AIMS: Abiraterone treatment requires regular drug intake under fasting conditions due to pronounced food effect, which may impact patient adherence. The aim of this prospective study was to evaluate adherence to abiraterone treatment in patients with prostate cancer. To achieve this aim, an abiraterone population pharmacokinetic model was developed and patients' adherence has been estimated by comparison of measured levels of abiraterone with population model-based simulations. METHODS: A total of 1469 abiraterone plasma levels from 83 healthy volunteers collected in a bioequivalence study were analysed using a nonlinear mixed-effects model. Monte Carlo simulation was used to describe the theoretical distribution of abiraterone pharmacokinetic profiles at a dose of 1000 mg once daily. Adherence of 36 prostate cancer patients treated with abiraterone was then evaluated by comparing the real abiraterone concentration measured in each patient during follow-up visit with the theoretical distribution of profiles based on simulations. Patients whose abiraterone levels were ˂5th or ˃95th percentile of the distribution of simulated profiles were considered to be non-adherent. RESULTS: Based on this evaluation, 13 patients (36%) have been classified as non-adherent. We observed significant association (P = .0361) between richness of the breakfast and rate of non-adherence. Adherent patients reported significantly better overall condition in self-assessments (P = .0384). A trend towards a higher occurrence of adverse effects in non-adherent patients was observed. CONCLUSIONS: We developed an abiraterone population pharmacokinetic model and proposed an advanced approach to medical adherence evaluation. Due to the need for administration under fasting conditions, abiraterone therapy is associated with a relatively high rate of non-adherence.
- MeSH
- adherence k farmakoterapii * statistika a číselné údaje MeSH
- androsteny * farmakokinetika aplikace a dávkování terapeutické užití MeSH
- antitumorózní látky farmakokinetika aplikace a dávkování MeSH
- biologické modely * MeSH
- dospělí MeSH
- interakce mezi potravou a léky MeSH
- lidé středního věku MeSH
- lidé MeSH
- metoda Monte Carlo MeSH
- nádory prostaty * farmakoterapie MeSH
- omezení příjmu potravy MeSH
- prospektivní studie MeSH
- senioři MeSH
- terapeutická ekvivalence MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- Publikační typ
- časopisecké články MeSH
Kastračně rezistentní karcinom prostaty (castrate-resistant prostate cancer, CRPC) bez průkazu metastazujícího onemocnění klasifikujeme jako nemetastazující CRPC (nmCRPC). Pacienti s nmCRPC progredují do metastazujícího onemocnění a jsou ohroženi vznikem symptomů z důvodu progrese onkologického onemocnění (bolesti, patologické fraktury apod.). Hlavním cílem léčby nmCRPC je prodloužení doby do vzniku metastazujícího onemocnění. Druhá generace inhibitorů androgenních receptorů, kam patří apalutamid, enzalutamid a darolutamid, prokázala prodloužení doby do vzniku metastazujícího onemocnění a prodloužení celkového přežití ve srovnání s placebem u pacientů s nmCRPC. Darolutamid má unikátní strukturu s nízkou penetrací přes hematoencefalickou bariéru. Má příznivější bezpečnostní profil než další dva androgenní receptory druhé generace.
Castration-resistant prostate cancer (CRPC) without any metastases on conventional imaging is classified as non-metastatic CRPC (nmCRPC). Patients with nmCRPC progress to metastatic disease and are at risk of developing cancer-related symptoms (pain, pathological bone fractures etc.). Effective management of nmCRPC should aim to delay metastatic progression. Second generation androgen receptor inhibitors (apalutamide, enzalutamide and darolutamide) have been demonstrated the longer median of metastases free survival and overall survival than placebo in patients with nmCRPC. Darolutamide is a structurally unique androgen receptor inhibitor with low penetration of blood-brain barrier and lower incidence of adverse events than others androgen receptor inhibitors.
