of the typical apparent CL was 33 +/- 34.6%, which contains zero. It is not yet clear whether this is a significant factor in the amelioration of imatinib toxicity that occurs with time or is related to disease control, and further work is required to confirm this observation.

Interleukin-6-deficient (IL-6 −/− ) mice and their normal littermate (WT) were studied to evaluate their susceptibility to seizures induced by electroshock and audiogenic stimuli at different ages. No significant changes in maximal electroshock susceptibility were evidenced between the two strains, while audiogenic seizures (AGS) can be induced only in IL-6 −/− mice. The effects of age and genetic condition on AGSs were evaluated. The behavioural and electrocortical changes during audiogenic stimulus were observed. In addition, the levels of neurotransmitter amino acids in five brain areas (of both strains) were measured at 60 days of age. Aspartate level significantly increased in the brain stem (BS) and hippocampus (HI), while it decreased in the diencephalon (DE) of IL-6 −/− mice. Glutamate content significantly decreased in the cerebellum (CB), DE and HI. GABA levels significantly decreased in all the areas studied. Glycine significantly decreased in the BS, CB and DE, while taurine decreased only in the DE. The levels of glutamine significantly decreased in all the areas examined, except in the cortex (CX). The changes of neuroactive amino acid levels, particularly in the BS, might explain the characteristic of high propensity to AGS of IL-6 −/− mice. The present data support the validity of IL-6 −/− mice as a novel epileptic model for the study of the pathophysiology and pharmacology of epilepsy.

In the present study, the susceptibility of knockout interleukin-6 (IL-6(-/-)) mice to various convulsant stimuli has been evaluated and compared with other three related mice strains. Animals were treated with chemical convulsants impairing the gamma-aminobutyric acid neurotransmission [pentylenetetrazole (PTZ), picrotoxin, bicuculline, methyl-6,7-dimethoxy-4-ethyl-beta-carboline-3-carboxylate (DMCM), methyl-beta-carboline-3-carboxylate (beta-CCM)], enhancing glutamatergic neurotransmission [N-methyl-d-aspartate (NMDA), alpha-amino-3 hydroxy-5-methyl-4-isoxazolepropionate (AMPA) and kainic acid (KA)] or a K(+)channel blocker [4-aminopyridine (4-AP)]. The behavioural changes of such convulsant stimuli on IL-6(-/-) were observed and compared with those observed in C57, IL-6(+/+) and DBA/2 mice. The occurrence of clonic and/or tonic seizures was scored and statistically analysed to observe possible differences on seizure susceptibility. The IL-6(-/-) mice exhibited significantly higher seizure susceptibility to PTZ, beta-CCM, DMCM, NMDA, AMPA and KA than did the other mice strains, with the exception of DBA/2 mice. This study demonstrates that IL-6(-/-) mice possess an increased susceptibility to some convulsant stimuli. In particular, the major convulsant effects produced by NMDA, AMPA and KA suggest that the excitatory amino acid system is more active in the central nervous system (CNS) of IL-6(-/-) mice. The present data suggest that IL-6(-/-) mice might be a valid novel epileptic model for the study of pathophysiology and pharmacology of epileptic seizures.

The two enantiomers of propranolol antagonize generalized tonic-clonic seizures in DBA/2 mice with the (-)-enantiomer being about 1.5 times more potent than the (+)-enantiomer. Metoprolol was less active and atenolol was unable to affect audiogenic seizures. In combination with conventional antiepileptic drugs, both propranolol enantiomers tested in doses not affecting the occurrence of audiogenic seizures increased the anticonvulsant activity of diazepam, phenobarbital, valproate and lamotrigine and tended to increase that of carbamazepine and phenytoin. The effect was more pronounced with the (-)-enantiomer. This increase was associated with an enhancement of motor impairment, however, the therapeutic index of combined treatment of the antiepileptic drugs with both propranolol enantiomers was more favourable than the combination with saline alone. Metoprolol was also able to decrease the ED(50) values of the antiepileptic drugs, whereas atenolol showed no effects. Since neither enantiomer of propranolol significantly influenced the total and free plasma levels of the antiepileptics, pharmacokinetic interactions are not likely. In addition, (+)- and (-)-propranolol did not significantly affect the hypothermic effects of the antiepileptics tested. In conclusion, both enantiomers of propranolol and metoprolol showed an additive anticonvulsant effect when co-administered with some conventional antiepileptic drugs, most notably diazepam, phenobarbital, lamotrigine and valproate, implicating a possible therapeutic relevance of such drug combinations.

