scholarly journals Advanced Formulation Approaches for Ocular Drug Delivery: State-Of-The-Art and Recent Patents

Pharmaceutics ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 460 ◽  
Author(s):  
Eliana B. Souto ◽  
João Dias-Ferreira ◽  
Ana López-Machado ◽  
Miren Ettcheto ◽  
Amanda Cano ◽  
...  

The eye presents extensive perspectives and challenges for drug delivery, mainly because of the extraordinary capacity, intrinsic to this path, for drugs to permeate into the main circulatory system and also for the restrictions of the ocular barriers. Depending on the target segment of the eye, anterior or posterior, the specifications are different. The ocular route experienced in the last decades a lot of progresses related with the development of new drugs, improved formulations, specific-designed delivery and even new routes to administer a drug. Concomitantly, new categories of materials were developed and adapted to encapsulate drugs. With such advances, a multiplicity of parameters became possible to be optimized as the increase in bioavailability and decreased toxic effects of medicines. Also, the formulations were capable to easily adhere to specific tissues, increase the duration of the therapeutic effect and even target the delivery of the treatment. The ascending of new delivery systems for ocular targeting is a current focus, mainly because of the capacity to extend the normal time during which the drug exerts its therapeutic effect and, so, supplying the patients with a product which gives them fewer side effects, fewer number of applications and even more effective outcomes to their pathologies, surpassing the traditionally-used eye drops. Depending on the systems, some are capable of increasing the duration of the drug action as gels, emulsions, prodrugs, liposomes, and ocular inserts with hydrophilic properties, improving the absorption by the cornea. In parallel, other devices use as a strategy the capacity to sustain the release of the carried drugs by means of erodible and non-erodible matrices. This review discusses the different types of advanced formulations used for ocular delivery of therapeutics presenting the most recent patents according to the clinical applications.

2021 ◽  
Vol 7 ◽  
Author(s):  
Offer Zeira ◽  
Erica Ghezzi ◽  
Letizia Pettinari ◽  
Valentina Re ◽  
Davide M. Lupi ◽  
...  

Mesothelioma is a rare lethal tumor of dogs and humans involving cavities of the body. Dogs are considered a model for new drugs and therapeutic methods since they present spontaneous diseases similar to humans. Microfragmented adipose tissue (MFAT) uploaded by paclitaxel (PTX) is a drug delivery medium providing slow release of chemotherapic drugs. A dog affected by pleural, pericardial, and peritoneal mesothelioma was treated by 17 intracavitary ultrasound-guided injections of MFAT-PTX over 22 months. A long-lasting improvement of general conditions was observed, treatment was well-tolerated, and no toxicity or hypersensitivity was reported. Pharmacokinetic (PK) data indicated low drug localization in the circulatory system and a tendency to enter or remain in the extravascular compartments of the body. Indeed, low levels of free-circulating drugs for a short time produced low toxicity, whereas, a higher intracavitary PTX concentration can have major pharmacological efficacy. To our knowledge, this is the first time that mesothelioma has been treated using such a procedure, and this should be considered as a novel therapeutic approach. The low systemic absorption suggests the possible role of MFAT-PTX for loco-regional/intratumoral therapy also useful in other types of tumors, and further investigation is warranted.


