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Renal function deterioration is a rather frequent side effect of ticagrelor; this is especially so in patients over the age of 75, with pre-existent mild renal failure and/or taking an angiotensin receptor inhibitor. We describe a patient in whom deterioration of renal function due to ticagrelor led to a rise in serum concentration of rosuvastatin which resulted in rhabdomyolysis. The presented case emphasises the importance to check renal function routinely before and one month after starting ticagrelor and to screen carefully for possible interactions with other drugs.

Objective: To determine long-term retention, percentage of patients withdrawing because of adverse events, percentage of patients achieving seizure freedom, safety profile of the new anti-epileptic drugs lamotrigine, levetiracetam and topiramate., Methods: All patients treated with lamotrigine, levetiracetam or topiramate in the Epilepsy Centre were identified. Each drug was analyzed from introduction of the drug in the Netherlands up to a final assessment point 2 years later., Results: Data from 1066 patients were included: 336 for lamotrigine, 301 for levetiracetam, 429 for topiramate. Two-year retention rates were 69.2% (lamotrigine), 45.8% (levetiracetam), 38.3% (topiramate); (LTG vs. LEV at p<0.001; LTG vs. TPM at p<0.001; LEV vs. TPM at p=0.005). Seizure freedom rates were lowest for lamotrigine and highest for levetiracetam. Adverse events played a role in drug discontinuation in 154/429 patients (35.9%) on topiramate, 52/336 patients (15.5%) on lamotrigine (p<0.001), 68/301 patients (22.5%) on levetiracetam (p<0.001). Mood and general CNS-effects are common in patients on lamotrigine and levetiracetam, and neurocognitive side effects are most prevalent in patients on topiramate. A positive effect on cognition is frequently noted in patients on lamotrigine., Conclusion: A drug that is only modestly efficacious but has a favourable safety profile may look better than a drug that is more efficacious but produces clinically meaningful adverse events. Therefore, a drug's retention rate is mainly determined by its side effect profile. As a consequence, retention rate was highest for lamotrigine and lowest for topiramate. Intermediate retention rates were seen with levetiracetam use.

Lamotrigine (LTG, Lamictal), one of the newer antiepileptic drugs, was admitted to the Dutch market in 1996. It was first used as adjunctive therapy and later as a monotherapy in partial and generalized epilepsy. All patients who started on LTG in 1996 or 1997 in the Epilepsy Centre Kempenhaeghe (n=314) were enrolled in this study and followed for 48 months. The data indicate that the retention rates for LTG after 1, 2, 3, and 4 years are respectively 74.4, 69.3, 63.1, and 55.6%. Patients with normal cognitive function were more likely to continue than patients with mental retardation. The main reason for discontinuing LTG therapy was lack of efficacy (19.1%). Four patients (1.4%) were seizure-free for the total follow-up period of 48 months. The most frequently reported negative side effects were dizziness and headache, both in patients who continued and in those who discontinued therapy. A large percentage of patients also reported positive side effects like "feeling/being more active" and "feeling more clear/more responsive." For the whole patient group, the plasma level of LTG was measured 277 times. Plasma levels of LTG were influenced by the patients' comedications. Plasma levels of LTG in groups taking LTG in monotherapy, LTG plus an inducer, and LTG plus valproate were 8.7, 4.8, and 8.7 mg/L, respectively. The correlation between measured plasma level and dose confirm the manufacturer's dose recommendations. The manufacturer recommends half the dosage of lamotrigine monotherapy when the patient also uses valproate. When the patient uses an inducer, the dosage of LTG must be two times the dose used in monotherapy.

