Search

Accurate prediction of synergistic effects of drug combinations can reduce the experimental costs for drug development and facilitate the discovery of novel efficacious combination therapies for clinical studies. The drug combinations with high synergy scores are regarded as synergistic ones, while those with moderate or low synergy scores are additive or antagonistic ones. The existing methods usually exploit the synergy data from the aspect of synergistic drug combinations, paying little attention to the additive or antagonistic ones. Also, they usually do not leverage the common patterns of drug combinations across different cell lines. In this paper, we propose a multi-channel graph autoencoder (MGAE)-based method for predicting the synergistic effects of drug combinations (DC), and shortly denote it as MGAE-DC. A MGAE model is built to learn the drug embeddings by considering not only synergistic combinations but also additive and antagonistic ones as three input channels. The later two channels guide the model to explicitly characterize the features of non-synergistic combinations through an encoder-decoder learning process, and thus the drug embeddings become more discriminative between synergistic and non-synergistic combinations. In addition, an attention mechanism is incorporated to fuse each cell-line's drug embeddings across various cell lines, and a common drug embedding is extracted to capture the invariant patterns by developing a set of cell-line shared decoders. The generalization performance of our model is further improved with the invariant patterns. With the cell-line specific and common drug embeddings, our method is extended to predict the synergy scores of drug combinations by a neural network module. Experiments on four benchmark datasets demonstrate that MGAE-DC consistently outperforms the state-of-the-art methods. In-depth literature survey is conducted to find that many drug combinations predicted by MGAE-DC are supported by previous experimental studies. The source code and data are available at https://github.com/yushenshashen/MGAE-DC. Author summary: Drug combination therapy is widely employed for various complex diseases because of its advantages of enhancing the efficiency, overcoming the drug resistance and reducing dose-dependent toxicity relative to monotherapy. To identify novel reliable and efficacious drug combinations for the patients, various methods have been proposed in the past decades. The trial-based methods are based on the clinical trials directly, but may cause patients to receive unnecessary or even harmful treatments. The experimental methods are labour and cost intensive, it is infeasible to test the complete drug combination space due to the combinatorial explosion. Computational methods provide attractive solutions to make the prediction based on the known data in silico, and thus narrow down the searching range of potential combinations. We have developed a novel deep learning method, named MGAE-DC, for predicting the synergistic effects of drug combinations. Our method explicitly characterizes not only synergistic combinations but also non-synergistic ones to obtain discriminative drug embeddings. Our method also learns common features of drug combinations across the cell lines for improved generalization performance. Computational experiments have verified the effectiveness of MGAE-DC. [ABSTRACT FROM AUTHOR]

Background: Malaria remains one of the leading causes of morbidity, and mortality in Uganda. A large proportion of malaria symptomatic patients seek healthcare in private sector. However, availability and affordability are major barriers to access to effective treatment. The private sector copayment mechanism in Uganda aims to increase availability and affordability of antimalarial agents. Our study assessed availability, price, and market share of quality assured artemisinin-based combination therapies (QAACTs) in private drug outlets in selected districts during the implementation of copayment mechanism. Methods: This was a cross-sectional survey of anti-malarial agents in private drug outlets in in selected moderate-to-high (Tororo, and Apac districts) and low (Kabale and Mbarara districts) malaria transmission settings. Following the World Health Organization/Health Action International (WHO/HAI) criteria, an audit of the antimalarial agents was done using a checklist to determine availability, price, and market share of QAACTs. Data were entered in Epi-data and analyzed in STATA ver 14.0 at 95% confidence level. Results: A total of twenty-eight (28) private drug outlets (pharmacies and drug shops) were included in the survey. One in seven (20/144: 95%CI: 9.1, 20.6) of the antimalarial agents in private drug outlets were quality assured artemisinin-based combination therapies (QAACT). Artemether-lumefantrine (AL), 8.9% (11/124) and Artesunate-Amodiaquine (AQ), 7.3% (9/124) were the only QAACTs present in the drug outlets at the time of the survey. The majority, 86.1%% (124/144) of antimalarial agents present in stock in the drug outlets were artemisinin based. The most common, 38.9% (56/144) ACT in the drug outlets was Dihydroartemisinin-Piperaquine (DHP). Most, 69.4% (100/144) of the antimalarial agents were in high malaria transmission settings. The cost of ACT antimalarial agents is high in the country, USD 1.4 (Artemether-Lumefantrine, AL), USD 2.4 (Dihydroartemisinin-Piperaquine, DP), the first line and second-line agents respectively for treatment of uncomplicated malaria in Uganda. There was a statistically significant difference between the dispensing price of 'Green leaf' ACTs (QAACT) and the recommended price (p<0.001). Predictors of availability of QAACT in private drug outlets include pharmacy drug outlet (aPR:0.4; 95%CI: 0.2, 0.9) and dispensing price more than 3000UGX (USD 0.83) (aPR: 0.4, 95%CI: 0.1, 0.51). Conclusion: Quality assured artemisinin-based combination therapies (QAACTs) are not common in private drug outlets in selected districts in Uganda. All the drug outlets had at least one ACT antimalarial agent present on the day of the survey. The dispensing price of QAACTs was significantly higher than the recommended markup price. There is need for awareness creation, surveillance, and monitoring of the implementation of Copayment mechanism in the country. [ABSTRACT FROM AUTHOR]

Drug combination therapies can improve drug efficacy, reduce drug dosage, and overcome drug resistance in cancer treatments. Current research strategies to determine which drug combinations have a synergistic effect rely mainly on clinical or empirical experience and screening predefined pools of drugs. Given the number of possible drug combinations, the speed, and scope to find new drug combinations are very limited using these methods. Due to the exponential growth in the number of drug combinations, it is difficult to test all possible combinations in the lab. There are several large-scale public genomic and phenotypic resources that provide data from single drug-treated cells as well as data from small molecule treated cells. These databases provide a wealth of information regarding cellular responses to drugs and offer an opportunity to overcome the limitations of the current methods. Developing a new advanced data processing and analysis strategy is imperative and a computational prediction algorithm is highly desirable. In this paper, we developed a computational algorithm for the enrichment of synergistic drug combinations using gene regulatory network knowledge and an operational module unit (OMU) system which we generate from single drug genomic and phenotypic data. As a proof of principle, we applied the pipeline to a group of anticancer drugs and demonstrate how the algorithm could help researchers efficiently find possible synergistic drug combinations using single drug data to evaluate all possible drug pairs. [ABSTRACT FROM AUTHOR]

Drug resistance is a primary obstacle in cancer treatment. In many patients who at first respond well to treatment, relapse occurs later on. Various mechanisms have been explored to explain drug resistance in specific cancers and for specific drugs. In this paper, we consider resistance to anti-PD-1, a drug that enhances the activity of anti-cancer T cells. Based on results in experimental melanoma, it is shown, by a mathematical model, that resistances to anti-PD-1 can be significantly reduced by combining it with anti-TNF-α. The model is used to simulate the efficacy of the combined therapy with different range of doses, different initial tumor volume, and different schedules. In particular, it is shown that under a course of treatment with 3-week cycles where each drug is injected in the first day of either week 1 or week 2, injecting anti-TNF-α one week after anti-PD-1 is the most effective schedule in reducing tumor volume. [ABSTRACT FROM AUTHOR]

Published studies have generated compelling results indicating that type I IFN modulates function of HSV-1 latency-associated transcript (LAT). One member of type I IFN is IFNα2A also called Roferon-A). IFNα2A has been used in monotherapy or in combination therapy with other drugs to treat viral infections and different kinds of cancer in humans. The goal of this study was to determine whether the absence of IFNα2A affects primary and latent infections in ocularly infected mice. Therefore, we generated a mouse strain lacking IFNα2A expression (IFNα2A-/-). Ocular HSV-1 replication, IFN and immune cell expressions on days 3 and 5 post infection (PI), as well as eye disease, survival, latency-reactivation, and T cell exhaustion were evaluated in ocularly infected IFNα2A-/- and wild type (WT) control mice. Absence of IFNα2A did not affect other members of the IFNα family but it affected IFNβ and IFNγ expressions as well as some immune cells on day 5 PI compared to WT mice. Viral replication in the eye, eye disease, and survival amongst ocularly infected IFNα2A-/- mice were similar to that of WT infected mice. The absence of IFNα2A significantly reduced the levels of latency and T cell exhaustion but not time of reactivation compared with control mice. Our results suggest that blocking IFNα2A expression may be a useful tool in reducing latency and the subsequent side effects associated with higher levels of latency. Author summary: Many viruses have evolved strategies to circumvent the IFN system, including (i) inhibition of IFN production; (ii) blocking of downstream signaling events that occur after cytokine-receptor binding; and (iii) inhibition of the functions of proteins, which are induced by IFN, including apoptotic proteins. The interferons (IFNs) are of considerable interest in the control of HSV-1 infection due to their rapid generation in response to viral infection and their antiviral activities. Type I interferons, which includes interferon alpha (IFNα), are a family of cytokines important for control of viral infections. There are at least 14 IFNα genes in mouse, amongst which includes the gene encoding IFNα2A that play an important role in human studies. The mechanisms by which HSV-1 interferes with type I IFN responses during primary infection, establishment of latency and reactivation are not fully understood. Thus, to evaluate the importance of IFNα2A on HSV-1 infectivity, we generated IFNα2A knockout mice. The absence of IFNα2A significantly reduced latency and T cell exhaustion, but not virus reactivation. [ABSTRACT FROM AUTHOR]

Oncolytic virus (OV) is a replication competent virus that selectively invades cancer cells; as these cells die under the viral burden, the released virus particles proceed to infect other cancer cells. Oncolytic viruses are designed to also be able to stimulate the anticancer immune response. Thus, one may represent an OV by two parameters: its replication potential and its immunogenicity. In this paper we consider a combination therapy with OV and a checkpoint inhibitor, anti-PD-1. We evaluate the efficacy of the combination therapy in terms of the tumor volume at some later time, for example, 6 months from initial treatment. Since T cells kill not only virus-free cancer cells but also virus-infected cancer cells, the following question arises: Does increasing the amount of the checkpoint inhibitor always improve the efficacy? We address this question, by a mathematical model consisting of a system of partial differential equations. We use the model to construct, by simulations, an efficacy map in terms of the doses of the checkpoint inhibitor and the OV injection. We show that there are regions in the map where an increase in the checkpoint inhibitor actually decreases the efficacy of the treatment. We also construct efficacy maps with checkpoint inhibitor vs. the replication potential of the virus that show the same antagonism, namely, an increase in the checkpoint inhibitor may actually decrease the efficacy. These results have implications for clinical trials. [ABSTRACT FROM AUTHOR]

