Safety assessment of combination therapies in the treatment of obesity: focus on naltrexone/bupropion extended release and phentermine-topiramate extended release.

INTRODUCTION: Few studies on combination therapies for the treatment of obesity had been conducted until recently, when two fixed-dose combinations, bupropion-naltrexone ER fixed-dose combination and phentermine-topiramate ER titrated-dose combinations were evaluated in clinical studies that ultimately led to FDA approval. Areas covered: In this review, we discuss safety concerns about both combinations, the rationale and history of combination therapies for obesity (including phentermine plus fenfluramine), and possible future new combinations. Expert opinion: Combination therapies are a promising new area in obesity treatment, similar to what occurs with diabetes and hypertension. Safety assessment is highly important due to the high number of potential users on a chronic basis.

Intrapatient variation in antiepileptic drug plasma concentration after generic substitution vs stable brand-name drug regimens.

Generic substitution of antiepileptic drugs (AEDs) is still a matter of controversy and concern among clinicians and patients. We aimed to assess intrasubject variation in plasma concentrations of lamotrigine (LTG), levetiracetam (LEV) and topiramate (TPM) after generic substitution compared with a stable brand-name drug regimen in a population of patients with epilepsy. A retrospective analysis was performed on prospectively collected and stored data from our therapeutic drug monitoring (TDM) database for the years 2009-2014. The main outcome variable was the proportion of patients who, after switching from branded to generic formulations, showed a greater than ±20% change in AED plasma concentrations compared to the proportion of control patients showing a change in AED plasma concentrations of the same extent while receiving stable branded formulations over repeated TDM tests. Fifty patients on LTG, 27 on LEV and 16 on TPM showing at least one TDM test while receiving generic products fulfilled the inclusion/exclusion criteria for the analysis and were compared with 200 control patients for LTG, 120 for LEV and 80 for TPM. The proportion of patients showing an intrasubject change greater than ±20% in AED plasma concentrations was similar in the brand name vs generic group compared with the control one for LTG (22% vs 33%) and LEV (44% vs 38%), while it was higher in the control group for TPM (41% vs 6%, p<0.01). These are the first data in the literature about the within-patient variation in steady-state plasma concentrations of a series of stable treatments with brand-name AEDs in a real clinical setting. In conclusion, a significant interday variability in intrapatient LTG, LEV and TPM plasma concentrations can be observed even in patients stabilized with the same brand name product over time. This suggests that any change in plasma AED concentration and possible related clinical effects after generic substitution may be not necessarily related to the switch. Our results should be confirmed by large, prospective, blinded, randomized controlled studies in people with epilepsy.

Topiramate-Associated Weight Loss in a Veteran Population.

OBJECTIVE: This study aims to see whether patients in a real-world setting taking topiramate for varied indications experience significant weight loss. METHODS: This was a retrospective cohort study from the Veterans Affairs San Diego Healthcare System. Patients were new topiramate users between January 1, 2000 and December 31, 2013 with body mass index > 25 kg/m(2) and medication possession ratio > 0.5. Primary outcome determined if topiramate users experienced significant changes in weight and body mass index. Secondary outcome analyzed predictive factors associated with 5% weight loss using logistic regression models. Patients were followed up 1 year post index date. RESULTS: A total of 767 patients were included in the final analysis. Patients lost an average of 5.6 lbs (216.1 lbs preweight vs. 210.5 lbs postweight) at an average follow-up of 7.8 months. A total of 43.2% (92/213) of females lost 5% of their body weight compared to 29.4% (163/554) of males. Females (odds ratio 1.73; 95% confidence interval 1.21-2.48; p = 0.003), topiramate indication other than headache, and adherent patients (odds ratio 1.78; 95% confidence interval 1.28-2.49; p = 0.001) were more likely to lose 5% of body weight. CONCLUSION: Topiramate should be considered with higher priority in overweight and obese patients for nonweight loss indications for dual benefit.

Balancing risk and benefit in heavy drinkers treated with topiramate: implications for personalized care.

