ResearchPad - leading-article https://www.researchpad.co Default RSS Feed en-us © 2020 Newgen KnowledgeWorks <![CDATA[The effects of the COVID-19 pandemic on oncological surgery]]> https://www.researchpad.co/article/elastic_article_10139 The COVID-19 global pandemic is changing the practice of oncologic surgery. Accustomed to fighting cancer with all available means, surgeons are now being asked to delay treatment or make use of alternate strategies to conserve resources. Telemedicine is being widely employed. We present our thoughts on this topic and where we might be in the next several months.

]]>
<![CDATA[In Vivo Delivery of Nucleic Acid-Encoded Monoclonal Antibodies]]> https://www.researchpad.co/article/elastic_article_6107 Antibody immunotherapy is revolutionizing modern medicine. The field has advanced dramatically over the past 40 years, driven in part by major advances in isolation and manufacturing technologies that have brought these important biologics to the forefront of modern medicine. However, the global uptake of monoclonal antibody (mAb) biologics is impeded by biophysical and biochemical liabilities, production limitations, the need for cold-chain storage and transport, as well as high costs of manufacturing and distribution. Some of these hurdles may be overcome through transient in vivo gene delivery platforms, such as non-viral synthetic plasmid DNA and messenger RNA vectors that are engineered to encode optimized mAb genes. These approaches turn the body into a biological factory for antibody production, eliminating many of the steps involved in bioprocesses and providing several other significant advantages, and differ from traditional gene therapy (permanent delivery) approaches. In this review, we focus on nucleic acid delivery of antibody employing synthetic plasmid DNA vector platforms, and RNA delivery, these being important approaches that are advancing simple, rapid, in vivo expression and having an impact in animal models of infectious diseases and cancer, among others.

]]>
<![CDATA[Ongoing Developments and Clinical Progress in Drug-Loaded Red Blood Cell Technologies]]> https://www.researchpad.co/article/elastic_article_6100 Engineered red blood cells (RBCs) appear to be a promising method for therapeutic drug and protein delivery. With a number of agents in clinical trials (e.g., dexamethasone 21-phosphate in ataxia telangiectasia, asparaginase in pancreatic cancer/acute lymphoblastic leukemia, thymidine phosphorylase in mitochondrial neurogastrointestinal encephalomyopathy, RTX-134 in phenylketonuria, etc.), this leading article summarizes the ongoing efforts in developing these agents, focuses on the clinical progress, and provides a brief background into engineered RBCs and the different ways in which they can be exploited for therapeutic/diagnostic purposes. References to available data on safety, efficacy, and tolerability are reported. Due to the continuous progress in this field, the information is updated as of January 2020 from databases, websites, and press releases of the involved companies and information that is in the public domain.

]]>
<![CDATA[Preventing spread of SARS-CoV-2 and preparing for the COVID-19 outbreak in the surgical department: perspectives from two Scandinavian countries]]> https://www.researchpad.co/article/N947e8fbc-65bd-4735-a66f-7d928b06c540 A COVID-19 pandemic was declared on March 11 by the World Health Organization (WHO). The first cases of COVID-19 were confirmed on January 31 in Sweden and on February 26 in Norway. Despite being similar countries with universal healthcare systems, the governmental approaches to mitigation of the epidemic have varied considerably. Norway initiated a societal lockdown effective from March 12, the same day as the first confirmed death. Sweden has initiated a more laxed and gradual strategy based on the appeal for a strong personal sense of responsibility to mitigate the viral spread. In both countries, the first weeks of preparation has seen a strong reduction in elective surgery, with several implemented principles to mitigate SARS-CoV-2 spread and prepare for surgical care for COVID-19 diseases as needed. This invited leading article gives a brief overview of some of the early experiences of the outbreak in two Scandinavian countries.

]]>
<![CDATA[Role of Viral Infection in the Aetiology of Multiple Sclerosis]]> https://www.researchpad.co/article/N77e27420-5256-429a-9ded-ae950703f4fe

Multiple sclerosis (MS) is a chronic disease of the CNS that typically begins in late adolescence or early adulthood. It is highly variable in its expression and severity. The cause of MS is unknown, but both genetic and environmental factors have been implicated in its pathogenesis. It is known that viruses can induce chronic neurological disease, but the pathogenetic process in unclear. A viral cause for MS has been postulated, but to date no single virus has been confirmed to be associated with the disease. Although most viral candidates are no longer considered as possible aetiological agents in MS, a few are still being investigated.

