Marcadores lipídicos en los pacientes con VIH/sida en tratamiento con inhibidores de la proteasa

Introducción: Las enfermedades cardiovasculares constituyen la principal causa de morbimortalidad a escala mundial. Otra enfermedad con impacto significativo en los sistemas de salud pública es el VIH/sida. Los pacientes infectados con el virus de la inmunodeficiencia humana, tienen mayor riesgo de desarrollar enfermedades cardiovasculares. Posterior al tratamiento antirretroviral ha disminuido la incidencia de enfermedades oportunistas asociadas al VIH/sida, y se ha elevado la incidencia de enfermedades asociadas al envejecimiento, como la enfermedad cardiovascular. El uso de antirretrovirales inhibidores de la proteasa se asocia a hiperlipidemia y, por consiguiente, al aumento de complicaciones cardiovasculares. Objetivo: Determinar los marcadores lipídicos en pacientes con VIH/sida en tratamiento con inhibidores de la proteasa. Materiales y métodos: Se realizó un estudio observacional, analítico, transversal en los pacientes con VIH/sida de la provincia de Matanzas, durante el período comprendido entre marzo y agosto de 2020, en el Laboratorio Clínico del Hospital Universitario Clínico Quirúrgico Comandante Faustino Pérez Hernández. Resultados: Se evaluaron los marcadores lipídicos como factor de riesgo cardiovascular asociado al tratamiento antirretroviral, siendo los triglicéridos el de mayor incidencia. Conclusiones: Se identificaron los marcadores lipídicos como factores de riesgo cardiovascular, en este caso la hipertrigliceridemia.

Introduction: Cardiovascular diseases are the main risk of morbidity and mortality worldwide. Another disease with significant impact on public health systems is HIV/AIDS. Patients infected with the human immunodeficiency virus have a higher risk of developing cardiovascular diseases. After antiretroviral treatment, the incidence of opportunistic diseases associated with HIV/AIDS has decreased and the incidence of diseases associated with aging such as cardiovascular disease has increased. The use of protease inhibitor antiretroviral drugs is associated with hyperlipidemia and a consequent increase in cardiovascular complications. Objective: To determine lipid markers in patients with HIV/AIDS undergoing treatment with protease inhibitors. Materials and method: An observational, analytical, cross-sectional study was carried out in patients with HIV/AIDS from the province of Matanzas during the period from March to August 2020, in the Clinical Laboratory of the Provincial Teaching Clinical Surgical Hospital Faustino Pérez Hernandez. Results: Lipid markers were evaluated as cardiovascular risk factor associated with antiretroviral treatment, with triglycerides being the one of highest incidence. Conclusions: Lipid markers were identified as cardiovascular risk factors; in this case hypertriglyceridemia.

Resistencia genotípica del HIV a los antirretrovirales en niños de Argentina entre 2006 y 2021 / HIV genotypic drug resistance to antiretrovirals in children in Argentina between 2006 and 2021

Introducción: La resistencia del HIV a los antirretrovirales (ARVs) es una de las principales causas de fallo terapéutico en niños, niñas y adolescentes que conviven con el virus. Desde el año 2006, el Laboratorio de Biología Celular y Retrovirus del Hospital Garrahan realiza el estudio genotípico de resistencia (ER) del HIV-1 a los ARVs a fin de identificar mutaciones que disminuyen la susceptibilidad del virus a los fármacos que componen el tratamiento ARV. Objetivos: El objetivo del trabajo fue estudiar el tipo y frecuencia de resistencia del HIV a los ARVs, a través de un análisis de 371 ER realizados entre los años 2006 y 2021 en niños, niñas y adolescentes con HIV-1 adquirido por transmisión vertical y con solicitud médica de ER por presentar fallo terapéutico. Resultados: Entre los años 2006 y 2013 la proporción de casos con resistencia a al menos una clase de fármaco ARV fue mayor al 90%, sugiriendo una asociación directa entre el fallo virológico y la disminución en la susceptibilidad del HIV-1 a uno o más componentes del TARV. A partir del año 2012, se observa una disminución progresiva del nivel de resistencia de HIV-1, llegando al 50% en 2021 (p<0.0001). La frecuencia de mutaciones de resistencia fue diferente para cada una de las clases de ARVs. Mientras que la resistencia a INNTR no sufrió cambios significativos a lo largo del período de estudio, oscilando entre 27% y 75%. La proporción de mutaciones a IPs en pacientes con fallo virológico disminuyó de 87% en 2006 a 17% en 2021 y para los INTR, disminuyó de 79% en 2006 a 45% en 2021. Conclusión: El nivel de resistencia a los ARVs ha disminuido de manera sustancial a lo largo de los últimos 16 años, probablemente por el uso de nuevos fármacos ARV con alta potencia que posibilitaron la intensificación de los tratamientos ARV y la implementación de criterios de fallo terapéutico más estrictos tanto a nivel clínico como virológico (AU)