Trabectedin (Yondelis(®)) is a potent marine-derived antineoplastic drug with high activity against various soft tissue sarcoma (STS) subtypes as monotherapy, and in combination with pegylated liposomal doxorubicin (PLD) for the treatment of patients with relapsed platinum-sensitive ovarian cancer. This article reviews the safety and pharmacokinetic profiles of trabectedin. Records were identified using predefined search criteria using electronic databases (e.g. PubMed, Cochrane Library Database of Systematic Reviews). Primary peer-reviewed articles published between 1 January 2006 and 1 April 2014 were included. The current safety and tolerability profile of trabectedin, based on the evaluation in clinical trials of patients treated with the recommended treatment regimens for STS and recurrent ovarian cancer, was reviewed. Trabectedin as monotherapy or in combination with PLD, was not associated with cumulative and/or irreversible toxicities, such as cardiac, pulmonary, renal, or oto-toxicities, often observed with other common chemotherapeutic agents. The most common adverse drug reactions (ADRs) were myelosuppression and transient hepatic transaminase increases that were usually not clinically relevant. However, trabectedin administration should be avoided in patients with severe hepatic impairment. Serious and fatal ADRs were likely to be related to pre-existing conditions. Doxorubicin or PLD, carboplatin, gemcitabine, or paclitaxel when administered before trabectedin, did not seem to influence its pharmacokinetics. Cytochrome P450 (CYP) 3A4 has an important role in the metabolism of trabectedin, suggesting a risk of drug-drug interactions with trabectedin used in combination with other CYP3A4 substrates. Trabectedin has a favorable risk/efficacy profile, even during extended treatment in pretreated patients.

Retigabine (D-2319, 0.5-20 mg/kg i.p.) antagonised dose dependently audiogenic seizures in DBA/2 mice. Retigabine at 0.5 mg/kg i.p., a dose that per se did not affect the occurrence of audiogenic seizures significantly, potentiated the anticonvulsant activity of carbamazepine, diazepam, felbamate, lamotrigine, phenytoin, phenobarbital and valproate against sound-induced seizures in DBA/2 mice. The degree of additivity for the effect induced by retigabine was greatest for diazepam, phenobarbital, phenytoin and valproate, less for carbamazepine and lamotrigine and least for felbamate. The increase in anticonvulsant activity was usually associated with a comparable increase in motor impairment. However, the therapeutic index of combined treatment (drugs plus retigabine), was more favourable than the same drug plus vehicle. Since retigabine had no significant influence on the total and free plasma levels of the anticonvulsant drugs, pharmacokinetic interactions, in terms of total or free plasma levels, are not probable. However, the possibility that retigabine modifies the clearance of the anticonvulsant drugs from the brain cannot be excluded. Retigabine had no significant effect on the hypothermic effects of the anticonvulsants tested. In conclusion, retigabine showed an additive effect when administered in combination with classical anticonvulsants, most notably diazepam, phenobarbital, phenytoin and valproate.

We have studied the effects of selective and non-selective adenosine receptor agonists and antagonists in audiogenic-seizure-sensitive DBA/2 mice, an animal model of generalized reflex epilepsy. With the exception of the adenosine A3 receptor agonist, N6-(3-iodobenzyl)-5'-N-methylcarboxamidoadenosine (IB-MECA), all the agonists studied prevented the development of audiogenic seizures in a dose-dependent manner. The ED50 values against the clonic phase of the audiogenic seizures were low, that is: 0.06 mg/kg, i.p., for the adenosine A1 receptor agonist, 2-chloro-N6-cyclopentyladenosine (CCPA), 0.02 and 0.03 mg/kg, i.p., for the adenosine A2A receptor agonists, 2-(4-(2-carboxyethyl)-phenylamino)-5'-N-ethylcarboxamidoadenosine (CGS 21680) and 2-hexynyl-5'-N-ethyl-carboxamidoadenosine (2-HE-NECA), and 0.7 mg/kg, i.p., for the adenosine A1/A3 receptor agonist, N6-2-(4-aminophenyl)ethyladenosine (APNEA). Conversely, the non-selective agonist, N-ethyl-carboxamidoadenosine (NECA), was highly potent, the ED50 being 0.0005 mg/kg, i.p. In the absence of auditory stimulation, the adenosine receptor antagonists increased the incidence of both clonic and tonic seizures in DBA/2 mice. The ED50 values were: for caffeine, 207.5 mg/kg, i.p., for the adenosine A1 receptor antagonist, 8-cyclopentyl-1,3-dipropylxanthine (DPCPX), 327.8 mg/kg i.p., for the adenosine A2A receptor antagonists, 3,7-dimethyl-1-propylxanthine (DPMX), 86.7 mg/kg i.p., for the (E,18%-Z,82%)7-methyl-8-(3,4-dimethoxystyryl)-1,3-dipropylxanthine (KF 17837), 69.1 mg/kg i.p., and 5-amino-7-(2-phenylethyl)-2-(2-furyl)-pyrazolo-(4,3-c)1,2,4-triazolo(1,5 -c)-pyrimidine (SCH 58261), 321.8 mg/kg i.p. The rank order of convulsant potency in our epileptic model, following intracerebroventricular administration, was DPCPX > DMPX > 1,3,7-trimethyl-8-(3-chlorostyryl)xanthine (CSC) > KF 17837 > Caffeine > SCH 58261 > 5-amino-9-chloro-2-(2-furyl)-1,2,4-triazolo(1,5-c)quinazoline (CGS 15943). Following a subconvulsant audiogenic stimulus of 83 dB, all adenosine receptor antagonists induced both tonic and clonic seizures. The ED50 values for such proconvulsant effects were: for caffeine 0.04 mg/kg, i.p., for the adenosine A receptor antagonist, DPCPX, 5.84 mg/kg, i.p., for the adenosine A2A receptor antagonists, DMPX, 0.02 mg/kg, i.p., CGS 15943, 0.29 mg/kg i.p., KF 17837, 0.57 mg/kg, i.p., CSC 0.12 mg/kg, i.p. and SCH 58261 0.07 mg/kg, i.p., respectively. These data suggest that stimulation of adenosine A1 and A2A receptors is involved in the suppression of seizures.

