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Nutrients Apr 2019Many cancer patients on intensive chemotherapy lack vitamin C. Vitamin C stimulates the production and activation of immune cells, so perhaps supplementation could be...
Many cancer patients on intensive chemotherapy lack vitamin C. Vitamin C stimulates the production and activation of immune cells, so perhaps supplementation could be used to improve the immunity in those patients. This review assesses the effectiveness and safety of vitamin C administration in cancer. The PubMed and EMBASE databases were searched and all study designs except for phase I studies, and case reports were included in this review. A total of 19 trials were included. In only 4 trials randomization was used to determine if patients received vitamin C or a placebo. The result of this review does not prove that there is a clinically relevant positive effect of vitamin C supplementation in cancer patients in general on the overall survival, clinical status, quality of life (QOL) and performance status (PS), since the quality of the studies published is low. Interventions and patient groups are very diverse, hence an effect in some patient groups is possible. There seems to be a better effect with intravenous than oral administration. Nevertheless, treatment with vitamin C is safe with minimal side effects. Thereby, we think it is safe to examine the effects of vitamin C on specific groups of patients in a randomized controlled setting.
Topics: Ascorbic Acid; Dietary Supplements; Drug Administration Routes; Humans; Neoplasms
PubMed: 31035414
DOI: 10.3390/nu11050977 -
British Journal of Pharmacology Dec 2017The eye is a highly specialized organ that is subject to a huge range of pathology. Both local and systemic disease may affect different anatomical regions of the eye.... (Review)
Review
The eye is a highly specialized organ that is subject to a huge range of pathology. Both local and systemic disease may affect different anatomical regions of the eye. The least invasive routes for ocular drug administration are topical (e.g. eye drops) and systemic (e.g. tablets) formulations. Barriers that subserve as protection against pathogen entry also restrict drug permeation. Topically administered drugs often display limited bioavailability due to many physical and biochemical barriers including the pre-corneal tear film, the structure and biophysiological properties of the cornea, the limited volume that can be accommodated by the cul-de-sac, the lacrimal drainage system and reflex tearing. The tissue layers of the cornea and conjunctiva are further key factors that act to restrict drug delivery. Using carriers that enhance viscosity or bind to the ocular surface increases bioavailability. Matching the pH and polarity of drug molecules to the tissue layers allows greater penetration. Drug delivery to the posterior segment is a greater challenge and, currently, the standard route is via intravitreal injection, notwithstanding the risks of endophthalmitis and retinal detachment with frequent injections. Intraocular implants that allow sustained drug release are at different stages of development. Novel exciting therapeutic approaches include methods for promoting transscleral delivery, sustained release devices, nanotechnology and gene therapy.
Topics: Administration, Ophthalmic; Animals; Biological Availability; Delayed-Action Preparations; Drug Carriers; Drug Delivery Systems; Drug Design; Eye; Eye Diseases; Humans; Nanotechnology; Ophthalmic Solutions
PubMed: 28865239
DOI: 10.1111/bph.14024 -
Advanced Drug Delivery Reviews Dec 2021Strategies of improving vaccine targeting ability toward lymph nodes have been attracting considerable interest in recent years, though there are remaining delivery... (Review)
Review
Strategies of improving vaccine targeting ability toward lymph nodes have been attracting considerable interest in recent years, though there are remaining delivery barriers based on the inherent properties of lymphatic systems and limited administration routes of vaccination. Recently, emerging vaccine delivery systems using various materials as carriers are widely developed to achieve efficient lymph node targeting and improve vaccine-triggered adaptive immune response. In this review, to further optimize the vaccine targeting ability for future research, the design principles of lymph node targeting vaccine delivery based on the anatomy of lymph nodes and vaccine administration routes are first summarized. Then different designs of lymph node targeting vaccine delivery systems, including vaccine delivery systems in clinical applications, are carefully surveyed. Also, the challenges and opportunities of current delivery systems for vaccines are concluded in the end.