Introduction: HIV resistance to antiretroviral (ARV) drugs is one of the main causes of therapeutic failure in children and adolescents living with the virus. Since 2006, the Cell Biology and Retrovirus Laboratory of the Garrahan Hospital has been performing the genotypic study of HIV-1 resistance to ARV drugs in order to identify mutations that reduce the susceptibility of the virus to the drugs that constitute ARV treatment. Objectives: The aim of this study was to assess the type and frequency of HIV resistance to ARV drugs through an analysis of 371 genotype studies performed between 2006 and 2021 in children and adolescents with HIV-1 acquired through motherto-child transmission and with medical request for genotype study due to therapeutic failure. Results: Between 2006 and 2013, the proportion of cases with resistance to at least one ARV drug class was greater than 90%, suggesting a direct association between virologic failure and decreased susceptibility of HIV-1 to one or more components of ART. From 2012 onwards, a progressive decrease in the level of HIV-1 resistance was observed, reaching 50% in 2021 (p<0.0001). The frequency of resistant mutations was different for each of the ARV classes, while resistance to non-nucleoside reverse transcriptase inhibitors (NNRTIs) did not change significantly over the study period, ranging from 27% to 75%. The proportion of drug-resistant mutations to protease inhibitors (PI) in patients with virologic failure decreased from 87% in 2006 to 17% in 2021 and for NNRTIs from 79% in 2006 to 45% in 2021. Conclusion: The level of resistance to ARV drugs has decreased substantially over the last 16 years, probably due to the use of new ARV drugs with high potency that allowed the intensification of ARV treatments and the implementation of stricter criteria for therapeutic failure both clinically and virologically (AU)

Adherence to antiretroviral therapy among women living with HIV/AIDS in the interior of the Brazilian state of Pará: cross-sectional study

ABSTRACT BACKGROUND: High prevalence of human immunodeficiency virus (HIV) infection and occurrence of drug-resistant strains have been recorded in northern Brazil. Abandonment of treatment and insufficient and inadequate adherence to antiretroviral therapy (ART) among people living with HIV/AIDS (PLWHA) have been recorded in the metropolitan area of Belém, the capital of the state of Pará. OBJECTIVES: To identify the sociodemographic profile and level of adherence to ART among women seen at a referral unit in the interior of Pará, northern Brazil. DESIGN AND SETTING: Cross-sectional study at a referral unit for care for PLWHA. METHODS: We included 86 women living with HIV/AIDS (WLWHA) in the Rio Caeté integrated region, northeastern Pará. Social, demographic and behavioral information, as well as the ART level, were obtained using forms that have been described in the scientific literature. Logistic regression models were used to assess associations of variables with ART. RESULTS: Most WLWHA were single (52.4%), young (47.7%) and heterosexual (97.7%), had low levels of education (63.0%), were unemployed (69.8%), had one sexual partner (75.7%), used condoms (46.7%) and were not using either licit drugs (68.7%) or illicit drugs (89.6%). Their adherence level was classified as insufficient , and only their viral load showed an association with ART. CONCLUSIONS: The participants' low level of education and poor socioeconomic conditions may have been interfering with their adherence to ART. Such influences can be minimized through multiprofessional interventions that take the individuality of women served by the healthcare service into consideration.

Sarcoma de Kaposi oral en paciente seropositivo, fase sintomática avanzada. Presentación de caso / Oral Kaposi Sarcoma, advanced symptomatic phase, in a seropositive patient. Case presentation

RESUMEN Se presentó el caso clínico de un paciente seropositivo, en fase sintomática avanzada. Fue atendido en el Servicio de Medicina Interna del Hospital Clínico Quirúrgico Docente "León Cuervo Rubio", de la ciudad de Pinar del Río, por presentar disnea, astenia, anorexia y pérdida de peso. Al examen oral se constató lesión tumoral de la lengua que dificultaba la masticación y deglución. La biopsia mostró sarcoma de Kaposi asociado al VIH/sida. La evolución tórpida y el estadio tan avanzado de la enfermedad, propiciaron el deceso del paciente (AU).