Objective: Two of the most commonly prescribed new antiepileptic drugs as add-on therapy for patients with chronic refractory epilepsies are topiramate and levetiracetam. In regulatory trials, both drugs were characterized as very promising new antiepileptic drugs. However, results from these highly controlled short-term clinical trials cannot simply be extrapolated to everyday clinical practice, also because head-to-head comparisons are lacking. Therefore, results from long-term open label observational studies that compare two or more new AEDs are crucial to determine the long-term performance of competing new antiepileptic drugs in clinical practice., Method: We analyzed all patients referred to a tertiary epilepsy centre who had been treated with topiramate from the introduction of the drug in spring 1993 up to a final assessment point mid-2002 and all patients who had been treated with LEV in the same centre from the introduction of the drug in early 2001 up to a final assessment point end-2003 using a medical information system., Results: Three hundred and one patients were included for levetiracetam and 429 patients for TPM. Retention rate after 1 year was 65.6% for LEV-treated patients and 51.7% for TPM-treated patients (p=0.0015). Similarly, retention rates for LEV were higher at the 24-month mark: 45.8% of LEV-treated patients and 38.3% of TPM-treated patients were still continuing treatment (p=0.0046). Adverse events led to drug discontinuation in 21.9% of TPM-treated patients compared to 6.0% of LEV-treated patients (p<0.001). The number of patients discontinuing treatment because of lack of efficacy was similar for both groups. Seizure freedom rates varied between 11.6 and 20.0% for TPM and between 11.1 and 14.3% for LEV per 6-months interval. Several important AED specific adverse events leading to drug discontinuation were identified, including neurocognitive side effects from TPM and mood disorders from LEV., Conclusion: The retention rate for LEV is significantly higher than for TPM. LEV had a more favourable side effect profile than TPM with comparable efficacy. Patients on TPM discontinued treatment mainly because of neurocognitive side effects. In the treatment with LEV, the effects on mood must not be underestimated.

Objective: For the treatment of patients with chronic refractory epilepsies, development of new antiepileptic drugs is crucial. Three regulatory trials have demonstrated that add-on levetiracetam is efficacious in patients with localization-related epilepsy. However, results from these highly controlled short-term clinical trials cannot simply be extrapolated to everyday clinical practice. Therefore, more information is needed about the long-term profile of a new antiepileptic drug in clinical practice., Method: We analyzed all patients who had been treated with levetiracetam in the Epilepsy Centre Kempenhaeghe from the introduction of the drug in early 2001 up to a final assessment point, at the end of 2003, using a medical information system., Results: In total, 301 patients were included. One hundred thirty-eight patients (45.8%) discontinued LEV treatment during the 24-month follow-up period. Reasons for discontinuation were lack of efficacy in 15.9% of patients, adverse events in 6.0% of patients, and a combination of lack of efficacy and adverse events in 16.3% of patients. By Kaplan-Meier survival analysis, the continuation rate was 65.6% after 1 year and 45.8% after 2 years. About 15% of patients in this highly refractory group had a 3-month remission, whereas 10% of patients became seizure-free for longer periods. The most frequently reported side effects at the time of discontinuation were mood disorders, tiredness, and sleepiness. Variables predicting (dis)continuation of levetiracetam treatment could not be identified., Conclusion: Levetiracetam is a new antiepileptic drug that appears to be a useful add-on treatment in patients with refractory epilepsy. Its side effect profile is mild, with mood disorders being the most dominant adverse event.

Introduction: Neurocognitive complaints may interfere with long-term antiepileptic drug (AED) treatment and are an important issue in clinical practice. Most data about drug-induced cognitive problems are derived from highly controlled short-term clinical trials. We analyzed such cognitive complaints for the two most commonly used AEDs in a clinical setting using patient perceived problems as primary outcome measure., Method: All patients of the epilepsy center Kempenhaeghe that received topiramate (TPM) or levetiracetam (LEV) from the introduction to mid 2004 were analyzed using a medical information system, an automated medical file. Patients were analyzed after 6, 12, and 18 months of treatment., Results: Four hundred and two patients used either TPM (n = 260) or LEV (n = 142); 18 months retention showed a statistically significant difference, revealing 15% more patients that continued LEV compared to TPM: 18 months retention 46% for TPM and 61% for LEV [F (1.400) = 3.313, p = 0.043]. Neurocognitive complaints accounted for a significant number of drug discontinuations and especially the high frequency of neurocognitive complaints in the first period of TPM treatment appeared to be significant different from LEV [F(2,547) = 3.192, p = 0.042]. In the remaining patients, the difference in neurocognitive complaints was not statistically significant., Conclusion: cognitive complaints are common in TPM treatment and frequently lead to drug withdrawal. The impact of LEV on cognitive function is only mild. This leads to a much higher (15%) drug discontinuation rate for TPM compared to LEV.

