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Monoclonal antibodies (mAbs) are revolutionizing management of non-communicable diseases in high-income countries and are increasingly being advanced for a range of infectious diseases (IDs). However, access to existing mAbs is limited in low- and middle-income countries (LMICs), and investment in developing fit-for-purpose mAbs for IDs that disproportionately affect LMICs has been limited. Underlying these access barriers are systemic challenges, including a lack of commercial incentives to target LMIC markets and complexity in manufacturing and regulatory processes. Novel strategies are needed to overcome systemic access barriers for mAbs. We outline key areas where new approaches could address these barriers, based on a multistakeholder consultation in March 2023. Three disease-market archetypes are identified to guide thinking about business models tailored to different contexts. New business models are needed to incentivize development and manufacturing of ID mAbs and to ensure mAbs are optimized with a target product profile and cost of goods that enable use in diverse LMIC settings. Lessons can be applied from voluntary licensing strategies and product development partnerships that have shown success in catalysing development and affordable supply for a range of infectious diseases. Technology transfer will be key to expand LMIC research and manufacturing capacity and to enable sustainable and diversified supply. Improved market intelligence, demand aggregation mechanisms, and portfolio-based manufacturing models could be used to de-risk commercial investment and establish a sustainable manufacturing ecosystem for affordable mAbs. Novel regulatory approaches and robust technology transfer may reduce data requirements and timelines for biosimilar approvals. Trailblazer products, with coordinated "end-to-end" support from funders, can demonstrate proof of concept for pathways to accessible mAbs across a broader range of LMICs. Research funders; local, regional, global health agencies; and, private sector partners should commit to implementing innovative partnerships and end-to-end strategies that enable equitable access to mAbs for infectious diseases in LMICs.
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Public health voluntary licensing of intellectual property has successfully been applied to increase access to medicines in certain disease areas, producing health benefits and economic savings, particularly in low-income and middle-income countries. There is however limited understanding of the intricacies of the approach, the modalities by which it works in practice, its levers and the trade-offs made. Such knowledge may be critical in deciding what role licensing should have in pandemic preparedness and equitable access to health technologies more broadly. This paper examines the case for licensing, the considerations for balancing public health needs, the challenges of negotiations, and the processes for validating proposed agreements. No access mechanism is perfect, but evidence suggests that public-health licensing has an important role to play, although it remains underused. Understanding some of the realities, strengths, limitations and complexities of applying the model may help calibrate expectations and develop incentives to expand its applications.
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Negociação , Saúde Pública , Humanos , Tecnologia Biomédica , Renda , PandemiasRESUMO
INTRODUCTION: Emerging long-acting (LA) prevention and treatment medicines, technologies and regimens could be game-changing for the HIV response, helping reach the ambitious goal of halting the epidemic by 2030. To attain this goal, the rapid expansion of at-scale, sustainable, quality-assured, and affordable supplies of LA HIV prevention and treatment products through accelerated and stronger competition, involving both originator and generic companies, will be essential. To do this, global health stakeholders should take advantage of voluntary licensing of intellectual property (IP) rights, such as through the United Nations-backed, not-for-profit Medicines Patent Pool, as a proven mechanism to support broad access to existing HIV medicines across low- and middle-income countries (LMICs). DISCUSSION: While voluntary licensing may unlock the possibility for generic competition to take place ahead of patent expiry, there are additional elements-of amplified importance for more complex LA HIV medicines-that need to be taken into consideration. This paper discusses 10 enablers of voluntary licensing of IP rights as a model to rapidly expand at-scale, sustainable, quality-assured, and affordable supplies of LA HIV prevention and treatment regimens in LMICs: Identifying promising LA technology platforms and drug formulations at an early developmental stage and engaging with patent holders Consolidating a multidisciplinary network and strengthening early-stage coordination and collaboration to foster innovation Embedding public health considerations in product design and delivery Building innovative partnerships for product development and commercialization Raising awareness of and creating demand for emerging LA products Estimating the market size, ensuring sufficient competition and protecting sustainability Using technology transfer and hands-on technical support to reduce product development timelines and costs Exploring de-risking mechanisms and financial incentives to support generic manufacturers Optimizing strategies for generic product development and regulatory filings Aligning and coordinating efforts of stakeholders across the value chain. CONCLUSIONS: Rapid access to emerging LA prevention and treatment regimens and technologies can be facilitated by voluntary licensing-catalyzed and supplemented by enabling collaborative and non-duplicative efforts of various other stakeholders. This can effectively lead to improved-accelerated and cheaper-access to quality-assured medicines for populations in LMICs.