Author(s):  
Neeraj Singh ◽  
Shweta Rai ◽  
Sankha Bhattacharya

Background: About two-third of new drugs reveal low solubility in water due to that; it becomes difficult for formulation scientists to develop oral solid dosage forms with a pharmaceutically acceptable range of therapeutic activity. In such cases, S-SMEEDS are the best carrier used universally for the delivery of hydrophobic drugs. SEDDS were also used, but due to its limitations, S-SMEDDS used widely. These are the isotropic mixtures of oils, co-solvents, and surfactants. S-SMEDDS are physically stable, easy to manufacture, easy to fill in gelatin capsules as well as improves the drug bioavailability by releasing the drug in the emulsion form to the gastrointestinal tract and make smooth absorption of the drug through the intestinal lymphatic pathway. Methods: We took on the various literature search related to our review, including the peer-reviewed research, and provided a conceptual framework to that. Standard tools are used for making the figures of the paper, and various search engines are used for the literature exploration.In this review article the author discussed the importance of S-SMEDDS, selection criteria for excipients, pseudo-ternary diagram, mechanism of action of S-SMEDDS, solidification techniques used for S-SMEDDS, Characterization of SEDDS and S-SMEDDS including Stability Evaluation of both and future prospect concluded through recent findings on S-SMEDDS on Cancer as well as a neoteric patent on S-SMEDDS Results: Many research papers discussed in this review article, from which it was found that the ternary phase diagram is the most crucial part of developing the SMEDDS. From the various research findings, it was found that the excipient selection is the essential step which decides the strong therapeutic effect of the formulation. The significant outcome related to solid-SMEDDS is less the globule size, higher would be the bioavailability. The adsorption of a solid carrier method is the most widely used method for the preparation of solid-SMEDDS. After review of many patents, it is observed that the solid-SMEDDS have a strong potential for targeting and treatment of a different type of Cancer due to their property to enhance permeation and increased bioavailability. Conclusion: S-SMEEDS are more acceptable pharmaceutically as compare to SEDDS due to various advantages over SEDDS viz stability issue is prevalent with SEDDS. A number of researchers had formulated S-SMEDDS of poorly soluble drugs and founded S-SMEDDS as prospective for the delivery of hydrophobic drugs for the treatment of Cancer. S-SMEEDS are grabbing attention, and the patentability on S-SMEDDS is unavoidable, these prove that S-SMEEDS are widely accepted carriers. These are used universally for the delivery of the hydrophilic drugs and anticancer drugs as it releases the drug to the gastrointestinal tract and enhances the systemic absorption. Abstract: Majority of active pharmaceutical ingredients (API) shows poor aqueous solubility, due to that drug delivery of the API to the systemic circulation becomes difficult as it has low bioavailability. The bioavailability of the hydrophobic drugs can be improved by the Self-emulsifying drug delivery system (SEDDS) but due to its various limitations, solid self-micro emulsifying drug delivery systems (S-SMEDDS) are used due to its advantages over SEDDS. S-SMEDDS plays a vital role in improving the low bioavailability of poorly aqueous soluble drugs. Hydrophobic drugs can be easily loaded in these systems and release the drug to the gastrointestinal tract in the form of fine emulsion results to In-situ solubilisation of the drug. In this review article the author's gives an overview of the solid SMEDSS along with the solidification techniques and an update on recent research and patents filled for Solid SMEDDS.


2020 ◽  
Vol 10 ◽  
Author(s):  
Sapna Saini ◽  
Sanju Nanda ◽  
Anju Dhiman

: Chitosan, a natural biodegradable polymer obtained from deacetylation of chitin, has been used as an approbative macromolecule for the development of various novel drug delivery systems. It is one of the most favorable biodegradable carriers for nanoparticulate drug delivery due to its intrinsic properties, such as biocompatibility, biodegradability, non-toxicity, availability of free reactive amino groups, and ease of chemical modification into different active derivatives. Furthermore, interesting physical properties (film-forming, gelling and thickening) make it a suitable candidate for formulations, such as films, microcapsules, beads, nanoparticles, nanofibres, nanogel and so on. Researchers have reported that chitosan nanoparticles act as a promising vehicle for herbal actives as they provide a superior alternative to traditional carriers and improve pharmaceutical efficiency. As no review of chitosan nanoparticles encapsulating herbal extracts and bioactives has been published till date, a maiden effort has been made to collate and review the use of chitosan nanoparticles for the entrapment of phytoconstituents to yield stable, efficient and safe drug delivery systems. Additionally, the paper presents a comprehensive account of the state-of the-art in fabricating herbal chitosan nanoparticles and their current pharmacological status. A list of patents on chitosan nanoparticles of herbal actives has also been included. This review is intended to serve as a didactic discourse for the formulation scientists endeavoring to develop advanced delivery systems for herbal actives.


