The Application of Prodrugs as a Tool to Enhance the Properties of Nucleoside Reverse Transcriptase Inhibitors.

Antiretroviral Therapy (ART) is an effective treatment for human immunodeficiency virus (HIV) which has transformed the highly lethal disease, acquired immunodeficiency syndrome (AIDS), into a chronic and manageable condition. However, better methods need to be developed for enhancing patient access and adherence to therapy and for improving treatment in the long term to reduce adverse effects. From the perspective of drug discovery, one promising strategy is the development of anti-HIV prodrugs. This approach aims to enhance the efficacy and safety of treatment, promoting the development of more appropriate and convenient systems for patients. In this review, we discussed the use of the prodrug approach for HIV antiviral agents and emphasized nucleoside reverse transcriptase inhibitors. We comprehensively described various strategies that are used to enhance factors such as water solubility, bioavailability, pharmacokinetic parameters, permeability across biological membranes, chemical stability, drug delivery to specific sites/organs, and tolerability. These strategies might help researchers conduct better studies in this field. We also reported successful examples from the primary therapeutic classes while discussing the advantages and limitations. In this review, we highlighted the key trends in the application of the prodrug approach for treating HIV/AIDS.

Efficacy of Three Antiretroviral Regimens Initiated during Pregnancy: Clinical Experience in Rio de Janeiro.

Few studies have compared the clinical efficacy and adverse events of combined antiretroviral therapy (cART) regimens in pregnant women seeking obstetrical care. The objective of this study was to compare the efficacy (virus load response), adverse events, and obstetrical and neonatal outcomes of three different regimens of cART in HIV-infected pregnant women initiating treatment in Rio de Janeiro, Brazil. This was a retrospective cohort study of cART-naive pregnant women who initiated either ritonavir-boosted protease inhibitors (atazanavir or lopinavir), efavirenz, or raltegravir plus a backbone regimen. From 2014 to 2018, 390 pregnant women were followed over time. At baseline, the median viral load (VL) for HIV was 4.1 log copies/ml. Among participants who received cART for 2 to 7 weeks, the VL decline was greater for raltegravir (2.24 log copies/ml) than for efavirenz or protease inhibitors (P < 0.001). Virologic suppression was achieved in 87% of women on raltegravir near delivery versus 73% on efavirenz and 70% on protease inhibitors (P = 0.011). Patients on raltegravir achieved virologic suppression faster than those on other regimens (P = 0.019). Overall, the HIV perinatal infection rate was 1.5%. This clinical study compared three potent and well-tolerated cART regimens and demonstrated that a higher proportion of participants on raltegravir achieved an undetectable HIV VL near delivery (P = 0.011) compared to the other arms. These findings suggest that raltegravir-containing regimens are optimal regimens for women with HIV initiating treatment late in pregnancy.

Antiretroviral Therapies for Human Immunodeficiency Virus and Liver Disease: Challenges and opportunities.

The post antiretroviral therapy (ART) era for human immunodeficiency virus (HIV) infection resulted in a dramatically increased proportion of deaths attributed to liver-related causes in patients with HIV treated with ART. Additionally, as patients become older as a result of effective ART, liver-related conditions and application of safe therapies are now major concerns in the setting of HIV infection.

Challenges and approaches in the discovery of human immunodeficiency virus type-1 non-nucleoside reverse transcriptase inhibitors.

The type I human immunodeficiency virus (HIV-1) pandemic affecting over 37 million people worldwide continues, with 1.8 million people newly infected each year. Highly active antiretroviral therapy is efficient at reducing viral load and nearly one-half of the infected population is on treatment. One of the most successful approaches for the treatment of HIV infections is the use of inhibitors for human immunodeficiency virus type-1 reverse transcriptase (HIV-1 RT). At present, there are six nonnucleoside reverse transcriptase inhibitors (NNRTIs) approved for clinical use: nevirapine (NVP), delavirdine (DLV), efavirenz (EFV), etravirine (ETV), rilpivirine (RPV), and elsulfavirine. In this review, we will cover the development of different classes of NNRTIs over the last two decades. We will give an overview of traditional medicinal chemistry strategies for structural modification as bioisosterism principles, scaffold hopping, substitute decoration, and molecular hybridization. Furthermore, computer-aid design as virtual screening, de novo design and free-energy perturbation will be described in details.