In this paper we consider a combination therapy of cancer. One drug is a vaccine which activates dendritic cells so that they induce more T cells to infiltrate the tumor. The other drug is a checkpoint inhibitor, which enables the T cells to remain active against the cancer cells. The two drugs are positively correlated in the sense that an increase in the amount of each drug results in a reduction in the tumor volume. We consider the question whether a treatment with combination of the two drugs at certain levels is preferable to a treatment by one of the drugs alone at ‘roughly’ twice the dosage level; if that is the case, then we say that there is a positive ‘synergy’ for this combination of dosages. To address this question, we develop a mathematical model using a system of partial differential equations. The variables include dendritic and cancer cells, CD4+ and CD8+ T cells, IL-12 and IL-2, GM-CSF produced by the vaccine, and a T cell checkpoint inhibitor associated with PD-1. We use the model to explore the efficacy of the two drugs, separately and in combination, and compare the simulations with data from mouse experiments. We next introduce the concept of synergy between the drugs and develop a synergy map which suggests in what proportion to administer the drugs in order to achieve the maximum reduction of tumor volume under the constraint of maximum tolerated dose. [ABSTRACT FROM AUTHOR]

Background: Ginseng-containing traditional medicine preparations (G-TMPs) in combination with fluoropyrimidine-based chemotherapy (FBC) are well-known treatments for advanced gastric cancer (AGC), with a superior efficacy to FBC alone. However, evidence regarding their efficacy remains limited. The purpose of this meta-analysis is to evaluate the efficacy and safety of G-TMPs in combination with FBC for the treatment of AGC. Methods: Eight electronic databases were searched for randomized controlled trials (RCTs) using G-TMPs with FBC for the treatment of AGC. The primary outcome included the tumor response, while the secondary outcomes included the quality of life (QoL), proportions of peripheral blood lymphocytes, adverse drug reactions (ADRs), and levels of cancer biomarkers. The quality of evidence for each outcome was assessed using GRADE profilers. Results: A total of 1,960 participants were involved in the 26 RCTs included. Patients treated with FBC plus G-TMPs had better objective response (risk ratio [RR] = 1.23, 95% confidence interval [CI]: 1.13 to 1.35, p < 0.00001) and disease control (RR = 1.13, 95% CI: 1.08 to 1.19, p < 0.00001) rates than those treated with FBC alone. Additionally, the combination group had a better QoL, higher proportions of CD3+ T cells, CD4+ T cells, and natural killer cells, as well as a higher CD4+/CD8+ T-cell ratio. Furthermore, lower levels of CA19-9, CA72-4, and CEA were confirmed in the combination treatment group. In addition, G-TMPs reduced the incidence of ADRs during chemotherapy. Conclusion: In combination with FBC, G-TMPs can potentially enhance efficacy, reduce ADRs, and improve prognosis for patients with AGC. However, high-quality randomized studies remain warranted. Systematic review registration: PROSPERO Number: CRD42021264938. [ABSTRACT FROM AUTHOR]

Purpose: To assess the efficacy of combination chemotherapy with nafamostat mesilate, gemcitabine and S-1 for unresectable pancreatic cancer patients. Materials and methods: The study was conducted as a single-arm, single center, institutional review board-approved phase II trial. Patients received nafamosntat mesilate (4.8 mg/kg continuous transregional arterial infusion) with gemcitabine (1000 mg/m2 transvenous) on days 1 and15, and with oral S-1 [(80 mg/day (BSA<1.25 m2), 100 mg/day (1.25 ≤ BSA<1.5 m2), or 120 mg/day (BSA ≥1.5 m2)] on days 1–14 or, days 1–7 and 15–21. This regimen was repeated at 28-day intervals. Results: Forty-seven evaluable patients (Male/Female: 31/16, Age (median): 66 (range 35–78) yrs, Stage III/IV 10/37.) were candidates in this study. Two patients in stage III (20%) could undergo conversion surgery. Twenty-four patients (51%) underwent subsequent treatment (1st line/ 2nd line / 4th line, 13/ 10/ 1, FOLFIRINOX: 12, GEM/nab-PTX: 18, TAS-118: 3, chemoradiation with S-1: 2, GEM/Erlotinib: 1, nal-IRI: 1, surgery: 2). Median PFS and OS were 9.7 (95% CI, 8.9–14.7 mo) and 14.2 months (99% CI, 13.3–23.9 mo), respectively. Median PFS in stage IV patients was 9.2 months (95% CI, 8.4–12.0 mo). Median OS in patients without subsequent treatment was 10.8 months (95% CI, 9.1–13.8 mo). Median OS in patients with subsequent treatment was 19.3 months (95% CI, 18.9–31.9 mo). Grade 4 treatment-related hematological toxicities were encountered in 7 patients. Two patients developed grade 3 allergic reaction after 6 cycles or later. No febrile neutropenia has been observed. Conclusion: NAM/GEM/S-1 therapy is safe and could be promising option for unresectable pancreatic cancer, especially for stage IV cancer. [ABSTRACT FROM AUTHOR]

Background: Scaling up shorter regimens for tuberculosis (TB) prevention such as once weekly isoniazid-rifapentine (3HP) taken for 3 months is a key priority for achieving targets set forth in the World Health Organization's (WHO) END TB Strategy. However, there are few data on 3HP patient acceptance and completion in the context of routine HIV care in sub-Saharan Africa.Methods and Findings: The 3HP Options Trial is a pragmatic, parallel type 3 effectiveness-implementation randomized trial comparing 3 optimized strategies for delivering 3HP-facilitated directly observed therapy (DOT), facilitated self-administered therapy (SAT), or informed choice between DOT and SAT using a shared decision-making aid-to people receiving care at a large urban HIV clinic in Kampala, Uganda. Participants and healthcare providers were not blinded to arm assignment due to the nature of the 3HP delivery strategies. We conducted an interim analysis of participants who were enrolled and exited the 3HP treatment period between July 13, 2020 and April 30, 2021. The primary outcome, which was aggregated across trial arms for this interim analysis, was the proportion who accepted and completed 3HP (≥11 of 12 doses within 16 weeks of randomization). We used Bayesian inference analysis to estimate the posterior probability that this proportion would exceed 80% under at least 1 of the 3HP delivery strategies, a coprimary hypothesis of the trial. Through April 2021, 684 participants have been enrolled, and 479 (70%) have exited the treatment period. Of these 479 participants, 309 (65%) were women, mean age was 41.9 years (standard deviation (SD): 9.2), and mean time on antiretroviral therapy (ART) was 7.8 years (SD: 4.3). In total, 445 of them (92.9%, 95% confidence interval (CI): [90.2 to 94.9]) accepted and completed 3HP treatment. There were no differences in treatment acceptance and completion by sex, age, or time on ART. Treatment was discontinued due to a documented adverse event (AE) in 8 (1.7%) patients. The probability that treatment acceptance and completion exceeds 80% under at least 1 of the three 3HP delivery strategies was greater than 99%. The main limitations are that the trial was conducted at a single site, and the interim analysis focused on aggregate outcome data to maintain blinding of investigators to arm-specific outcomes.Conclusions: 3HP was widely accepted by people living with HIV (PLHIV) in Uganda, and very high levels of treatment completion were achieved in a programmatic setting. These findings show that 3HP can enable effective scale-up of tuberculosis preventive therapy (TPT) in high-burden countries, particularly when delivery strategies are tailored to target known barriers to treatment completion.Trial Registration: ClinicalTrials.gov NCT03934931. [ABSTRACT FROM AUTHOR]

The presence of autophagy has been indicated in cholangiocarcinoma (CC), which disease has poor prognosis and limited treatment options. Recently, CC has been classified by anatomical localization as intrahepatic (iCC), perihilar (pCC) and distal (dCC), showing different clinical and molecular characteristics. Thus, our aim was to compare autophagy activity in CC samples resected from different anatomical locations. Further, we investigated whether autophagy could be modulated in cell lines originated from iCC and extrahepatic CC (eCC) following the treatments with autophagy inhibitory and inducing agents. Tissue microarrays were prepared from 70 CC (28 iCC, 19 pCC and 23 dCC), 31 adjacent non-tumorous and 9 hepatocellular carcinoma (HCC) samples. Autophagy markers LC3, p62 and Beclin1 as well as proliferation marker Ki-67 were monitored by immunohistochemistry and were associated with patients' survival. Modulation of autophagy was investigated in cell lines originated from iCC (HuH-28), eCC (TFK-1) and HCC (HepG2) by treating the cells with chloroquine (CQ) for inhibition and with Rapamycin, 5-Fluorouracil (5-FU) and Sorafenib for induction of autophagy. Our results indicated an inhibited autophagy in iCC and pCC tumor tissues, whereas active autophagy seemed to occur in dCC, especially in samples displaying low Ki-67 index. Additionally, low level of Beclin1 and high level of Ki-67 were associated with poor overall survival in dCC, suggesting the prognostic role of these proteins in dCC. Beside a baseline autophagy detected in each cell line, Rapamycin and 5-FU induced autophagy in iCC and HepG2 cell lines, Sorafenib in iCC cells. A chemotherapy agent in combination with CQ decreased IC50 effectively in the cell lines where basal and/or induced autophagy were present. In conclusion, we revealed differences in the autophagy activities of CC tissues and cell lines originated from different anatomical locations, which might influence patients' treatment. Our results also suggest a prognostic role of Beclin1 and Ki-67 in dCC. [ABSTRACT FROM AUTHOR]

The novelty of new human coronavirus COVID-19/SARS-CoV-2 and the lack of effective drugs and vaccines gave rise to a wide variety of strategies employed to fight this worldwide pandemic. Many of these strategies rely on the repositioning of existing drugs that could shorten the time and reduce the cost compared to de novo drug discovery. In this study, we presented a new network-based algorithm for drug repositioning, called SAveRUNNER (Searching off-lAbel dRUg aNd NEtwoRk), which predicts drug–disease associations by quantifying the interplay between the drug targets and the disease-specific proteins in the human interactome via a novel network-based similarity measure that prioritizes associations between drugs and diseases locating in the same network neighborhoods. Specifically, we applied SAveRUNNER on a panel of 14 selected diseases with a consolidated knowledge about their disease-causing genes and that have been found to be related to COVID-19 for genetic similarity (i.e., SARS), comorbidity (e.g., cardiovascular diseases), or for their association to drugs tentatively repurposed to treat COVID-19 (e.g., malaria, HIV, rheumatoid arthritis). Focusing specifically on SARS subnetwork, we identified 282 repurposable drugs, including some the most rumored off-label drugs for COVID-19 treatments (e.g., chloroquine, hydroxychloroquine, tocilizumab, heparin), as well as a new combination therapy of 5 drugs (hydroxychloroquine, chloroquine, lopinavir, ritonavir, remdesivir), actually used in clinical practice. Furthermore, to maximize the efficiency of putative downstream validation experiments, we prioritized 24 potential anti-SARS-CoV repurposable drugs based on their network-based similarity values. These top-ranked drugs include ACE-inhibitors, monoclonal antibodies (e.g., anti-IFNγ, anti-TNFα, anti-IL12, anti-IL1β, anti-IL6), and thrombin inhibitors. Finally, our findings were in-silico validated by performing a gene set enrichment analysis, which confirmed that most of the network-predicted repurposable drugs may have a potential treatment effect against human coronavirus infections. Author summary: The global pandemic caused by the new coronavirus SARS-CoV-2 (COVID-19) leads a compelling need to find new therapeutic options devoted to fight the disease progression in the short term and to prevent it from happening in the future. The strategy of reusing an 'old drug' for new therapeutic purposes (known as drug repurposing) appears as a powerful solution for emerging diseases, such as COVID-19, since it allows to shorten the time and reduce the cost compared to de novo drug discovery. In this context, we propose SAveRUNNER (Searching off-lAbel dRUg aNd NEtwoRk), a new network-medicine-based algorithm for drug repurposing, with the aim to offer a promising framework to efficiently screen potential novel medical indications for various drugs, which are already approved and used in clinical practice, against the new human coronavirus (2019-nCoV/SARS-CoV-2). Our computational analysis predicts several repurposable drugs, including some of the most rumored off-label drugs for COVID-19 treatments as well as new promising candidates worthy of further exploration. [ABSTRACT FROM AUTHOR]