BACKGROUND: Despite topiramate's ability to reduce heavy drinking, its adverse effects may limit its clinical utility. METHOD: To evaluate the risks and benefits of topiramate, we reanalyzed data from a completed trial of the medication in 138 heavy drinkers whose goal was to reduce their drinking to safe levels. We used the number of patients who had no heavy drinking days during the last 4 weeks of treatment to calculate topiramate's number needed to treat (NNT). To balance the risks and benefits of topiramate, we adjusted the NNT using 2 different levels of adverse event severity: moderate or greater (NNT-AEmod+) and severe or greater (NNT-AEsev+). This measure helps to guide the clinical use of topiramate in heavy drinkers by incorporating both its beneficial and adverse effects in a single measure. Because a polymorphism (rs2832407) in the gene encoding a kainate receptor subunit appears to moderate topiramate's effects in heavy drinkers, we repeated the analyses based on rs2832407 genotype (C-homozygote vs A-allele carrier) in the European American subsample (n = 122). RESULTS: Overall, the NNT for topiramate was 5.29, the NNT-AEmod+ was 7.52, and the NNT-AEsev+ was 6.12. Among European Americans with the rs2832407*CC genotype, the NNT was 2.28, the NNT-AEmod+ was 2.63, and the NNT-AEsev+ was 2.56. In contrast, for rs2832407*A-allele carriers, the NNT was 180.00, the NNT-AEmod+ was 322.16, and the NNT-AEsev+ was 217.45. CONCLUSIONS: In this sample of heavy drinkers, topiramate had a clinically important treatment effect that was most evident in European Americans with the rs2832407*CC genotype. In that group, in particular, it had a robust treatment effect, even when adjusted for adverse events. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT00626925.

Assessment of the quality of harms reporting in non-randomised studies and randomised controlled studies of topiramate for the treatment of epilepsy using CONSORT criteria.

PURPOSE: Treatment decisions should be informed by high quality evidence of both the potential benefit and harms of treatment alternatives. Randomised controlled trials (RCTs) provide the best evidence regarding benefits; however information relating to serious, rare and long-term harms is usually available only from non-randomised studies (NRSs). The aim of this study was to use a checklist based on the CONSORT (Consolidating Standards for Reporting Trials) extension for harms recommendations to assess the quality of reporting of harms data in both NRSs and RCTs of antiepileptic drugs, using studies of topiramate as an example. RESULTS: Seventy-eight studies were included from an online search of seven databases. Harms data was extracted from each study using a 25-point checklist. The mean number of items met was 11.5 (SD 2.96) per study. Commercially funded studies met on average 12.7 items and non-commercially funded studies met 10.08 (p value < 0.001). RCTs met on average 13.0 items and NRSs met 10.8 (p = 0.001). Multi-centre studies and commercially funded studies met significantly more items than single centre and non-commercially funded studies respectively. There was no significant difference in the mean number of items met by studies that had included adult vs. child participants, or studies published pre- vs. post-CONSORT extension for harms in 2004. CONCLUSIONS: Reporting of harms is significantly better in RCTs than in NRSs of TPM, but is suboptimal overall and has not improved since the publication of CONSORT extension for harms in 2004. There is a need to improve the reporting of harms in order to better inform treatment decisions.

Assessment and treatment of insomnia in adult patients with alcohol use disorders.