ABSTRACT The authors presented the clinical case of a seropositive patient, in advanced symptomatic phase. The patient attended the Internal Medicine Service of the Teaching Clinical Surgical Hospital Leon Cuervo Rubio of Pinar del Rio, presenting dyspnea, asthenia, anorexia and weight loss. On the oral examination, a tumor lesion was found making difficult to chew and swallow. A biopsy showed Kaposi sarcoma associated to HIV/AIDS. The torpid evolution and disease's advanced stage propitiated the patient's death (AU).

Development and validation of RP-HPLC method for simultaneous determination of lamivudine, stavudine, and zidovudine in perfusate samples: Application to the Single-Pass Intestinal Perfusion (SPIP) studies

A reversed-phase high performance liquid chromatography (RP-HPLC) method with ultraviolet detection was developed and validated for the simultaneous quantification of antiretroviral drugs lamivudine (3TC), stavudine (d4T), and zidovudine (AZT) in perfusate samples obtained from the Single-Pass Intestinal Perfusion studies. The chromatographic analysis was performed using a Gemini C18 column and didanosine as internal standard (IS). The following parameters were considered for the validation procedure: system suitability, accuracy, precision, linearity and selectivity. The limits of detection were 0.32 µg/mL for 3TC, 0.11 µg/mL for d4T and 0.45 µg/mL for AZT and the limits of quantification were 1.06 µg/mL for 3TC, 0.38 µg/mL for d4T and 1.51 µg/mL for AZT. Repeatability and intermediate precision ranged from 1.05 to 1.31 and 1.50 to 1.87, respectively, and are expressed as percent of relative standard deviation (RSD). Based on these results, the developed and validated RP-HPLC method can be used for simultaneous determination of 3TC, d4T, and AZT in perfusate samples. Furthermore, this method is simple and adequate for measurements of the antiretroviral drugs in the same sample, since those compounds are mostly co-administered. Besides, this work can be used as an initial base for the development of similar methods in the same conditions presented in our study.

Variables psicosociales predictoras de la no adherencia a los antirretrovirales en personas con VIH-SIDA / Predictive Psychosocial Variables of Non-Adherence to Antiretrovirals in People with HIV-AIDS

Resumen Objetivo: El presente estudio tuvo como objetivo evaluar los niveles de adherencia al tratamiento antirretroviral, así como determinar los factores psicológicos predictores de la no adherencia a dicho tratamiento en pacientes con VIH-SIDA. Método: Diseño descriptivo, transversal y correlacional. La muestra estuvo conformada por 25 personas diagnosticadas con VIH-SIDA que asistieron a los servicios integrales de una asociación civil en la ciudad de Guadalajara, México, y que se encontraban bajo tratamiento antirretroviral. Se utilizó el Cuestionario de adherencia al tratamiento para el VIH-SIDA [CAT-VIH] y el Cuestionario de Factores Relacionados con la Adherencia al Tratamiento para el VIH/SIDA (CFR-AT VIH). Se realizaron análisis descriptivos y no paramétricos para la comparación de las variables de estudio, así como sus respectivas correlaciones. Resultados: Solo 60% de los evaluados presentan una adecuada adherencia al tratamiento con antirretrovirales; además se encontraron diferencias significativas entre adherentes y no adherentes en las variables de autoeficacia (Z=-3.196; p=.001); estrés (Z=-2.033; p=.042); y depresión (Z=-2.409; p=.016). Se obtuvieron correlaciones positivas de la adherencia con autoeficacia (r=.750; p=.000) y apoyo social (r=.462; p=.020) y correlaciones negativas con estrés (r=-.543; p=.005) y depresión (r=-.544; p=.005). Conclusiones: A mayores estados de estrés y depresión, menor serán los niveles de adherencia al tratamiento con antirretrovirales; por lo cual estas variables deben ser tomadas en cuenta para el diseño de estrategias de mejora de la adherencia en personas con VIH-SIDA.