Objective: A current assessment of case reports of possible drug-induced pancreatitis is needed. We systematically reviewed the case report literature to identify drugs with potential associations with acute pancreatitis and the burden of evidence supporting these associations. Methods: A protocol was developed a priori (PROSPERO CRD42017060473). We searched MEDLINE, Embase, the Cochrane Library, and additional sources to identify cases of drug-induced pancreatitis that met accepted diagnostic criteria of acute pancreatitis. Cases caused by multiple drugs or combination therapy were excluded. Established systematic review methods were used for screening and data extraction. A classification system for associated drugs was developed a priori based upon the number of cases, re-challenge, exclusion of non-drug causes of acute pancreatitis, and consistency of latency. Results: Seven-hundred and thirteen cases of potential drug-induced pancreatitis were identified, implicating 213 unique drugs. The evidence base was poor: exclusion of non-drug causes of acute pancreatitis was incomplete or poorly reported in all cases, 47% had at least one underlying condition predisposing to acute pancreatitis, and causality assessment was not conducted in 81%. Forty-five drugs (21%) were classified as having the highest level of evidence regarding their association with acute pancreatitis; causality was deemed to be probable or definite for 19 of these drugs (42%). Fifty-seven drugs (27%) had the lowest level of evidence regarding an association with acute pancreatitis, being implicated in single case reports, without exclusion of other causes of acute pancreatitis. Discussion: Much of the case report evidence upon which drug-induced pancreatitis associations are based is tenuous. A greater emphasis on exclusion of all non-drug causes of acute pancreatitis and on quality reporting would improve the evidence base. It should be recognized that reviews of case reports, are valuable scoping tools but have limited strength to establish drug-induced pancreatitis associations. Registration: CRD42017060473. [ABSTRACT FROM AUTHOR]

The development of chemotherapies against eukaryotic pathogens is especially challenging because of both the evolutionary conservation of drug targets between host and parasite, and the evolution of strain-dependent drug resistance. There is a strong need for new nontoxic drugs with broad-spectrum activity against trypanosome parasites such as Leishmania and Trypanosoma. A relatively untested approach is to target macromolecular interactions in parasites rather than small molecular interactions, under the hypothesis that the features specifying macromolecular interactions diverge more rapidly through coevolution. We computed tRNA Class-Informative Features in humans and independently in eight distinct clades of trypanosomes, identifying parasite-specific informative features, including base pairs and base mis-pairs, that are broadly conserved over approximately 250 million years of trypanosome evolution. Validating these observations, we demonstrated biochemically that tRNA:aminoacyl-tRNA synthetase (aaRS) interactions are a promising target for anti-trypanosomal drug discovery. From a marine natural products extract library, we identified several fractions with inhibitory activity toward Leishmania major alanyl-tRNA synthetase (AlaRS) but no activity against the human homolog. These marine natural products extracts showed cross-reactivity towards Trypanosoma cruzi AlaRS indicating the broad-spectrum potential of our network predictions. We also identified Leishmania major threonyl-tRNA synthetase (ThrRS) inhibitors from the same library. We discuss why chemotherapies targeting multiple aaRSs should be less prone to the evolution of resistance than monotherapeutic or synergistic combination chemotherapies targeting only one aaRS. Author summary: Trypanosome parasites pose a significant health risk worldwide. Conventional drug development strategies have proven challenging given the high conservation between humans and pathogens, with off-target toxicity being a common problem. Protein synthesis inhibitors have historically been an attractive target for antimicrobial discovery against bacteria, and more recently for eukaryotic pathogens. Here we propose that exploiting pathogen-specific tRNA-synthetase interactions offers the potential for highly targeted drug discovery. To this end, we improved tRNA gene annotations in trypanosome genomes, identified functionally informative trypanosome-specific tRNA features, and showed that these features are highly conserved over approximately 250 million years of trypanosome evolution. Highlighting the species-specific and broad-spectrum potential of our approach, we identified natural product inhibitors against the parasite translational machinery that have no effect on the homologous human enzyme. [ABSTRACT FROM AUTHOR]

Most HIV-infected patients who initiate combination antiretroviral therapy experience a viral load decline in several phases. These phases are characterized by different rates of viral load decay that decrease when transitioning from one phase to the next. There is no consensus as to the origin of these phases. One hypothesis put forward is that short- and long-lived infected cells are responsible for the first and second phases of decay, respectively. However, significant differences in drug concentrations are observed in monocytes from various tissues, suggesting the first two phases of decay in viral loads could instead be attributed to short-lived cells being differently exposed to drugs. Compared to a well-exposed compartment, new cell infection can be expected in a compartment with limited drug exposure, thus leading to a slower viral load decay with potential virologic failure and drug resistance. In the current study, the latter hypothesis was investigated using a model of viral kinetics. Empirical datasets were involved in model elaboration and parameter estimation. In particular, susceptibility assay data was used for an in vitro to in vivo extrapolation based on the expected drug concentrations inside physiological compartments. Results from numerical experiments of the short-term evolution of viral loads can reproduce the first two phases of viral decay when allowing new short-lived cell infections in an unidentified drug-limited compartment. Model long-term predictions are however less consistent with clinical observations. For the hypothesis to hold, efavirenz, tenofovir and emtricitabine drug exposure in the drug-limited compartment would have to be very low compared to exposure in peripheral blood. This would lead to significant long-term viral growth and the frequent development of resistant strains, a prediction not supported by clinical observations. This suggests that the existence of a drug-limited anatomical compartment is unlikely, by itself, to explain the second phase of viral load decay. [ABSTRACT FROM AUTHOR]

Background: Retention in anti-retroviral therapy (ART) presents a challenge in sub-Saharan Africa. In Mozambique, after roll-out to peripheral facilities, the 12-month retention rate was reported mostly from sites with an electronic patient tracking system (EPTS), representing only 65% of patients. We conducted a nationally representative study, compared 12-month retention at EPTS and non-EPTS sites, and its predictors. Methods: Applying a proportionate to population size sampling strategy, we obtained a nationally representative sample of patients who initiated ART between January 2013 and June 2014. We calculated weighted proportions of the patients’ status at 12 months after ART initiation, and 12-month incidence of lost to follow-up (LTFU) and death. We assessed determinants of LTFU and death by calculating adjusted hazard ratios (AHR) through multivariate cox-proportional hazard models. Results: Among 19,297 patients sampled, 54.3% were still active, 33.1% LTFU, 2.0% dead, 2.6% transferred-out and 8.0% had unknown status, 12 months after ART initiation. Total attrition rate (LTFU or dead) was 45.5/100PY, higher at facilities without EPTS (51.8/100PY) than with EPTS (37.7/100PY). Clinical stage IV (AHR = 1.7), CD4 count ≤150 (AHR = 1.3) and being pregnant (AHR = 1.6) were significantly associated with LTFU. Clinical stage III or IV (AHR = 2.1 and 3.8), CD4 count ≤150 (AHR = 3.0), not being pregnant (AHR = 3.0), and ART regimens with stavudine (AHR = 4.28) were significantly associated with deaths. Patients enrolled in adherence support groups were 4.6 times less likely to be LTFU, but the number (n = 174) was too small to be significant (p = 0.273). Conclusion: Retention in ART was substantially lower at non-EPTS sites. EPTS should be expanded to all ART sites to facilitate comprehensive routine monitoring of retention in care. Retention in Mozambique is low and needs to be improved, especially among pregnant women and patients with advanced disease at ART initiation. The effect of ART adherence support groups needs to be further monitored. [ABSTRACT FROM AUTHOR]

Background: Tafenoquine is an investigational 8-aminoquinoline for the prevention of Plasmodium vivax relapse. Tafenoquine has a long half-life and the potential for more convenient dosing, compared with the currently recommended 14-day primaquine regimen. Methods: This randomized, active-control, double-blind trial was conducted in Bangkok, Thailand. Seventy patients with microscopically confirmed P. vivax were randomized (2:1) to tafenoquine 400 mg once daily for 3 days or 2500 mg total dose chloroquine phosphate (1500 mg chloroquine base) given over 3 days plus primaquine 15 mg daily for 14 days. Patients were followed to day 120. Results: Day 28 adequate clinical response rate in the per-protocol population was 93% (40/43) (90%CI 83–98%) with tafenoquine, and 100% (22/22) (90%CI 87–100%) with chloroquine/primaquine. Day 120 relapse prevention was 100% (35/35) with tafenoquine (90%CI 92–100%), and 95% (19/20) (90%CI 78–100%) with chloroquine/primaquine. Mean (SD) parasite, gametocyte and fever clearance times with tafenoquine were 82.5 h (32.3), 49.1 h (33.0), and 41.1 h (31.4) versus 40.0 h (15.7), 22.7 h (16.4), and 24.7 h (17.7) with chloroquine/primaquine, respectively. Peak methemoglobin was 1.4–25.6% (median 7.4%, mean 9.1%) in the tafenoquine arm, and 0.5–5.9% (median 1.5%, mean 1.9%) in the chloroquine/primaquine arm. There were no clinical symptoms of methemoglobinemia in any patient. Discussion: Although there was no difference in efficacy in this study, the slow rate of parasite, gametocyte and fever clearance indicates that tafenoquine should not be used as monotherapy for radical cure of P. vivax malaria. Also, monotherapy increases the potential risk of resistance developing to this long-acting agent. Clinical trials of single-dose tafenoquine 300 mg combined with standard 3-day chloroquine or artemisinin-based combination therapy are ongoing. Trial registration: Clinicaltrials.gov [ABSTRACT FROM AUTHOR]

Tumor-induced angiogenesis leads to the development of leaky tumor vessels devoid of structural and morphological integrity. Due to angiogenesis, elevated interstitial fluid pressure (IFP) and low blood perfusion emerge as common properties of the tumor microenvironment that act as barriers for drug delivery. In order to overcome these barriers, normalization of vasculature is considered to be a viable option. However, insight is needed into the phenomenon of normalization and in which conditions it can realize its promise. In order to explore the effect of microenvironmental conditions and drug scheduling on normalization benefit, we build a mathematical model that incorporates tumor growth, angiogenesis and IFP. We administer various theoretical combinations of antiangiogenic agents and cytotoxic nanoparticles through heterogeneous vasculature that displays a similar morphology to tumor vasculature. We observe differences in drug extravasation that depend on the scheduling of combined therapy; for concurrent therapy, total drug extravasation is increased but in adjuvant therapy, drugs can penetrate into deeper regions of tumor. [ABSTRACT FROM AUTHOR]