Topics: Adaptive Immunity; Antigens; Drug Administration Routes; Drug Delivery Systems; Humans; Lymph Nodes; Nanoparticle Drug Delivery System; Vaccines
PubMed: 34363861
DOI: 10.1016/j.addr.2021.113914 -
Journal of Pharmaceutical Sciences Jan 2021Pulmonary delivery has gained increased interests over the past few decades. For respiratory conditions, targeted drug delivery directly to the site of action can... (Review)
Review
Pulmonary delivery has gained increased interests over the past few decades. For respiratory conditions, targeted drug delivery directly to the site of action can achieve a high local concentration for efficacy with reduced systemic exposure and adverse effects. For systemic conditions, the unique physiology of the lung evolutionarily designed for rapid gaseous exchange presents an entry route for systemic drug delivery. Although the development of inhaled formulations has come a long way over the last few decades, many aspects of it remain to be elucidated. In particular, a reliable and well-understood method for in vitro-in vivo correlations remains to be established. With the rapid and ongoing advancement of technology, there is much potential to better utilise computational methods including different types of modelling and simulation approaches to support inhaled formulation development. This review intends to provide an introduction on some fundamental concepts in pulmonary drug delivery and inhaled formulation development followed by discussions on some challenges and opportunities in the translation of inhaled pharmaceuticals from preclinical studies to clinical development. The review concludes with some recent advancements in modelling and simulation approaches that could play an increasingly important role in modern formulation development of inhaled pharmaceuticals.
Topics: Administration, Inhalation; Computer Simulation; Drug Delivery Systems; Lung; Pharmaceutical Preparations
PubMed: 32916138
DOI: 10.1016/j.xphs.2020.09.006 -
British Journal of Clinical Pharmacology Jan 2015Anaesthesiologists adjust drug dosing, administration system and kind of drug to the characteristics of the patient. They then observe the expected response and adjust... (Review)
Review
Anaesthesiologists adjust drug dosing, administration system and kind of drug to the characteristics of the patient. They then observe the expected response and adjust dosing to the specific requirements according to the difference between observed response, expected response and the context of the surgery and the patient. The approach above can be achieved because on one hand quantification technology has made significant advances allowing the anaesthesiologist to measure almost any effect by using noninvasive, continuous measuring systems. On the other the knowledge on the relations between dosing, concentration, biophase dynamics and effect as well as detection of variability sources has been achieved as being the benchmark specialty for pharmacokinetic-pharmacodynamic (PKPD) modelling. The aim of the review is to revisit the most common PKPD models applied in the field of anaesthesia (i.e. effect compartmental, turnover, drug-receptor binding and drug interaction models) through representative examples. The effect compartmental model has been widely used in this field and there are multiple applications and examples. The use of turnover models has been limited mainly to describe respiratory effects. Similarly, cases in which the dissociation process of the drug-receptor complex is slow compared with other processes relevant to the time course of the anaesthetic effect are not frequent in anaesthesia, where in addition to a rapid onset, a fast offset of the response is required. With respect to the characterization of PD drug interactions different response surface models are discussed. Relevant applications that have changed the way modern anaesthesia is practiced are also provided.
Topics: Anesthetics; Computer Simulation; Dose-Response Relationship, Drug; Drug Administration Routes; Drug Interactions; Humans; Models, Biological
PubMed: 24251846
DOI: 10.1111/bcp.12286 -
Drugs Jul 2017Transdermal administration of analgesic medications offers several benefits over alternative routes of administration, including a decreased systemic drug load with... (Review)
Review
Transdermal administration of analgesic medications offers several benefits over alternative routes of administration, including a decreased systemic drug load with fewer side effects, and avoidance of drug degradation by the gastrointestinal tract. Transdermal administration also offers a convenient mode of drug administration over an extended period of time, particularly desirable in pain medicine. A transdermal administration route may also offer increased safety for drugs with a narrow therapeutic window. The primary barrier to transdermal drug absorption is the skin itself. Transdermal nanotechnology offers a novel method of achieving enhanced dermal penetration with an extended delivery profile for analgesic drugs, due to their small size and relatively large surface area. Several materials have been used to enhance drug duration and transdermal penetration. The application of nanotechnology in transdermal delivery of analgesics has raised new questions regarding safety and ethical issues. The small molecular size of nanoparticles enables drug delivery to previously inaccessible body sites. To ensure safety, the interaction of nanoparticles with the human body requires further investigation on an individual drug basis, since different formulations have unique properties and side effects.