Insomnia in patients with alcohol dependence has increasingly become a target of treatment due to its prevalence, persistence, and associations with relapse and suicidal thoughts, as well as randomized controlled studies demonstrating efficacy with behavior therapies and non-addictive medications. This article focuses on assessing and treating insomnia that persists despite 4 or more weeks of sobriety in alcohol-dependent adults. Selecting among the various options for treatment follows a comprehensive assessment of insomnia and its multifactorial causes. In addition to chronic, heavy alcohol consumption and its effects on sleep regulatory systems, contributing factors include premorbid insomnia; co-occurring medical, psychiatric, and other sleep disorders; use of other substances and medications; stress; environmental factors; and inadequate sleep hygiene. The assessment makes use of history, rating scales, and sleep diaries as well as physical, mental status, and laboratory examinations to rule out these factors. Polysomnography is indicated when another sleep disorder is suspected, such as sleep apnea or periodic limb movement disorder, or when insomnia is resistant to treatment. Sobriety remains a necessary, first-line treatment for insomnia, and most patients will have some improvement. If insomnia-specific treatment is needed, then brief behavioral therapies are the treatment of choice, because they have shown long-lasting benefit without worsening of drinking outcomes. Medications work faster, but they generally work only as long as they are taken. Melatonin agonists; sedating antidepressants, anticonvulsants, and antipsychotics; and benzodiazepine receptor agonists each have their benefits and risks, which must be weighed and monitored to optimize outcomes. Some relapse prevention medications may also have sleep-promoting activity. Although it is assumed that treatment for insomnia will help prevent relapse, this has not been firmly established. Therefore, insomnia and alcohol dependence might be best thought of as co-occurring disorders, each of which requires its own treatment.

Cost-effectiveness analysis of interventions for migraine in four low- and middle-income countries.

BACKGROUND: Evidence of the cost and effects of interventions for reducing the global burden of migraine remains scarce. Our objective was to estimate the population-level cost-effectiveness of evidence-based migraine interventions and their contributions towards reducing current burden in low- and middle-income countries. METHODS: Using a standard WHO approach to cost-effectiveness analysis (CHOICE), we modelled core set intervention strategies for migraine, taking account of coverage and efficacy as well as non-adherence. The setting was primary health care including pharmacies. We modelled 26 intervention strategies implemented during 10 years. These included first-line acute and prophylactic drugs, and the expected consequences of adding consumer-education and provider-training. Total population-level costs and effectiveness (healthy life years [HLY] gained) were combined to form average and incremental cost-effectiveness ratios. We executed runs of the model for the general populations of China, India, Russia and Zambia. RESULTS: Of the strategies considered, acute treatment of attacks with acetylsalicylic acid (ASA) was by far the most cost-effective and generated a HLY for less than US$ 100. Adding educational actions increased annual costs by 1-2 US cents per capita of the population. Cost-effectiveness ratios then became slightly less favourable but still less than US$ 100 per HLY gained for ASA. An incremental cost of > US$ 10,000 would have to be paid per extra HLY by adding a triptan in a stepped-care treatment paradigm. For prophylaxis, amitriptyline was more cost-effective than propranolol or topiramate. CONCLUSIONS: Self-management with simple analgesics was by far the most cost-effective strategy for migraine treatment in low- and middle-income countries and represents a highly efficient use of health resources. Consumer education and provider training are expected to accelerate progress towards desired levels of coverage and adherence, cost relatively little to implement, and can therefore be considered also economically attractive. Evidence-based interventions for migraine should have as much a claim on scarce health resources as those for other chronic, non-communicable conditions that impose a significant burden on societies.

Cost-Effectiveness Analysis of Qsymia for Weight Loss.

