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1.
Lancet Digit Health ; 6(7): e444, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38906608
2.
EJHaem ; 3(3): 785-793, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36051073

RESUMO

There is sparse evidence of how well haematological targets are met in practice for essential thrombocythemia (ET) and polycythaemia vera (PV) patients. Patient data was collected between 2008 and 2020 from two UK NHS Trusts for ET and PV patients. Longitudinal changes in peripheral blood counts, including the proportion of patients meeting peripheral blood count remission, was modelled. Relative risk of cardiovascular-related events for patients achieving remission within 3-months was estimated. A total of 620 ET and 429 PV patients were analysed. For high-risk patients, haematological parameters decreased in the first months of observation then stabilised within normal reference ranges until year 5. Total time spent in peripheral blood count remission was 39.2% for ET and 29.1% for PV. A lower proportion of ET patients reached target platelet counts (48.3%) compared to WBC (79.1%), whilst PV patients were less likely to reach target haematocrit levels (56.9%) compared to platelets (77.3%) or WBC (74.6%). There was no statistically significant association between reaching target blood counts within 3-months and cardiovascular risk. Complete haematological remission remains a challenging target in managing PV and ET, however this study was unable to show statistically-significant evidence that this was associated with increased risk of cardiovascular events.

3.
J Control Release ; 350: 324-331, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35963468

RESUMO

Faecal microbiota transplant (FMT) is an established and effective treatment for recurrent Clostridioides difficile infection (CDI) and has many other potential clinical applications. However, preparation and quality of FMT is poorly standardised and clinical studies are hampered by a lack of well-defined FMT formulations that meet regulatory standards for medicines. As an alternative to FMT suspensions for administration by nasojejunal tube or colonoscopy, which is invasive and disliked by many patients, this study aimed to develop a well-controlled, standardised method for manufacture of lyophilised FMT capsules and to provide stability data allowing storage for extended time periods. Faecal donations were collected from healthy, pre-screened individuals, homogenised, filtered and centrifuged to remove dietary matter. The suspension was centrifuged to pellet bacteria, which were resuspended with trehalose and lyophilised to produce a powder which was filled into 5 enteric-coated capsules (size 0). Live-dead bacterial cell quantitative PCR assay showed <10 fold viable bacterial load reduction through the manufacturing process. No significant loss of viable bacterial load was observed after storage at -80 °C for 36 weeks (p = 0.24, n = 5). Initial clinical experience demonstrated that the capsules produced clinical cure in patients with CDI with no adverse events reported (n = 7). We provide the first report of a detailed manufacturing protocol and specification for an encapsulated lyophilised formulation of FMT. As clinical trials into intestinal microbiota interventions proceed, it is important to use a well-controlled investigational medicinal product in the studies so that any beneficial results can be replicated in clinical practice.


Assuntos
Clostridioides difficile , Infecções por Clostridium , Microbiota , Infecções por Clostridium/terapia , Fezes , Humanos , Pós , Recidiva , Resultado do Tratamento , Trealose
4.
Expert Opin Drug Deliv ; 16(10): 1081-1094, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31478752

RESUMO

Introduction: Three-dimensional (3D) printing is a relatively new, rapid manufacturing technology that has found promising applications in the drug delivery and medical sectors. Arguably, never before has the healthcare industry experienced such a transformative technology. This review aims to discuss the state of the art of 3D printing technology in healthcare and drug delivery. Areas covered: The current and future applications of printing technologies within drug delivery and medicine have been discussed. The latest innovations in 3D printing of customized medical devices, drug-eluting implants, and printlets (3D-printed tablets) with a tailored dose, shape, size, and release characteristics have been covered. The review also covers the state of the art of 3D printing in healthcare (covering topics such as dentistry, surgical and bioprinting of patient-specific organs), as well as the potential of recent innovations, such as 4D printing, to shape the future of drug delivery and to improve treatment pathways for patients. Expert opinion: A future perspective is provided on the potential for 3D printing in healthcare, covering strategies to overcome the major barriers to integration that are faced today.