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Países em Desenvolvimento , Infecções por HIV , Humanos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Medicamentos Genéricos/uso terapêutico , Aspirações Psicológicas , Suplementos NutricionaisRESUMO
Biotherapeutics, such as recombinant proteins and monoclonal antibodies, have become mainstays of modern medicine as shown by their increasing number in the WHO Model List of Essential Medicines. However, despite frequently offering clinical advantages over standards of care, they remain largely out of reach for populations in low-income and middle-income countries (LMICs), partly because of high costs. Accordingly, the WHO Model List of Essential Medicines Expert Committee has requested that the Medicines Patent Pool explore intellectual property licensing to address this challenge. We therefore investigated how licensing could successfully improve affordability of and timely access to biotherapeutics in LMICs, by leveraging expert consultations, literature analysis, and internal technical knowledge. The key elements identified as relevant to support access to affordable biosimilars in LMICs through licensing include: prioritising potential biotherapeutic targets according to their potential for public health impact; supporting biosimilar product and clinical development (including through technology transfer to expedite regulatory approval); and facilitating biosimilars' entry and use in LMICs (by meeting procurement, supply chain, and health system requirements).
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Medicamentos Biossimilares , Medicamentos Essenciais , Humanos , Países em Desenvolvimento , Saúde Pública , Propriedade IntelectualRESUMO
Children, although at lower risk of poor outcomes from COVID-19 relative to adults, still stand to benefit from therapeutic interventions. Understanding of COVID-19 clinical presentation and prognosis in children is essential to optimize therapeutic trials design. This perspective illustrates how to collectively accelerate pediatric COVID-19 therapeutic research and development, based on the experience of the Global Accelerator for Paediatric Formulations.
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Tratamento Farmacológico da COVID-19 , Pesquisa , Convulsões/tratamento farmacológico , Criança , Formas de Dosagem , Composição de Medicamentos , Desenvolvimento de Medicamentos , Humanos , Avaliação das Necessidades , Preparações Farmacêuticas , SARS-CoV-2RESUMO
BACKGROUND: Non-exclusive voluntary licensing that is access-oriented has been suggested as an option to increase access to medicines to address the COVID-19 pandemic. To date, there has been little research on the effect of licensing, mainly focused on economic and supply chain considerations, and not on the benefits in terms of health outcomes. We aimed to study the economic and health effect of voluntary licensing for medicines for HIV and hepatitis C virus (HCV) in low-income and middle-income countries (LMICs). METHODS: A robust modelling framework was created to examine the difference between scenarios, with (factual) and without (counterfactual) a Medicines Patent Pool (MPP) licence for two medicines, dolutegravir and daclatasvir. Data were obtained from MPP licensees, as well as a large number of external sources. The primary outcomes were the cost savings and health impact between scenarios with and without MPP licences across all LMICs. Through its licences, MPP had access to the volumes and prices of licensed generic products sold in all covered countries on a quarterly basis. These data informed the volumes, prices, and uptake for the past factual scenarios and were the basis for modelling the future factual scenarios. These scenarios were then compared with a set of counterfactual scenarios in the absence of the studied licences. FINDINGS: Cumulatively, between 2017 and 2032, the model's central assumptions predicted an additional uptake of 15·494 (range 14·406-15·494) million patient-years of dolutegravir-based HIV treatments, 151 839 (34 575-312 973) deaths averted, and US$3·074 (1·837-5·617) billion saved through the MPP licence compared with the counterfactual scenario. For daclatasvir-based HCV treatments, the cumulative effect from 2015 to 2026 was predicted to be an additional uptake of 428 244 (127 584-636 270) patients treated with daclatasvir, 4070 (225-6323) deaths averted, and $107·593 (30·377-121·284) million saved with the licence compared with the counterfactual scenario. INTERPRETATION: The chain of effects linking upstream licensing to downstream outcomes can be modelled. Accordingly, credible quantitative estimates of economic and health effects arising from access-oriented voluntary licensing were obtained based on assumptions that early generic competition leads to price reductions that influence procurement decisions and enable the faster and broader uptake of recommended medicines, with beneficial economic and health effects. FUNDING: Unitaid.