Mood-modulating profiles of antiepileptic drugs (AEDs) have been classified by Ketter, Post, and Theodore [Neurology 1999; 53 (5, Suppl. 2) S53-76] into two classes: the first class is assumed to have deactivating effects related to GABA potentiation, and the second class is assumed to have activating effects that are associated with glutamate attenuation. We tested this hypothesis by reviewing the multiple mechanisms of action of topiramate (TPM) and levetiracetam (LEV) together with clinical behavioral side effects of patients who had been treated with TPM and LEV in a tertiary referral center for epilepsy. We found LEV to manifest activating and deactivating side effects equally and TPM to act as a deactivating AED, with tiredness/sleepiness side effects being predominant. TPM, in comparison to LEV, was found to be associated with a high incidence of side effects. Testing the hypothesis of Ketter et al. (1999) the deactivating effects of TPM may be coupled to a predominance of potentiation of GABA, but the oversimplified basis of the model needs to be acknowledged.

For the treatment of patients with chronic refractory epilepsies, information about the long-term efficacy and safety profile of any new antiepileptic drug is crucial. Topiramate has been proven to be effective in patients with refractory chronic partial epilepsies in short-term controlled clinical trials, but the long-term retention, long-term efficacy, and long-term side-effect profile have not been sufficiently investigated. We analyzed all patients who had been treated with topiramate in the Epilepsy Centre Kempenhaeghe from the introduction of the drug in the spring of 1993 up to a final assessment point in mid-2002. In total, 470 patients were identified. The data show that the clinical dose achieved was about 200mg/day, reached after approximately 6 months of treatment. Further dose escalation in the survivors was slow, with a mean dose of about 300 mg/day after 24 months of treatment. Mean titration dose is 25mg/week, but titration strategy is mostly individual and responds to patient complaints. With respect to seizure frequency, 10-15% of the patients were seizure-free at the 6-month evaluation; 4 patients achieved a 2-year remission. Retention rate was 53% after 1 year, 45% after 2 years, 38% after 3 years, and 30% after 4 years. At 4 years, almost 70% of the patients had discontinued topiramate. The main reason was adverse events, which accounted for about 65% of the discontinuations. Behavioral side effects were dominant, with mental slowing (27.6%), dysphasia (16.0%), and mood problems (agitation: 11.9%) being the most frequently reported side effects. In about 10% of the patients side effects led to discontinuation despite the obvious favorable effects on seizure frequency. Comparisons between the patients who discontinued topiramate treatment and those who continued topiramate showed that discontinuation was associated with comedication (vigabatrin and lamotrigine). Our conclusion is that TPM is associated with a high incidence of side effects in clinical practice, affecting long-term retention. Meaningful prognostic factors that may help us in clinical decision making, i.e., to prevent the side effects or to help us identify those at risk, have not been found.