2021 ◽  
Vol 13 ◽  
pp. 251584142110127
Author(s):  
Preeya K. Gupta ◽  
Nandini Venkateswaran

The tear film, which includes mucins that adhere to foreign particles, rapidly clears allergens and pathogens from the ocular surface, protecting the underlying tissues. However, the tear film’s ability to efficiently remove foreign particles during blinking can also pose challenges for topical drug delivery, as traditional eye drops (solutions and suspensions) are cleared from the ocular surface before the drug can penetrate into the conjunctival and corneal epithelium. In the past 15 years, there has been an increase in the development of nanoparticles with specialized coatings that have reduced affinity to mucins and are small enough in size to pass through the mucus barrier. These mucus-penetrating particles (MPPs) have been shown to efficiently penetrate the mucus barrier and reach the ocular surface tissues. Dry eye disease (DED) is a common inflammatory ocular surface disorder that often presents with periodic flares (exacerbations). However, currently approved immunomodulatory treatments for DED are intended for long-term use. Thus, there is a need for effective short-term treatments that can address intermittent flares of DED. Loteprednol etabonate, an ocular corticosteroid, was engineered to break down rapidly after administration to the ocular surface tissues and thereby reduce risks associated with other topical steroids. KPI-121 is an ophthalmic suspension that uses the MPP technology to deliver loteprednol etabonate more efficiently to the ocular tissues, achieving in animal models a 3.6-fold greater penetration of loteprednol etabonate to the cornea than traditional loteprednol etabonate ophthalmic suspensions. In clinical trials, short-term treatment with KPI-121 0.25% significantly reduced signs and symptoms of DED compared with its vehicle (placebo). Recently approved KPI-121 0.25%, with its novel drug delivery design and ease of use, has the potential to effectively treat periodic flares of DED experienced by many patients.


Author(s):  
Wei Huang ◽  
Xiaoshu Zhou ◽  
Mingchao Dong ◽  
Huaiyu Xu

AbstractRobust and high-performance visual multi-object tracking is a big challenge in computer vision, especially in a drone scenario. In this paper, an online Multi-Object Tracking (MOT) approach in the UAV system is proposed to handle small target detections and class imbalance challenges, which integrates the merits of deep high-resolution representation network and data association method in a unified framework. Specifically, while applying tracking-by-detection architecture to our tracking framework, a Hierarchical Deep High-resolution network (HDHNet) is proposed, which encourages the model to handle different types and scales of targets, and extract more effective and comprehensive features during online learning. After that, the extracted features are fed into different prediction networks for interesting targets recognition. Besides, an adjustable fusion loss function is proposed by combining focal loss and GIoU loss to solve the problems of class imbalance and hard samples. During the tracking process, these detection results are applied to an improved DeepSORT MOT algorithm in each frame, which is available to make full use of the target appearance features to match one by one on a practical basis. The experimental results on the VisDrone2019 MOT benchmark show that the proposed UAV MOT system achieves the highest accuracy and the best robustness compared with state-of-the-art methods.


Minerals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 235
Author(s):  
Nicolò Maria Ippolito ◽  
Ionela Birloaga ◽  
Francesco Ferella ◽  
Marcello Centofanti ◽  
Francesco Vegliò

The present paper is focused on the extraction of gold from high-grade e-waste, i.e., spent electronic connectors and plates, by leaching and electrowinning. These connectors are usually made up of an alloy covered by a layer of gold; sometimes, in some of them, a plastic part is also present. The applied leaching system consisted of an acid solution of diluted sulfuric acid (0.2 mol/L) with thiourea (20 g/L) as a reagent and ferric sulfate (21.8 g/L) as an oxidant. This system was applied on three different high-grade e-waste, namely: (1) Connectors with the partial gold-plated surface (Au concentration—1139 mg/kg); (2) different types of connectors with some of which with completely gold-plated surface (Au concentration—590 mg/kg); and (3) connectors and plates with the completely gold-plated surface (Au concentration—7900 mg/kg). Gold dissolution yields of 52, 94, and 49% were achieved from the first, second, and third samples, respectively. About 95% of Au recovery was achieved after 1.5 h of electrowinning at a current efficiency of only 4.06% and current consumption of 3.02 kWh/kg of Au from the leach solution of the third sample.


