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1.
Pharmaceutics ; 16(8)2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39204432

RESUMO

Neratinib maleate (NM), a tyrosine kinase inhibitor, is used in the treatment of breast cancer. NM is orally administered at a high dose of 290 mg due to its low solubility and poor dissolution rate at pH > 3, as well as gut-wall metabolism limiting its bioavailability. Self-emulsifying drug delivery systems (SEDDSs) of NM were developed in the current study to improve its oral bioavailability. The oily vehicle (clove oil) was selected based on the solubility of NM, while the surfactant and the cosurfactant were selected based on the turbidimetric analysis. Three different sets were screened for surfactant selection in the preparation of SEDDS formulations, the first set containing Cremophor® EL alone as the surfactant, the second set containing a mixture of Cremophor® EL (surfactant) and Caproyl® PGMC (cosurfactant), and the third set containing a mixture of Cremophor® EL (surfactant) and Capmul® MCM C8 (cosurfactant). Propylene glycol was used as the cosolubilizer in the preparation of SEDDSs. A series of studies, including the construction of ternary phase diagrams to determine the zone of emulsification, thermodynamic stability studies (involving dilution studies, freeze-thaw, and heating-cooling studies), turbidimetric analysis, and physicochemical characterization studies were conducted to identify the two most stable combinations of SEDDSs. The two optimized SEDDS formulations, TP16 and TP25, consisted of clove oil (45% w/w) and propylene glycol (5% w/w) in common but differed with respect to the surfactant or surfactant mixture in the formulations. TP16 was prepared using a mixture of Cremophor® EL (surfactant) and Caproyl® PGMC (cosurfactant) in a 4:1 ratio (50% w/w), while TP25 contained only Cremophor® EL (50% w/w). The mean globule sizes were 239.8 ± 77.8 nm and 204.8 ± 2.4 nm for TP16 and TP25, respectively, with an emulsification time of <12 s for both formulations. In vitro drug dissolution studies performed at different pH conditions (3.0, 4.5, 6.8) have confirmed the increase in solubility and dissolution rate of the drug by TP16 and TP25 at all pH conditions compared to plain NM. An oral pharmacokinetic study in female Wistar rats showed that the relative bioavailability (Frel) values of TP16 and TP25 over the plain NM were 2.18 (p < 0.05) and 2.24 (p < 0.01), respectively.

2.
Nanomaterials (Basel) ; 14(16)2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39195385

RESUMO

Nebivolol hydrochloride (NEB), a 3rd-generation beta-blocker, was recently explored in managing open-angle glaucoma due to its mechanism of action involving nitric oxide release for the vasodilation. To overcome the issue of low ocular bioavailability and the systemic side effects associated with conventional ocular formulation (aqueous suspension), we designed and optimized polycaprolactone polymeric nanoparticles (NEB-PNPs) by applying design of experiments (DoE). The particle size and drug loading of the optimized NEB-PNPs were 270.9 ± 6.3 nm and 28.8 ± 2.4%, respectively. The optimized NEB-PNPs were suspended in a dual-sensitive in situ gel prepared using a mixture of P407 + P188 (as a thermo-sensitive polymer) and κCRG (as an ion-sensitive polymer), reported previously by our group. The NEB-PNPs-loaded in situ gel (NEB-PNPs-ISG) formulation was characterized for its rheological behavior, physical and chemical stability, in vitro drug release, and in vivo efficacy. The NEB-PNPs-loaded in situ gel, in ocular pharmacokinetic studies, achieved higher aqueous humor exposure (AUC0-t = 329.2 ng × h/mL) and for longer duration (mean residence time = 9.7 h) than compared to the aqueous suspension of plain NEB (AUC0-t = 189 ng × h/mL and mean residence time = 6.1 h) reported from our previous work. The pharmacokinetic performance of NEB-PNPs-loaded in situ gel translated into a pharmacodynamic response with 5-fold increase in the overall percent reduction in intraocular pressure by the formulation compared to the aqueous suspension of plain NEB reported from our previous work. Further, the mean response time of NEB-PNPs-loaded in situ gel (12.4 ± 0.6 h) was three times higher than aqueous suspension of plain NEB (4.06 ± 0.3 h).

3.
J Med Genet ; 61(5): 477-482, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38124008

RESUMO

OBJECTIVE: The purpose of this study was to recontact individuals with clinically actionable test results identified through a retrospective research study and to provide a framework for laboratories to recontact patients. METHODS: Genetic testing was conducted on 2977 individuals originally referred for BRCA1 and BRCA2 hereditary breast and ovarian cancer testing that had a negative genetic test result. A gene panel was used to identify pathogenic variants in known or newly discovered genes that could explain the underlying cause of disease; however, analysis was restricted to PALB2 for the purposes of this study. A patient recontact decision tree was developed to assist in the returning of updated genetic test results to clinics and patients. RESULTS: Novel clinically actionable pathogenic variants were identified in the PALB2 gene in 18 participants (0.6%), the majority of whom were recontacted with their new or updated genetic test results. Eight individuals were unable to be recontacted; five individuals had already learnt about their new or updated findings from genetic testing outside the context of this study; three individuals prompted cascade testing in family members; two individuals were deceased. CONCLUSION: Novel pathogenic variants in PALB2 were identified in 18 individuals through retrospective gene panel testing. Recontacting these individuals regarding these new or updated findings had a range of outcomes. The process of conveying genomic results within this framework can be effectively accomplished while upholding patient autonomy, potentially leading to advantageous outcomes for patients and their families.


Assuntos
Dever de Recontatar , Proteína do Grupo de Complementação N da Anemia de Fanconi , Laboratórios Clínicos , Feminino , Humanos , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/genética , Proteína do Grupo de Complementação N da Anemia de Fanconi/genética , Predisposição Genética para Doença , Testes Genéticos , Estudos Retrospectivos
4.
Biomed Chromatogr ; 37(11): e5731, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37651999

RESUMO

The current research work reports the development and validation of a sensitive, robust and reproducible bioanalytical method for quantifying neratinib maleate in rat plasma. More than 85% of the drug was extracted from the plasma samples by protein precipitation. The method was optimized using Box-Behnken design, a response surface method. The effect of three critical factors, viz., the pH of the buffer (X1 ), the aqueous phase proportion in the mobile phase (X2 ) and the mobile phase flow rate (X3 ), was studied on two response variables, retention time (Y1 ) and United States Pharmacopoeia (USP) width (Y2 ). With the highest overall desirability function value of 0.943, the obtained optimized method conditions were: X1  = 2.4 ± 0.1; X2  = 66.7 ml, and X3  = 0.85 ml/min. Under the optimized conditions, the values of Y1 and Y2 for a sample containing 1 ppm of the drug were found to be 14.1 min and 0.50 ± 0.003, respectively. Single-dose intravenous bolus (7.5 mg/kg) and oral (15 mg/kg) pharmacokinetic studies were performed to determine the absolute bioavailability of the drug. The optimized bioanalytical method was sensitive enough to capture 95% of the drug eliminated from the body. The absolute oral bioavailability of the drug was 49.30%.

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