Abstract Objective: Objective: The main aim of this study was to evaluate the levels of adherence to antiretrovirals treatment as well as to determine the psychological factors that predict the non-adherence to antiretrovirals in HIV patients who attend a civil association in Guadalajara, México. Method: It was a descriptive, transversal and correlational design. The sample consisted of 25 patients diagnosed with HIV who attended integral services of a Civil Association. The Adherence to Treatment for HIV/AIDS Questionnaire [CAT-HIV] and the Questionnaire of Factors Related to Adherence to Treatment for HIV/AIDS (CFR-AT HIV) were used. Descriptive and nonparametric analyzes were carried out to compare the study variables, as well as their respective correlations, all through the statistical program SPSS v.20. Results: Only 60% of those evaluated showed adequate adherence to antiretrovirals; in addition, significance differences between adherents and non-adherents in the self-efficacy variable (Z = -3.196, p = .001); stress (Z = -2.033, p = .042); and depression (Z = -2.409, p = .016). Positive correlations of adherence were obtained with self-efficacy (r = .750, p = .000) and social support (r = .462, p = .020) and negative correlations with stress (r = - .543; p = .005) and depression (r = -. 544; p = .005). Conclusions: The higher levels of stress and depression, the lower the levels of adherence to antiretroviral treatment; therefore, these variables must be considered in the design of strategies to improve adherence in people with HIV.

Patterns of Complications of Rhinosinusitis in Sokoto Nigeria

Background: Local or distant spread of paranasal sinus infection can lead to significant morbidity and mortality. Aim: The aim of this study is for audit intent and to determine the patterns of the complications of rhinosinusitis and the management of the complications. Method: A 10-year retrospective chart review of patients who had complications from rhinosinusitis at the Usmanu Danfodiyo University Teaching Hospital, Sokoto, from January 2008 to December 2017. The data extracted were biodata, duration of symptoms, site of paranasal sinus involvement, acute or chronic rhinosinusitis, allergic rhinosinusitis, non-allergic rhinosinusitis, radiological investigations, complications encountered, treatment given and outcome of treatment. Data were analyzed with IBM SPSS version 21.0. Results: The prevalence of the complication of rhinosinusitis in this study was 6.4%. The mean age was 30.9 years and the age range was 9-77 years. There were 31 (47.7%) Males and 34 (52.3%) Females with a Male: Female ratio of 1:1.1. The complications were most common in children and young adults. Non-allergic rhinosinusitis comprised 46 (70.8%) and allergic rhinosinusitis accounted for 19 (29.2%). Computerized tomographic scan of the paranasal sinuses and brain were done for 49 (75.4%) patients and plain X-rays for 16 (24.6) patients. Complications occurred predominantly in chronic rhinosinusitis, which constituted 64 (98.5%) whereas acute rhinosinusitis was responsible for complication in only one patient. The observed complications were most common with multisinusitis 35 (53.8%). Surgical intervention was mainly invasive paranasal sinus surgeries and few functional endoscopic sinus surgeries. Overall, the patients responded well to medical and invasive surgical intervention. Conclusion: The complications were predominant in chronic multisinusitis and occurred exclusively in children and young adults. Paranasal sinus wall and cavity complications were most common. Provision of low cost functional endoscopic sinus surgery is desirable, and it will reduce the number of open and invasive paranasal sinus surgeries.

HIV/AIDS and Its Prevention: A Cross-sectional Study to Evaluate Knowledge, Awareness, and Attitude among Medical Students

Background and Objective: HIV and AIDS is a major global health problem. The lack of knowledge and misconceptions about its modes of transmission among the public, medical students, and healthcare professionals is accountable for the rapid spread of HIV, social stigmatization and discrimination of HIV infected patients. This study aimed to evaluate the knowledge and awareness about HIV and AIDS and also to know the attitude of medical students towards HIV and AIDS patients. Materials and methods: A total of 117 medical students of the 5th year participated voluntarily in this descriptive cross-sectional study. The data was collected in a pretested questionnaire, tabulated and analyzed in Microsoft Excel and SPSS software version 22. The quantitative data were expressed in terms of numbers and percentages. Results: The knowledge among students about HIV is satisfactory. All students (100%) were aware of HIV and AIDS, and its causative agent. The majority of students were aware of modes of transmission, diagnostic tests, and major preventive measures. However, only a few students were aware of the availability of anti-retroviral drugs for treating HIV, few had an erroneous belief that HIV is curable and vaccine-preventable. The study also observed misconceptions among students (12-40%) about spreading of HIV such as by mosquito bite, handshaking, sharing toilets, utensils, and food. Conclusion: From the results of our study, it is suggested that there is a need for an implementation of HIV and AIDS training programs at regular intervals to medical students at the beginning of their inception into a medical course. This would reduce the knowledge, attitude, and practice gap among medical students.