The radix of Scutellaria baicalensis (SB) is a herb widely used in traditional Chinese medicine to treat metabolic diseases. Several main components, including baicalin and wogonoside, possess anti-dyslipidemia, anti-obesity and anti-diabetic effects. We hypothesized that co-administration of SB extract and metformin exerts a better effect on obesity-induced insulin resistance and lipid metabolism than treatment with metformin alone. We compared the effect of metformin (100 mg/10 mL/kg/day) alone with co-administration of metformin (100 mg/5 mL/kg/day) and SB extract (200 mg/5 mL/kg/day) on Otsuka Long Evans Tokushima Fatty rats, a useful model of type II diabetes with obesity, and used Long-Evans Tokushima Otsuka rats as a control. Weight, fasting glucose, oral glucose tolerance test, intraperitoneal insulin tolerance test, and serum total cholesterol were measured after 12 weeks of drug administration. We observed a synergetic effect of metformin and SB on lowering cholesterol level by excretion of bile acid through feces. We found that this accompanied activation of FXR, CYP7A1 and LDLR genes and repression of HMGCR in the liver. Although there were no significant changes in BSH-active gut microbiota due to high variability, functional prediction with 16S sequences showed increased primary and secondary bile acid biosynthesis in the combination treatment group. Further study is needed to find the specific strains of bacteria which contribute to FXR-related cholesterol and bile acid regulations. [ABSTRACT FROM AUTHOR]

Background: AmBisome therapy for VL has an excellent efficacy and safety profile and has been adopted as a first-line regimen in Bangladesh. Second-line treatment options are limited and should preferably be given in short course combinations in order to prevent the development of resistant strains. Combination regimens including AmBisome, paromomycin and miltefosine have proved to be safe and effective in the treatment of VL in India. In the present study, the safety and efficacy of these same combinations were assessed in field conditions in Bangladesh. Methods: The safety and efficacy of three combination regimens: a 5 mg/kg single dose of AmBisome + 7 subsequent days of miltefosine (2.5 mg/kg/day), a 5 mg/kg single dose of AmBisome + 10 subsequent days of paromomycin (15 mg/kg/day) and 10 days of paromomycin (15 mg/kg/day) + miltefosine (2.5 mg/kg/day), were compared with a standard regimen of AmBisome 15 mg/kg given in 5 mg/kg doses on days 1, 3 and 5. This was a phase III open label, individually randomized clinical trial. Patients from 5 to 60 years with uncomplicated primary VL were recruited from the Community Based Medical College Bangladesh (CBMC,B) and the Upazila Health Complexes of Trishal, Bhaluka and Fulbaria (all located in Mymensingh district), and randomly assigned to one of the treatments. The objective was to assess safety and definitive cure at 6 months after treatment. Results: 601 patients recruited between July 2010 and September 2013 received either AmBisome monotherapy (n = 158), AmBisome + paromomycin (n = 159), AmBisome + miltefosine (n = 142) or paromomycin + miltefosine (n = 142). At 6 months post- treatment, final cure rates for the intention-to-treat population were 98.1% (95%CI 96.0–100) for AmBisome monotherapy, 99.4% (95%CI 98.2–100) for the AmBisome + paromomycin arm, 94.4% (95%CI 90.6–98.2) for the AmBisome + miltefosine arm, and 97.9% (95%CI 95.5–100) for paromomycin + miltefosine arm. There were 12 serious adverse events in the study in 11 patients that included 3 non-study drug related deaths. There were no relapses or PKDL up to 6 months follow-up. All treatments were well tolerated with no unexpected side effects. Adverse events were most frequent during treatment with miltefosine + paromomycin, three serious adverse events related to the treatment occurred in this arm, all of which resolved. Conclusion: None of the combinations were inferior to AmBisome in both the intention-to-treat and per-protocol populations. All the combinations demonstrated excellent overall efficacy, were well tolerated and safe, and could be deployed under field conditions in Bangladesh. The trial was conducted by the International Centre for Diarrhoeal Disease Research (ICDDR,B) and the Shaheed Suhrawardy Medical College (ShSMC), Dhaka, in collaboration with the trial sites and sponsored by the Drugs for Neglected Diseases initiative (DNDi). Trial registration: ClinicalTrials.gov [ABSTRACT FROM AUTHOR]

Background: Recent efforts in malaria control have resulted in great gains in reducing the burden of Plasmodium falciparum, but P. vivax has been more refractory. Its ability to form dormant liver stages confounds control and elimination efforts. To compare the efficacy and safety of primaquine regimens for radical cure, we undertook a randomized controlled trial in Ethiopia.Methods and Findings: Patients with normal glucose-6-phosphate dehydrogenase status with symptomatic P. vivax mono-infection were enrolled and randomly assigned to receive either chloroquine (CQ) or artemether-lumefantrine (AL), alone or in combination with 14 d of semi-supervised primaquine (PQ) (3.5 mg/kg total). A total of 398 patients (n = 104 in the CQ arm, n = 100 in the AL arm, n = 102 in the CQ+PQ arm, and n = 92 in the AL+PQ arm) were followed for 1 y, and recurrent episodes were treated with the same treatment allocated at enrolment. The primary endpoints were the risk of P. vivax recurrence at day 28 and at day 42. The risk of recurrent P. vivax infection at day 28 was 4.0% (95% CI 1.5%-10.4%) after CQ treatment and 0% (95% CI 0%-4.0%) after CQ+PQ. The corresponding risks were 12.0% (95% CI 6.8%-20.6%) following AL alone and 2.3% (95% CI 0.6%-9.0%) following AL+PQ. On day 42, the risk was 18.7% (95% CI 12.2%-28.0%) after CQ, 1.2% (95% CI 0.2%-8.0%) after CQ+PQ, 29.9% (95% CI 21.6%-40.5%) after AL, and 5.9% (95% CI 2.4%-13.5%) after AL+PQ (overall p < 0.001). In those not prescribed PQ, the risk of recurrence by day 42 appeared greater following AL treatment than CQ treatment (HR = 1.8 [95% CI 1.0-3.2]; p = 0.059). At the end of follow-up, the incidence rate of P. vivax was 2.2 episodes/person-year for patients treated with CQ compared to 0.4 for patients treated with CQ+PQ (rate ratio: 5.1 [95% CI 2.9-9.1]; p < 0.001) and 2.3 episodes/person-year for AL compared to 0.5 for AL+PQ (rate ratio: 6.4 [95% CI 3.6-11.3]; p < 0.001). There was no difference in the occurrence of adverse events between treatment arms. The main limitations of the study were the early termination of the trial and the omission of haemoglobin measurement after day 42, resulting in an inability to estimate the cumulative risk of anaemia.Conclusions: Despite evidence of CQ-resistant P. vivax, the risk of recurrence in this study was greater following treatment with AL unless it was combined with a supervised course of PQ. PQ combined with either CQ or AL was well tolerated and reduced recurrence of vivax malaria by 5-fold at 1 y.Trial Registration: ClinicalTrials.gov NCT01680406. [ABSTRACT FROM AUTHOR]

Introduction: Conservative treatment solutions against aortic prosthetic vascular graft infection (APVGI) for inoperable patients are limited. The combination of antibiotics with antibacterial helper compounds, such as the neuroleptic drug thioridazine (TDZ), should be explored. Aim: To investigate the efficacy of conservative systemic treatment with dicloxacillin (DCX) in combination with TDZ (DCX+TDZ), compared to DCX alone, against early APVGI caused by methicillin-sensitive Staphylococcus aureus (MSSA) in a porcine model. Methods: The synergism of DCX+TDZ against MSSA was initially assessed in vitro by viability assay. Thereafter, thirty-two pigs had polyester grafts implanted in the infrarenal aorta, followed by inoculation with 106 CFU of MSSA, and were randomly administered oral systemic treatment with either 1) DCX or 2) DCX+TDZ. Treatment was initiated one week postoperatively and continued for a further 21 days. Weight, temperature, and blood samples were collected at predefined intervals. By termination, bacterial quantities from the graft surface, graft material, and perigraft tissue were obtained. Results: Despite in vitro synergism, the porcine experiment revealed no statistical differences for bacteriological endpoints between the two treatment groups, and none of the treatments eradicated the APVGI. Accordingly, the mixed model analyses of weight, temperature, and blood samples revealed no statistical differences. Conclusion: Conservative systemic treatment with DCX+TDZ did not reproduce in vitro results against APVGI caused by MSSA in this porcine model. However, unexpected severe adverse effects related to the planned dose of TDZ required a considerable reduction to the administered dose of TDZ, which may have compromised the results. [ABSTRACT FROM AUTHOR]

Introduction: To demonstrate that preoperative treatment for 28 days with topical dorzolamide/timolol is non-inferior (Δ = 4 mm Hg) to oral acetazolamide and topical dexamethasone (standard therapy) in terms of intraocular pressure (IOP) reduction 3 and 6 months after trabeculectomy in glaucoma patients. Materials and methods: Sixty-two eyes undergoing trabeculectomy with mitomycin C were included in this monocentric prospective randomized controlled study. IOP change between baseline and 3 months post-op was defined as the primary efficacy variable. Secondary efficacy variables included the number of 5-fluorouracil (5-FU) injections, needlings, suture lyses, preoperative IOP change, hypertension rate and change of conjunctival redness 3 and 6 months post-op. Safety was assessed based on the documentation of adverse events. Results: Preoperative treatment with topical dorzolamide/timolol was non-inferior to oral acetazolamide and topical dexamethasone in terms of IOP reduction 3 months after trabeculectomy (adjusted means -8.12 mmHg versus -8.30 mmHg; Difference: 0.18; 95% CI -1.91 to 2.26, p = 0.8662). Similar results were found 6 months after trabeculectomy (-9.13 mmHg versus -9.06 mmHg; p = 0.9401). Comparable results were also shown for both groups concerning the classification of the filtering bleb, corneal staining, and numbers of treatments with 5-FU, needlings and suture lyses. More patients reported AEs in the acetazolamide/dexamethasone group than in the dorzolamide/timolol group. Discussion: Preoperative, preservative-free, fixed-dose dorzolamide/timolol seems to be equally effective as preoperative acetazolamide and dexamethasone and has a favourable safety profile. [ABSTRACT FROM AUTHOR]