BACKGROUND: Phase 3 clinical trial results reveal that Qsymia is a clinically effective long-term treatment for obesity, but whether this treatment is cost-effective compared to a diet and lifestyle intervention has yet to be explored. OBJECTIVE: To quantify the incremental cost-effectiveness of Qsymia (phentermine and topiramate extended-release) for health-related quality of life improvements. STUDY DESIGN AND METHODS: Estimates are based on cost and quality of life outcomes from a 56-week, multicenter, placebo-controlled, phase 3 clinical trial undertaken in 93 health centers in the US. Participants were overweight and obese adults (aged 18-70 years) with a body-mass index of 27-45 kg/m(2) and two or more comorbidities (hypertension, dyslipidemia, diabetes or pre-diabetes or abdominal obesity). The intervention was diet and lifestyle advice plus the recommended dose of Qsymia (phentermine 7.5 mg plus topiramate 46.0 mg) vs. control, which included diet and lifestyle advice plus placebo. The study was from the payer perspective. Costs included the prescription cost, medication cost offsets and physician appointment costs. Effectiveness was measured in terms of quality-adjusted life years gained (QALYs). The main outcome measure was incremental cost per QALY gained of the intervention relative to control. RESULTS: Our base-case model, in which participants take Qsymia for 1 year with benefits linearly decaying over the subsequent 2 years, generates an incremental cost-effectiveness ratio (ICER) of $48,340 per QALY gained. Using the base-case assumptions, probabilistic sensitivity analyses reveal that the ICER is below $50,000 per QALY in 54 % of simulations. However, results are highly dependent on the extent to which benefits are maintained post medication cessation. If benefits persist for only 1 year post cessation, the ICER increases to $74,480. CONCLUSION: Although base-case results suggest that Qsymia is cost-effective, this result hinges on the time on Qsymia and the extent to which benefits are maintained post medication cessation. This should be an area of future research.

The Paediatric migraine disability assessment score is a useful tool for evaluating prophylactic migraine treatment.

AIM: There is a need for an objective assessment scoring system to evaluate the effectiveness of prophylactic drugs in paediatric migraine, and the aim of this study was to evaluate the Paediatric Migraine Disability Assessment Score (PedMIDAS). METHODS: We recruited 88 children aged between 6 and 17 years of age with migraine. The 53 children in the treatment group were divided into three groups according to the prophylactic drug they received topiramate, flunarizine and propranolol and assessed using PedMIDAS before the start of treatment and 3 and 6 months after treatment. The 35 patients in the control group did not receive prophylactic treatment and were assessed with PedMIDAS on three occasions, 3 months apart. RESULTS: Topiramate, propranolol and flunarizine treatments significantly decreased PedMIDASs and were shown to be effective in improving the patients' quality of life. Topiramate and propranolol were more effective than flunarizine. The number of days on analgesic treatment significantly decreased in the patients who had received topiramate and propranolol treatments (p < 0.05), but remained unchanged in the flunarizine prophylaxis group (p > 0.05). CONCLUSION: The PedMIDAS scoring system is useful in evaluating the efficacy of prophylactic therapy in paediatric migraine. Topiramate and propranolol lowered the PedMIDASs better than flunarizine.

Antiepileptic drug utilization in Bangladesh: experience from Dhaka Medical College Hospital.

BACKGROUND: Epilepsy is a common health problem which carries a huge medical social psychological and economic impact for a developing country. The aim of this hospital-based study was to get an insight into the effectiveness and tolerability of low cost antiepileptic drugs (AEDs) in Bangladeshi people with epilepsy. METHODS: This retrospective chart review was done from hospital records in weekly Epilepsy outdoor clinic of Department of Neurology, Dhaka Medical College Hospital (DMCH) from October 1998 to February 2013. A total of 854 epilepsy patients met the eligibility criteria (had a complete record of two years of follow up data) from hospital database. A checklist was used to take demographics (age and gender), epilepsy treatment and adverse event related data. At least two years of follow up data were considered for analysis. RESULTS: Out of 854 patients selected, majority of the patients attending outdoor clinic were >11-30 years age group (55.2%) with a mean age of 20.3 ± 9 years and with a male (53%) predominance. Focal epilepsy were more common (53%), among whom secondary generalized epilepsy was the most frequent diagnosis (67%) followed by complex partial seizure (21%). Among those with Idiopathic Generalized Epilepsy (46%), generalized tonic clonic seizure was encountered in 74% and absence seizure was observed in 13%. The number of patients on monotherapy and dual AED therapy were 67% and 24% respectively and polytherapy (i.e. >3 AEDs) was used only in 9%. CBZ (67%) was the most frequently prescribed AED, followed by VPA (43%), PHB (17%), and PHT (8%). CBZ was prescribed in 37% patients as monotherapy followed by VPA in 21% and PHB in 8% patients. Newer generation drugs eg lemotrigine and topiramate were used only as add on therapy in combination with CBZ and VPA in only 2% patients. The treatment retention rates over the follow up period for the AEDs in monotherapy varied between 86 and 91% and were highest for CBZ, followed by VPA. Most of the combination regimens had a treatment retention rate of 100%. The effectiveness of AED in terms of reduction of seizure frequency was highest for PHT (100%) and PHB (98%) followed by CBZ (96%) and VPA (95%). PHB and PHT were the cheapest of all AEDs (42 I$ and 56 I$/ year respectively). The costs of VPA and CBZ were two times and LTG and TOP were six to eight times higher. Adverse drug reaction (ADR) were observed among 140 (24.5%) of those with monotherapy. PHT (64%) was the most common drug to cause ADR, CBZ was at the bottom of the list to cause adverse effect (11.6%). VPA and PHB caused weight gain commonly. Adjustment of drug dose or withdrawal due to ADRs was necessary in 39% with PHT and 26% with PHB. CONCLUSION: Though PHT and PHB are cheapest and efficacious among all, CBZ and VPA are less costly, effective and well tolerated drug for seizure control in context of Bangladesh.