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Tratamento Farmacológico da COVID-19 , Países em Desenvolvimento , Propriedade Intelectual , Licenciamento/economia , Medicamentos sob Prescrição , Saúde Pública/economia , SARS-CoV-2 , Competição Econômica , Humanos , Avaliação de Resultados em Cuidados de SaúdeRESUMO
Progress in the development and introduction of paediatric formulations for key infectious diseases is poor in low-income and middle-income countries (LMICs). Although major steps have been made in the scale-up of antiretroviral medicines in LMICs, the development and deployment of formulations for infants and children is suboptimal. Of the children living with HIV globally (most in Africa), only 43% are receiving antiretroviral therapy (ART), many with suboptimal formulations. These shortfalls pose a series of challenges to meeting global treatment targets of 1·6 million children (aged 0-14 years) on ART by the end of 2018 (95% coverage) and to ensuring that 95% of those on ART are virologically suppressed. The Global Accelerator for Paediatric Formulations (GAP-f) has been developed to accelerate research, development, regulatory filing, introduction, and uptake of prioritised paediatric antiretrovirals in age-appropriate formulations by 2020, with innovative, strategic, and sustainable financing. The GAP-f will build on existing efforts to maximise coordination and alignment of policy makers, research networks, regulatory agencies, funding organisations, and manufacturers in paediatric HIV and other paediatric diseases, including tuberculosis, viral hepatitis, and other infectious diseases. Paediatric drug development and scale-up will require special efforts to bring greater visibility and new solutions to ensure that children in LMICs have access to effective and appropriate treatment options.
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Fármacos Anti-HIV/administração & dosagem , Composição de Medicamentos , Infecções por HIV/tratamento farmacológico , Adolescente , África , Criança , Pré-Escolar , Países em Desenvolvimento , Feminino , Humanos , Lactente , Recém-Nascido , MasculinoRESUMO
INTRODUCTION: Worldwide, 71 million people are infected with hepatitis C virus (HCV), which, without treatment, can lead to liver failure or hepatocellular carcinoma. HCV co-infection increases liver- and AIDS-related morbidity and mortality among HIV-positive people, despite ART. A 12-week course of HCV direct-acting antivirals (DAAs) usually cures HCV - regardless of HIV status. However, patents and high prices have created access barriers for people living with HCV, especially people who inject drugs (PWID). Inadequate access to and coverage of harm reduction interventions feed the co-epidemics of HIV and HCV; as a result, the highest prevalence of HCV is found among PWID, who face additional obstacles to treatment (including stigma, discrimination and other structural barriers). The HIV epidemic occurred during globalization of intellectual property rights, and highlighted the relationship between patents and the high prices that prevent access to medicines. Indian generic manufacturers produced affordable generic HIV treatment, enabling global scale-up. Unlike HIV, donors have yet to step forward to fund HCV programmes, although DAAs can be mass-produced at a low and sustainable cost. Unfortunately, although voluntary licensing agreements between originators and generic manufacturers enable low-income (and some lower-middle income countries) to buy generic versions of HIV and HCV medicines, most middle-income countries with large burdens of HCV infection and HIV/HCV co-infection are excluded from these agreements. Our commentary presents tactics from the HIV experience that treatment advocates can use to expand access to DAAs. DISCUSSION: A number of practical actions can help increase access to DAAs, including new research and development (R&D) paradigms; compassionate use, named-patient and early access programmes; use of TRIPS flexibilities such as compulsory licences and patent oppositions; and parallel importation via buyers' clubs. Together, these approaches can increase access to antiviral therapy for people living with HIV and viral hepatitis in low-, middle- and high-income settings. CONCLUSIONS: The HIV example provides helpful parallels for addressing challenges to expanding access to HCV DAAs. HCV treatment access - and harm reduction - should be massively scaled-up to meet the needs of PWID, and efforts should be made to tackle stigma and discrimination, and stop criminalization of drug use and possession.
