RESUMO
The anticancer drug paclitaxel is formulated for i.v. administration in a mixture of Cremophor EL and ethanol.Its oral bioavailability is very low due to the action of P-glycoproteinin the gut wall and CYP450 in gut wall and liver.However, proof-of-concept studies using the i.v. formulation diluted in drinking water have demonstrated the feasibility of the oral route as an alternative when given in combination with inhibitors of P-glycoprotein and CYP450. Because of the unacceptable pharmaceutical properties of the drinking solution, a better formulation for oral application is needed.We have evaluated the suitability of various self-micro emulsifying oily formulations (SMEOF's) of paclitaxel for oral application using wild-type and P-glycoprotein knockout mice and cyclosporin A (CsA) as P-glycoprotein and CYP450 inhibitor. The oral bioavailability of paclitaxel in all SMEOF's without concomitant CsA was low in wild-type mice, showing that this vehicle does not enhance intestinal uptake by itself.Paclitaxel (10 mg/kg) in SMEOF#3 given with CsA resulted in plasma levels that were comparable to the Cremophor ELethanol containing drinking solution plus CsA. Whereas the AUC increased linearly with the oral paclitaxel dose in P-glycoprotein knockout mice, it increased less than proportional in wild-type mice given with CsA. In both strains more unchanged paclitaxel was recovered in the feces at higher doses. This observation most likely reflects more profound precipitation of paclitaxel within the gastro-intestinal tract at higher doses. The resulting absolute reduction in absorption of paclitaxel from the gut was possibly concealed by partial saturation of first-pass metabolism when P-glycoprotein was absent. In conclusion, SMEOF's maybe a useful vehicle for oral delivery of paclitaxel in combination with CsA, although the physical stability within the gastro-intestinal tract remains a critical issue, especially when applied at higher dose levels.
Assuntos
Emulsões/química , Paclitaxel/farmacocinética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/deficiência , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Administração Oral , Animais , Disponibilidade Biológica , Química Farmacêutica , Fezes , Feminino , Camundongos , Camundongos Knockout , Paclitaxel/administração & dosagem , Paclitaxel/sangue , Fatores de TempoRESUMO
PURPOSE: The aim of this study was to characterize the expression of inflammation-related genes on the ocular surface of Sjögren syndrome (SS) patients and to evaluate their correlations with clinical symptoms and signs. METHODS: The study enrolled 30 patients with SS dry eye and 15 healthy controls. Symptoms were evaluated using OSDI questionnaire. The clinical signs were investigated using corneal fluorescein staining (CFS), tear breakup time (TBUT), Schirmer test and tear osmolarity measurement. Conjunctival superficial cells were collected using conjunctival impression cytology and total RNAs were extracted for analysis using the NanoString® nCounter technology. The Mann-Whitney nonparametric statistical test and Spearman correlations were used to explore the correlations between the up/downregulated genes and the clinical signs and symptoms. RESULTS: Twenty-seven genes were upregulated and 13 were downregulated with statistically significant fold changes ranging from 1.5 to 16.7 and 0.3 to 0.8, respectively. OSDI and CFS were the most significantly correlated parameters with 21 and 19 inflammatory genes, respectively. Among all the upregulated genes, 14 were positively correlated with both OSDI and CFS. Two downregulated genes (GNGT1, HSPB2) were negatively correlated with OSDI and CFS. IL1RN was the only gene positively correlated with the Schirmer test. CONCLUSIONS: These results highlight the differentially expressed genes in primary Sjögren syndrome and their relationships between the inflammatory genes expressed and the patient symptom score and corneal damage. The inflammatory genes implicated in SS-associated dry eye could be important tools to determine the pathophysiological profiles of SS and potentially useable as specific signatures.
Assuntos
Túnica Conjuntiva/metabolismo , Citocinas/genética , Síndromes do Olho Seco/genética , Regulação da Expressão Gênica , RNA/genética , Síndrome de Sjogren/genética , Lágrimas/metabolismo , Adulto , Biópsia , Túnica Conjuntiva/patologia , Estudos Transversais , Citocinas/biossíntese , Síndromes do Olho Seco/diagnóstico , Síndromes do Olho Seco/metabolismo , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , RNA/metabolismo , Síndrome de Sjogren/diagnóstico , Síndrome de Sjogren/metabolismoRESUMO
OBJECTIVE: To assess medical practices surrounding the use of topical ocular cyclosporine A across European Union nations. METHODS: Key stakeholders (ophthalmologists, hospital pharmacists, regulatory health authorities) from European Union member states were interviewed by telephone using a semi-structured, open-ended questionnaire. Ophthalmologists responded to questions about practice patterns of cyclosporine A use (prescription frequency, indication, dosage), pharmacists about cyclosporine A formulations (composition, manufacturing process, quality control, distribution), and the regulatory authorities about market authorization and pharmacovigilance for various cyclosporine A products. RESULTS: Over the years, cyclosporine A use for ophthalmic indications has increased across all European Union nations. Prevalence of cyclosporine A use was heterogeneous, with Belgium, France, Germany, Italy, Portugal, Spain and the United Kingdom reporting the highest frequency. Compounded cyclosporine A formulations and other cyclosporine A products were prescribed through temporary authorization on a compassionate use or named-patient basis. Cyclosporine A was prescribed for dry eye disease, atopic and vernal keratoconjunctivitis, corneal graft rejection, and other autoimmune and inflammatory diseases. Concentrations of prescribed topical cyclosporine A ranged between 0.05-2% and formulations were instilled 1-6 times daily. Interviewed stakeholders expressed concern regarding, (1) paucity of product information, (2) lack of standardized manufacturing processes and quality control of cyclosporine A formulations, and (3) poor regulation and pharmacovigilance of ocular cyclosporine A-based products. CONCLUSIONS: Medical practice surrounding ocular cyclosporine A use in European Union nations differs based on variations in concentration, dosage, prescription indication, formulation, availability and distribution, manufacturing, quality, and regulatory monitoring.