Obesity drug therapy.

Obesity is a chronic disease, and it requires chronic therapy. Hypertension, dyslipidemia, diabetes and cardiovascular diseases are leading causes of mortality in the modern world. All of them are strongly linked to obesity. While treating obesity, those conditions are also managed. Obese patients should always be treated through lifestyle interventions, though the results of such interventions are modest. Pharmacotherapy is a second step in the treatment of obesity, approved only when weight loss targets were not reached through lifestyle intervention. During the history of antiobesity drugs, many of them were withdrawn because of their side effects. Various guidelines recommend prescribing drug therapy for obesity through consideration of the potential benefits and limitations. Orlistat deactivates intestinal lipase and inhibits intestinal fat lipolysis. It is actually the only drug on the European market approved for the treatment of obesity. Orlistat therapy reduces weight to a modest extent, but it reduces the incidence of diabetes beyond the result achieved with lifestyle changes. Recently, some effective antiobesity drugs like sibutramine and rimonabant have been removed from the market due to their side effects. The new combination of topimarate and fentermine is approved in the US but not in Europe. The cost effectiveness of long-term pharmacotherapy of obesity is still an unresolved question.

Two center, randomized pilot study of migraine prophylaxis comparing paradigms using pre-emptive frovatriptan or daily topiramate: research and clinical implications.

OBJECTIVE: To compare the efficacy and clinical benefit of 2 paradigms of migraine prevention using pre-emptive frovatriptan and daily topiramate. The study compares the paradigms of pre-emptive use of frovatriptan, a drug approved for acute migraine, and the daily use of topiramate, a Federal Drug Administration-approved and -accepted standard for migraine prophylaxis. BACKGROUND: Traditionally, preventive treatment of migraine required daily medication. However, recent studies suggest that pre-emptive prophylaxis may be beneficial to those migraineurs who can predict an attack of migraine based on premonitory symptoms and treat during that phase. METHODS: A total of 76 adult subjects with a diagnosis of migraine were screened for the study. During a 1-month baseline period, subjects demonstrated through a daily diary that they predicted at least 50% of migraine attacks during the premonitory phase and treated with their usual medication. Of these, 55 were randomized to either Group A (daily topiramate) or Group B (frovatriptan during premonitory symptoms); 44 completed the study. The treatment period lasted 2 months. The subjects answered the Migraine-Specific Quality of Life Questionnaire at randomization, and at Weeks 4 and 8. The revised Patient Perception of Migraine Questionnaire was answered 24 hours after taking frovatriptan (Group A, for break-through headaches; Group B, treatment during premonitory symptoms). RESULTS: The number of migraine attacks and headache days per month decreased significantly from baseline for both Groups A and B. Subjects in Group A had considerably more adverse events leading to study withdrawal than in Group B (18% vs 4%). Though this study was not powered to directly compare the efficacy of the 2 drugs, topiramate showed superiority over frovatriptan at Month 2 in reduction of headache days, which was a secondary end point in the study (P = .036). CONCLUSIONS: This pilot study demonstrated that statistical benefit for reduction of headache days over baseline for both pre-emptive frovatriptan and daily topiramate. Subjects utilizing pre-emptive frovatriptan experienced fewer adverse events leading to study withdrawal. Subjects utilizing daily topiramate had fewer headache days at Month 2.