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Antivirais/uso terapêutico , Infecções por HIV/tratamento farmacológico , Acessibilidade aos Serviços de Saúde , Hepatite C/tratamento farmacológico , Renda , Fármacos Anti-HIV/economia , Fármacos Anti-HIV/uso terapêutico , Antivirais/economia , Epidemias , Infecções por HIV/epidemiologia , Redução do Dano , Hepatite C/epidemiologia , Humanos , PrevalênciaRESUMO
INTRODUCTION: Despite the coordinated efforts by several stakeholders to speed up access to HIV treatment for children, development of optimal paediatric formulations still lags 8 to 10 years behind that of adults, due mainly to lack of market incentives and technical complexities in manufacturing. The small and fragmented paediatric market also hinders launch and uptake of new formulations. Moreover, the problems affecting HIV similarly affect other disease areas where development and introduction of optimal paediatric formulations is even slower. Therefore, accelerating processes for developing and commercializing optimal paediatric drug formulations for HIV and other disease areas is urgently needed. DISCUSSION: The Global Accelerator for Paediatric Formulations (GAP-f) is an innovative collaborative model that will accelerate availability of optimized treatment options for infectious diseases, such as HIV, tuberculosis and viral hepatitis, affecting children in low- and middle-income countries (LMICs). It builds on the HIV experience and existing efforts in paediatric drug development, formalizing collaboration between normative bodies, research networks, regulatory agencies, industry, supply and procurement organizations and funding bodies. Upstream, the GAP-f will coordinate technical support to companies to design and study optimal paediatric formulations, harmonize efforts with regulators and incentivize manufacturers to conduct formulation development. Downstream, the GAP-f will reinforce coordinated procurement and communication with suppliers. The GAP-f will be implemented in a three-stage process: (1) development of a strategic framework and promotion of key regulatory efficiencies; (2) testing of feasibility and results, building on the work of existing platforms such as the Paediatric HIV Treatment Initiative (PHTI) including innovative approaches to incentivize generic development and (3) launch as a fully functioning structure. CONCLUSIONS: GAP-f is a key partnership example enhancing North-South and international cooperation on and access to science and technology and capacity building, responding to Sustainable Development Goal (SDG) 17.6 (technology) and 17.9. (capacity-building). By promoting access to the most needed paediatric formulations for HIV and high-burden infectious diseases in low-and middle-income countries, GAP-f will support achievement of SDG 3.2 (infant mortality), 3.3 (end of AIDS and combat other communicable diseases) and 3.8 (access to essential medicines), and be an essential component of meeting the global Start Free, Stay Free, AIDS Free super-fast-track targets.
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Fármacos Anti-HIV/economia , Países em Desenvolvimento/economia , Composição de Medicamentos/economia , Infecções por HIV/tratamento farmacológico , Pediatria/economia , Adulto , Fármacos Anti-HIV/química , Fármacos Anti-HIV/uso terapêutico , Criança , Desenvolvimento de Medicamentos/economia , Medicamentos Genéricos/economia , Infecções por HIV/economia , Humanos , Lactente , Cooperação Internacional , PobrezaRESUMO
In vitro diagnostic devices (IVDs) help clinicians determine specific conditions, monitor therapeutic efficacy, and prevent drug resistance development. While stringent regulatory authorities (SRAs) regulate IVDs in most high-income countries, regulatory authorities in many low- and middle-income countries (LMICs) are nonexistent or do not enforce rigorous standards. In 2010, the World Health Organization established its Prequalification of In Vitro Diagnostics (PQDx) program to ensure "access to safe, appropriate and affordable" IVDs, especially in LMICs with little or no domestic regulatory frameworks, thereby reaching underserved populations. However, challenges in PQDx policies and procedures include an overloaded pipeline, timelines not publicly available, confusion about which products PQDx focuses on, perceived burden for documenting changes to prequalified products, overlap with SRA approvals, and uncertainty around long-term financing. PQDx can maximize its impact by considering the perspective of IVD manufacturers; similarly, IVD manufacturers should exercise adequate quality control over their submissions and associated processes.
