Thousands Of Drugs Research Articles

Pharmaceutical manufacturer liability for unreasonable marketing

The Supreme Court of Pennsylvania recently reversed dismissal of a lawsuit brought against a pharmaceutical manufacturer. That court accepted the argument that a manufacturer may be liable for marketing a drug that is unreasonably dangerous for any patient. This ruling has the potential to expand the liability of pharmaceutical manufacturers beyond the traditional lawsuits based on manufacturing defects and the failure to warn.

Machine Learning Prediction of Cancer Cell Sensitivity to Drugs Based on Genomic and Chemical Properties

Predicting the response of a specific cancer to a therapy is a major goal in modern oncology that should ultimately lead to a personalised treatment. High-throughput screenings of potentially active compounds against a panel of genomically heterogeneous cancer cell lines have unveiled multiple relationships between genomic alterations and drug responses. Various computational approaches have been proposed to predict sensitivity based on genomic features, while others have used the chemical properties of the drugs to ascertain their effect. In an effort to integrate these complementary approaches, we developed machine learning models to predict the response of cancer cell lines to drug treatment, quantified through IC50 values, based on both the genomic features of the cell lines and the chemical properties of the considered drugs. Models predicted IC50 values in a 8-fold cross-validation and an independent blind test with coefficient of determination R2 of 0.72 and 0.64 respectively. Furthermore, models were able to predict with comparable accuracy (R2 of 0.61) IC50s of cell lines from a tissue not used in the training stage. Our in silico models can be used to optimise the experimental design of drug-cell screenings by estimating a large proportion of missing IC50 values rather than experimentally measuring them. The implications of our results go beyond virtual drug screening design: potentially thousands of drugs could be probed in silico to systematically test their potential efficacy as anti-tumour agents based on their structure, thus providing a computational framework to identify new drug repositioning opportunities as well as ultimately be useful for personalized medicine by linking the genomic traits of patients to drug sensitivity.

New Life for an Old Drug: the Anthelmintic Drug Niclosamide Inhibits Pseudomonas aeruginosa Quorum Sensing

The need for novel antibacterial strategies and the awareness of the importance of quorum sensing (QS) in bacterial infections have stimulated research aimed at identifying QS inhibitors (QSIs). However, clinical application of QSIs identified so far is still distant, likely due to their unsuitability for use in humans. A promising way to overcome this problem is searching for anti-QS side activity among the thousands of drugs approved for clinical use in the treatment of different diseases. Here, we applied this strategy to the search for QSIs, by screening a library of FDA-approved compounds for their ability to inhibit the QS response in the Gram-negative pathogen Pseudomonas aeruginosa. We found that the anthelmintic drug niclosamide strongly inhibits the P. aeruginosa QS response and production of acyl-homoserine lactone QS signal molecules. Microarray analysis showed that niclosamide affects the transcription of about 250 genes, with a high degree of target specificity toward the QS-dependent regulon. Phenotypic assays demonstrated that niclosamide suppresses surface motility and production of the secreted virulence factors elastase, pyocyanin, and rhamnolipids, and it reduces biofilm formation. In accordance with the strong antivirulence activity disclosed in vitro, niclosamide prevented P. aeruginosa pathogenicity in an insect model of acute infection. Besides the finding that an FDA-approved drug has a promising antivirulence activity against one of the most antibiotic-resistant bacterial pathogens, this work provides a proof of concept that a lateral anti-QS activity can be detected among drugs already used in humans, validating a new approach to identify QSIs that could easily move into clinical applications.

Behavioral screening for neuroactive drugs in zebrafish

The larval zebrafish has emerged asa vertebrate model system amenable to small molecule screens for probing diverse biological pathways. Two large-scale small molecule screens examined the effects of thousands of drugs on larval zebrafish sleep/wake and photomotor response behaviors. Both screens identified hundreds of molecules that altered zebrafish behavior in distinct ways. The behavioral profiles induced by these small molecules enabled the clustering of compounds according to shared phenotypes. This approach identified regulators of sleep/wake behavior and revealed the biological targets for poorly characterized compounds. Behavioral screening for neuroactive small molecules in zebrafish is an attractive complement to in vitro screening efforts, because the complex interactions in the vertebrate brain can only be revealed in vivo.