]]>
<![CDATA[Therapeutic and Prophylactic Potential of Small Interfering RNAs against Severe Acute Respiratory Syndrome]]> https://www.researchpad.co/article/N74137cd4-40f0-4c4a-b683-c3c6765129a0

Severe acute respiratory syndrome (SARS), caused by the novel coronavirus SARS-CoV, produced a scare when it appeared in 2003 in China and later quickly spread to other countries around the world. Although it has since disappeared, its threat to human health remains. Therefore, studies on the prevention and treatment of SARS are important for dealing with epidemics of this and other infectious diseases. The most promising newly developed technology for intervention in SARS may be RNA interference, an endogenous cellular process for the inhibition of gene expression mediated by sequence-specific double-stranded RNAs. Numerous studies have reported the therapeutic potential of RNA interference for the treatment of various human diseases ranging from cancers to infectious diseases such as HIV and hepatitis. To date, most studies on inhibition of SARS-CoV replication using small interfering RNAs (siRNAs) have been conducted in cell lines in vitro. One study using siRNAs to inhibit SARS-CoV infection in Rhesus macaques demonstrated that siRNAs were effective both prophylactically and therapeutically with no adverse effects in the animals. Challenges remaining for the application of siRNA in vivo for SARS prevention and treatment include the specificity of the siRNAs and the efficiency of delivery. However, with improvements in siRNA design and delivery methods, RNA interference has the potential to become another major weapon for combating dangerous infections due to viruses such as SARS-CoV.

]]>
<![CDATA[Severe Acute Respiratory Syndrome and Sport]]> https://www.researchpad.co/article/N8e9b12a1-d0b5-4b20-88f0-2d0a200125d7

Severe Acute Respiratory Syndrome (SARS) not only paralysed economic activities in SARS-affected cities, it also affected sporting activities. SARS was identified in Hong Kong in late February 2003 and the WHO issued a global alert on 12 March, 2003. The incubation period of SARS is usually 4–6 days and patients commonly present with high fever (temperature >38°C), dry cough, chills and rigor, dyspnoea and diarrhoea. Although a specific antiviral agent and vaccines for SARS are not available at the time of writing, a standard treatment protocol for SARS has been developed. The average mortality rate is about 16% in Hong Kong.

The coronavirus is a common pathogen for upper respiratory tract infection and is the most probable pathogen for SARS. Transmission methods may, therefore, be similar for both these infections. Transmission is possible when aerosolised viral particles come into contact with the susceptible host’s mucous membrane, most commonly the nose, but also the mouth and eyes.

With appropriate preventive measures to avoid contact with virus, the probability of infection is minimal. Isolation of those who have had close contact with confirmed or suspected SARS patients and/or who have persistent fever will be the most effective and practical method of avoiding contact. Maintaining personal hygiene and frequent hand washing can also reduce the risk of infection. Using diluted bleach (1 part bleach in 99 parts water) to cleanse training areas and equipment is also recommended.

With proper event planning to conform with quarantine measures, special travel arrangements, facility sterilisation and use of venues with good ventilation and filtering systems, sport competition can still proceed.

]]>
<![CDATA[Severe Acute Respiratory Syndrome]]> https://www.researchpad.co/article/N1c556403-f505-486d-8dd1-fe06e02db0a3

Severe acute respiratory syndrome (SARS) is a newly emerged infection that is caused by a previously unrecognized virus–a novel coronavirus designated as SARS-associated coronavirus (SARS-CoV). From November 2002 to July 2003 the cumulative number of worldwide cases was >8000, with a mortality rate of close to 10%. The mortality has been higher in older patients and those with co-morbidities. SARS has been defined using clinical and epidemiological criteria and cases are considered laboratory-confirmed if SARS coronavirus is isolated, if antibody to SARS coronavirus is detected, or a polymerase chain reaction test by appropriate criteria is positive. At the time of writing (24 May 2004), no specific therapy has been recommended. A variety of treatments have been attempted, but there are no controlled data. Most patients have been treated throughout the illness with broad-spectrum antimicrobials, supplemental oxygen, intravenous fluids, and other supportive measures. Transmission of SARS is facilitated by close contact with patients with symptomatic infection. The majority of cases have been reported among healthcare providers and family members of SARS patients. Since SARS-CoV is contagious, measures for prevention center on avoidance of exposure, and infection control strategies for suspected cases and contacts. This includes standard precautions (hand hygiene), contact precautions (gowns, goggles, gloves) and airborne precautions (negative pressure rooms and high efficiency masks). In light of reports of new cases identified during the winter of 2003–4 in China, it seems possible that SARS will be an important cause of pneumonia in the future, and the screening of outpatients at risk for SARS may become part of the pneumonia evaluation.