Pharmacovigilance is responsible for monitoring the safety of medicines in normal clinical use and during clinical trials. In the light of the experience acquired and following an assessment by the Commission of the Union system of pharmacovigilance, it has become clear that it is necessary to take measures in order to improve the operation of Union law on the pharmacovigilance of medicinal products for human use. Regulation (EU) No 1235/2010 and Directive 2010/84/EU introduced new legislation on pharmacovigilance. The marketing authorization holder should be responsible for continuously monitoring the safety of its medicinal products for human use, for informing the authorities of any changes that might have an impact on the marketing authorization, and for ensuring that the product information is kept up-to-date. Marketing authorization holders (MAH) record all suspected adverse reactions occurring in the European Union or in the third countries, and which are brought to their attention spontaneously by the patients or their health care, or occurring in the context of post-authorization study. For all medicinal products is mandatory to maintain a pharmacovigilance system master file (PSMF). According to the Legislative Decree 219/2006 the MAH must submit to the competent authorities the information on suspected adverse reactions of a medicinal product, in form of a periodic safety update reports (PSURs).

To assess both clinical and biological efficacy and toxicity of sorafenib in patients with metastatic renal cell carcinoma (mRCC) previously treated with an anti-angiogenic vascular endothelial growth factor receptor (VEGFR) tyrosine kinase inhibitor.Sorafenib is an orally active multikinase inhibitor approved for the treatment of mRCC. Drug-focused translational research on tissues (i.e. B-RAF) and plasma (VEGFR-α, circulating endothelial cells, endothelial progenitor cells) was performed to define biological predictive and prognostic markers and their related kinetics. Patients with mRCC pretreated with an anti-angiogenic treatment, an Eastern Cooperative Oncology Group performance status (ECOG PS) of 0-2 and adequate organ function were eligible. Patients received sorafenib 400 mg twice a day continuously in 4-week cycles. Patients with no progressive disease at 12 weeks continued to receive sorafenib at the standard dose, whereas progressing patients received an increased dose (600 mg twice a day) with early disease restaging after 4 weeks. Patients who progressed at 600 mg twice a day went off study. Efficacy (overall tumour control) was assessed by Response Evaluation Criteria in Solid Tumors.In all, 19 patients were entered. The baseline characteristics were as follows: ECOG PS 0-1 94.8%; median (range) age 62 (41-81) years; nephrectomy 100%; surgery for metastatic disease 26.4%; clear cell 79.1%; papillary cell 15.7%; sarcomatoid/high grade 5.2%; two or more metastatic sites 84%. Overall, 11 patients (58%) had disease control at 6 months without significant correlation between response to prior therapy and hypertension. Progression-free survival (PFS) of 8.3 months was observed. Of six patients for whom the dose was escalated due to early progression, three benefitted with PFS of3 months. Three (15.7%) of 19 patients had a V600E mutation and one had a K601E mutation; PFS appeared to be substantially shorter in these patients compared with 15 patients with wild-type B-RAF (2.5 vs 9.1 month, P0.05). The most common toxicity (National Cancer Institute Common Toxicity Criteria, NCIC 3.0, all patients) was grade ≥1 diarrhoea and grade 2-3 hand-foot syndrome in 11 patients. Grade 3 mucositis was observed in one patient.Sorafenib at doses of 400-600 mg twice a day continuously results in acceptable and well tolerated salvage treatment after VEGFR tyrosine kinase inhibitor failure. In progressive patients, treatment with a higher dose could be a valid option and B-RAF mutations may be an interesting predictive marker to be studied in a larger randomized trial.