Efectividad y seguridad del esquema genérico lamivudina/tenofovir y efavirenz en pacientes con VIH/SIDA naïve: estudio fase IV no aleatorizado, Cali-Colombia 2012-2014 / Effectiveness and safety of generic version of lamivudine/tenofovir and efavirenz in treatment naïve HIV-infected patients: a nonrandomized, open-label, phase IV study in Cali-Colombia, 2012-2014

Resumen Antecedentes: Los estudios clínicos orientados a evaluar la calidad de medicamentos genéricos pueden ser útiles para fortalecer políticas de acceso a terapia anti-retroviral combinada (TARc). Objetivo: Describir la efectividad y seguridad del esquema genérico lamivudina/tenofovir/efavirenz (3TC/TDF/EFV) en pacientes con infección por VIH/SIDA naïve, pertenecientes a un programa de atención integral. Materiales/Métodos: Estudio clínico prospectivo fase IV abierto y sin grupo control. Entre 2012-2014, se incluyeron y siguieron 40 pacientes con infección por VIH/SIDA naïve y con indicación para iniciar tratamiento. Los pacientes fueron tratados con el esquema genérico 3TC/TDF/EFV y fueron seguidos durante 12 meses. El seguimiento incluyó valoración clínica, parámetros inmunovirológicos y de laboratorio, al inicio del tratamiento y a los 3, 6 y 12 meses. Resultados: De los 40 pacientes, 30 (75%) cumplieron los doce meses de tratamiento; de ellos, 80% alcanzó CV indetectable (< 40 copias/mL) y 83,3% CV < 50 copias/mL. Adicionalmente, en el grupo hubo un incremento en la mediana de 173 linfocitos TCD4/mm3. Por su parte, los resultados del hemograma completo, creatininemia y transaminasas hepáticas se conservaron en rangos normales y no generaron cambios del TARc. Los efectos adversos reconocidos para estos medicamentos se presentaron en menos de 10% de los pacientes y no tuvieron implicaciones graves. Conclusiones: En este grupo pequeño de pacientes, el esquema genérico 3TC/TDF/EFV es efectivo y seguro en el tratamiento de pacientes con infección por VIH/SIDA naïve, y su perfil de efectividad y seguridad es similar al del esquema 3TC/TDF/EFV innovador en pacientes con condiciones clínicas similares.

Background: Clinical studies aimed to evaluating the quality of generic drugs may be useful to strengthen policies of access to combined antiretroviral therapy (cART). Aim: To describe the effectiveness and safety of the generic schema lamivudine/tenofovir/efavirenz (3TC/TDF/EFV) in patients with HIV/AIDS naive, belonging to a comprehensive care program. Methods: A nonrandomized, open-label, phase IV study, during 2012 to 2014 naive HIV-infected patients 18 years or older with indication to receive cART were recruited. Patients were treated with generic scheme 3TC/TDF/EFV and were followed-up during 12 months. Clinical, immunological and laboratory parameters were assessed at baseline, 3, 6 and 12 months of treatment. Results: Of the 40 patients, 30 (75%) met the 12 months of treatment; of them, 80% achieved undetectable viral load (< 40 copies/mL) and 83.3% viral load < 50 copies/mL. Additionally, there was a significant increase (173 cells/mm3) in the median for CD4 T lymphocyte count. Moreover, the results of the whole blood count, creatinine and transaminases were preserved in normal ranges and did not generate changes in the cART. Potential side effects of antiretroviral drugs occurred in less than 10% of patients and had no serious implications. Conclusions: In this small group of patients, the generic scheme 3TC/TDF/EFV is effective and safe in the treatment of patients with HIV/AIDS naïve, and its effectiveness and safety profile is similar to show by innovator scheme 3TC/TDF/EFV in patients with similar clinical conditions. Registro Estudio: Registro Público Cubano de Ensayos Clínicos (RPCEC) ID: RPCEC00000134. Registered 20 July 2012.