Purpose: This study aimed at investigating the cognitive and mood effects of lamotrigine (LTG) versus valproate (VPA) and placebo (PBO)., Methods: By studying the effects in healthy volunteers, it is possible to separate the genuine effects of LTG from the cognitive improvements, caused by better seizure control. The study used a pretest-posttest comparison of 50 mg LTG, 900 mg VPA, or PBO in a double-blind single-dummy parallel-group design with 30 healthy volunteers. Study duration was 12 days (with a last control on day 13). Outcome measures included cognitive tests (FePsy neuropsychological test battery), mood scales (ASL; mood-rating scale), and a scale for subjective complaints (ABNAS Neurotoxicity scale). Total sleep time was controlled with actigraphic recordings. The results were analyzed by comparing the change over time (pretest with posttest) for the three treatments with Student's t tests., Results: COGNITIVE TESTS: significant differences between the treatments were found for measurements of cognitive activation (i.e., three of the four simple reaction-time measurements showed statistically significant differences in change between PBO and LTG in favor of LTG (p=0.03; 0.03; 0.04); two of four tests showed statistically significant differences in change between LTG and VPA, both in favor of LTG (p=0.03; 0.05). SUBJECTIVE COMPLAINTS: the ABNAS-neurotoxicity scale reveals a significant reduction of drug-related cognitive complaints for the subjects taking LTG, relative to VPA (p=0.02). MOOD RATING: significant changes were found on the scale assessing "tiredness," showing increased tiredness/sedation for VPA relative to PBO (p=0.02) and on the "timid scale" for LTG reporting "being more at ease" compared with both PBO and VPA (p=0.02; 0.02). The general direction of change for the mood scales was toward "activation" for LTG (five of six scales improved), whereas for VPA, the reverse effect was found (four of six scales showed a change in the direction of "tiredness/sedation")., Conclusions: Short-term treatment in normal volunteers with a low dose of LTG resulted in improved cognitive activation on simple reaction-time measurements, a more positive subjective report about the impact of drug treatment relative to VPA, and mood changes concurring with the activating effect demonstrated by the cognitive tests.

The efficacy of feverfew capsules on migraine prophylaxis was investigated in a randomized double-blind, placebo-controlled crossover study in which 50 patients, who had not used feverfew before, participated. The capsules were filled with a dried alcoholic extract of feverfew on microcristalline cellulose and contained 0.5 mg parthenolide. The patients used one capsule (feverfew or placebo) a day. Fourty four patients completed the 9 month study. Both treatment groups suffered the same number of migraine attacks. A prophylactic effect could not be demonstrated for our feverfew preparation, but the patients seemed to have a tendency to use fever symptomatic drugs during the period they used feverfew. This result was not in accordance with the results from two other studies. The difference may be explained by the fact that both other studies included patients who previously reported positive experiences with feverfew preparations for migraine prophylaxis., (Copyright © 1996 Gustav Fischer Verlag · Stuttgart · Jena · New York. Published by Elsevier GmbH.. All rights reserved.)

The isolated perfused rat liver preparation was employed to study hepatic disposition of the model drug-carrier conjugate fluorescein-lactosylated albumin (F-LnHSA) with special reference to the influence of the organic anion fluorescein on liver cell specificity of the endocytosed neoglycoprotein. Hepatic clearance of fluoresceinated neoglycoproteins was significantly faster than clearance of radioiodinated neoglycoproteins. Perfusate clearance of F-L7HSA and F-L25HSA could not completely be inhibited by a dose of 10 mg asialoorosomucoid that saturates the hepatocyte receptor-mediated endocytic process. From these data, we inferred an additional hepatic uptake mechanism, competing with the Ashwell-receptor-mediated internalization of galactose-terminated glycoproteins. Clearance experiments with fluoresceinated 125I-human serum albumin in the presence of the polyanionic probe dextran sulfate revealed a nearly complete (approximately 90%) inhibition of hepatic uptake, while also a pronounced effect was obtained with colloidal carbon. These data point to nonparenchymal cell uptake of fluoresceinated protein via interaction with scavenger receptors. In wash-out studies, it was shown that about 25% of ligand sequestrated by sinusoidal liver cells escaped degradation and recycled to the perfusion medium. Our results show that care should be taken in the use of neoglycoproteins as drug carriers to hepatocytes, since a load of only 2 to 3 moles fluorescein per mole neoglycoprotein considerably affects intrahepatic distribution. The relative contribution of nonparenchymal cell uptake by coupling of acidic drugs to the neoglycoproteins is very probably inversely related to the number of exposing galactose groups per molecule neoglycoprotein. This phenomenon of "inversed targeting" could therapeutically both be useful or detrimental, dependent on the spectrum of cell types that should be reached by the drug.