The renin-angiotensin system (RAS) exists in the brain and it may be involved in pathogenesis of neurological and psychiatric disorders including seizures. The aim of the present research was to evaluate the effects of some angiotensin-converting enzyme inhibitors (ACEi; captopril, enalapril, fosinopril and zofenopril), commonly used as antihypertensive agents, in the DBA/2 mice animal model of generalized tonic-clonic seizures. Furthermore, the co-administration of these compounds with some antiepileptic drugs (AEDs; carbamazepine, diazepam, felbamate, gabapentin, lamotrigine, phenobarbital, phenytoin, topiramate and valproate) was studied in order to identify possible positive interactions in the same model. All ACEi were able to decrease the severity of audiogenic seizures with the exception of enalapril up to the dose of 100mg/kg, the rank order of activity was as follows: fosinopril>zofenopril>captopril. The co-administration of ineffective doses of all ACE inhibitors with AEDs, generally increased the potency of the latter. Fosinopril was the most active in potentiating the activity of AEDs and the combination of ACEi with lamotrigine and valproate was the most favorable, whereas, the co-administrations with diazepam and phenobarbital seemed to be neutral. The increase in potency was generally associated with an enhancement of motor impairment, however, the therapeutic index of combined treatment of AEDs with ACEi was predominantly more favorable than control. ACEi administration did not influence plasma and brain concentrations of the AEDs studied excluding pharmacokinetic interactions and concluding that it is of pharmacodynamic nature. In conclusion, fosinopril, zofenopril, enalapril and captopril showed an additive anticonvulsant effect when co-administered with some AEDs, most notably carbamazepine, felbamate, lamotrigine, topiramate and valproate, implicating a possible therapeutic relevance of such drug combinations.

Summary Background Gastrointestinal stromal tumours (GISTs) are rare tumours of the gastrointestinal tract characterised by cell-surface expression of the tyrosine kinase KIT (CD117). No effective systemic treatment is available. Imatinib (STI571) inhibits a similar tyrosine kinase, BCR-ABL, leading to responses in chronic myeloid leukaemia, and has also been shown to inhibit KIT. We did a phase I study to identify the dose-limiting toxic effects of imatinib in patients with advanced soft tissue sarcomas including GISTs. Methods 40 patients (of whom 36 had GISTs) received imatinib at doses of 400 mg once daily, 300 mg twice daily, 400 mg twice daily, or 500 mg twice daily. Toxic effects and haematological, biochemical, and radiological measurements were assessed during 8 weeks of follow-up. 18 Fluorodeoxy-glucose positron-emission tomography (PET) was used for response assessment in one centre. Findings Five patients on 500 mg imatinib twice daily had dose-limiting toxic effects (severe nausea, vomiting, oedema, or rash). Inhibition of tumour growth was seen in all but four patients with GISTs, resulting in 19 confirmed partial responses and six as yet unconfirmed partial responses or more than 20% regressions. 24 of 27 clinically symptomatic patients showed improvement, and 29 of 36 were still on treatment after more than 9 months. PET scan responses predicted subsequent computed tomography responses. Interpretation Imatinib at a dose of 400 mg twice daily is well tolerated during the first 8 weeks, side-effects diminish with continuing treatment, and it has significant activity in patients with advanced GISTs. Our results provide evidence of a role for KIT in GISTs, and show the potential for the development of anticancer drugs based on specific molecular abnormalities present in cancers.

In the present study, we provide evidences for a differential effect of perinatal alcohol exposure with a direct correlation to the genetic background on the development of seizures. Ethanol (EtOH) is a widely used psychoactive substance that exerts its action by affecting multiple targets in the central nervous system. EtOH is known to interact with almost all identified neurotransmitters although its effects on excitatory and inhibitory amino acid neurotransmissions are considered to be particularly important in the mediation of its behavioural effects. Prenatal exposure to alcohol is associated with a wide variety of offspring's abnormalities which lead to the so called foetal alcohol syndrome (FAS), which is also related to a higher susceptibility to convulsions. In our study, a rat strain of convulsive epilepsy, the GEPRs rats, displayed an increase of seizure susceptibility after foetal exposure to this teratogenic drug, while a non-convulsive rat strain of absence epilepsy, the WAG/Rij rat, did not fully develop its characteristic features. However, when all groups of rat where tested for pentyletetrazole-induced convulsion, animals perinatally treated with ethanol were less responsive in comparison to their respective controls. These results are in agreement with previous reports showing how the genetic background can directly influence the teratogenic effects of alcohol, and this can be strictly related to the variability in the observation of offspring anomalies in humans which has lead to a 5-category classification system for individuals exposed to alcohol in uterus.