Assuntos
Ciclosporina/administração & dosagem , União Europeia/estatística & dados numéricos , Soluções Oftálmicas/administração & dosagem , Padrões de Prática Médica/estatística & dados numéricos , Administração Tópica , Ciclosporina/efeitos adversos , Europa (Continente)/epidemiologia , Oftalmopatias/tratamento farmacológico , Oftalmopatias/epidemiologia , Humanos , Soluções Oftálmicas/efeitos adversos , Farmacovigilância , Inquéritos e QuestionáriosRESUMO
PURPOSE: The purpose of this study was to compare the safety and efficacy of a new cationic emulsion (CE) with a formulation of polyvinyl alcohol and povidone (PVA-P) for the treatment of mild to moderate dry eye disease. METHODS: This was a multicenter, open-label, comparative study. Patients were randomised to receive CE (Cationorm) or PVA-P (Refresh) (1:1). The following objective criteria were assessed to compare the two eye drops: tear Break-up Time (TBUT), Schirmer's test, lissamine green staining (Van Bijsterveld score), corneal fluorescein staining (Oxford scale) and oculopalpebral examination, on D7 and D28 (end of study). At these visits, ocular symptoms and safety were also assessed. RESULTS: Seventy-nine patients were randomised: CE: 44 patients; PVA-P: 35 patients. At D28, improvement was significantly better for TBUT [CE: 1.7 ± 2.4 s; PVA-P: 0.6 ± 1.8 s; P=0.015] and for the Van Bijsterveld score [CE: -1.4 ± 1.2; PVA-P: -0.9 ± 1.2; P=0.046] in the CE group. The same applied for the palpebral erythema score (P=0.023), overall efficacy assessed by the investigators (P<0.001), and symptoms not related to eye drop instillation (P=0.021). Improvement was observed from D7. No difference was observed between the two treatments with regard to ocular safety. CONCLUSION: These results suggest that in patients with mild to moderate dry eye, Cationorm, in addition to its moisturizing and lubricating properties, also helps stabilize the tear film due to its oily component. This study demonstrates the benefit of this new pharmaceutical form for the treatment of mild to moderate dry eye disease.
Assuntos
Síndromes do Olho Seco/tratamento farmacológico , Soluções Oftálmicas/uso terapêutico , Administração Oftálmica , Idoso , Combinação de Medicamentos , Emulsões/administração & dosagem , Emulsões/efeitos adversos , Emulsões/farmacologia , Emulsões/uso terapêutico , Feminino , Fluoresceína , Humanos , Corantes Verde de Lissamina , Masculino , Pessoa de Meia-Idade , Soluções Oftálmicas/administração & dosagem , Soluções Oftálmicas/efeitos adversos , Soluções Oftálmicas/farmacologia , Álcool de Polivinil/administração & dosagem , Álcool de Polivinil/efeitos adversos , Álcool de Polivinil/farmacologia , Álcool de Polivinil/uso terapêutico , Povidona/administração & dosagem , Povidona/efeitos adversos , Povidona/farmacologia , Povidona/uso terapêutico , Índice de Gravidade de Doença , Lágrimas/efeitos dos fármacos , Resultado do TratamentoRESUMO
To explore the parmacokinetics, safety and tolerability of paclitaxel after oral administration of SMEOF#3, a novel Self-Microemulsifying Oily Formulation, in combination with cyclosporin A (CsA) in patients with advanced cancer. Seven patients were enrolled and randomly assigned to receive oral paclitaxel (SMEOF#3) 160 mg+CsA 700 mg on day 1, followed by oral paclitaxel (Taxol) 160 mg+CsA 700 mg on day 8 (group I) or vice versa (group II). Patients received paclitaxel (Taxol) 160 mg as 3-h infusion on day 15. The median (range) area under the plasma concentration-time curve of paclitaxel was 2.06 (1.15-3.47) microg h ml(-1) and 1.97 (0.58-3.22) microg h ml(-1) after oral administration of SMEOF#3 and Taxol, respectively, and 4.69 (3.90-6.09) microg h ml(-1) after intravenous Taxol. Oral SMEOF#3 resulted in a lower median T(max) of 2.0 (0.5-2.0) h than orally applied Taxol (T(max)=4.0 (0.8-6.1) h, P=0.02). The median apparent bioavailability of paclitaxel was 40 (19-83)% and 55 (9-70)% for the oral SMEOF#3 and oral Taxol formulation, respectively. Oral paclitaxel administered as SMEOF#3 or Taxol was safe and well tolerated by the patients. Remarkably, the SMEOF#3 formulation resulted in a significantly lower T(max) than orally applied Taxol, probably due to the excipients in the SMEOF#3 formulation resulting in a higher absorption rate of paclitaxel.