Current use of high-resolution mass spectrometry in drug screening relevant to clinical and forensic toxicology and doping control

Clinical and forensic toxicology and doping control deal with hundreds or thousands of drugs that may cause poisoning or are abused, are illicit, or are prohibited in sports. Rapid and reliable screening for all these compounds of different chemical and pharmaceutical nature, preferably in a single analytical method, is a substantial effort for analytical toxicologists. Combined chromatography-mass spectrometry techniques with standardised reference libraries have been most commonly used for the purpose. In the last ten years, the focus has shifted from gas chromatography-mass spectrometry to liquid chromatography-mass spectrometry, because of progress in instrument technology and partly because of the polarity and low volatility of many new relevant substances. High-resolution mass spectrometry (HRMS), which enables accurate mass measurement at high resolving power, has recently evolved to the stage that is rapidly causing a shift from unit-resolution, quadrupole-dominated instrumentation. The main HRMS techniques today are time-of-flight mass spectrometry and Orbitrap Fourier-transform mass spectrometry. Both techniques enable a range of different drug-screening strategies that essentially rely on measuring a compound's or a fragment's mass with sufficiently high accuracy that its elemental composition can be determined directly. Accurate mass and isotopic pattern acts as a filter for confirming the identity of a compound or even identification of an unknown. High mass resolution is essential for improving confidence in accurate mass results in the analysis of complex biological samples. This review discusses recent applications of HRMS in analytical toxicology.

Media and Book Reviews: Medications: How can we know them all?

When are you planning to study all the important details of the more than 20 new drugs that get approved each year by the Food and Drug Administration (FDA)? Similarly, what about the hundreds of labels, interactions, and side effect profiles that are constantly being updated? Likely, the answer is never. Yet a major component of clinical practice relates to drugs and the ever-changing details about them. Many have turned to mobile applications for smartphones, tablets, and PDAs for updates on the go. I selected 4 common apps, all of which are free and available on multiple mobile platforms (all are available for Apple, Blackberry, and Android platforms; Medscape is not available for Palm or Windows Mobile). I tested these apps on the Apple iPad and iPhone. All 4 allow automatic updating without special steps by the user. All 4 provide detailed monographs on thousands of drugs, including indications, dosing, adverse effects, pharmacology, and more. If you want the bottom line without getting into the details, I recommend getting all 4 apps. Each …

Aliphatic and Aromatic Oxidations, Epoxidation and S-Oxidation of Prodrugs that Yield Active Drug Metabolites

About one hundred and fifty of the several thousands of drugs on the market are known to have active metabolites. Medicinal chemistry of the parent drugs as well as that of the metabolites are very important both in medical practice and drug research. The efficacy of a drug will depend on a number of properties including, pharmacokinetic behavior, absorption, tissue distribution, pharmacological potency, toxicity and tissue-specificity. The production and release of active metabolites are important because active drug metabolites may influence the clinical outcome of a drug by increasing the gross level of pharmacologically active compounds (drug + active metabolite) and/or essentially increasing the duration of drug effect, when t(1/2) of active metabolite is much longer than that of the parent drug. Furthermore, certain drug metabolizing enzymes can either be inhibited or induced by other drugs and a variety of food and environmental factors. A careful control of the clinical effects of any drug with active metabolites is important especially in the treatment of the elderly population where the administration of several drugs is not unusual.This review provides a detailed description of the medicinal chemistry of drugs yielding active metabolites after undergoing transformation via aliphatic and aromatic oxidations, epoxidation and S-oxidation. Their respective pharmacologically active metabolites, metabolizing enzymes and changes in lipophilicity are also summarized. The most recent analytical methods used for the reliable quantification of both the parent drugs and their metabolites are also included.

Using the fish plasma model for comparative hazard identification for pharmaceuticals in the environment by extrapolation from human therapeutic data

Thousands of drugs are currently in use, but only for a few of them experimental chronic fish data exist. Therefore, Huggett et al. (Human Ecol Risk Assess 2003; 9:1789–1799) proposed the fish plasma model (FPM) to extrapolate the potential of unintended long-term effects in fish. The FPM compares human therapeutic plasma concentrations (HPCT) with estimated fish steady-state concentrations (FPCss), under the assumption that biological drug targets may be conserved across the species. In this study, the influence of using different input parameters on the model result was characterised for 42 drugs. The existence of structurally and functionally conserved protein targets in zebrafish could not be refuted. Thus, the FPM model application was not in contradiction to its basic assumption. Further, dissociation of drugs was shown to be important in determining the output and model robustness. As the proposed model for FPCss estimation was considered to predict accurate values for neutral and lipophilic chemicals only, a modified bioconcentration model was used with DOW as predictor. Using reasonable worst case assumptions, a hazard was indicated for one third of the selected drugs. Our results support the notion that this approach might help to prioritise among in use drugs to identify compounds where follow up evidence should be considered.