]]>
<![CDATA[Exercise and Upper Respiratory Tract Infections]]> https://www.researchpad.co/article/N023a88d2-a9e0-4ad0-a451-f0e10803b654 ]]> <![CDATA[The Use of Antiallergic and Antiasthmatic Drugs in Viral Infections of the Upper Respiratory Tract]]> https://www.researchpad.co/article/Nd3c47f51-4828-4c41-89b7-4c1a8d7a1f4f

Summary

Despite their frequency, upper respiratory tract infections (URTIs) constitute an area with few, if any, effective treatment remedies. Asthma and airway allergies share similar pathogenetic mechanisms to URTIs and it is not surprising, therefore, that agents used to treat allergic disorders have also been studied in URTIs. Their possible effects, limitations and hypothetical modes of action in URTIs are reviewed. In controlled clinical trials of satisfactory scientific standard, symptom reductions in both experimental rhinovirus infections and natural colds have occurred with topical anticholinergics, oral antihistamines and topical chromones. Future treatment alternatives for URTIs may include the intranasal anticholinergic ipratropium bromide, new nonsedating antihistamines and sodium cromoglycate (cromolyn sodium). The latter has a record of safety and an absence of adverse effects that would make it an attractive alternative for this common but not particularly serious condition in otherwise healthy individuals.

]]>
<![CDATA[RNAi Therapy for HIV Infection]]> https://www.researchpad.co/article/Nb79881fe-d9aa-4f60-8428-3b32237640a1

Inside eukaryotic cells, small RNA duplexes, called small interfering RNAs (siRNAs), activate a conserved RNA interference (RNAi) pathway which leads to specific degradation of complementary target mRNAs through base-pairing recognition. As with other viruses, studies have shown that replication of the HIV-1 in cultured cells can be targeted and inhibited by synthetic siRNAs. The relative ease of siRNA design and the versatility of RNAi to target a broad spectrum of mRNAs have led to the promise that drug discovery in the RNAi pathway could be effective against pathogens.

This review discusses the current experimental principles that guide the application of RNAi against HIV and describes challenges and limitations that need to be surmounted in order for siRNAs to become practical antiviral drugs. The practical use of RNAi therapy for HIV infection will depend on overcoming several challenges, including the ability to establish long-term expression of siRNA without off-target effects and the capacity to counteract mutant escape viruses.

]]>
<![CDATA[The impact of the COVID-19 pandemic on the provision of surgical care]]> https://www.researchpad.co/article/Nb2c4000b-aca5-4e5c-ab18-696b254122c4 ]]> <![CDATA[Drugs against rhinoviruses]]> https://www.researchpad.co/article/Nfcc12dda-4b19-4c39-b0d1-90f2581c05cf ]]> <![CDATA[Selectin Antagonists]]> https://www.researchpad.co/article/Nd3eac882-362f-4ab2-9962-31ebbcbc7b53

Asthma and COPD are chronic inflammatory conditions that affect hundreds of millions of patients worldwide. New therapeutics are desperately needed, especially those that target the underlying causes and prevent disease progression. Although asthma and COPD have distinct etiologies, both are associated with reduced airflow caused by excess infiltration of inflammatory cells into healthy lung tissues. As selectin-mediated adhesion of leukocytes to the vascular endothelium is a key early event in the initiation of the inflammatory response, selectin inhibition is thought to be a good target for therapeutic intervention.

Three known selectins are expressed in distinct subsets of cells: P-selectin is presented on the surface of activated platelets and endothelial cells, L-selectin is constitutively expressed on leukocytes, and E-selectin synthesis is upregulated in activated endothelial cells. They mediate cell-cell adhesion in the shear flow of the bloodstream via specialized interactions with clusters of oligosaccharides presented on cell surface glycopeptide ligands. The role of selectin-ligand interactions in the inflammatory response has been demonstrated in various animal models, prompting considerable attention from the pharmaceutical industry.

Drug discovery efforts have yielded many different classes of selectin inhibitors, including soluble protein ligands, antibodies, oligosaccharides and small molecules. Although many selectin inhibitors have shown activity in preclinical models, clinical progress of selectin-directed therapies has been slow. Early approaches employed carbohydrate-based inhibitors to mimic the natural ligand sialyl Lewis X; however, these compounds proved challenging to develop. Cytel’s CY 1503, a complex oligosaccharide, progressed to phase II/III trials for reperfusion injury, but further development was halted when it failed to demonstrate clinical efficacy. Two protein-based selectin inhibitors have reached phase II development. These included Wyeth’s recombinant soluble P-selectin ligand, TSI (PSGL-1), which was discontinued after disappointing results in myocardial infarction trials and Protein Design Labs’ humanized anti-L-selectin monoclonal antibody, which is currently in development for trauma. Bimosiamose, discovered by Encysive Pharmaceutical and presently being developed by Revotar Biopharmaceuticals, is an 863 g/mol molecular weight dimer with minimal carbohydrate content and is, to date, the leading selectin inhibitor in clinical development. This compound has shown promise in a phase Ha ‘proof of concept’ trial in patients with asthma, reducing airway recruitment of eosinophils after intravenous administration. Further clinical development of an inhaled formulation is underway.