Levetiracetam (LEV, [S]-alpha-ethyl-2-oxo-1-pyrrolidine acetamide) is a new antiepileptic that has been used as adjunctive therapy to treat patients with intractable epilepsy. Systemic administration of levetiracetam (2.5-30 mg/kg, intraperitoneally (i.p.)) was able to produce a dose-dependent decrease in DBA/2 audiogenic seizure severity score. In combination with conventional antiepileptic drugs, levetiracetam, 5mg/kg, i.p., which per se did not significantly affect the occurrence of audiogenic seizures in DBA/2 mice, potentiated the anticonvulsant activity of some antiepileptic drugs studied against sound-induced seizures in DBA/2 mice. The degree of potentiation induced by levetiracetam was greater, approximately twice, for carbamazepine, diazepam, felbamate, topiramate, gabapentin, and valproate, less for lamotrigine, phenobarbital and phenytoin. This increase was associated with a comparable impairment in motor activity; however, the therapeutic index of combined treatment of antiepileptic drugs with levetiracetam was more favourable than the combination with saline with the exception of lamotrigine, phenytoin and phenobarbital. Since levetiracetam did not significantly influence the total and free plasma and the brain levels of antiepileptics studied. In addition, levetiracetam did not significantly affect the hypothermic effects of the anticonvulsants tested. In conclusion, levetiracetam showed an additive anticonvulsant effect when administered in combination with some classical anticonvulsants, most notably carbamazepine, diazepam, felbamate, gabapentin, topiramate and valproate, implicating a possible therapeutic relevance of such drug combinations.

Genetic animal models have contributed significantly to our understanding of epilepsy causes. Lethargic mice are considered a valid model of absence epilepsy, which have been shown to possess behavioral, electrographic and pharmacological profiles similar to those of humans with absence epilepsies. Single gene mutations that comprise the β 4 subunit of voltage-sensitive Ca 2+ channels underlie the spontaneous discharges of the absence, non-convulsive seizures of lethargic mice. There are no available data concerning how the mutant channels actually behave at terminals in response to chemical activation by subconvulsant stimulation with pentylenetetrazole. In this study, we found no significant difference in the convulsive dose 50 between lethargic and control mice. Lethargic mice showed a more rapid development of kindling to pentylenetetrazole than control animals. No significant differences were observed between the groups of mice rechallenged with pentylenetetrazole 30 or 60 days after the end of the chronic treatment. Marked differences in brain amino acid levels were found between the two strains of mice in basal conditions and after kindling. In conclusion, our results indicate that lethargic mice show a range of biochemical and behavioral changes, correlated in particular with a higher susceptibility to develop kindled seizures.

Carbenoxolone, the succinyl ester of glycyrrhetinic acid, is an inhibitor of 11beta-hydroxy steroid dehydrogenase and gap junctional intercellular communication. It is currently used in clinical treatment of ulcer diseases. Systemic administration of carbenoxolone (1-40 mg/kg, intraperitoneally (i.p.)) was able to produce a dose-dependent decrease in DBA/2 audiogenic seizure severity score. Glycyrrhizin, an analogue of carbenoxolone inactive at the gap-junction level, was unable to affect audiogenic seizures at doses up to 30 mg/kg. In combination with conventional antiepileptic drugs, carbenoxolone, 0.5 mg/kg, i.p., which per se did not significantly affect the occurrence of audiogenic seizures in DBA/2 mice, potentiated the anticonvulsant activity of carbamazepine, diazepam, felbamate, gabapentin, lamotrigine, phenytoin, phenobarbital and valproate against sound-induced seizures in DBA/2 mice. This effect was not observed after the combination of glycyrrhizin (10 mg/kg, i.p.) with some conventional antiepileptic drugs. The degree of potentiation induced by carbenoxolone was greater for diazepam, felbamate, gabapentin, phenobarbital and valproate, less for lamotrigine, phenytoin and carbamazepine. This increase was associated with a comparable impairment in motor activity; however, the therapeutic index of combined treatment of antiepileptic drugs with carbenoxolone was more favourable than the combination with glycyrrhizin or saline. Since carbenoxolone did not significantly influence the total and free plasma levels of diazepam, felbamate, gabapentin, lamotrigine, phenytoin, phenobarbital, valproate and carbamazepine, pharmacokinetic interactions are not likely. However, the possibility that carbenoxolone can modify the brain clearance of the anticonvulsant drugs studied may not be excluded. In addition, carbenoxolone did not significantly affect the hypothermic effects of the anticonvulsants tested. In conclusion, carbenoxolone showed an additive anticonvulsant effect when administered in combination with some classical anticonvulsants, most notably diazepam, felbamate, gabapentin, phenobarbital, and valproate, implicating a possible therapeutic relevance of such drug combinations.