- Klíčová slova
- darolutamid,
- MeSH
- analýza přežití MeSH
- antagonisté androgenních receptorů farmakologie terapeutické užití MeSH
- lidé MeSH
- nádory prostaty rezistentní na kastraci * farmakoterapie sekundární MeSH
- prostatický specifický antigen MeSH
- protokoly protinádorové léčby MeSH
- pyrazoly farmakologie terapeutické užití MeSH
- randomizované kontrolované studie jako téma MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
The aim of this study was to improve rivaroxaban water-solubility by cocrystal preparation and to understand this process. The screening with water-soluble coformers was performed via both mechanochemical and solution-mediated techniques. Two cocrystals of rivaroxaban with malonic acid and oxalic acid were prepared, and the structure of the cocrystal with oxalic acid was solved. Both cocrystals exhibit improved dissolution properties. The mechanism of the supersaturation maintenance was studied by in-situ Raman spectroscopy. The transformation into rivaroxaban dihydrate was identified as the critical step in the improved dissolution properties of both cocrystals. Moreover, the transformation kinetics and solubilization effects of the coformers were identified as responsible for the differences in the dissolution behavior of the cocrystals. In-vivo experiments proved that the use of cocrystal instead of form I of free API helped to increase the bioavailability ofrivaroxaban.
One of the major concerns for all in vivo experiments is intra- and inter-subject variability, which can be a great source of inaccuracy. The aim of this study is, therefore, to estimate the ability of parallel vs. cross-over design studies in order to describe the relative pharmacokinetic performance of the studied drug formulations. We analyzed the data from a drug development program that examined the performance of innovative abiraterone acetate formulations against the identical reference product in three stages. In stages 1-3, groups A-F were dosed with the reference product once in a parallel manner. Stage 4 was performed to evaluate the intra-individual variability (IIV) by repeated administration of the reference product to the same animals. Although the geometric mean (90% CI) values of abiraterone AUClast in groups A-F were similar to the IIV group (24.36 (23.79-41.00) vs. 26.29 (20.56-47.00) mg/mL·min·g), the results generated in the isolated parallel groups provided imprecise estimates of the true AUClast values ranging from 9.62 to 44.62 mg/mL·min·g due to chance. Notably, in 4 out of 15 possible pair comparisons between the parallel groups, the confidence intervals did not include 100%, which is the true ratio for all comparisons tested after identical formulation administration to all groups. A cross-over design can significantly improve the methodology in short-term comparative pre-clinical pharmacokinetic studies, and can provide more precise and accurate results in comparison to more traditional pre-clinical study designs.
- Publikační typ
- časopisecké články MeSH
BACKGROUND AND PURPOSE: Lymphatic transport of drugs after oral administration is an important mechanism for absorption of highly lipophilic compounds. Direct measurement in lymph duct cannulated animals is the gold standard method, but non-invasive cycloheximide chylomicron flow blocking method has gained popularity recently. However, concerns about its reliability have been raised. The aim of this work was to investigate the validity of cycloheximide chylomicron flow blocking method for the evaluation of lymphatic transport using model compounds with high to very high lipophilicity, that is, abiraterone and cinacalcet. EXPERIMENTAL APPROACH: Series of pharmacokinetic studies were conducted with abiraterone acetate and cinacalcet hydrochloride after enteral/intravenous administration to intact, lymph duct cannulated and/or cycloheximide pre-treated rats. KEY RESULTS: Mean total absolute oral bioavailability of abiraterone and cinacalcet was 7.0% and 28.7%, respectively. There was a large and significant overestimation of the lymphatic transport extent by the cycloheximide method. Mean relative lymphatic bioavailability of abiraterone and cinacalcet in cycloheximide method was 28-fold and 3-fold higher than in cannulation method, respectively. CONCLUSION AND IMPLICATIONS: Cycloheximide chylomicron flow blocking method did not provide reliable results on lymphatic absorption and substantially overestimated lymphatic transport for both molecules, that is, abiraterone and cinacalcet. This non-invasive method should not be used for the assessment of lymphatic transport and previously obtained data should be critically revised.