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Aprovação de Teste para Diagnóstico/normas , Testes Diagnósticos de Rotina/métodos , Organização Mundial da Saúde , Países em Desenvolvimento , Guias como Assunto , HumanosRESUMO
INTRODUCTION: Globally, there is a considerable burden of HCV and HIV infections among people who inject drugs (PWID) and transmission of both infections continues. Needle and syringe programme (NSP) and opioid substitution therapy (OST) coverage remains low, despite evidence demonstrating their prevention benefit. Direct-acting antiviral therapies (DAA) with HCV cure >95% among PWID provide an opportunity to reverse rising trends in HCV-related morbidity and mortality and reduce incidence. However, HCV testing, linkage to care, and treatment remain low due to health system, provider, societal, and patient barriers. Between 2015 and 2030, WHO targets include reducing new HCV infections by 80% and HCV deaths by 65%, and increasing HCV diagnoses from <5% to 90% and number of eligible persons receiving HCV treatment from <1% to 80%. This commentary discusses why PWID should be considered as a priority population in these efforts, reasons why this goal could be attainable among PWID, challenges that need to be overcome, and key recommendations for action. DISCUSSION: Challenges to HCV elimination as a global health concern among PWID include poor global coverage of harm reduction services, restrictive drug policies and criminalization of drug use, poor access to health services, low HCV testing, linkage to care and treatment, restrictions for accessing DAA therapy, and the lack of national strategies and government investment to support WHO elimination goals. Key recommendations for action include reforming drug policies (decriminalization of drug use and/or possession, or providing alternatives to imprisonment for PWID; decriminalization of the use and provision of sterile needles-syringes; and legalization of OST for people who are opioid dependent), scaling up and improving funding for harm reduction services, making health services accessible for PWID, supporting community empowerment and community-based programmes, improving access to affordable diagnostics and medicines, and eliminating stigma, discrimination, and violence against PWID. CONCLUSIONS: The ambitious targets for HCV elimination set by WHO are achievable in many countries, but will require researchers, healthcare providers, policy makers, affected communities, advocates, the pharmaceutical and diagnostics industries, and governments around the world to work together to make this happen.
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Erradicação de Doenças , Hepatite C/prevenção & controle , Abuso de Substâncias por Via Intravenosa/complicações , Programas Governamentais , Redução do Dano , Hepatite C/epidemiologia , Hepatite C/etiologia , Humanos , Incidência , Tratamento de Substituição de Opiáceos , Saúde Pública , Abuso de Substâncias por Via Intravenosa/tratamento farmacológicoRESUMO
The International AIDS Society convened the 3rd International HIV/Viral Hepatitis Co-Infection Meeting on 17 July 2016 as part of the pre-conference program preceding the 21st International AIDS Conference held in Durban, South Africa. The meeting brought together a diversity of scientific, technical and community interests to discuss opportunities and challenges for increased prevention, diagnosis and treatment of viral hepatitis in people living with HIV, particularly in low- and middle-income settings. The objectives of the meeting were:i.To review the latest therapeutic developments in viral hepatitis;ii.To identify challenges such as high cost of medications for hepatitis C virus (HCV) and risk of developing viral resistance, and successes, such as the provision of HCV treatment in community-based settings, movements to reduce drug costs and increasing access, in relation to scaling up diagnosis, screening, antiviral treatment and prevention of viral hepatitis;iii.To advance the agenda for elimination of viral hepatitis as a public health problem. Discussions centred around the six key interventions outlined by the World Health Organization Global Health Sector Strategy on Viral Hepatitis 2016-2021: hepatitis B virus (HBV) vaccination (including birth dose); safe injection practices plus safe blood; harm reduction among people who inject drugs; safer sex practices; hepatitis B treatment; and hepatitis C cure. This article summarizes the main issues and findings discussed during the pre-conference meeting. One of the recommendations from the meeting delegates is universal implementation of birth dose vaccination for HBV without further delay to prevent mother-to-child transmission of infection. There is also the need to implement screening and treatment of hepatitis among pregnant women. A call was made for concerted efforts to be put together by all stakeholders towards addressing some of the structural barriers, including criminalization of drug use, discrimination and stigma that people living with viral hepatitis face. Finally, the need for greater advocacy was highlighted to enable access to therapy of viral hepatitis at lower cost than currently prevails. Implementation of these resolutions will help in achieving the target of eliminating viral hepatitis as a public health threat.
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Optimization of pyridine-based noncatalytic site integrase inhibitors (NCINIs) based on compound 2 has led to the discovery of molecules capable of inhibiting virus harboring N124 variants of HIV integrase (IN) while maintaining minimal contribution of enterohepatic recirculation to clearance in rat. Structure-activity relationships at the C6 position established chemical space where the extent of enterohepatic recirculation in the rat is minimized. Desymmetrization of the C4 substituent allowed for potency optimization against virus having the N124 variant of integrase. Combination of these lessons led to the discovery of compound 20, having balanced serum-shifted antiviral potency and minimized excretion in to the biliary tract in rat, potentially representing a clinically viable starting point for a new treatment option for individuals infected with HIV.