Conventional and Novel Approaches in Generating and Characterization of Reactive Intermediates from Drugs/Drug Candidates

Despite several thousands of drugs are in use currently, research on new drug molecules is continuing. Because, there are diseases still without medication, successor/better drugs make the predecessor ones obsolete, and advancement in both life sciences and analytical technologies provide identification of previously unknown mechanisms of diseases, and discovery of novel drug targets. The two main criteria which a drug candidate should meet are high affinity for the target, and no or acceptable/tolerable toxicity in humans. Among these two, toxicity is the limiting one; developing a drug candidate with unacceptable toxicity has to be discontinued, even if it has an extremely high pharmacological activity. Drug would be withdrawn, if serious toxicity arises after marketing. Since drug development is a long (approximately 10 years), expensive, and infertile (one lead in 10.000 molecules) process, it is extremely important to detect the potential toxicity of drug candidate as early as possible. Today, it is believed that a great majority of toxic effects are caused by reactive intermediates generated by biotransformation of the parent drug. However, there are experimental difficulties in identifying such metabolite(s) in vivo. Their formation is affected by multi-factorial events; they can further be metabolized to structurally different products, and/or they may bind to a huge variety of biological sites or macromolecules. Hence, some reactive intermediates and their corresponding stable derivatives are generated in trace amounts, which make their determination more difficult. The ability of cytochrome P450s (CYP450) and other biotransformation enzymes to function in vitro offers a great flexibility to researchers, biotransformation of any compound can be simulated in a test tube, and metabolites/reactive intermediates are generated in an environment which has relatively much less background and less interfering multi-factorial events compared to in vivo. To simulate biotransformation, microsomal fraction is used most frequently from human and non-human sources. Purified or recombinant enzymes are used in determining the individual isoenzymes responsible for certain metabolites. Because of the chemical reactivity of intermediates, relevant, usually nucleophilic trapping agent(s) such as glutathione (GSH), N-acetylcysteine (NAC) and cyanide (CN-) are used to stabilize the metabolite. Trapped metabolites are subjected to spectrometric and/or nuclear magnetic resonance spectroscopic analyses for structural identification. Vertiginous advances especially in mass spectrometric technologies offer researchers new challenges in this area. This review is aimed at briefly summarizing the state of the art and compiling the highlighted studies in characterization of the reactive metabolites from drug molecules.

Screening Thousands of Drugs in Leukemia Patient Samples to Identify Novel Uses for Approved Drugs.