Objectives: Warfarin oral anticoagulant therapy (OAT) requires regular and frequent drug adjustment monitored by INR. Interindividual variability, drug and diet interferences, and genetics (VKORC1 and CYP2C9) make the maintenance/reaching of stable INR a not so easy task. HPLC assessment of warfarin/enantiomers was suggested as a valid monitoring-tool along with INR, but definite results are still lacking. We evaluated possible correlations between INR, warfarin/3’-hydroxywarfarin, and drug weekly dosage aimed at searching novel alternatives to OAT monitoring. VKORC1/CYP2C9 pharmacogenetics investigation was performed to account for the known influence on warfarin homeostasis. Methods: 133 OAT patients were recruited and assessed for warfarin/3’-hydroxywarfarin serum levels (HPLC), INR, and VKORC1 and CYP2C9 genotypes. A subgroup of 52 patients were monitored in detail (5 consecutive controls; c0-c4) till the target INR was reached. Correlation analyses were performed in both groups Results: In the whole OAT group both warfarin and 3’-hydroxywarfarin correlate with INR at comparable degree (r2 = 0.0388 and 0.0362 respectively). Conversely, warfarin weekly dosage better correlates with warfarin than with 3’-hydroxywarfarin (r2 = 0.0975 and r2 = 0.0381 respectively), but considering together warfarin plus 3’-hydroxywarfarin the correlation strongly increased (r2 = 0.1114; p<0.0001). Interestingly, 3’-hydroxywarfarin reached a strong correlation at c4 respect to warfarin (r2 = 0.2157 and r2 = 0.0549; p = 0.0005 and p = 0.0944 respectively) seeming less affected by drug adjustments in the subgroup of 52 patients who started OAT. The multivariate analyses aimed at estimating the true contribution of 3’-hydroxywarfarin on INR value ascribed it the unique significant value (p = 0.0021) in spite of warfarin who lost association. The pharmacogenetics studies confirmed that patients carrying the VKORC1 variant-allele required lower warfarin maintenance dosage and that the combination of VKORC1 and CYP2C9 yielded a warfarin responsive index (WRI) inversely related to the number variant alleles Conclusion: Our results overall suggest that 3’-hydroxywarfarin monitoring could be of great advantage in INR monitoring respect to classical warfarin assessment showing significant contribution also in multivariate analysis. Therefore, additional active metabolites should be recognized and investigated as novel useful indicators. [ABSTRACT FROM AUTHOR]

Background: In February 2011, an Ohio law took effect mandating use of the United States Food and Drug Administration (FDA)-approved protocol for mifepristone, which is used with misoprostol for medication abortion. Other state legislatures have passed or enacted similar laws requiring use of the FDA-approved protocol for medication abortion. The objective of this study is to examine the association of this legal change with medication abortion outcomes and utilization.Methods and Findings: We used a retrospective cohort design, comparing outcomes of medication abortion patients in the prelaw period to those in the postlaw period. Sociodemographic and clinical chart data were abstracted from all medication abortion patients from 1 y prior to the law's implementation (January 2010-January 2011) to 3 y post implementation (February 2011-October 2014) at four abortion-providing health care facilities in Ohio. Outcome data were analyzed for all women undergoing abortion at ≤49 d gestation during the study period. The main outcomes were as follows: need for additional intervention following medication abortion (such as aspiration, repeat misoprostol, and blood transfusion), frequency of continuing pregnancy, reports of side effects, and the proportion of abortions that were medication abortions (versus other abortion procedures). Among the 2,783 medication abortions ≤49 d gestation, 4.9% (95% CI: 3.7%-6.2%) in the prelaw and 14.3% (95% CI: 12.6%-16.0%) in the postlaw period required one or more additional interventions. Women obtaining a medication abortion in the postlaw period had three times the odds of requiring an additional intervention as women in the prelaw period (adjusted odds ratio [AOR] = 3.11, 95% CI: 2.27-4.27). In a mixed effects multivariable model that uses facility-months as the unit of analysis to account for lack of independence by site, we found that the law change was associated with a 9.4% (95% CI: 4.0%-18.4%) absolute increase in the rate of requiring an additional intervention. The most common subsequent intervention in both periods was an additional misoprostol dose and was most commonly administered to treat incomplete abortion. The percentage of women requiring two or more follow-up visits increased from 4.2% (95% CI: 3.0%-5.3%) in the prelaw period to 6.2% (95% CI: 5.5%-8.0%) in the postlaw period (p = 0.003). Continuing pregnancy was rare (0.3%). Overall, 12.6% of women reported at least one side effect during their medication abortion: 8.4% (95% CI: 6.8%-10.0%) in the prelaw period and 15.6% (95% CI: 13.8%-17.3%) in the postlaw period (p < 0.001). Medication abortions fell from 22% (95% CI: 20.8%-22.3%) of all abortions the year before the law went into effect (2010) to 5% (95% CI: 4.8%-5.6%) 3 y after (2014) (p < 0.001). The average patient charge increased from US$426 in 2010 to US$551 in 2014, representing a 16% increase after adjusting for inflation in medical prices. The primary limitation to the study is that it was a pre/post-observational study with no control group that was not exposed to the law.Conclusions: Ohio law required use of a medication abortion protocol that is associated with a greater need for additional intervention, more visits, more side effects, and higher costs for women relative to the evidence-based protocol. There is no evidence that the change in law led to improved abortion outcomes. Indeed, our findings suggest the opposite. In March 2016, the FDA-protocol was updated, so Ohio providers may now legally provide current evidence-based protocols. However, this law is still in place and bans physicians from using mifepristone based on any new developments in clinical research as best practices continue to be updated. [ABSTRACT FROM AUTHOR]

Background: Medulloblastoma (MB) is the most common pediatric primary malignant brain tumor. Approximately one-third of MB patients succumb to treatment failure and some survivors suffer detrimental side effects. Hence, the purpose of this study is to explore new therapeutic regimens to overcome chemotherapeutic agent resistance or reduce chemotherapy-induced toxicity. Methods: We detected the expression of inhibitors of apoptosis proteins (IAPs) in MB and CD133+ MB cell lines and MB tissues using immunoblotting and immunohistochemical staining. The antitumor effects of inhibitors against IAPs on MB or CD133+ MB cells were evaluated by MTT assay, Annexin V/PI analysis, and caspase-3/7 activity. Autophagy was assessed by the conversion of light chain (LC) 3-I to LC3-II and Cyto-ID autophagy detection kit. Results: MB cells showed higher expression of IAPs compared to normal astrocytes and normal brain tissues. Conventional chemotherapeutic agents combined with small-molecule IAP inhibitors (LCL161 or LBW242) showed a synergistic effect in MB cells. Combined treatments triggered apoptosis in MB cells through activation of caspase-3/7 and autophagic flux simultaneously. In addition, we found that CD133+ MB cells with features of cancer stem cells displayed higher levels of X-linked inhibitor of apoptosis (XIAP) and cellular inhibitor of apoptosis 1/2 (cIAP1/2), and were hypersensitive to treatment with IAP inhibitors. Conclusions: These results shed light on the biological effects of combination therapy on MB cells and illustrate that IAP inhibitors are more effective for CD133+ stem-like MB cells. [ABSTRACT FROM AUTHOR]

Introduction: Current treatment options for advanced esophagogastric cancer (AEGC) are still unsatisfactory. The aim of this prospective phase Ib/II study was to evaluate the safety and efficacy of a novel regimen, AVDCX, consisting of weekly docetaxel and cisplatin together with capecitabine and bevacizumab, in AEGC. Methods: Patients with AEGC received treatment with different dose levels of AVDCX (cisplatin and docetaxel 25–35 mg/m2, days 1,8, capecitabine 1,600 mg/m2 days 1–14, bevacizumab 7.5 mg/kg, day 1, Q:21 days). The study's primary objectives were to establish the recommended phase II doses of docetaxel and cisplatin in AVDCX (phase Ib part) and to determine the tumor response rate (phase II part). Results: The study was closed early, after the accrual of 22 patients, due to accumulating toxicity-related deaths. The median age was 59 years and 77% of patients had gastric or gastroesophageal adenocarcinomas. Grade ≥3 adverse events were documented in 18 patients (82%), usually neutropenia (36%), fatigue (54%) or diarrhea (23%). There were three fatal toxicities (14%): mesenteric thromboembolism, gastric perforation and pancytopenic sepsis. The recommended phase II doses of cisplatin and docetaxel were determined to be 25 mg/m2 and 30 mg/m2, respectively. Twenty-one patients were evaluable for response: 12 (54%) had partial response (PR), 4 (18%) had stable disease (SD) and none had complete response (CR). Hence, the objective response rate (CR+PR) was 54% and the disease control rate (CR+PR+SD) was 72%. For the 17 patients treated at the MTD, the objective response rate was 41% and the disease control rate was 88%. The median overall survival (OS) for these patients was 13.9 months (range, 1.5–52.2 months) and the median progression-free survival was 7.6 months (range, 1.3–26.6 months). The 2-year OS rate reached 23.7%. Conclusions: AVDCX was associated with a high rate of regimen related fatal adverse events and is not appropriate for further development in AEGC patients. Trial Registration: ClinicalTrials.gov , [ABSTRACT FROM AUTHOR]

Clinical studies using definitive-intent stereotactic radiation therapy (SRT) for the local treatment of canine osteosarcoma (OSA) have shown canine patients achieving similar median survival times as the current standard of care (amputation and adjuvant chemotherapy). Despite this, there remains an unacceptable high risk of pathologic fracture following radiation treatment. Zoledronic acid (ZA) and parathyroid hormone (PTH) are therapeutic candidates for decreasing this fracture risk post-irradiation. Due to differing mechanisms, we hypothesized that the combined treatment with ZA and PTH would significantly improve bone healing more than ZA or PTH treatment alone. Using an orthotopic model of canine osteosarcoma in athymic rats, we evaluated bone healing following clinically-relevant doses of radiation therapy (12 Gy x 3 fractions, 36 Gy total). Groups included 36 Gy SRT only, 36 Gy SRT plus ZA, 36 Gy SRT plus ZA and PTH, 36 Gy SRT plus PTH, and 36 Gy SRT plus localized PTH treatment. Our study showed significant increases in bone volume and increased polar moments of inertia (in the distal femoral metaphysis) 8 weeks after radiation in the combined (ZA/PTH) treatment group as compared to radiation treatment alone. Histomorphometric analysis revealed evidence of active mineralization at the study endpoint as well as successful tumor-cell kill across all treatment groups. This work provides further evidence for the expanding potential indications for ZA and PTH therapy, including post-irradiated bone disease due to osteosarcoma. [ABSTRACT FROM AUTHOR]