Long-term assessment of topiramate for epilepsy: an open-label, single-arm, multicentre, prospective study in a naturalistic setting.

BACKGROUND AND OBJECTIVE: Most patients with epilepsy require long-term medical therapy. Newer antiepileptic drugs (AEDs) appear to be overall similarly effective to older agents but may be better tolerated. However, most of the clinical data available for newer AEDs derive from a number of short-term studies. The objective of this study was to explore long-term outcomes in patients with epilepsy treated with topiramate in routine clinical practice. METHODS: This was an open-label, multicentre, optional follow-up monotherapy study that included adolescents and adults with epilepsy who completed two similarly designed 28- or 30-week studies and agreed to participate for an additional 52 weeks. Seizure types and frequency, topiramate dose, vital signs and treatment-emergent adverse events (TEAEs) after 12, 26, 39 and 52 weeks were documented. Post hoc analyses to explore differences between males and females were conducted. RESULTS: 114 patients (49.0% women, mean ± SD age 43 ± 17.5 years) with a mean ± SD disease duration of 61 ± 118 months (men 54 ± 96 vs women 68 ± 138 months) were followed up for a median of 18.5 months. Seventy-eight percent of patients completed the study. Reasons for premature discontinuation were: loss to follow-up (10.5%), TEAE (5.3%), lack of efficacy (2.6%), non-adherence (0.9%) and other reasons (4.4%). Seizure frequency per 4 weeks decreased from a mean ± SD 5.0 ± 28.3 at baseline to 0.6 ± 2.1 during the whole observation period. Fifty-four patients (52.9%) were seizure free during the whole observation period. In addition, 69 of 95 patients (72.6%) whose topiramate therapy was stable within a range of ±50 mg/day for a period of at least 12 months (maintenance phase) were seizure free while treated with a median topiramate dose of 100 mg/day. The most frequently reported TEAEs were paraesthesias (13.2% of patients), dizziness (7.0%) and seizure-related events (7.0%). No significant differences between males and females were found for treatment response or retention. CONCLUSION: Topiramate is an effective and well tolerated long-term treatment option for adolescents and adults with epilepsy.

Clinical comparability of the new antiepileptic drugs in refractory partial epilepsy: a systematic review and meta-analysis.

PURPOSE: Evaluate the clinical comparability of new antiepileptic drugs (AEDs) in partial refractory epilepsy. METHODS: Systematic review of randomized trials (RCTs) comparing a new AED (add-on treatment) with placebo or another AED. PRIMARY OUTCOMES: responder (≥50% seizure reduction) and withdrawal (tolerability) rates. Pooled estimates of odds ratios (ORs) and number needed treat/harm (NNT/NNH) taking into account baseline risk were derived by random-effects meta-analysis. Adjusted frequentist indirect comparisons between AEDs were estimated. KEY FINDINGS: Sixty-two placebo-controlled (12,902 patients) and eight head-to-head RCTs (1,370 patients) were included. Pooled ORs for responder and withdrawal rates (vs. placebo) were 3.00 [95% confidence interval (CI) 2.63-3.41] and 1.48 (1.30-1.68), respectively. Indirect comparisons of responder rate based on relative measurements of treatment effect (ORs) favored topiramate (1.52; 1.06-2.20) in comparison to all other AEDs, whereas gabapentin (0.67; 0.46-0.97) and lacosamide (0.66; 0.48-0.92) were less efficacious, without significant heterogeneity. When analyses were based on absolute estimates (NNTs), topiramate and levetiracetam were more efficacious, whereas gabapentin and tiagabine were less efficacious. Withdrawal rate was higher with oxcarbazepine (OR 1.60; 1.12-2.29) and topiramate (OR 1.68; 1.07-2.63), and lower with gabapentin (OR 0.65; 0.42-1.00) and levetiracetam (OR 0.62; 0.43-0.89). SIGNIFICANCE: The differences found are of relatively small magnitude to allow a definitive conclusion about which new AED(s) has superior effectiveness. This uncertainty probably reflects the limitations of conclusions based on indirect evidence. The process of pharmacologic clinical decision making in partial refractory epilepsy probably depends more on other aspects, such as individual patient characteristics and pharmacoeconomics, than on available controlled randomized evidence.