Abstract 4414 IntroductionDiscovery of novel non cytotoxic drugs for cancer focuses on targets selectively expressed in malignant cells, only testing at the end if they are toxic to patients. We have developed a novel approach to discover these drugs starting at the end; we screen 2.000 approved drugs with proven safety, directly on freshly extracted (ex vivo) blood samples of patients with Chronic Lymphocytic Leukemia (CLL). These screens are enabled by a novel technology platform based on automated flow cytometry we call ExviTech for ex vivo technology. Patients and MethodsAll screening studies were performed directly on either peripheral blood or bone marrow samples from 44 patients diagnosed with various subtypes of B-cell malignancies, after informed consent. Patient samples were diluted and plated with each of the 2.000 drugs individually, retaining the erythrocyte population and serum proteins to enable clinically relevant concentrations. The experimental assay was setup the same or a day after sample extraction. Each sample was diluted to achieve a leukemic cell concentration of approximately 3,000 cells/μl; then 45μl of the suspension is added to each well of 96-well plates that contain the pharmacological agents (final concentration of 30μM). The compound plates were then sequentially incubated for 24 hours at 37°C with 5% CO2 for screening (sterile conditions). After incubation, the erythrocytes were lysed and the leucocytes incubated with Annexin V-FITC, anti-CD45-APC and anti-CD19-PE added to each well. The plates were then transferred to an automated flow cytometry system where the contents of each well were aspirated and analyzed by a CyAn flow cytometer. Candidates from the primary screens were validated in additional samples with dose-responses, combinations with approved drugs, multiple incubation times, etc… ResultsAnalyzing primary screens from 24 CLL patients, three related compounds (Vivia007, Vivia008 and Vivia009) were found to consistently induce apoptosis of nearly all leukemic B-cells from most of the patient samples diagnosed with B-cell chronic lymphocytic leukemia at levels equal to or greater than known CLL active cytotoxic agents. Notably, these candidates are equally effective against samples of p53 mutated patients. These 3 drugs are pharmacologically me-too drugs sharing the same target and mechanism of action, and are non cytotoxic drugs with a known and good safety profile, administered to millions of patients over many years. Validation experiments were done on 20 additional CLL patients and Vivia009 emerged as the most effective agent with an average EC50 of 18.2μM. The mechanism of action is different than the known mechanism of Vivia009 and its class members for their approved indications. Consistent with this observation, only 3 of 15 members of the same pharmacological drug class were efficacious against CLL malignant cells. All 3 Vivia′s candidates were equally efficacious against other B-Cell Malignancies such as B-ALL (pediatric and adult), and Multiple Myeloma. These drugs are not effective in their current oral formulation and require a novel intravenous formulation. Interestingly, kinetics of induction of apoptosis were faster for Vivia009 than for fludarabine, cyclophosphamide and mitoxantrone. Vivia009 requires only 1 hour of incubation with fresh cells to induce maximal apoptosis. This timeline is less than the 3 hours in which Vivia009 was found present at high concentrations in bone marrow of rats using a single intravenous bolus. Thus, Vivia009 seems to fulfill the pharmacokinetic criteria to eliminate all leukemic cells with a single intravenous bolus, which would be a major advantage over current treatments (5-days fludarabine or 3 days FCR). Animal models are ongoing to confirm the non cytotoxic nature of the candidates in the novel IV formulation and the fewer days needed to reach remission, both compared with fludarabine monotherapy. ConclusionsIn summary, our results demonstrate the potential of the ExviTech technology platform as a successful model for the systematic search of new uses for already existing approved drugs directly on patient samples of hematological malignancies. A new drug candidate with excellent safety profile has been identified with similar efficacy ex vivo as the best approved cytotoxic drugs, which is a non-cytotoxic drug with fast kinetics that might enable significantly safer and shorter treatments. Disclosures:Bennett:Vivia Biotech: Employment. Sapia:Vivia Biotech SL: Employment. Primo:Vivia Biotech SL: Employment. Suarez:Vivia Biotech SL: Employment. Lago:Vivia Biotech SL: Employment. Matoses:Vivia Biotech: Employment. Espinosa:Vivia Biotech: Ana Espinosa, Employment. Tudela:Vivia Biotech SL: Employment. Arroyo:Vivia Biotech SL: Employment. Jackson:Vivia Biotech SL: Employment. Okun:Vivia Biotech SL: Research Funding. Lopez:Vivia Biotech SL: Employment. Gornemann:Vivia Biotech SL: Employment. Diez:Vivia Biotech SL: Employment. González:Vivia Biotech SL: Consultancy. Dominguez-Gil:Vivia Biotech SL: Consultancy. Troconiz:Vivia Biotech SL: Consultancy. Rodriguez de Fonseca:Vivia Biotech SL: Consultancy. Saunders:Vivia Biotech: Consultancy. Montejo:Vivia Biotech SL: Consultancy. Caveda:Vivia Biotech SL: Employment. Orfao:Vivia Biotech SL: Research Funding. Ballesteros:Vivia Biotech SL: Equity Ownership.

Closing a Loophole in the FDA Amendments Act

In their Policy Forum “Moving toward transparency of clinical trials” (7 March, p. [1340][1]), D. A. Zarin and T. Tse caution that “FDAAA 801 still leaves areas of 'opacity.'” We would like to point out another loophole: FDAAA 801 will only cover future drugs. The thousands of drugs on the

Who is Responsible for Evaluating the Safety and Effectiveness of Medical Devices? The Role of Independent Technology Assessment

IntroductionThe global medical technology industry brings thousands of devices to market every year. However, significant gaps persist in the scientific literature, in the medical device approval process, and in the realm of postmarketing surveillance. Although thousands of drugs obtain approval only after review in randomized controlled trials, relatively few new medical devices are subject to comparable scrutiny.ObjectiveTo improve health outcomes, we must enhance our scrutiny of medical devices, and, without simply deferring to the Food and Drug Administration, we must ask ourselves: Who is responsible for evaluating the safety and effectiveness of medical devices?ConclusionsTechnology assessments by independent organizations are a part of the solution to this challenge and may motivate further research focused on patient outcomes.