Background: Several reports of chloroquine treatment failure and resistance in Plasmodium vivax malaria from Southeast Asian countries have been published. Present study was undertaken to assess the efficacy of chloroquine-primaquine (CQ-PQ) combined regimen for the treatment of P. vivax malaria patients who were catered by the selected primary health centres (PHCs) of Udupi taluk, Udupi district, Karnataka, India. Method: Five PHCs were selected within Udupi taluk based on probability proportional to size. In-vivo therapeutic efficacy assessment of CQ (1500 mg over three days) plus PQ (210 mg over 14 days) regimen was carried out in accordance with the World Health Organization’s protocol of 28 days follow-up among microscopically diagnosed monoinfection P. vivax cohort. Results: In total, 161 participants were recruited in the study of which, 155 (96.3%) participants completed till day 28 follow-up, fully complied with the treatment regimen and showed adequate clinical and parasitological response. Loss to follow up was noted with 5 (3.1%) participants and non-compliance with treatment regimen occurred with one participant (0.6%). Glucose-6-phosphate dehydrogenase deficiency (G6PDd, <30% of normal mean activity) was noted among 5 (3.1%) participants and one of them did develop PQ induced dark-brown urination which subsided after PQ discontinuation. G6PDd patients were treated with PQ 45 mg/week for eight weeks while PQ was discontinued in one case with G6PD 1.4 U/g Hb due to complaint of reddish-brown coloured urine by 48 hours of PQ initiation. Nested polymerase chain reaction test revealed 45 (28%) cases as mixed (vivax and falciparum) malaria. Conclusions: The CQ-PQ combined regimen remains outstandingly effective to treat uncomplicated P. vivax malaria in Udupi taluk and thus it should continue as first line regimen. For all P. vivax cases, G6PD screening before PQ administration must be mandatory and made available in all PHCs. [ABSTRACT FROM AUTHOR]

The ability of Natural Killer (NK) cells to kill tumor targets has been extensively studied in various hematological malignancies. However, NK cell therapy directed against solid tumors is still in early development. Epidermal Growth Factor Receptor (EGFR) targeted therapies using monoclonal antibodies (mAbs) such as cetuximab and panitumumab are widely used for the treatment of metastatic colorectal cancer (mCRC). Still, the clinical efficacy of this treatment is hampered by mutations in RAS gene, allowing tumors to escape from anti-EGFR mAb therapy. It is well established that NK cells kill tumor cells by natural cytotoxicity and can in addition be activated upon binding of IgG1 mAbs through Fc receptors (CD16/FcγRIIIa) on their surface, thereby mediating antibody dependent cellular cytotoxicity (ADCC). In the current study, activated Peripheral Blood NK cells (PBNK) were combined with anti-EGFR mAbs to study their effect on the killing of EGFR+/- cancer cell lines, including those with RAS mutations. In vitro cytotoxicity experiments using colon cancer primary tumors and cell lines COLO320, Caco-2, SW620, SW480 and HT-29, demonstrated that PBNK cells are cytotoxic for a range of tumor cells, regardless of EGFR, RAS or BRAF status and at low E:T ratios. Cetuximab enhanced the cytotoxic activity of NK cells on EGFR+ tumor cells (either RASwt, RASmut or BRAFmut) in a CD16 dependent manner, whereas it could not increase the killing of EGFR- COLO320. Our study provides a rationale to strengthen NK cell immunotherapy through a combination with cetuximab for RAS and BRAF mutant mCRC patients. [ABSTRACT FROM AUTHOR]

Few effective therapeutic options are available for treating severe infections caused by extensively drug-resistant Acinetobacter baumannii (XDR-AB). Using a murine thigh-infection model, we examined the in vivo efficacy of colistin in combination with meropenem, tigecycline, fosfomycin, fusidic acid, rifampin, or sulbactam against 12 XDR-AB strains. Colistin, tigecycline, rifampin, and sulbactam monotherapy significantly decreased bacterial counts in murine thigh infections compared with those observed in control mice receiving no treatment. Colistin was the most effective agent tested, displaying bactericidal activity against 91.7% of strains at 48 h post-treatment. With strains showing a relatively low minimum inhibitory concentration (MIC) for meropenem (MIC ≤ 32 mg/L), combination therapy with colistin plus meropenem caused synergistic inhibition at both 24 h and 48 h post-treatment. However, when the meropenem MIC was ≥64 mg/L, meropenem did not significantly alter the efficacy of colistin. The addition of rifampin and fusidic acid significantly improved the efficacy of colistin, showing a synergistic effect in 100% and 58.3% of strains after 24 h of treatment, respectively, while the addition of tigecycline, fosfomycin, or sulbactam did not show obvious synergistic activity. No clear differences in activities were observed between colistin-rifampin and colistin-fusidic acid combination therapy with most strains. Overall, our in vivo study showed that administering colistin in combination with rifampin or fusidic acid is more efficacious in treating XDR-AB infections than other combinations. The colistin-meropenem combination may be another appropriate option if the MIC is ≤32 mg/L. Further clinical studies are urgently needed to confirm the relevance of these findings. [ABSTRACT FROM AUTHOR]

Background: Patients with metastatic sarcoma who progress on vascular endothelial growth factor receptor inhibitors (VEGFRi) have limited treatment options. Upregulation of the mTOR pathway has been demonstrated to be a means of resistance to targeted VEGFRi in metastatic sarcoma. Patients and methods: Retrospective cohort study to evaluate the clinical benefit at four months of combining mTOR inhibition (mTORi) via everolimus with VEGFRi in patients who have derived benefit from single-agent VEGFRi but have progressed. Patients with recurrent, metastatic soft tissue or bone sarcomas who progressed after deriving clinical benefit to VEGFRi beyond 12 weeks were continued on VEGFRi with the addition of everolimus (5 mg daily). Progression free survival was measured from start of VEGFRi to disease progression on single agent VEGFRi as well as from the addition of everolimus therapy to disease progression or drug discontinuation due to toxicity. Clinical benefit was defined as stable disease or partial response at 4 months. Results: Nine patients were evaluated. Two patients did not tolerate therapy due to GI toxicity and one elected to discontinue therapy. Of the remaining six patients, the clinical benefit rate at four months was 50%. Progression free survival (PFS) for these patients was 3.1 months ranging from 0.5 to 7.2 months with one patient remaining on combination therapy. Conclusion: In this heavily pre-treated, advanced sarcoma population, the addition of mTOR inhibition to VEGFRi based therapy resulted in a clinical benefit for a subset of patients. Prospective studies will be needed to verify these results. [ABSTRACT FROM AUTHOR]

Background: As per the WHO recommendation, the development of resistance by P. falciparum to most artemisinin combination therapies (ACTs) triggered the need for routine monitoring of the efficacy of the drugs every two years in all malaria endemic countries. Hence, this study was carried out to assess the therapeutic efficacy of Artemether-Lumefantrine (Coartem®) in treating the uncomplicated falciparum malaria, after 9 years of its introduction in the Metehara, Eastern Ethiopia. Method: This is part of the therapeutic efficacy studies by the Federal Ministry of Health Ethiopia, which were conducted in regionally representative sentinel sites in the country from October 2014 to January 2015. Based on the study criteria set by WHO, febrile and malaria suspected outpatients in the health center were consecutively recruited to study. A standard six-dose regimen of AL was administered over three days and followed up for measuring therapeutic responses over 28 days. Data entry and analysis was done by using the WHO designed Excel spreadsheet and SPSS version 20 for Windows. Statistical significant was considered for P-value less than 0.05. Result: Of the 91 patients enrolled, the day-28 analysis showed 83 adequate clinical and parasitological responses (ACPRs). Per protocol analysis, PCR-uncorrected & corrected cure rates of Coartem® among the study participants were 97.6% (95%CI: 93.6–99.5) and 98.8% (CI: 93.5–100%), respectively. No parasite detected on day 3 and onwards. Fever clearance was above 91% on day-3. Mean hemoglobin was significantly increased (P<0.000) from 12.39 g/dl at day 0 to 13.45 g/dl on day 28. No serious adverse drug reactions were observed among the study participants. Conclusion: This study showed high efficacy of AL in the study area, which suggests the continuation of AL as first line drug for the treatment of uncomplicated P. falciparum malaria in the study area. This study recommends further studies on drug toxicity, particularly on repeated cough and oral ulceration. [ABSTRACT FROM AUTHOR]

Strategies for successful primary treatment of HER2-positive breast cancer include use of the HER2 inhibitors trastuzumab or lapatinib in combination with standard chemotherapy. While successful, many patients develop resistance to these HER2 inhibitors indicating an unmet need. Consequently, current research efforts are geared toward understanding mechanisms of resistance and the signaling modalities that regulate these mechanisms. We have undertaken a study to examine whether signaling molecules downstream of epidermal growth factor receptor, which often act as compensatory signaling outlets to circumvent HER2 inhibition, can be co-targeted to overcome resistance. We identified JNK signaling as a potential area of intervention and now show that inhibiting JNK using the pan-JNK inhibitor, SP600125, is effective in the HER2-positive, resistant JIMT-1 xenograft mammary tumor model. We also investigate potential combination strategies to bolster the effects of JNK inhibition and find that co-targeting of JNK and the protein kinase HUNK can prohibit tumor growth of resistant HER2-positive mammary tumors in vivo. [ABSTRACT FROM AUTHOR]

The identification of a new generation of potent broadly neutralizing HIV-1 antibodies (bnAbs) has generated substantial interest in their potential use for the prevention and/or treatment of HIV-1 infection. While combinations of bnAbs targeting distinct epitopes on the viral envelope (Env) will likely be required to overcome the extraordinary diversity of HIV-1, a key outstanding question is which bnAbs, and how many, will be needed to achieve optimal clinical benefit. We assessed the neutralizing activity of 15 bnAbs targeting four distinct epitopes of Env, including the CD4-binding site (CD4bs), the V1/V2-glycan region, the V3-glycan region, and the gp41 membrane proximal external region (MPER), against a panel of 200 acute/early clade C HIV-1 Env pseudoviruses. A mathematical model was developed that predicted neutralization by a subset of experimentally evaluated bnAb combinations with high accuracy. Using this model, we performed a comprehensive and systematic comparison of the predicted neutralizing activity of over 1,600 possible double, triple, and quadruple bnAb combinations. The most promising bnAb combinations were identified based not only on breadth and potency of neutralization, but also other relevant measures, such as the extent of complete neutralization and instantaneous inhibitory potential (IIP). By this set of criteria, triple and quadruple combinations of bnAbs were identified that were significantly more effective than the best double combinations, and further improved the probability of having multiple bnAbs simultaneously active against a given virus, a requirement that may be critical for countering escape in vivo. These results provide a rationale for advancing bnAb combinations with the best in vitro predictors of success into clinical trials for both the prevention and treatment of HIV-1 infection. [ABSTRACT FROM AUTHOR]

Use of estrogen or estrogen / progestin combination was an approved regimen for menopausal hormonal therapy (MHT). However, more recent patient-centered studies revealed an increase in the incidence of breast cancer in women receiving menopausal hormone therapy with estrogen plus progestin rather than estrogen alone. Tissue selective estrogen complex (TSEC) has been proposed to eliminate the progesterone component of MHT with supporting evidences. Based on our previous studies it is evident that SPRMs have a safer profile on endometrium in preventing unopposed estrogenicity. We hypothesized that a combination of estradiol (E2) with selective progesterone receptor modulator (SPRM) to exert a safer profile on endometrium will also reduce mammary gland proliferation and could be used to prevent breast cancer when used in MHT. In order to test our hypothesis, we compared the estradiol alone or in combination with our novel SPRMs, EC312 and EC313. The compounds were effectively controlled E2 mediated cell proliferation and induced apoptosis in T47D breast cancer cells. The observed effects were found comparable that of BZD in vitro. The effects of SPRMs were confirmed by receptor binding studies as well as gene and protein expression studies. Proliferation markers were found downregulated with EC312/313 treatment in vitro and reduced E2 induced mammary gland proliferation, evidenced as reduced ductal branching and terminal end bud growth in vivo. These data supporting our hypothesis that E2+EC312/EC313 blocked the estrogen action may provide basic rationale to further test the clinical efficacy of SPRMs to prevent breast cancer incidence in postmenopausal women undergoing MHT. [ABSTRACT FROM AUTHOR]