- MeSH
- aplikace orální MeSH
- biologická dostupnost MeSH
- biologický transport MeSH
- chylomikrony * metabolismus MeSH
- cykloheximid farmakologie MeSH
- intestinální absorpce * MeSH
- krysa rodu rattus MeSH
- léčivé přípravky MeSH
- reprodukovatelnost výsledků MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Ca2+-insensitive and -sensitive E1 subunits of the 2-oxoglutarate dehydrogenase complex (OGDHC) regulate tissue-specific NADH and ATP supply by mutually exclusive OGDH exons 4a and 4b. Here we show that their splicing is enforced by distant lariat branch points (dBPs) located near the 5' splice site of the intervening intron. dBPs restrict the intron length and prevent transposon insertions, which can introduce or eliminate dBP competitors. The size restriction was imposed by a single dominant dBP in anamniotes that expanded into a conserved constellation of four dBP adenines in amniotes. The amniote clusters exhibit taxon-specific usage of individual dBPs, reflecting accessibility of their extended motifs within a stable RNA hairpin rather than U2 snRNA:dBP base-pairing. The dBP expansion took place in early terrestrial species and was followed by a uridine enrichment of large downstream polypyrimidine tracts in mammals. The dBP-protected megatracts permit reciprocal regulation of exon 4a and 4b by uridine-binding proteins, including TIA-1/TIAR and PUF60, which promote U1 and U2 snRNP recruitment to the 5' splice site and BP, respectively, but do not significantly alter the relative dBP usage. We further show that codons for residues critically contributing to protein binding sites for Ca2+ and other divalent metals confer the exon inclusion order that mirrors the Irving-Williams affinity series, linking the evolution of auxiliary splicing motifs in exons to metallome constraints. Finally, we hypothesize that the dBP-driven selection for Ca2+-dependent ATP provision by E1 facilitated evolution of endothermy by optimizing the aerobic scope in target tissues.
- MeSH
- alternativní sestřih * MeSH
- exony MeSH
- HEK293 buňky MeSH
- introny * MeSH
- ketoglutarátdehydrogenasový komplex genetika metabolismus MeSH
- lidé MeSH
- messenger RNA chemie metabolismus MeSH
- místa sestřihu RNA MeSH
- molekulární evoluce MeSH
- obratlovci genetika MeSH
- prekurzory RNA chemie metabolismus MeSH
- protein - isoformy genetika metabolismus MeSH
- rozptýlené repetitivní sekvence MeSH
- sestřihové faktory metabolismus MeSH
- spliceozomy metabolismus MeSH
- termoregulace genetika MeSH
- vápník metabolismus MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Kastračně rezistentní karcinom prostaty (CRPC) bez průkazu metastatického onemocnění dle standardních zobrazovacích metod (CT a scintigrafie skeletu) klasifikujeme jako nemetastatický CRPC (nmCRPC). Hlavním rizikem nmCRPC je progrese do metastatického onemocnění, které je spojeno s rozvojem komplikací a sníženou kvalitou života. Hlavním smyslem terapie nmCRPC je proto prodloužení doby do vzniku metastatického stadia. Proběhly tři význa-né prospektivní klinické studie III. fáze, které u pacientů s nmCRPC prokázaly prodloužení doby do vzniku metastáz i prodloužení celkového přežití. Studie hodnotily antiandr-geny 2. generace, mezi něž patří apalutamid, enzalutamid a darolutamid. Darolutamid má unikátní strukturu s nízkou penetrací přes hematoencefalickou bariéru a příznivějším bezpečnostním profilem než další dva antiandrogeny 2. g-nerace. V naší klinické praxi jsme začali pacienty darolut-midem léčit od července 2021 a zde uvádíme první klinické zkušenosti.