In a phase I study conducted by the EORTC Soft Tissue and Bone Sarcoma Group, 40 patients with advanced soft tissue sarcomas, most of whom had gastrointestinal stromal tumors (GISTs), received imatinib at doses of 400 mg q.d., 300 mg b.i.d., 400 mg b.i.d., or 500 mg b.i.d. Dose-limiting toxicities, including severe nausea, vomiting, edema and rash, were seen at the highest dose level; the maximum tolerated dose was therefore 400 mg b.i.d. Imatinib was active in the group of 35 patients with GISTs, producing partial responses in 19 (54%) patients and stable disease in 13 patients (37%). Responding patients have now been followed for a minimum of 10 months. The most common side effects seen in patients continuing on therapy have been periorbital edema (40%), peripheral edema (37.5%), fatigue (30%), skin rash (30%) and nausea/vomiting (25%). Severe late myelosuppression has also been seen occasionally. Eighteen (51%) GIST patients continue to have partial responses and 11 (31%) continue with stable disease. Thus, 82% of patients with GISTs are still obtaining clinically important benefits with continued imatinib therapy. Some patients showed accelerated progressive disease shortly after starting imatinib. On the other hand, following drug withdrawal, 2 patients had reductions in tumor burden and remain alive without drug therapy. In summary, imatinib is generally well tolerated and has significant activity during long-term treatment of patients with advanced GISTs.

The non-selective alpha-amino-3-hydroxy-5-methyl-isoxazole-4-propionic acid (AMPA) receptor antagonists, 2,3-benzodiazepine derivatives CFM-1 (3,5-dihydro-7,8-dimethoxy-1-phenyl-4H-2,3-benzodiazepin-4-one) and CFM-2 (1-(4'-aminophenyl)-3,5-dihydro-7,8-dimethoxy-4H-2,3-benzodiazepin -4-one), following intraperitoneal (i.p.) administration, were studied against audiogenic seizures in genetically epilepsy-prone rats (GEPRs) or pentylenetetrazole induced kindling in rats. After acute i.p. administration the ED50 values of CFM-1 against the clonic and tonic phases of the audiogenic seizures 30 min after pretreatment were 40 (16-100) and 13 (8-25) micromol kg(-1), respectively. The animals used for chronic study were treated i.p. daily (at 10 h) for 4 weeks with CFM-1 (20 or 50 micromol kg(-1)). Chronic treatment for 2 weeks with CFM-1 gave ED50 values against clonic and tonic seizures of 39 (22-69) and 16 (8-25) micromol kg(-1), respectively, whereas chronic treatment for 4 weeks gave ED50 values against clonic and tonic seizures of 42 (18-98) and 17 (7-41.3) micromol kg(-1), respectively. The duration of anticonvulsant activity observed between 0.5 and 4 h following administration of CFM-1 was similar for acute and chronic treatment. Two groups of Sprague-Dawley rats received CMF (20 or 50 micromol kg(-1)) 30 min before a subconvulsant dose of pentylentetrazole (25 mg kg(-1) i.p.) which is able to increase seizure severity in control animals (i.e., chemical kindling). Pretreatment with CFM-2 delayed the progression of seizure rank during repeated administration of pentylentetrazole. At the end of the period of repeated pentylentetrazole treatment (6 weeks) the mean seizure score was 0 in vehicle treated controls, 4.3 in animals treated with vehicle + pentylentetrazole, 2.2 in rats treated chronically with CFM-2 (20 micromol kg(-1) i.p.) + pentylentetrazole and 1.0 in rats treated repeatedly with CFM-2 (50 micromol kg(-1) i.p.) + pentylenetetrazole. CFM-2 was also able to antagonize the long-term increase in sensitivity of the convulsant effects of GABA function inhibitors in pentylentetrazole-kindled animals. Thus, the administration of a challenge dose of pentylentetrazole (15 mg kg(-1) i.p.) or picrotoxin (1.5 mg kg(-1) i.p.) 15 or 30 days after the end of the repeated treatment showed that animals treated with CFM-2 were significantly protected against seizures induced by pentylentetrazole or picrotoxin. The data suggest that, following repeated treatment, tolerance to the novel AMPA receptor antagonists does not develop (CFM-1 in genetically epilepsy-prone rats and CFM-2 in the pentylentetrazole kindling model of epilepsy). Thirteen minutes after drug injection on days 1, 14 and 28 of chronic treatment the motor impairment induced by these compounds was studied with a rotarod apparatus. The TD50 values for CFM-1 or CFM-2-induced impairment of locomotor performance were similar following acute and repeated treatment. The data also suggest that some novel 2,3-benzodiazepines may have clinical potential for some types of epilepsy.