Background: Decreased hemoglobin (Hb) level has been supposed to be a relatively rare side effect of a combination therapy against hepatitis C virus that consists of the NS5A inhibitor daclatasvir (DCV) and the NS3/4A protease inhibitor asunaprevir (ASV). Methods: The study was conducted in 75 patients with genotype 1b chronic hepatitis C virus infection who had started combination therapy with DCV and ASV at St. Marianna University School of Medicine Hospital between September 2014 and December 2014. Results: Among the patients examined, decreased Hb level by ≥1.5 g/dL from the values at treatment initiation was observed in 11 individuals. This was accompanied by decreased mean corpuscular volume, and iron and ferritin levels. Conclusions: These findings suggest that the mechanism of the phenomenon is caused by iron deficiency. The underlying mechanism and clinical impacts will need to be further examined. [ABSTRACT FROM AUTHOR]

Blockade of epidermal growth factor receptor (EGFR) activity has been a primary therapeutic target for non-small cell lung cancers (NSCLC). As patients with wild-type EGFR have demonstrated only modest benefit from EGFR tyrosine kinase inhibitors (TKIs), there is a need for additional therapeutic approaches in patients with wild-type EGFR. As a key component of downstream integrin signalling and known receptor cross-talk with EGFR, we hypothesized that targeting focal adhesion kinase (FAK) activity, which has also been shown to correlate with aggressive stage in NSCLC, would lead to enhanced activity of EGFR TKIs. As such, EGFR TKI-resistant NSCLC cells (A549, H1299, H1975) were treated with the EGFR TKI erlotinib and FAK inhibitors (PF-573,228 or PF-562,271) both as single agents and in combination. We determined cell viability, apoptosis and 3-dimensional growth in vitro and assessed tumor growth in vivo. Treatment of EGFR TKI-resistant NSCLC cells with FAK inhibitor alone effectively inhibited cell viability in all cell lines tested; however, its use in combination with the EGFR TKI erlotinib was more effective at reducing cell viability than either treatment alone when tested in both 2- and 3-dimensional assays in vitro, with enhanced benefit seen in A549 cells. This increased efficacy may be due in part to the observed inhibition of Akt phosphorylation when the drugs were used in combination, where again A549 cells demonstrated the most inhibition following treatment with the drug combination. Combining erlotinib with FAK inhibitor was also potent in vivo as evidenced by reduced tumor growth in the A549 mouse xenograft model. We further ascertained that the enhanced sensitivity was irrespective of the LKB1 mutational status. In summary, we demonstrate the effectiveness of combining erlotinib and FAK inhibitors for use in known EGFR wild-type, EGFR TKI resistant cells, with the potential that a subset of cell types, which includes A549, could be particularly sensitive to this combination treatment. As such, further evaluation of this combination therapy is warranted and could prove to be an effective therapeutic approach for patients with inherent EGFR TKI-resistant NSCLC. [ABSTRACT FROM AUTHOR]

Cancer cells are characterized by metabolic alterations, namely, depressed mitochondrial oxidation, enhanced glycolysis and pentose phosphate shunt flux to support rapid cell growth, which is called the Warburg effect. In our study we assessed the metabolic consequences of a joint treatment of MCF-7 breast cancer cells with AICAR, an inducer of AMP-activated kinase (AMPK) jointly with methotrexate (MTX), a folate-analog antimetabolite that blunts de novo nucleotide synthesis. MCF7 cells, a model of breast cancer cells, were resistant to the individual application of AICAR or MTX, however combined treatment of AICAR and MTX reduced cell proliferation. Prolonged joint application of AICAR and MTX induced AMPK and consequently enhanced mitochondrial oxidation and reduced the rate of glycolysis. These metabolic changes suggest an anti-Warburg rearrangement of metabolism that led to the block of the G1/S and the G2/M transition slowing down cell cycle. The slowdown of cell proliferation was abolished when mitotropic transcription factors, PGC-1α, PGC-1β or FOXO1 were silenced. In human breast cancers higher expression of AMPKα and FOXO1 extended survival. AICAR and MTX exerts similar additive antiproliferative effect on other breast cancer cell lines, such as SKBR and 4T1 cells, too. Our data not only underline the importance of Warburg metabolism in breast cancer cells but nominate the AICAR+MTX combination as a potential cytostatic regime blunting Warburg metabolism. Furthermore, we suggest the targeting of AMPK and FOXO1 to combat breast cancer. [ABSTRACT FROM AUTHOR]

Background: Not all new drug products are truly new. Some are the result of marginal innovation and incremental patenting of existing products, but in such a way that confers no major therapeutic improvement. This phenomenon, pejoratively known as “evergreening”, can allow manufacturers to preserve market exclusivity, but without significantly bettering the standard of care. Other studies speculate that evergreening is especially problematic for medicine/device combination products, because patents on the device component may outlast expired patents on the medicine component, and thereby keep competing, possibly less-expensive generic products off the market. Materials and Methods: We focused on four common conditions that are often treated by medicine/device product combinations: asthma and chronic obstructive pulmonary disease (COPD), diabetes, and severe allergic reactions. The patent data for a sample of such products (n = 49) for treating these conditions was extracted from the United States Food and Drug Administration’s Orange Book. Additional patent-related data (abstracts, claims, etc) were retrieved using LexisNexis TotalPatent. Comparisons were then made between each product’s device patents and medicine patents. Results: Unexpired device patents exist for 90 percent of the 49 medicine/device product combinations studied, and were the only sort of unexpired patent for 14 products. Overall, 55 percent of the 235 patents found by our study were device patents. Comparing the last-to-expire device patent to that of the last-to-expire active ingredient patent, the median additional years of patent protection afforded by device patents was 4.7 years (range: 1.3–15.2 years). Conclusion: Incremental, patentable innovation in devices to extend the overall patent protection of medicine/device product combinations is very common. Whether this constitutes “evergreening” depends on whether these incremental innovations and the years of extra patent protection they confer are proportionately matched by therapeutic improvements in the standard of care, which is highly debatable. [ABSTRACT FROM AUTHOR]

Pancreatic cancer is the leading cause of death from solid malignancies worldwide. Currently, gemcitabine is the only drug approved for treating pancreatic cancer. Developing new therapeutic drugs for this disease is, therefore, an urgent need. The C-Map project has provided a wealth of gene expression data that can be mined for repositioning drugs, a promising approach to new drug discovery. Typically, a drug is considered potentially useful for treating a disease if the drug-induced differential gene expression profile is negatively correlated with the differentially expressed genes in the target disease. However, many of the potentially useful drugs (PUDs) identified by gene expression profile correlation are likely false positives because, in C-Map, the cultured cell lines to which the drug is applied are not derived from diseased tissues. To solve this problem, we developed a combined approach for predicting candidate drugs for treating pancreatic cancer. We first identified PUDs for pancreatic cancer by using C-Map-based gene expression correlation analyses. We then applied an algorithm (Met-express) to predict key pancreatic cancer (KPC) enzymes involved in pancreatic cancer metabolism. Finally, we selected candidates from the PUDs by requiring that their targets be KPC enzymes or the substrates/products of KPC enzymes. Using this combined approach, we predicted seven candidate drugs for treating pancreatic cancer, three of which are supported by literature evidence, and three were experimentally validated to be inhibitory to pancreatic cancer celllines. [ABSTRACT FROM AUTHOR]

Background: Solitary cysticercus granuloma (SCG) is the commonest form of neurocysticercosis in the Indian subcontinent and in travelers. Several different treatment options exist for SCG. We conducted a Bayesian network meta-analysis of randomized clinical trials (RCTs) to identify the best treatment option to prevent seizure recurrence and promote lesion resolution for patients with SCG. Methods and Principal Findings: PubMed, EMBASE and the Cochrane Library databases (up to June 1, 2015) were searched for RCTs that compared any anthelmintics or corticosteroids, alone or in combination, with placebo or head to head and reported on seizure recurrence and lesion resolution in patients with SCG. A total of 14 RCTs (1277 patients) were included in the quantitative analysis focusing on four different treatment options. A Bayesian network model computing odds ratios (OR) with 95% credible intervals (CrI) and probability of being best (Pbest) was used to compare all interventions simultaneously. Albendazole and corticosteroids combination therapy was the only regimen that significantly decreased the risk of seizure recurrence compared with conservative treatment (OR 0.32, 95% CrI 0.10–0.93, Pbest 73.3%). Albendazole and corticosteroids alone or in combination were all efficacious in hastening granuloma resolution, but the combined therapy remained the best option based on probability analysis (OR 3.05, 95% CrI 1.24–7.95, Pbest 53.9%). The superiority of the combination therapy changed little in RCTs with different follow-up durations and in sensitivity analyses. The limitations of this study include high risk of bias and short follow-up duration in most studies. Conclusions: Dual therapy of albendazole and corticosteroids was the most efficacious regimen that could prevent seizure recurrence and promote lesion resolution in a follow-up period of around one year. It should be recommended for the management of SCG until more high-quality evidence is available. [ABSTRACT FROM AUTHOR]

Flux balance analysis (FBA) is an increasingly useful approach for modeling the behavior of metabolic systems. However, standard FBA modeling of genetic knockouts cannot predict drug combination synergies observed between serial metabolic targets, even though such synergies give rise to some of the most widely used antibiotic treatments. Here we extend FBA modeling to simulate responses to chemical inhibitors at varying concentrations, by diverting enzymatic flux to a waste reaction. This flux diversion yields very similar qualitative predictions to prior methods for single target activity. However, we find very different predictions for combinations, where flux diversion, which mimics the kinetics of competitive metabolic inhibitors, can explain serial target synergies between metabolic enzyme inhibitors that we confirmed in Escherichia coli cultures. FBA flux diversion opens the possibility for more accurate genome-scale predictions of drug synergies, which can be used to suggest treatments for infections and other diseases. [ABSTRACT FROM AUTHOR]