In One Ear and Out the Other: Communication Barriers as a Risk Factor for Critical Incidents

In One Ear and Out the Other: Communication Barriers as a Risk Factor for Critical Incidents

From the liver to the brain across the blood–brain barrier

The burden of brain diseases as established by a recent report of the World Health Organization represents 30% of the total burden of all diseases. This surprisingly high number is clearly related to the fact that the presently available CNS drugs treat only an extremely small percentage of brain diseases, leaving untreated major disorders, such as Alzheimer's disease, brain cancer, and stroke, or minor ones, such as autism, inherited mental retardation, and ataxia. There are also relatively few CNS drugs, although not for a lack of trying. In fact, ceaseless efforts have been made by the pharmaceutical industry to develop CNS drugs, but the number of failures has unfortunately paralleled the thousands of drugs that have been designed and tested. A major stumbling block has remained the fact that very few drugs have the ability to cross the blood–brain barrier (BBB) and reach their targets within the brain parenchyma (1). The BBB is created by the endothelial cells that provide the walls of the blood vessels perfusing the brain. However, in contrast to the peripheral endothelium, the brain endothelial cells lack capillary fenestrations, display low pinocytic activity, and form very tight junctions that are highly resistant to transendothelial ionic fluxes and strictly limit the entrance of endogenous and exogenous compounds into the CNS. How to successfully negotiate the barrier has required a deep understanding of its intimate properties and a great deal of ingenuity. The paper by Spencer and Verma (2) in this issue of PNAS is a good example of the latter with some extra creativity. To fully appreciate …

Recognizing cutaneous drug eruptions

PREVIEWConsidering the thousands of drugs prescribed every day and the large number of over-the-counter drugs available to patients, it is not surprising that cutaneous drug eruptions are a significant problem. In this review, Drs Daoud, Schanbacher, and Dicken focus on recognition of drug reactions, analysis of the history of drug exposure, confirmation of the diagnosis, and identification of clinical entities that require dermatologic consultation.

Using computerized individual medication data to detect drug effects on clinical laboratory tests.

In clinical practice, thousands of drugs are used daily. Clinicians know the therapeutic effects of drugs but other minor drug effects are often ignored either because of inadequate knowledge of these effects or simply because of the limited memory capacity of a human being. This problem can be solved by using a computerized information system, which includes medication data of individual patients as well as information about non-therapeutic drug-effects. One of these non-therapeutic confusing drug effects is the influence of drugs on laboratory tests; a problem that should be taken into account in clinical practice and diagnostics. Other complicating drug effects include drug interactions and patient related adverse drug reactions. In a computerized information system, it is possible to build decision support modules that automatically give alarms or alerts of important drug effects other than therapeutic effects. If these warnings concern laboratory tests they are checked by a laboratory physician and only those with clinical significance are sent to clinicians. Warnings of drug interactions and adverse drug reactions are immediately evaluated by the physician responsible for the treatment. By means of the computerized information system, it is also possible to get better information of current medication practice which in turn gives better chances to agree on common guidelines and enables better quality assurance.

New designs for radiation oncology research in clinical trials.

A research logic model and matrix’ is presented to serve as a framework for combining treatment modalities utilized in current cancer management and for developing innovations in radiation oncology. The stimulus for this effort is the need for a better scientific basis for launching clinical trials, particularly when such new modes as radiosensitizers, radioprotectors, hyperthermia, high linear energy transfer (LET), and radiolabeled tumor antibodies are added to the existing established modes such as surgery, radiation, and chemotherapy. Since common research themes are being explored with radiation and drugs, many opportunities exist to integrate these two major research approaches. Radiobiology research received its major impetus at the beginning of the atomic era, when the biologic effects of high dose and low chronic dose radiation exposure required definition. As a by-product of this effort, radiation has acted as a noninvasive probe into living organisms. Radiation perturbs biologic systems through its selective action on dividing cells, and has led to observations of prime biologic importance. As methods of cell quantification were developed in in vitro and in vivo systems, more research was directed toward understanding the mechanisms of action of radiation at the cellular and tissue levels The four “R’s“ of clinical radiobiologic research as stated by Whitmore’-repair, reoxygenation, repopulation, and reassortment-have been the main currents of tumor biology research during the past decade. Unlike the radiation research program, the drug development program3 of the National Cancer Institutue (NCI) evolved a linear treatment array from pharmacology research programs. The initial step involves the use of a drug prescreening program based on tumor response in one or two sensitive cell lines to evaluate thousands of drugs. Once a drug is shown to have an antitumor effect, a more intensive screening analysis is made using a panel of mouse tumors and xenografts of common human tumors. If the drug is effective and not too toxic in this panel of mouse tumors, large scale production and