ABSTRACT
The authors report a double-blind, placebo-controlled, crossover study of talampanel in 49 patients with refractory partial seizures. Three doses of talampanel were investigated based on differences in patients' concomitant antiepileptic drug usage. Talampanel showed efficacy in reducing seizure frequency (p = 0.001) with a median seizure reduction of 21%. Eighty percent of patients had fewer seizures on talampanel than on placebo. Dizziness (52%) and ataxia (26%) were the only significant adverse events.
Subject(s)
Benzodiazepines/administration & dosage , Epilepsies, Partial/drug therapy , Excitatory Amino Acid Antagonists/administration & dosage , Adult , Anticonvulsants/administration & dosage , Benzodiazepines/adverse effects , Benzodiazepines/pharmacokinetics , Carbamazepine/administration & dosage , Cross-Over Studies , Double-Blind Method , Drug Therapy, Combination , Excitatory Amino Acid Antagonists/adverse effects , Excitatory Amino Acid Antagonists/pharmacokinetics , Female , Humans , Male , Middle Aged , Treatment Outcome , Valproic Acid/administration & dosageABSTRACT
BACKGROUND: The treatment of schizophrenic patients who fail to respond to adequate trials of neuroleptic drugs is a major challenge. Clozapine has been one treatment option; however, it is not universally effective and is limited in its use by safety concerns. With the introduction of newer agents, their performance relative to clozapine is of great clinical interest. METHODS: The primary objective of this study was to evaluate the efficacy and safety of olanzapine versus clozapine among treatment resistant DSM-IV schizophrenic patients. The study was primarily designed to demonstrate the "noninferiority" of olanzapine compared to clozapine after 18 weeks of double-blind treatment. Conclusions were based on the one-sided lower 95% confidence limit about the treatment effect observed from the primary efficacy variable (Positive and Negative Syndrome Scale [PANSS] Total). RESULTS: Mean changes from baseline to end point in PANSS Total score, using a last observation carried forward technique, showed that both agents were comparably effective in neuroleptic resistant patients, i.e., demonstrated the "noninferiority" of olanzapine when compared to clozapine. Overall, significantly fewer olanzapine-treated patients (4%) discontinued for an adverse event than their clozapine-treated (14%) counterparts (p =.022). Among spontaneously reported adverse events, increased salivation, constipation, dizziness, and nausea were reported significantly more often among clozapine-treated patients, whereas only dry mouth was reported more often among olanzapine-treated patients. CONCLUSIONS: Olanzapine was demonstrated to be noninferior to clozapine and better tolerated among resistant schizophrenic patients clinically eligible for treatment with clozapine.
Subject(s)
Antipsychotic Agents/therapeutic use , Clozapine/therapeutic use , Pirenzepine/analogs & derivatives , Pirenzepine/therapeutic use , Schizophrenia/drug therapy , Adult , Antipsychotic Agents/administration & dosage , Antipsychotic Agents/adverse effects , Benzodiazepines , Blood Pressure/drug effects , Body Weight/drug effects , Clozapine/administration & dosage , Clozapine/adverse effects , Double-Blind Method , Drug Resistance , Dyskinesia, Drug-Induced/epidemiology , Female , Humans , Male , Olanzapine , Patient Compliance , Pirenzepine/administration & dosage , Pirenzepine/adverse effects , Psychiatric Status Rating Scales , Schizophrenic Psychology , Time FactorsABSTRACT
BACKGROUND: A relative lack of extrapyramidal symptoms (EPS, i.e., the syndromes of dystonia, parkinsonism, akathisia, dyskinesia) is one criterion used to determine whether an antipsychotic is "atypical." The extrapyramidal symptom profiles of the novel antipsychotic olanzapine and the conventional antipsychotic haloperidol were compared in a population of 2606 patients from three well-controlled prospective clinical trials. METHOD: Extrapyramidal symptom data were analyzed for 1796 patients treated with olanzapine (5 to 20 mg/day) and 810 patients treated with haloperidol (5 to 20 mg/day) for up to 6 weeks of therapy. Patients were monitored weekly by three methods of extrapyramidal symptom assessment: (1) detection of extrapyramidal adverse events (signs and symptoms) by casual observation, nonprobing inquiry, and spontaneous report; (2) objective rating scale scores: and (3) use of concomitant anticholinergic medications. Emergence of EPS was assessed by (1) analysis of the incidence of extrapyramidal syndrome categories based on adverse events, (2) the incidence of extrapyramidal syndromes based on categorical analysis of rating scale scores, (3) analysis of mean maximum change in rating scale scores, and (4) categorical analysis of anticholinergic medication use. Outcome of EPS was assessed by (1) analysis of mean change in rating scale scores at endpoint and (2) mean anticholinergic use at endpoint. RESULTS: Olanzapine was statistically significantly (p = .014, p < .001) superior to haloperidol in all four analyses related to emergence of EPS and in the two analyses related to outcome. Furthermore, during acute treatment, statistically significantly fewer patients treated with olanzapine (0.3%) discontinued the study because of any extrapyramidal adverse event than patients treated with haloperidol (2.7%, p < .001). CONCLUSION: Olanzapine exhibited a statistically significantly lower extrapyramidal symptom profile than the conventional antipsychotic haloperidol at comparably effective antipsychotic doses. The lower extrapyramidal symptom profile with olanzapine was evident despite statistically significantly more frequent use of anticholinergic drugs among haloperidol-treated patients. Fewer olanzapine-treated than haloperidol-treated patients discontinued because of EPS, suggesting that olanzapine should contribute to better compliance with longer term maintenance treatment, with minimal anticholinergic-associated events.