Antiangiogenic VEGF165b expression in human breast MCF-7 and MCF-10A cells exposed to reverse transcriptase and protease inhibitors / Expresión de VEGF165b antiangiogénico en células MCF-7 y MCF-10A de mama humana expuesto a inhibidores de la transcriptasa inversa y la proteasa

The combined antiretroviral therapy (cART), a multidrug combination regimen, usually consisting Nucleoside Reverse Transcriptase Inhibitors, non- Nucleoside Reverse Transcriptase Inhibitors and Protease Inhibitors has altered the morbidity pattern affecting HIV-infected individuals to include non-AIDS-defining malignancies (nADMs). The speculation is rife; does cART induce or promote the progression of nADMs such as breast cancer? This study was therefore designed to investigate of the effects of some antiretroviral drugs (at clinically relevant concentrations) on the expression of anti-angiogenic gene; VEGF165b in two human breast cell lines; MCF-7 and MCF-10A by Real Time qPCR and immuno-fluorescence. All of the antiretroviral drugs and combinations tested produced patterns of slight up or downregulation of VEGF165b mRNA expression but the alterations did not attain statistical significance. They also did not alter VEGF165bprotein localisation in both cell lines. The findings reported here suggest that antiretroviral drugs probably do not influence the angiogenic pathway in the development of breast cancer in patients under the combined antiretroviral regimen.

El tratamiento antirretroviral combinado (TARc), un régimen de combinación de múltiples fármacos, consistiendo generalmente en inhibidores nucleósidos de la transcriptasa reversa, inhibidores no-nucleósidos de la transcriptasa reversa e inhibodres de proteasa que alteran el patrón de mortalidad que afecta a infectados por el VIH incluyendo neoplasias definidas como no HIV (nADMs). La especulación es moneda corriente; TARc induce o promueve la progresión de nADMs como cáncer de mama? Por lo tanto, este estudio se diseñó para investigar los efectos de algunos de los fármacos antirretrovirales (en concentraciones clínicamente relevantes) sobre la expresión del gen anti-angiogénico; VEGF165b en dos líneas celulares de mama humana; MCF-7 y MCF-10A por PCR tiempo real e inmunofluorescencia. Todos los fármacos antirretrovirales y las combinaciones probadas pueden regular en forma ligera hacia arriba o hacia abajo la expresión de ARNm producidos por VEGF165b pero las alteraciones no fueron estadísticamente significativos. Además, no se alteran los niveles de proteína VEGF165b, para la localización en ambas líneas celulares. Los resultados aquí presentados sugieren que los medicamentos antirretrovirales probablemente no influyen en la vía angiogénica en el desarrollo del cáncer de mama en pacientes bajo el régimen antirretroviral combinado.

Pharmacogenetic considerations in the treatment of HIV.

After the introduction of highly active antiretroviral therapy in the 1990s, the perception of the diagnosis of HIV infection gradually shifted from a 'death sentence' to a chronic disease requiring long-term treatment. The host genetic variability has been shown to play a relevant role in both antiretroviral drugs bioavailability and adverse effects susceptibility. Knowledge about pharmacogenetics role in HIV infection treatment has largely increased over the last years, and is reviewed in the present report, as well as future perspectives for the inclusion of pharmacogenetics information in the directing of HIV infection treatment.

Computational drug design strategies applied to the modelling of human immunodeficiency virus-1 reverse transcriptase inhibitors

Reverse transcriptase (RT) is a multifunctional enzyme in the human immunodeficiency virus (HIV)-1 life cycle and represents a primary target for drug discovery efforts against HIV-1 infection. Two classes of RT inhibitors, the nucleoside RT inhibitors (NRTIs) and the nonnucleoside transcriptase inhibitors are prominently used in the highly active antiretroviral therapy in combination with other anti-HIV drugs. However, the rapid emergence of drug-resistant viral strains has limited the successful rate of the anti-HIV agents. Computational methods are a significant part of the drug design process and indispensable to study drug resistance. In this review, recent advances in computer-aided drug design for the rational design of new compounds against HIV-1 RT using methods such as molecular docking, molecular dynamics, free energy calculations, quantitative structure-activity relationships, pharmacophore modelling and absorption, distribution, metabolism, excretion and toxicity prediction are discussed. Successful applications of these methodologies are also highlighted.

Didanosine-loaded chitosan microspheres optimized by surface-response methodology: a modified "Maximum Likelihood Classification" approach formulation for reverse transcriptase inhibitors.

Didanosine-loaded chitosan microspheres were developed applying a surface-response methodology and using a modified Maximum Likelihood Classification. The operational conditions were optimized with the aim of maintaining the active form of didanosine (ddI), which is sensitive to acid pH, and to develop a modified and mucoadhesive formulation. The loading of the drug within the chitosan microspheres was carried out by ionotropic gelation technique with sodium tripolyphosphate (TPP) as cross-linking agent and magnesium hydroxide (Mg(OH)2) to assure the stability of ddI. The optimization conditions were set using a surface-response methodology and applying the "Maximum Likelihood Classification", where the initial chitosan concentration, TPP and ddI concentration were set as the independent variables. The maximum ddI-loaded in microspheres (i.e. 1433 mg of ddI/g chitosan), was obtained with 2% (w/v) chitosan and 10% TPP. The microspheres depicted an average diameter of 11.42 µm and ddI was gradually released during 2 h in simulated enteric fluid.