Topics: Administration, Cutaneous; Analgesics; Animals; Drug Delivery Systems; Drug Liberation; Humans; Nanoparticles; Nanotechnology; Skin Absorption
PubMed: 28470586
DOI: 10.1007/s40265-017-0744-y -
European Journal of Pharmaceutics and... Mar 2023Cutaneous melanoma (CM) is a multifactorial disease whose treatment still presents challenges: the rapid progression to advanced CM, which leads to frequent recurrences... (Review)
Review
Cutaneous melanoma (CM) is a multifactorial disease whose treatment still presents challenges: the rapid progression to advanced CM, which leads to frequent recurrences even after surgical excision and, notably, the low response rates and resistance to the available therapies, particularly in the case of unresectable metastatic CM. Thereby, alternative innovative therapeutic approaches for CM continue to be searched. In this review we discuss relevant preclinical research studies, and provide a broad-brush analysis of patents and clinical trials which involve the application of nanotechnology-based delivery systems in CM therapy. Nanodelivery systems have been developed for the delivery of anticancer biomolecules to CM, which can be administered by different routes. Overall, nanosystems could promote technological advances in several therapeutic modalities and can be used in combinatorial therapies. Nevertheless, the results of these preclinical studies have not been translated to clinical applications. Thus, concerted and collaborative research studies involving basic, applied, translational, and clinical scientists need to be performed to allow the development of effective and safe nanomedicines to treat CM.
Topics: Humans; Melanoma; Skin Neoplasms; Nanoparticle Drug Delivery System; Administration, Cutaneous; Melanoma, Cutaneous Malignant
PubMed: 36773725
DOI: 10.1016/j.ejpb.2023.02.002 -
Advanced Drug Delivery Reviews Apr 2021Intercellular tight junctions represent a formidable barrier against paracellular drug absorption at epithelia (e.g., nasal, intestinal) and the endothelium (e.g.,... (Review)
Review
Intercellular tight junctions represent a formidable barrier against paracellular drug absorption at epithelia (e.g., nasal, intestinal) and the endothelium (e.g., blood-brain barrier). In order to enhance paracellular transport of drugs and increase their bioavailability and organ deposition, active excipients modulating tight junctions have been applied. First-generation of permeation enhancers (PEs) acted by unspecific interactions, while recently developed PEs address specific physiological mechanisms. Such target specific tight junction modulators (TJMs) have the advantage of a defined specific mechanism of action. To date, merely a few of these novel active excipients has entered into clinical trials, as their lack in safety and efficiency in vivo often impedes their commercialisation. A stronger focus on the development of such active excipients would result in an economic and therapeutic improvement of current and future drugs.
Topics: Animals; Drug Administration Routes; Drug Delivery Systems; Humans; Tight Junctions
PubMed: 33617902
DOI: 10.1016/j.addr.2021.02.008 -
Progress in Retinal and Eye Research Mar 2017Drug delivery to the posterior eye segment is an important challenge in ophthalmology, because many diseases affect the retina and choroid leading to impaired vision or... (Review)
Review
Drug delivery to the posterior eye segment is an important challenge in ophthalmology, because many diseases affect the retina and choroid leading to impaired vision or blindness. Currently, intravitreal injections are the method of choice to administer drugs to the retina, but this approach is applicable only in selected cases (e.g. anti-VEGF antibodies and soluble receptors). There are two basic approaches that can be adopted to improve retinal drug delivery: prolonged and/or retina targeted delivery of intravitreal drugs and use of other routes of drug administration, such as periocular, suprachoroidal, sub-retinal, systemic, or topical. Properties of the administration route, drug and delivery system determine the efficacy and safety of these approaches. Pharmacokinetic and pharmacodynamic factors determine the required dosing rates and doses that are needed for drug action. In addition, tolerability factors limit the use of many materials in ocular drug delivery. This review article provides a critical discussion of retinal drug delivery, particularly from the pharmacokinetic point of view. This article does not include an extensive review of drug delivery technologies, because they have already been reviewed several times recently. Instead, we aim to provide a systematic and quantitative view on the pharmacokinetic factors in drug delivery to the posterior eye segment. This review is based on the literature and unpublished data from the authors' laboratory.
Topics: Angiogenesis Inhibitors; Animals; Drug Delivery Systems; Humans; Intravitreal Injections; Retina; Retinal Diseases; Tissue Distribution
PubMed: 28028001
DOI: 10.1016/j.preteyeres.2016.12.001 -
South African Medical Journal =... Dec 2023Oral drug formulations and enteral feeds may inadvertently be administered intravenously. Intravenous medications may be inadvertently administered intra-arterially.... (Review)
Review
Oral drug formulations and enteral feeds may inadvertently be administered intravenously. Intravenous medications may be inadvertently administered intra-arterially. These examples of wrong-route drug administration errors have the potential to cause significant organ dysfunction and even death. This narrative review aims to explore the pathophysiological mechanisms underlying such errors and investigate preventive strategies and potential therapeutic options.
Topics: Humans; South Africa; Medication Errors; Administration, Intravenous
PubMed: 38525634
DOI: 10.7196/SAMJ.2023.v113i12.1043