1. 1. In addition to binding to GABA A receptors in the central nervous system, benzodiazepines have also been reported to recognize high affinity binding sites in several different peripheral tissues. 2. 2. These peripheral benzodiazepine receptors likely consist of distinct integral membrane proteins, which are predominantly localized in the outer mitochondrial membrane and may be associated to form a heteropolymeric receptor complex. One such protein, identified for its ability to bind a class of benzodiazepines and isoquinolines, has been purified and the corresponding complementary DNA (cDNA) has been cloned and characterized. Furthermore, the structure of the rat gene encoding this protein has been clarified, thus potentially opening new insights into the molecular mechanisms responsible for receptor regulation. 3. 3. Although the exact physiologic and/or pharmacologic role of peripheral benzodiazepine receptors is still unknown, their wide tissue distribution suggests an involvement in many cellular phenomena. 4. 4. In particular, several lines of investigation indicate that these receptors, densely expressed on airway smooth muscle of various species, may contribute to the modulation of bronchomotor tone and perhaps to the pathogenesis of asthma and airway hyperresponsiveness.

The effects of repeated administration of the selective adenosine A 1 receptor agonist 2-chloro- N 6 -cyclopentyladenosine (CCPA), the selective adenosine A 2 receptor agonist 2-hexynyl-5′- N -ethylcarboxamidoadenosine (2HE-NECA), the non-selective adenosine A 1 /A 2 receptor agonist 5′- N -ethylcarboxamidoadenosine (NECA), the selective adenosine A 1 receptor antagonist 8-cyclopentyl-1,3 dipropylxanthine (DPCPX) and the selective adenosine A 2 receptor antagonist 5-amino-7-(2-phenylethyl)-2-(2-furyl)-pyrazolo-(4,3-e)1,2,4-triazolo(1,5-c)pyrimidine (SCH 58261) on the anticonvulsant activity of 3-(2-carboxypiperazine-4y)propenyl-1-phosphonic acid (CPPene), a selective N -methyl- d -aspartate receptor antagonist, were evaluated in audiogenic sensible dilute brown agouti mice DBA/2J (DBA/2). Mice were treated intraperitoneally twice daily for 7 days with CCPA 0.11 mg/kg, 2HE-NECA 0.056 mg/kg, NECA 0.11 mg/kg, DPCPX 0.5 mg/kg and SCH 58261 0.5 mg/kg followed by 2 vehicle injections (the wash-out period of 1 day) and subsequently CPPene was administered intracerebroventricularly. Audiogenic seizures were delivered 30 min after CPPene administration. Repeated treatment with CCPA significantly reduced the anticonvulsant properties of CPPene against audiogenic seizures. A weak and not significant reduction of anticonvulsant effects of CPPene was observed following repeated administration of NECA, whilst the repeated administration of 2HE-NECA did not decrease the antiseizure activity of CPPene. Conversely, repeated administration of DPCPX markedly potentiated the anticonvulsant properties of CPPene, whilst the repeated treatment with SCH 58261 did not increase the anticonvulsant activity of CPPene. The present results indicate that repeated treatment with CPPA, a selective adenosine A 1 receptor agonist, decreases the anticonvulsant properties of CPPene, whilst the repeated administration of DPCPX, a selective adenosine A 1 receptor antagonist, potentiates the anticonvulsant effects of CPPene. The compounds acting as selective agonists or antagonists of adenosine A 2 receptors do not affect the antiseizure activity of CPPene. In conclusion, the repeated interaction of agonists or antagonists with adenosine A 1 receptors seems to induce changes on anticonvulsant activity of CPPene, whereas drugs acting at adenosine A 2 receptors do not.

The development of tolerance to the anticonvulsant effects of clonazepam, clobazam, and diazepam were studied in genetically epilepsy-prone rats following intraperitoneal (IP) or oral administration. The anticonvulsant effects were evaluated on seizures evoked by means of auditory stimulation (109 dB, 12-16 kHz). All compounds showed 60 min after IP injection antiseizure activity with ED50 against clonus of 0.24 mumol kg-1 for clonazepam, 0.72 mumol kg-1 for diazepam, and 3.9 mumol kg-1 for clobazam. After 120 min of oral administration the ED50 against clonus of 2.37 mumol kg-1 for clonazepam, 15.8 mumol kg-1 for diazepam, and 30 mumol kg-1 for clobazam. The dose chosen for the chronic treatment were 2.5 mumol kg-1 for clonazepam, 15 mumol kg-1 for diazepam, and 30 mumol kg-1 for clobazam. The animals were treated three times daily for 4 or 6 weeks. Auditory stimulation was administered 60 min after drug IP injection on various days. During treatment, tolerance was observed as a loss of drug anticonvulsant effects. No changes of occurrence of audiogenic seizures was observed in rats treated with vehicle. Tolerance to the anticonvulsant activity developed most rapidly during clobazam treatment, less rapidly following diazepam treatment, and most slowly during clonazepam treatment. Sixty minutes after IP injection on various days of chronic treatment the motor impairment induced by these benzodiazepines was also studied by means of a rotarod apparatus. The tolerance to the motor impairment developed more rapidly than the anticonvulsant effects. The response to auditory stimulation to benzodiazepines was stopped 24 and 48 h after chronic treatment with these compounds, showing no residual drug effects and that rats were still tolerant. The genetically epilepsy-prone rats is a reliable and sensitive model for studying long-term effects of anticonvulsant drugs.

