Background and Objective. Clozapine is a second‐generation antipsychotic drug that is considered the most effective treatment for refractory schizophrenia. Several clozapine population pharmacokinetic models have been introduced in the last decades. Thus, a systematic review was performed (i) to compare published pharmacokinetics models and (ii) to summarize and explore identified covariates influencing the clozapine pharmacokinetics models. Methods. A search of publications for population pharmacokinetic analyses of clozapine either in healthy volunteers or patients from inception to April 2019 was conducted in PubMed and SCOPUS databases. Reviews, methodology articles, in vitro and animal studies, and noncompartmental analysis were excluded. Results. Twelve studies were included in this review. Clozapine pharmacokinetics was described as one‐compartment with first‐order absorption and elimination in most of the studies. Significant interindividual variations of clozapine pharmacokinetic parameters were found in most of the included studies. Age, sex, smoking status, and cytochrome P450 1A2 were found to be the most common identified covariates affecting these parameters. External validation was only performed in one study to determine the predictive performance of the models. Conclusions. Large pharmacokinetic variability remains despite the inclusion of several covariates. This can be improved by including other potential factors such as genetic polymorphisms, metabolic factors, and significant drug‐drug interactions in a well‐designed population pharmacokinetic model in the future, taking into account the incorporation of larger sample size and more stringent sampling strategy. External validation should also be performed to the previously published models to compare their predictive performances.
1 September 2020 in Diabetes & Metabolic Syndrome: Clinical Research & Reviews
Background: The impact of Aspergillus on lung disease in young children with cystic fibrosis is uncertain.Aims: To determine if positive respiratory cultures of Aspergillus species are associated with: (1) increased structural lung injury at age 5 years; (2) accelerated lung function decline between ages 5 years and 14 years and (3) to identify explanatory variables.Methods: A cross-sectional analysis of association between Aspergillus positive bronchoalveolar lavage (BAL) cultures and chest high-resolution CT (HRCT) scan findings at age 5 years in subjects from the Australasian Cystic Fibrosis Bronchoalveolar Lavage (ACFBAL) study was performed. A non-linear mixed-effects disease progression model was developed using FEV1% predicted measurements at age 5 years from the ACFBAL study and at ages 6–14 years for these subjects from the Australian Cystic Fibrosis Data Registry.Results: Positive Aspergillus BAL cultures at age 5 years were significantly associated with increased HRCT scores for air trapping (OR 5.53, 95% CI 2.35 to 10.82). However, positive Aspergillus cultures were not associated with either FEV1% predicted at age 5 years or FEV1% predicted by age following adjustment for body mass index z-score and hospitalisation secondary to pulmonary exacerbations. Lung function demonstrated a non-linear decline in this population.Conclusion: In children with cystic fibrosis, positive Aspergillus BAL cultures at age 5 years were associated contemporaneously with air trapping but not bronchiectasis. However, no association was observed between positive Aspergillus BAL cultures on FEV1% predicted at age 5 years or with lung function decline between ages 5 years and 14 years.