Administração de tenofovir em ratas Wistar durante a gestação: efeitos na prole / Administration of tenofovir during pregnancy in Wistar rats: effects on the offspring

Introdução: Tenofovir disoproxil fumarate (TDF) é um inibidor da transcriptase reversa análogo nucleotídeo que tem sido usado por gestantes para o tratamento da infecção pelo vírus da imunodeficiência humana (HIV), bem como para a prevenção da transmissão vertical do vírus. Até o momento, não há estudos experimentais ou em humanos sobre a incidência de alterações renais nos fetos expostos a esquemas contendo TDF. Objetivo: Verificar a ocorrência de alterações renais e sistêmicas fetais causadas pelo uso do TDF durante a gestação. Metodologia: Ratos Wistar fêmeas receberam dieta padrão com ou sem adição de TDF (100mg/Kg de dieta) desde uma semana antes do cruzamento até o parto. A prole proveniente do grupo TDF foi colocada com uma mãe adotiva não tratada durante o período de amamentação e foi comparada com a prole de ratas que receberam dieta padrão durante a gestação (grupo controle). Controle e TDF foram acompanhados até três (n=9 para cada grupo) e seis (n=12 e n=10, respectivamente) meses de idade. Foram avaliados: peso corporal (PC) e pressão arterial sistólica (PAS) mensais, contagem de glomérulos, função renal (através do clearance de inulina), parâmetros bioquímicos (proteinúria, colesterol total, sódio e potássio séricos e urinários), e expressão proteica do tecido renal para componentes do sistema renina angiotensina aldosterona (SRAA) e para transportadores de sódio. Resultados: A prole TDF apresentou menor PC ao nascimento em comparação com o controle. Após o 3º mês, o grupo TDF demonstrou um crescimento compensatório, atingindo o sexto mês com maior PC. O peso renal foi menor no grupo TDF, porém, não houve diferença do número de néfrons entre os grupos. O grupo TDF apresentou alterações estruturais glomerulares. Observou-se também um aumento progressivo da PAS após o segundo mês de idade no grupo TDF. Não houve diferença estatística na função renal entre os grupos. Os níveis plasmáticos de aldosterona foram mais elevados...

Introduction: Tenofovir disoproxil fumarato (TDF) is a nucleotide reverse transcriptase inhibitor that has been used in pregnants for treatment of maternal HIV infection and for prevention of vertical transmission. Currently, there are no published studies providing data regarding the occurrence of renal abnormalities in fetuses exposed to TDF-containing regimens. Objective: To evaluate the occurrence of systemic and renal abnormalities in offspring of Wistar rats exposed to TDF during pregnancy. Methods: Female Wistar rats received a standard diet, with or without addition of TDF (100 mg/Kg diet), one week before mating and during pregnancy. Offspring from the TDF group were placed with an untreated foster mother during breastfeeding and compared with offspring from rats maintained on a standard diet during mating and pregnancy (control). Control and TDF were followed up at three and six months of age. Analyzed data: monthly body weight and systolic blood pressure (SBP), glomerular counting, renal function, biochemical parameters, and renal tissue immunoblotting for renin angiotensin aldosterone system (RAAS) and renal sodium transporters. Results: TDF offspring showed lower birth weight compared with the control group. After the third month, growth among the TDF group experienced a rapid catch-up. SBP increased progressively after the second month of age in the TDF group. The nephron number did not differ between groups. The TDF group showed glomerular structural changes. There was no significant difference in renal function between the groups studied. Plasma aldosterone was higher in the TDF group, associated with a significant increase in renal expression of RAAS. The TDF rats showed upregulation of renal sodium transporters and consequently lower urinary sodium excretion. Conclusions: This is the first demonstration using an experimental model that maternal exposure to TDF during gestation results in over activation of RAAS, upregulation of renal...

Nuevos y viejos anti-retrovirales en pediatría: Nuevas dosis, presentaciones y asociaciones / New and “old” antiretroviral drugs in Pediatrics: New doses, formulations and associations

De los 25 anti-retrovirales disponibles en el mercado, sólo 16 están autorizados en la edad pediátrica. Los antiretrovirales, pertenecientes a las tres primeras familias, usados desde hace dos décadas, continúan vigentes y son parte importante de la terapia anti-retroviral en niños naïve. Se describen las dosis, presentaciones y asociaciones actuales de estos fármacos en la edad pediátrica y además se comentan las nuevas co-formulaciones que permitirán disminuir el número de dosis, mejorar la tolerancia y por lo tanto conseguir mejor adherencia de los pacientes pediátricos.

Of the 25 antiretroviral drugs available in the market, only 16 are allowed for prescription in the pediatric patients. The antiretroviral, pertaining to the first three families, used for two decades, remain valid and are important components of antiretroviral therapy in naive children. We describe doses, presentations and current associations for these drugs in children, and also discuss new co-formulations that will reduce the number of doses, improve tolerance and therefore achieve better adherence of pediatric patients.