Castration-resistant prostate cancer (CRPC) without evidence of metastatic disease according to standard imaging methods (CT and skeletal scintigraphy) is classified as non-metastatic CRPC (nmCRPC). The main risk of nmCRPC is progression to metastatic disease, which is associated with the development of complications and reduced quality of life. Therefore, the main purpose of nmCRPC therapy is to prolong the time to the metastatic stage. There have been three major prospective phase III clinical trials that have demonstrated prolongation of time to the development of metastasis and overall survival in patients with nmCRPC. These studies evaluated second- -generation antiandrogens, which include apalutamide, enzalutamide and darolutamide. Darolutamide has a unique structure with low penetration across the blood- -brain barrier and a more favourable safety profile than the other two second-generation antiandrogens. In our clinical practice, we have treated patients with darolutamide since July 2021 and here we present our first clinical experience.
U2AF65 (U2AF2) and PUF60 (PUF60) are splicing factors important for recruitment of the U2 small nuclear ribonucleoprotein to lariat branch points and selection of 3' splice sites (3'ss). Both proteins preferentially bind uridine-rich sequences upstream of 3'ss via their RNA recognition motifs (RRMs). Here, we examined 36 RRM substitutions reported in cancer patients to identify variants that alter 3'ss selection, RNA binding and protein properties. Employing PUF60- and U2AF65-dependent 3'ss previously identified by RNA-seq of depleted cells, we found that 43% (10/23) and 15% (2/13) of independent RRM mutations in U2AF65 and PUF60, respectively, conferred splicing defects. At least three RRM mutations increased skipping of internal U2AF2 (~9%, 2/23) or PUF60 (~8%, 1/13) exons, indicating that cancer-associated RRM mutations can have both cis- and trans-acting effects on splicing. We also report residues required for correct folding/stability of each protein and map functional RRM substitutions on to existing high-resolution structures of U2AF65 and PUF60. These results identify new RRM residues critical for 3'ss selection and provide relatively simple tools to detect clonal RRM mutations that enhance the mRNA isoform diversity.
- Publikační typ
- časopisecké články MeSH
PUF60 is a splicing factor that binds uridine (U)-rich tracts and facilitates association of the U2 small nuclear ribonucleoprotein with primary transcripts. PUF60 deficiency (PD) causes a developmental delay coupled with intellectual disability and spinal, cardiac, ocular and renal defects, but PD pathogenesis is not understood. Using RNA-Seq, we identify human PUF60-regulated exons and show that PUF60 preferentially acts as their activator. PUF60-activated internal exons are enriched for Us upstream of their 3' splice sites (3'ss), are preceded by longer AG dinucleotide exclusion zones and more distant branch sites, with a higher probability of unpaired interactions across a typical branch site location as compared to control exons. In contrast, PUF60-repressed exons show U-depletion with lower estimates of RNA single-strandedness. We also describe PUF60-regulated, alternatively spliced isoforms encoding other U-bound splicing factors, including PUF60 partners, suggesting that they are co-regulated in the cell, and identify PUF60-regulated exons derived from transposed elements. PD-associated amino-acid substitutions, even within a single RNA recognition motif (RRM), altered selection of competing 3'ss and branch points of a PUF60-dependent exon and the 3'ss choice was also influenced by alternative splicing of PUF60. Finally, we propose that differential distribution of RNA processing steps detected in cells lacking PUF60 and the PUF60-paralog RBM39 is due to the RBM39 RS domain interactions. Together, these results provide new insights into regulation of exon usage by the 3'ss organization and reveal that germline mutation heterogeneity in RRMs can enhance phenotypic variability at the level of splice-site and branch-site selection.
- MeSH
- aminokyselinové motivy MeSH
- exony * MeSH
- HEK293 buňky MeSH
- HeLa buňky MeSH
- heterogenní jaderné ribonukleoproteiny metabolismus MeSH
- jaderné proteiny metabolismus MeSH
- krátké rozptýlené jaderné elementy MeSH
- lidé MeSH
- malý jaderný ribonukleoprotein U1 metabolismus MeSH
- missense mutace * MeSH
- místa sestřihu RNA * MeSH
- proteiny vázající RNA metabolismus MeSH
- represorové proteiny chemie nedostatek metabolismus MeSH
- sekvenční analýza RNA MeSH
- sestřihové faktory chemie nedostatek metabolismus MeSH
- sestřihový faktor U2AF MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