Assuntos
Atenção à Saúde/métodos , Sistemas de Liberação de Medicamentos/tendências , Impressão Tridimensional/tendências , Animais , Humanos , Medicina de Precisão , Comprimidos
5.
Drug Discov Today ; 24(2): 417-427, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30453059

RESUMO

It was in 400 BC that Hippocrates reportedly stated that "death sits in the colon". The growth in our knowledge of the intestinal microbiome, the gut-brain axis and their function and imbalance has distinctly uncovered the complex relationship between the gut to disease predisposition and development, heralding the problem and the solution to disease pathology. Human studies of new drug molecules are typically performed in healthy volunteers and their specific disease indication. Approved drugs, however, are used by patients with diverse disease backgrounds. Here, we review the current literature of the gastrointestinal tract reacting to systemic disease pathology that elicits physiological and functional changes that consequently affect oral drug product performance.


Assuntos
Fibrose Cística/metabolismo , Diabetes Mellitus/metabolismo , Trato Gastrointestinal/fisiologia , Infecções por HIV/metabolismo , Absorção Intestinal , Dor/metabolismo , Doença de Parkinson/metabolismo , Animais , Fibrose Cística/fisiopatologia , Diabetes Mellitus/fisiopatologia , Infecções por HIV/fisiopatologia , Humanos , Dor/fisiopatologia , Doença de Parkinson/fisiopatologia , Preparações Farmacêuticas/metabolismo
6.
Int J Pharm ; 548(1): 408-422, 2018 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-29969711

RESUMO

The term "disease" conjures a plethora of graphic imagery for many, and the use of drugs to combat symptoms and treat underlying pathology is at the core of modern medicine. However, the effects of the various gastrointestinal diseases, infections, co-morbidities and the impact of gastrointestinal surgery on the pharmacokinetic and pharmacodynamic behaviour of drugs have been largely overlooked. The better elucidation of disease pathology and the role of underlying cellular and molecular mechanisms have increased our knowledge as far as diagnoses and prognoses are concerned. In addition, the recent advances in our understanding of the intestinal microbiome have linked the composition and function of gut microbiota to disease predisposition and development. This knowledge, however, applies less so in the context of drug absorption and distribution for orally administered dosage forms. Here, we revisit and re-evaluate the influence of a portfolio of gastrointestinal diseases and surgical effects on the functionality of the gastrointestinal tract, their implications for drug delivery and attempt to uncover significant links for clinical practice.


Assuntos
Gastroenteropatias/metabolismo , Absorção Intestinal , Administração Oral , Cirurgia Bariátrica , Gastroenteropatias/tratamento farmacológico , Humanos , Infecções/tratamento farmacológico , Infecções/metabolismo , Preparações Farmacêuticas/administração & dosagem
7.
Int J Pharm ; 496(2): 414-20, 2015 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-26481468

RESUMO

The aim of this work was to explore the feasibility of using fused deposition modelling (FDM) 3D printing (3DP) technology with hot melt extrusion (HME) and fluid bed coating to fabricate modified-release budesonide dosage forms. Budesonide was sucessfully loaded into polyvinyl alcohol filaments using HME. The filaments were engineered into capsule-shaped tablets (caplets) containing 9mg budesonide using a FDM 3D printer; the caplets were then overcoated with a layer of enteric polymer. The final printed formulation was tested in a dynamic dissolution bicarbonate buffer system, and two commercial budesonide products, Cortiment® (Uceris®) and Entocort®, were also investigated for comparison. Budesonide release from the Entocort® formulation was rapid in conditions of the upper small intestine while release from the Cortiment® product was more delayed and very slow. In contrast, the new 3D printed caplet formulation started to release in the mid-small intestine but release then continued in a sustained manner throughout the distal intestine and colon. This work has demonstrated the potential of combining FDM 3DP with established pharmaceutical processes, including HME and film coating, to fabricate modified release oral dosage forms.


Assuntos
Budesonida/administração & dosagem , Impressão Tridimensional , Tecnologia Farmacêutica/métodos , Budesonida/química , Preparações de Ação Retardada , Solubilidade , Comprimidos
8.
Int J Pharm ; 484(1-2): 103-8, 2015 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-25721685