Assessment of the potential of a boron-fructose additive in counteracting the toxic effect of Fusarium mycotoxins.

Trichotecenes are mycotoxins produced by Fusarium sp., which may contaminate animal feeds and human food. A feeding trial was conducted to evaluate the effect of a fusarotoxin-contaminated diet, and to explore the counteracting potential of a calcium fructoborate (CFrB) additive on performance, typical health biochemistry parameters and immune response in weaned pigs. A naturally contaminated maize, containing low doses of deoxynivalenol, zearalenone, fumonisins and T-2/HT-2 toxins (1790, 20, 0·6 and 90 parts per billion), was included in a maize-soyabean meal diet, and given ad libitum to eight weaned piglets (two groups: four pigs/group) for a period of 24 d. CFrB was administered to one of the contaminated groups and to another four piglets as a daily supplement, following the manufacturer's recommendation. A decrease in performance was observed in contaminated animals at this concentration of feed toxins, which was ameliorated by the dietary CFrB supplementation. Fusarium toxins also altered the pig immune response by increasing (P < 0·05) the ex vivo peripheral blood mononuclear cell proliferation (111·7 % in comparison with control), the respiratory burst of porcine granulocytes (15·4 % for responsive cells v. 5·1 % for unstimulated cells and 70·95 v. 22·65 % for stimulated cells, respectively), the percentage of peripheral T, CD3(+), CD3(+)CD4(+) and CD3(+)CD8(+) subsets and the synthesis of IL-1ß, TNF-α and IL-8 (123·8, 217·1 and 255·1 %, respectively). The diet containing the CFrB additive reduced these exacerbated cellular immune responses induced by Fusarium toxins. However, consumption of CFrB did not counteract the effect of mycotoxins on biochemistry parameters, and increased plasma IgM and IgG of contaminated pigs.

Metabolic acidosis with topiramate and zonisamide: an assessment of its severity and predictors.

OBJECTIVE: Carbonic anhydrase (CA) inhibitors topiramate and zonisamide can induce metabolic acidosis in some patients. Our aims were to assess the prevalence and severity of this acidosis and to determine its predictors. METHODS: For 70 patients established on treatment with topiramate (n=55) or zonisamide (n=14) or both (n=1), we measured electrolytes, and genotyped single nucleotide polymorphisms (SNPs) in the main renal CA isoenzymes (II, IV and XII). RESULTS: Twenty-six percent of patients had a metabolic acidosis (serum bicarbonate <20 mmol/l). The mean serum bicarbonate of patients taking topiramate was significantly lower than those taking zonisamide (P=0.002). We found no association between serum bicarbonate and the dose of drug or the duration of treatment. Serum bicarbonate levels were associated with the CA type XII SNPs rs2306719 (P=0.006 by one-way analysis of variance) and rs4984241 (P=0.015), but this association was not strong enough to survive correction for multiple testing. CONCLUSION: The development of acidosis with topiramate and zonisamide is not determined by drug dose or by treatment duration, but may be influenced by polymorphisms in the gene for CA type XII. The aforementioned SNPs lie 9.8 kb apart in intron 1 of the CA type XII gene, and deserve further study in a larger cohort of patients.