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A high-throughput screen based on a viral replication assay was used to identify inhibitors of the human cytomegalovirus. Using this approach, hit compound 1 was identified as a 4 µM inhibitor of HCMV that was specific and selective over other herpes viruses. Time of addition studies indicated compound 1 exerted its antiviral effect early in the viral life cycle. Mechanism of action studies also revealed that this series inhibited infection of MRC-5 and ARPE19 cells by free virus and via direct cell-to-cell spread from infected to uninfected cells. Preliminary structure-activity relationships demonstrated that the potency of compound 1 could be improved to a low nanomolar level, but metabolic stability was a key optimization parameter for this series. A strategy focused on minimizing metabolic hydrolysis of the N1-amide led to an alternative scaffold in this series with improved metabolic stability and good pharmacokinetic parameters in rat.
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R4.0, a synthetic CCL5/RANTES-derived peptide, exerts potent anti-HIV-1 activity via its nonactivating interaction with CCR5, the major HIV-1 coreceptor. CCR5 chronic activation may promote undesirable inflammatory effects and enhance viral infection; thus, receptor antagonism is a necessary requisite. HIV-1 gp120, CCL5, and maraviroc dock on CCR5 by sharing two receptor sites: the N terminus and the second extracellular loop. In combination studies, R4.0, CCL5, and maraviroc exhibited concomitant interactions with CCR5 and promoted synergic inhibition of HIV-1 in acute-infection assays. Furthermore, various degrees of additive/synergic HIV-1 inhibition were observed when R4.0 was tested in combination with drugs and lead compounds directed toward different viral targets (gp120, gp41, reverse transcriptase, and protease). In combination with tenofovir, R4.0 provides cross-clade synergic inhibition of primary HIV-1 isolates. Remarkably, an in vitro-generated maraviroc-resistant R5 HIV-1 strain was inhibited by R4.0 comparably to the wild-type strain, suggesting the presence of viral resistance barriers similar to those reported for CCL5. Overall, R4.0 appears to be a promising lead peptide with potential for combination in anti-HIV-1 therapy and in microbicide development to prevent sexual HIV-1 transmission.
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Fármacos Anti-HIV/farmacologia , Peptídeos/farmacologia , Receptores CCR5/química , Fármacos Anti-HIV/química , Microscopia de Fluorescência , Modelos Biológicos , Peptídeos/químicaRESUMO
An assay recapitulating the 3' processing activity of HIV-1 integrase (IN) was used to screen the Boehringer Ingelheim compound collection. Hit-to-lead and lead optimization beginning with compound 1 established the importance of the C3 and C4 substituent to antiviral potency against viruses with different aa124/aa125 variants of IN. The importance of the C7 position on the serum shifted potency was established. Introduction of a quinoline substituent at the C4 position provided a balance of potency and metabolic stability. Combination of these findings ultimately led to the discovery of compound 26 (BI 224436), the first NCINI to advance into a phase Ia clinical trial.
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A scaffold replacement approach was used to identifying the pyridine series of noncatalytic site integrase inhibitors. These molecules bind with higher affinity to a tetrameric form compared to a dimeric form of integrase. Optimization of the C6 and C4 positions revealed that viruses harboring T124 or A124 amino acid substitutions are highly susceptible to these inhibitors, but viruses having the N124 amino acid substitution are about 100-fold less susceptible. Compound 20 had EC50 values <10 nM against viruses having T124 or A124 substitutions in IN and >800 nM in viruses having N124 substitions. Compound 20 had an excellent in vitro ADME profile and demonstrated reduced contribution of biliary excretion to in vivo clearance compared to BI 224436, the lead compound from the quinoline series of NCINIs.
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UNLABELLED: Nuclear magnetic resonance (NMR) is a powerful tool for observing the motion of biomolecules at the atomic level. One technique, the analysis of relaxation dispersion phenomenon, is highly suited for studying the kinetics and thermodynamics of biological processes. Built on top of the relax computational environment for NMR dynamics is a new dispersion analysis designed to be comprehensive, accurate and easy-to-use. The software supports more models, both numeric and analytic, than current solutions. An automated protocol, available for scripting and driving the graphical user interface (GUI), is designed to simplify the analysis of dispersion data for NMR spectroscopists. Decreases in optimization time are granted by parallelization for running on computer clusters and by skipping an initial grid search by using parameters from one solution as the starting point for another -using analytic model results for the numeric models, taking advantage of model nesting, and using averaged non-clustered results for the clustered analysis. AVAILABILITY AND IMPLEMENTATION: The software relax is written in Python with C modules and is released under the GPLv3+ license. Source code and precompiled binaries for all major operating systems are available from http://www.nmr-relax.com. CONTACT: edward@nmr-relax.com.