To date there are no approved antiviral drugs for the treatment of Ebola virus disease (EVD). While a number of candidate drugs have shown limited efficacy in vitro and/or in non-human primate studies, differences in experimental methodologies make it difficult to compare their therapeutic effectiveness. Using an in vitro model of Ebola Zaire replication with transcription-competent virus like particles (trVLPs), requiring only level 2 biosafety containment, we compared the activities of the type I interferons (IFNs) IFN-α and IFN-ß, a panel of viral polymerase inhibitors (lamivudine (3TC), zidovudine (AZT) tenofovir (TFV), favipiravir (FPV), the active metabolite of brincidofovir, cidofovir (CDF)), and the estrogen receptor modulator, toremifene (TOR), in inhibiting viral replication in dose-response and time course studies. We also tested 28 two- and 56 three-drug combinations against Ebola replication. IFN-α and IFN-ß inhibited viral replication 24 hours post-infection (IC50 0.038μM and 0.016μM, respectively). 3TC, AZT and TFV inhibited Ebola replication when used alone (50–62%) or in combination (87%). They exhibited lower IC50 (0.98–6.2μM) compared with FPV (36.8μM), when administered 24 hours post-infection. Unexpectedly, CDF had a narrow therapeutic window (6.25–25μM). When dosed >50μM, CDF treatment enhanced viral infection. IFN-ß exhibited strong synergy with 3TC (97.3% inhibition) or in triple combination with 3TC and AZT (95.8% inhibition). This study demonstrates that IFNs and viral polymerase inhibitors may have utility in EVD. We identified several 2 and 3 drug combinations with strong anti-Ebola activity, confirmed in studies using fully infectious ZEBOV, providing a rationale for testing combination therapies in animal models of lethal Ebola challenge. These studies open up new possibilities for novel therapeutic options, in particular combination therapies, which could prevent and treat Ebola infection and potentially reduce drug resistance. [ABSTRACT FROM AUTHOR]

Although 5-fluorouracil (5-Fu) combination chemotherapy provides a satisfactory therapeutic response in patients with gestational trophoblastic neoplasms (GTNs), it has severe side effects. The current study analyzed the therapeutic effects and side effects of tegafur plus actinomycin D (Act-D) vs. 5-Fu plus Act-D for the treatment of GTNs based on controlled historical records. A total of 427 GTN cases that received tegafur and Act-D combination chemotherapy at the Second Xiangya Hospital of XiangYa Medical School between August 2003 and July 2013 were analyzed based on historical data. A total of 393 GTN cases that received 5-Fu plus Act-D between August 1993 and July 2003 at the same hospital were also analyzed, which constituted the control group. The therapeutic effects, toxicity and side effects after chemotherapy were compared between the groups. The overall response rate was 90.63% in the tegafur+Act-D group (tegafur group) and 92.37% in the 5-Fu+Act-D group (5-Fu group); these rates were not significantly different (P > 0.05). However, the incidence rates of myelosuppression (white blood cell decline), gastrointestinal reactions (nausea, vomiting, dental ulcer, and diarrhea), skin lesions and phlebitis were lower in the tegafur group than in the 5-Fu group (P < 0.05). The results of this study may provide useful data for the clinical application of tegafur in GTN treatment. [ABSTRACT FROM AUTHOR]

The multikinase inhibitor regorafenib (BAY 73–4506) exerts both anti-angiogenic and anti-tumorigenic activity in adult solid malignancies mainly advanced colorectal cancer and gastrointestinal stromal tumors. We intended to explore preclinically the potential of regorafenib against solid pediatric malignancies alone and in combination with anticancer agents to guide the pediatric development plan. In vitro effects on cell proliferation were screened against 33 solid tumor cell lines of the Innovative Therapies for Children with Cancer (ITCC) panel covering five pediatric solid malignancies. Regorafenib inhibited cell proliferation with a mean half maximal growth inhibition of 12.5 μmol/L (range 0.7 μmol/L to 28 μmol/L). In vivo, regorafenib was evaluated alone at 10 or 30 mg/kg/d or in combination with radiation, irinotecan or the mitogen-activated protein kinase kinase (MEK) inhibitor refametinib against various tumor types, including patient-derived brain tumor models with an amplified platelet-derived growth factor receptor A (PDGFRA) gene. Regorafenib alone significantly inhibited tumor growth in all xenografts derived from nervous system and connective tissue tumors. Enhanced effects were observed when regorafenib was combined with irradiation and irinotecan against PDGFRA amplified IGRG93 glioma and IGRM57 medulloblastoma respectively, resulting in 100% tumor regressions. Antitumor activity was associated with decreased tumor vascularization, inhibition of PDGFR signaling, and induction of apoptotic cell death. Our work demonstrates that regorafenib exhibits significant antitumor activity in a wide spectrum of preclinical pediatric models through inhibition of angiogenesis and induction of apoptosis. Furthermore, radio- and chemosensitizing effects were observed with DNA damaging agents in PDGFR amplified tumors. [ABSTRACT FROM AUTHOR]

Background: Malaria still remains a major health issue in Ghana despite the introduction of Artemisinin-based combination therapy (ACT) coupled with other preventative measures such as the use of insecticide treated nets (ITNs). The global quest for eradication of malaria has heightened the interest of identifying drugs that target the sexual stage of the parasite, referred to as transmission-blocking drugs. This study aimed at assessing the efficacy and gametocydal effects of some commonly used herbal malaria products in Ghana. Methodology/Principal Findings: After identifying herbal anti-malarial products frequently purchased on the Ghanaian market, ten of them were selected and lyophilized. In vitro drug sensitivity testing of different concentrations of the herbal products was carried out on asexual and in vitro generated gametocytes of the 3D7 strain of Plasmodium falciparum. The efficacies of the products were assessed by microscopy. Cultures containing low dose of RT also produced the least number of late stage gametocytes. Two of the herbal products CM and RT inhibited the growth of late stage gametocytes by > 80% at 100 μg/ml whilst KG was the most inhibitory to early stage gametocytes at that same concentration. However at 1 μg/ml, only YF significantly inhibited the survival of late stage gametocytes although at that same concentration YF barely inhibited the survival of early stage gametocytes. Conclusions/Significance: Herbal product RT (Aloe schweinfurthii, Khaya senegalensis, Piliostigma thonningii and Cassia siamea) demonstrated properties of a highly efficacious gametocydal product. Low dose of herbal product RT exhibited the highest gametocydal activity and at 100 μg/ml, RT exhibited >80% inhibition of late stage gametocytes. However inhibition of asexual stage parasite by RT was not optimal. Improving the asexual inhibition of RT could convert RT into an ideal antimalarial herbal product. We also found that generally C. sanguinolenta containing herbal products exhibited gametocydal activity in addition to high asexual efficacy. Herbal products with high gametocydal activity can help in the fight to reduce malaria transmission. [ABSTRACT FROM AUTHOR]

Background: Cough syrups are widely used in the developing world, but safety of their use in infants and children less than two years has not been well documented. Some syrups contain multiple combinations of such drugs as promethazine, diphenhydramine and ephedrine; which are individually now contraindicated in children less than two years. Despite this, the syrups are available as over the counter drugs and may be dispensed to mothers who are unaware of the potentially hazardous effects to their infants. A descriptive cross-sectional study was used to investigate suitability of cough syrups sold within Eldoret municipality for use in children less than two years of age based on their formulations and available literature. Methods: Two semi-structured questionnaires were administered to pharmacy attendants and mothers attending sick child clinic at a referral hospital to establish whether cough syrups containing more than one active ingredient of compounds, now contraindicated in children are administered to infants, and awareness of potential serious adverse effects. Data from labeled contents of cough syrups from retail pharmacies was recorded and corroborated with information from literature to determine those deemed to contain the ingredients. The second questionnaire was administered to mothers with children less than two years to ascertain whether they had used the identified syrups. A total of 260 mothers and 55 pharmacy attendants were interviewed. Results: There was widespread use of the syrups in children, including infants, with 192 (74%) of the respondents having used identified syrups and over 90% of these on children less than 2 years including those less than three months.146 (76%) mothers had administered the syrup at double the recommended dose. Conclusion: The regulatory authorities should make concerted efforts to discourage use of cough syrups containing ingredients that pose adverse events to infants, including campaigns to educate pharmacy workers and mothers. [ABSTRACT FROM AUTHOR]

Synthetic lethality is a genetic interaction wherein two otherwise nonessential genes cause cellular inviability when knocked out simultaneously. Drugs can mimic genetic knock-out effects; therefore, our understanding of promiscuous drugs, polypharmacology-related adverse drug reactions, and multi-drug therapies, especially cancer combination therapy, may be informed by a deeper understanding of synthetic lethality. However, the colossal experimental burden in humans necessitates in silico methods to guide the identification of synthetic lethal pairs. Here, we present SINaTRA (Species-INdependent TRAnslation), a network-based methodology that discovers genome-wide synthetic lethality in translation between species. SINaTRA uses connectivity homology, defined as biological connectivity patterns that persist across species, to identify synthetic lethal pairs. Importantly, our approach does not rely on genetic homology or structural and functional similarity, and it significantly outperforms models utilizing these data. We validate SINaTRA by predicting synthetic lethality in S. pombe using S. cerevisiae data, then identify over one million putative human synthetic lethal pairs to guide experimental approaches. We highlight the translational applications of our algorithm for drug discovery by identifying clusters of genes significantly enriched for single- and multi-drug cancer therapies. [ABSTRACT FROM AUTHOR]

Background: Clostridium difficile infection (CDI) has become a global epidemiological problem for both hospitalized patients and outpatients. The most commonly used drugs to treat CDI are metronidazole and vancomycin. The aim of this study was to compare the efficacy and safety of metronidazole monotherapy with vancomycin monotherapy and combination therapy in CDI patients. Methods: A comprehensive search without publication status or other restrictions was conducted. Studies comparing metronidazole monotherapy with vancomycin monotherapy or combination therapy in patients with CDI were considered eligible. Meta-analysis was performed using the Mantel-Haenszel fixed-effects model, and odds ratios (ORs) with 95% confidence intervals (95% CIs) were calculated and reported. Results: Of the 1910 records identified, seventeen studies from thirteen articles (n = 2501 patients) were included. No statistically significant difference in the rate of clinical cure was found between metronidazole and vancomycin for mild CDI (OR = 0.67, 95% CI (0.45, 1.00), p = 0.05) or between either monotherapy and combination therapy for CDI (OR = 1.07, 95% CI (0.58, 1.96), p = 0.83); however, the rate of clinical cure was lower for metronidazole than for vancomycin for severe CDI (OR = 0.46, 95% CI (0.26, 0.80), p = 0.006). No statistically significant difference in the rate of CDI recurrence was found between metronidazole and vancomycin for mild CDI (OR = 0.99, 95% CI (0.40, 2.45), p = 0.98) or severe CDI (OR = 0.98, 95% CI (0.63, 1.53), p = 0.94) or between either monotherapy and combination therapy for CDI (OR = 0.91, 95% CI (0.66, 1.26), p = 0.56). In addition, there was no significant difference in the rate of adverse events (AEs) between metronidazole and vancomycin (OR = 1.18, 95% CI (0.80, 1.74), p = 0.41). In contrast, the rate of AEs was significantly lower for either monotherapy than for combination therapy (OR = 0.30, 95% CI (0.17, 0.51), p<0.0001). Conclusions: Metronidazole and vancomycin are equally effective for the treatment of mild CDI, but vancomycin is superior for the treatment of severe CDI. Combination therapy is not superior to monotherapy because it appears to be associated with an increase in the rate of AEs. [ABSTRACT FROM AUTHOR]