RESUMO

The aminosalicylate mesalazine (mesalamine) forms the mainstay of treatment in ulcerative colitis (UC), a disease for which many commercial modified-release products have been developed with the aim of providing targeted gastrointestinal release. The release profiles of five of these commercial formulations were evaluated in bicarbonate buffer using a novel dissolution model that mimics the dynamic conditions of the gastrointestinal tract. Monolithic and multi-particulate mesalazine formulations with pH-dependent and/or independent release mechanisms were evaluated (Asacol(®) 800, Octasa(®), Mezavant(®) XL, Salofalk(®), Pentasa(®)), and each of the products displayed a distinctive dissolution profile. The dissolution results for Mezavant(®) XL (Lialda(®)) (lag time 290 min) demonstrated good correlation with previously reported in vivo disintegration times assessed by gamma-scintigraphy in humans. Octasa(®) showed a similar lag time to Mezavant(®) XL. Drug release from Asacol(®) 800 (Asacol(®) HD) showed a wide standard deviation, reflecting the great variability in vivo. Salofalk(®) displayed both delayed release and extended release characteristics. Pentasa(®) released more than 50% of its drug load in the stomach compartment of the model, which is attributed to the absence of a gastro-resistant coating in this product. The new dissolution method provided a realistic and discriminative in vitro assessment of mesalazine release from different formulations. These results demonstrate that this strategy can be used to predict intestinal release behaviour, and potentially aid the rational design of products developed to target different sites of the gut.


Assuntos
Liberação Controlada de Fármacos , Trato Gastrointestinal , Mesalamina/química , Mesalamina/farmacocinética , Química Farmacêutica , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/metabolismo , Humanos , Solubilidade
9.
J Pharm Sci ; 104(9): 2747-76, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25712759

RESUMO

"All animals are equal, but some are more equal than others" was the illustrious quote derived from British writer George Orwell's famed work, Animal Farm. Extending beyond the remit of political allegory, however, this statement would appear to hold true for the selection of appropriate animal models to simulate human physiology in preclinical studies. There remain definite gaps in our current knowledge with respect to animal physiology, notably those of intra- and inter-species differences in gastrointestinal (GI) function, which may affect oral drug delivery and absorption. Factors such as cost and availability have often influenced the choice of animal species without clear justification for their similarity to humans, and lack of standardization in techniques employed in past studies using various animals may also have contributed to the generation of contradictory results. As it stands, attempts to identify a single animal species as appropriately representative of human physiology and which may able to adequately simulate human in vivo conditions are limited. In this review, we have compiled and critically reviewed data from numerous studies of GI anatomy and physiology of various animal species commonly used in drug delivery modeling, commenting on the appropriateness of these animals for in vivo comparison and extrapolation to humans.


Assuntos
Sistemas de Liberação de Medicamentos , Trato Gastrointestinal/fisiologia , Modelos Animais , Animais , Humanos , Absorção Intestinal/fisiologia , Especificidade da Espécie
10.
Eur J Pharm Biopharm ; 89: 157-62, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25497178

RESUMO

The aim of this study was to explore the potential of fused-deposition 3-dimensional printing (FDM 3DP) to produce modified-release drug loaded tablets. Two aminosalicylate isomers used in the treatment of inflammatory bowel disease (IBD), 5-aminosalicylic acid (5-ASA, mesalazine) and 4-aminosalicylic acid (4-ASA), were selected as model drugs. Commercially produced polyvinyl alcohol (PVA) filaments were loaded with the drugs in an ethanolic drug solution. A final drug-loading of 0.06% w/w and 0.25% w/w was achieved for the 5-ASA and 4-ASA strands, respectively. 10.5mm diameter tablets of both PVA/4-ASA and PVA/5-ASA were subsequently printed using an FDM 3D printer, and varying the weight and densities of the printed tablets was achieved by selecting the infill percentage in the printer software. The tablets were mechanically strong, and the FDM 3D printing was shown to be an effective process for the manufacture of the drug, 5-ASA. Significant thermal degradation of the active 4-ASA (50%) occurred during printing, however, indicating that the method may not be appropriate for drugs when printing at high temperatures exceeding those of the degradation point. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) of the formulated blends confirmed these findings while highlighting the potential of thermal analytical techniques to anticipate drug degradation issues in the 3D printing process. The results of the dissolution tests conducted in modified Hank's bicarbonate buffer showed that release profiles for both drugs were dependent on both the drug itself and on the infill percentage of the tablet. Our work here demonstrates the potential role of FDM 3DP as an efficient and low-cost alternative method of manufacturing individually tailored oral drug dosage, and also for production of modified-release formulations.


Assuntos
Ácido Aminossalicílico/química , Mesalamina/química , Comprimidos/química , Tecnologia Farmacêutica/métodos , Varredura Diferencial de Calorimetria/métodos , Química Farmacêutica/métodos , Temperatura Alta , Soluções Farmacêuticas/química , Álcool de Polivinil/química , Impressão Tridimensional
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