Despite a significant need for new therapeutics, selectin inhibitors have not yet been explored for the treatment of COPD. Bimosiamose represents an important proof of principle, and hopefully continued success will spark renewed interest in selectin-directed therapeutics for respiratory diseases.

]]>
<![CDATA[Lipid Mediators in Inflammatory Disorders]]> https://www.researchpad.co/article/N54ae2eab-23eb-4b0a-89b9-794b99d02faa

Summary

During the past few decades, intensive collaborative research in the fields of chronic and acute inflammatory disorders has resulted in a better understanding of the pathophysiology and diagnosis of these diseases. Modern therapeutic approaches are still not satisfactory and shock, sepsis and multiple organ failure remain the great challenge in intensive care medicine. However, the treatment of inflammatory diseases like rheumatoid arthritis, ulcerative colitis or psoriasis also represents an unresolved problem.

Many factors contribute to the complex course of inflammatory reactions. Microbiological, immunological and toxic agents can initiate the inflammatory response by activating a variety of humoral and cellular mediators. In the early phase of inflammation, excessive amounts of interleukins and lipid-mediators are released and play a crucial role in the pathogenesis of organ dysfunction. Arachidonic acid (AA), the mother substance of the pro-inflammatory eicosanoids, is released from membrane phospholipids in the course of inflammatory activation and is metabolised to prostaglandins and leukotrienes.

Various strategies have been evaluated to control the excessive production of lipid mediators on different levels of biochemical pathways, such as inhibition of phospholipase A2, the trigger enzyme for release of AA, blockade of cyclooxygenase and lipoxygenase pathways and the development of receptor antagonists against platelet activating factor and leukotrienes. Some of these agents exert protective effects in different inflammatory disorders such as septic organ failure, rheumatoid arthritis or asthma, whereas others fail to do so. Encouraging results have been obtained by dietary supplementation with long chain ω-3 fatty acids like eicosapentaenoic acid (EPA). In states of inflammation, EPA is released to compete with AA for enzymatic metabolism inducing the production of less inflammatory and chemotactic derivatives.

]]>
<![CDATA[The Role of Interleukin-8 and its Receptors in Inflammatory Lung Disease]]> https://www.researchpad.co/article/N2e11d43a-d9c8-4308-b798-faaa5bca293c

Neutrophils have been implicated in the pathogenesis of many inflammatory lung diseases, including the acute respiratory distress syndrome, chronic obstructive pulmonary disease and asthma. The CXC chemokine interleukin (IL)-8, is a potent neutrophil recruiting and activating factor and the detection of IL-8 in clinical samples from patients with these diseases has led clinicians to believe that antagonism of IL-8 may be a practicable therapeutic strategy for disease management.

Work over the last decade has concentrated on both the molecular mechanisms by which IL-8 is produced in the inflammatory setting and also on the manner in which IL-8 activates the neutrophil. Expression of the IL-8 gene appears to be controlled by several components of the inflammatory milieu. Whilst lipopolysaccharide, IL-1β and tumor necrosis factor-α are capable of augmenting IL-8 production, IL-10 is a potent inhibitor of IL-8 synthesis and appears to play an auto-regulatory role. Regulation of the IL-8 gene is under the control of nuclear factor κB which appears to be a primary target for corticosteroid-mediated repression of IL-8 production.

IL-8 exerts is effects on neutrophils by binding with high affinity to two receptors on its cell surface, the chemokine receptors CXCR1 and CXCR2. These closely related receptors belong to the superfamily of G-protein coupled receptors, proteins that historically have proved amenable to antagonism by small molecules. The recent descriptions in the literature of highly potent small molecule antagonists of CXCR2 and their success in blocking in vivo trafficking of neutrophils suggest that antagonsim of IL-8 at the receptor level is a viable therapeutic strategy. Clinical trials of such compounds will ultimately provide crucial information currently lacking and will define whether or not IL-8 blockade provides future therapy in pulmonary disease.