AI ◽  
2021 ◽  
Vol 2 (2) ◽  
pp. 261-273
Author(s):  
Mario Manzo ◽  
Simone Pellino

COVID-19 has been a great challenge for humanity since the year 2020. The whole world has made a huge effort to find an effective vaccine in order to save those not yet infected. The alternative solution is early diagnosis, carried out through real-time polymerase chain reaction (RT-PCR) tests or thorax Computer Tomography (CT) scan images. Deep learning algorithms, specifically convolutional neural networks, represent a methodology for image analysis. They optimize the classification design task, which is essential for an automatic approach with different types of images, including medical. In this paper, we adopt a pretrained deep convolutional neural network architecture in order to diagnose COVID-19 disease from CT images. Our idea is inspired by what the whole of humanity is achieving, as the set of multiple contributions is better than any single one for the fight against the pandemic. First, we adapt, and subsequently retrain for our assumption, some neural architectures that have been adopted in other application domains. Secondly, we combine the knowledge extracted from images by the neural architectures in an ensemble classification context. Our experimental phase is performed on a CT image dataset, and the results obtained show the effectiveness of the proposed approach with respect to the state-of-the-art competitors.


Cancers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 691
Author(s):  
Milana Bergamino Sirvén ◽  
Sonia Pernas ◽  
Maggie C. U. Cheang

The rapidly evolving landscape of immuno-oncology (IO) is redefining the treatment of a number of cancer types. IO treatments are becoming increasingly complex, with different types of drugs emerging beyond checkpoint inhibitors. However, many of the new drugs either do not progress from phase I-II clinical trials or even fail in late-phase trials. We have identified at least five areas in the development of promising IO treatments that should be redefined for more efficient designs and accelerated approvals. Here we review those critical aspects of IO drug development that could be optimized for more successful outcome rates in all cancer types. It is important to focus our efforts on the mechanisms of action, types of response and adverse events of these novel agents. The use of appropriate clinical trial designs with robust biomarkers of response and surrogate endpoints will undoubtedly facilitate the development and subsequent approval of these drugs. Further research is also needed to establish biomarker-driven strategies to select which patients may benefit from immunotherapy and identify potential mechanisms of resistance.


2021 ◽  
Vol 13 ◽  
pp. 175883592098765
Author(s):  
Vincenza Conteduca ◽  
Giulia Poti ◽  
Paola Caroli ◽  
Sabino Russi ◽  
Nicole Brighi ◽  
...  

Over the years, an increasing proportion of metastatic prostate cancer patients has been found to experience an initial bone flare phenomenon under both standard therapies (androgen deprivation therapy, chemotherapy, radiotherapy, abiraterone, enzalutamide) and novel agents (immunotherapy, bone-targeting radioisotopes). The underlying biological mechanisms of the flare phenomenon are still elusive and need further clarification, particularly in relation to different types of treatment and their treatment response assessment. Flare phenomenon is often underestimated and, in some cases, can negatively affect clinical outcome. In cases with suspected bone flare, the treatment should be continued for a minimum of 12 more weeks before further decisions about efficacy can be taken. Physicians and patients should be aware of this effect to avoid unwarranted anxiety and inadequate early discontinuation of treatment. This review aims at highlighting new evidence on flare phenomenon arising after the introduction of new drugs extending across the biochemical, radiographic and clinical spectrum of the disease.


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