Chronic administration of propionyl-l-carnitine has been recently shown to correct hypertrophy related abnormalities in muscle mechanics. Accordingly, this study investigated whether the drug would similarly improve cardiac dynamics in rats with pressure overload. Enalapril was used for comparison. Drugs were administered in the drinking water for 3 weeks to Wistar Kyoto rats with a 2 week abdominal aortic constriction. Cardiac function was studied under urethane anaesthesia in basal conditions, during increase in preload, and during increase in afterload. Basal cardiac function was comparable in pressure-overloaded and sham-operated animals. Neither propionyl-l-carnitine nor enalapril affected the basal performance. Compared to sham-operated animals, untreated pressure-overloaded rats showed an impaired cardiac response (cardiac output, stroke volume) to preload increase induced by saline i.v. infusion. Propionyl-l-carnitine dose dependently improved cardiac function in the range 30-180 mg/kg, without affecting cardiac hypertrophic growth. Enalapril (3 mg/kg) reduced cardiac hypertrophy and improved cardiac function. The two effects were unrelated. The afterload increase by total aortic occlusion evidenced a reduction in the left ventricle pressure generating capacity of hypertrophied hearts. Propionyl-l-carnitine did not modify this parameter, while enalapril afforded a significant improvement. Results show that propionyl-l-carnitine significantly improves in vivo cardiac dynamics under conditions of increased energy demand. The effect is not due to inotropic efficacy, but presumably to increased cardiac efficiency.

Microinjection of N-methyl-D-aspartate (NMDA; 1 and 2.5 nmol) or kainate (KA; 50 pmol) into the deep prepiriform cortex elicited behavioral signs of seizure activity. No epileptiform activity was observed after deep prepiriform cortex microinjection of either L-arginine (L-Arg, 5 and 10 nmol) or its D-enantiomer, D-arginine (D-Arg, 2.5-10 nmol). However, both the seizure score and the incidence of electroencephalographic (EEG) epileptic discharges elicited by NMDA (1 and 2.5 nmol) and KA (50 pmol) were significantly increased by L- but not D-Arg. The facilitatory effects of L-Arg on seizure activity elicited by both NMDA and KA were dose-dependent and could be prevented by co-administration of L-Arg (10 nmol) and the nitric oxide (NO) synthase inhibitor, N omega-nitro-L-arginine methyl ester (L-NAME, 20 nmol). Motor and electrocortical seizures were observed after microinjection of the NO donor sodium nitroprusside (SNP; 5 to 20 nmol) into the deep prepiriform cortex. Infusion of methylene blue (20 nmol), a soluble guanylate cyclase inhibitor, protected against SNP-induced seizures. Furthermore, prior infusion of a subconvulsant dose of SNP into the deep prepiriform cortex significantly potentiated the seizure activity elicited by either NMDA (1 and 2.5 nmol) or KA (50 pmol). These results support the proposal that NO is formed from L-Arg upon excitatory amino acid receptor activation within the deep prepiriform cortex, thereby contributing to the genesis of seizure activity.

1. 1. The convulsant activity of the calcium voltage L-channel agonist Bay k 8644 was studied in genetically epilepsy prone DBA/2 mice. 2. 2. Seizures were induced by intracerebroventricular injection of Bay k 8644. 3. 3. These seizures were reversed by some calcium channel blockers such as dihydropyridines, some excitatory amino acid antagonists such as 2-amino-7-phosphonoeptanoate and CPPene, 2-chloroadenosine, some anticonvulsant drugs such as magnesium valproate, diazepam and clonazepam and two kappa opioid agonists (U-50488H and U-54494A). 4. 4. The remaining antiepileptic drugs (carbamazepine, phenytoin, phenobarbital and trimethadione) were ineffective in this respect. Other anticonvulsant compounds such as dizocilpine (MK 801), ketamine and drugs enhancing GABAergic transmission did not significantly affect the clonic phase of the seizures induced by Bay k 8644. 5. 5. These results show that Bay k 8644 seizures are relatively resistant to some anticonvulsant compounds. The role of some neurotransmitters on seizures induced by Bay k 8644 is discussed.