]]>
<![CDATA[Resilience in surgery]]> https://www.researchpad.co/article/N511a7d82-2912-4fe0-89f2-e31aad8999e5 ]]> <![CDATA[Future Costs in Cost-Effectiveness Analyses: Past, Present, Future]]> https://www.researchpad.co/article/5c96117ed5eed0c4847d4c29

There has been considerable debate on the extent to which future costs should be included in cost-effectiveness analyses of health technologies. In this article, we summarize the theoretical debates and empirical research in this area and highlight the conclusions that can be drawn for current practice. For future related and future unrelated medical costs, the literature suggests that inclusion is required to obtain optimal outcomes from available resources. This conclusion does not depend on the perspective adopted by the decision maker. Future non-medical costs are only relevant when adopting a societal perspective; these should be included if the benefits of non-medical consumption and production are also included in the evaluation. Whether this is the case currently remains unclear, given that benefits are typically quantified in quality-adjusted life-years and only limited research has been performed on the extent to which these (implicitly) capture benefits beyond health. Empirical research has shown that the impact of including future costs can be large, and that estimation of such costs is feasible. In practice, however, future unrelated medical costs and future unrelated non-medical consumption costs are typically excluded from economic evaluations. This is explicitly prescribed in some pharmacoeconomic guidelines. Further research is warranted on the development and improvement of methods for the estimation of future costs. Standardization of methods is needed to enhance the practical applicability of inclusion for the analyst and the comparability of the outcomes of different studies. For future non-medical costs, further research is also needed on the extent to which benefits related to this spending are captured in the measurement and valuation of health benefits, and how to broaden the scope of the evaluation if they are not sufficiently captured.

]]>
<![CDATA[Drugs in Development for Malaria]]> https://www.researchpad.co/article/5b5b197c463d7e16c707e1db

The last two decades have seen a surge in antimalarial drug development with product development partnerships taking a leading role. Resistance of Plasmodium falciparum to the artemisinin derivatives, piperaquine and mefloquine in Southeast Asia means new antimalarials are needed with some urgency. There are at least 13 agents in clinical development. Most of these are blood schizonticides for the treatment of uncomplicated falciparum malaria, under evaluation either singly or as part of two-drug combinations. Leading candidates progressing through the pipeline are artefenomel–ferroquine and lumefantrine-KAF156, both in Phase 2b. Treatment of severe malaria continues to rely on two parenteral drugs with ancient forebears: artesunate and quinine, with sevuparin being evaluated as an adjuvant therapy. Tafenoquine is under review by stringent regulatory authorities for approval as a single-dose treatment for Plasmodium vivax relapse prevention. This represents an advance over standard 14-day primaquine regimens; however, the risk of acute haemolytic anaemia in patients with glucose-6-phosphate dehydrogenase deficiency remains. For disease prevention, several of the newer agents show potential but are unlikely to be recommended for use in the main target groups of pregnant women and young children for some years. Latest predictions are that the malaria burden will continue to be high in the coming decades. This fact, coupled with the repeated loss of antimalarials to resistance, indicates that new antimalarials will be needed for years to come. Failure of the artemisinin-based combinations in Southeast Asia has stimulated a reappraisal of current approaches to combination therapy for malaria with incorporation of three or more drugs in a single treatment under consideration.

]]>
<![CDATA[Global Access Programs: A Collaborative Approach for Effective Implementation and Management]]> https://www.researchpad.co/article/5ae5b7b7463d7e36691e2933

Global access programs (GAPs) provide access to medicinal products for patients with serious medical conditions and no commercially available treatment options. Providing early access to medicines can be challenging for a pharmaceutical company. The demand for a GAP often occurs at a time when other activities are the prime focus, such as delivery of pivotal clinical trials or gaining of marketing authorization. Furthermore, the skills, experience, and infrastructure necessary to implement and manage a successful GAP vary significantly from those required for regular clinical trial execution, and the regulatory environment presents its own challenges, with regulations often poorly defined and with considerable inter-country variation. This article considers the triggers for early access requests and examines the need for companies to develop a global strategy for GAPs in order to respond appropriately to requests for early access. It also provides a comprehensive overview of the processes for GAP set-up, implementation, management, and closure, along with the considerations affecting the type and scope of GAP, such as demand, regulatory feasibility, license status of the product, drug pricing structure, company strategy, costs, and product supply. Also discussed is the need for appropriate personnel to implement and manage the GAP, and when to consider collaboration with an external GAP provider. In summary, GAPs require careful and efficient planning and management, from set-up to closure. Well-run GAPs provide an ethical and regulatory-compliant pathway for access of new treatments to patients with serious conditions and an unmet medical need.

]]>