Biochemical and Hematological Impact of Hepatitis C Virus (HCV) on Human Immunodeficiency Virus (HIV) Infected Persons on Antiretroviral Drugs (ARDs) in Nigeria

Introduction: Biochemical and hematological abnormalities are among most common clinico-pathological manifestations of HIV/AIDS infected persons on antiretroviral drugs (ARDs). Hepatitis C Virus (HCV) infection are known to influence progression and management of HIV infection. Data are limited regarding the impact of ARDs on HIV/HCV co-infected persons in Nigeria. Hence, this study evaluated the biochemical and hematological impact of HCV on prognosis of HIV persons taking ARDs. Materials and Methods: 2,322 HIV infected persons were screened for HCV. One hundred and nine were co-infected with HCV; and were cross-sectional monitored on ARDs for fifteen months at hospitals in North Central Nigeria for changes in clinical profiles. The determination of Alanine aminotransferase (ALT), Aspartate transaminase (AST), Packed cell volume (PCV) and White blood cells count (WBC) estimations were reviewed every 3 months for each of the person using Reflotron plus machine and hematological analyzer according to the manufacturer抯 instructions. Results: The results showed an increase in both HIV mono-infected and co-infected patients, with raised in AST from 18.46�73 to 34.32�6053U/l, ALT from 19.37�6804 to 34.87�5637U/l, PCV from 34.20�2998 to 34.89�4895% and WBC from 3.50x109�0816 to 6.67x109�1204 cells/L and AST from 17.35�1542 to 34.49�0981U/l, ALT from 17.67�1412 to 34.80�15U/l, PCV from 36.74�2902 to 38.37�4399% and WBC from 3.90x109�0251 to 6.19x109�0178 cells/L. Conclusion: It was found that PCV and WBC count values were positively affected despite HCV replication and AST and ALT enzyme levels for both HIV-mono and co-infected persons were slightly elevated. Therefore, efforts addressing viral hepatitis co-infections at the early stage of ARDs initiation under qualified clinician should be of paramount important.

Prevalence and risk factors of mild chronic renal failure in HIV-infected patients: influence of female gender and antiretroviral therapy

ABSTRACT Background In people living with HIV, much is known about chronic kidney disease, defined as a glomerular filtration rate under 60 mL/min. However, there is scarce data about prevalence and risk factors for milder impairment (60-89 mL/min). Objective The present study aims to assess the influence of sex, antiretroviral therapy, and classical risk factors on the occurrence of mild decreased renal function in a large Spanish cohort of HIV-infected patients. Methods Cross-sectional, single center study, including all adult HIV-1-infected patients under antiretroviral treatment with at least two serum creatinine measures during 2014, describing the occurrence of and the risk factors for mildly decreased renal function (eGFR by CKD-EPI creatinine equation of 60-89 mL/min). Results Among the 4337 patients included, the prevalence rate of mildly reduced renal function was 25%. Independent risk factors for this outcome were age older than 50 years (OR 3.03, 95% CI 2.58-3.55), female sex (OR 1.23, 95% CI 1.02-1.48), baseline hypertension (OR 1.57, 95% CI 1.25-1.97) or dyslipidemia (OR 1.48, 95% CI 1.17-1.87), virologic suppression (OR 1.88, 95% CI 1.39-2.53), and exposure to tenofovir disoproxil-fumarate (OR 1.67, 95% CI 1.33-2.08) or ritonavir-boosted protease-inhibitors (OR 1.19, 95% CI 1.03-1.39). Conclusions Females and patients over 50 seem to be more vulnerable to renal impairment. Potentially modifiable risk factors and exposure to tenofovir disoproxil-fumarate or ritonavir-boosted protease-inhibitors are present even in earlier stages of chronic kidney dysfunction. It remains to be determined whether early interventions including antiretroviral therapy changes (tenofovir alafenamide, cobicistat) or improving comorbidities management will improve the course of chronic kidney disease.

Cost variation among antiretroviral drugs: pharamcoeconomical prospective

Background: Acquired immunodeficiency syndrome (AIDS) is a disorder caused by the human immunodeficiency virus (HIV). Main characteristic feature of AIDS includes severe immunosuppression which leads to opportunistic infections which is a main cause of death and requires a lifelong therapy. There exists wide range of cost variation in antiretroviral drugs that are marketed in India. The current study aims to view the existing situation of antiretroviral drugs, by collecting data about the cost of common antiretroviral drugs available either singly or in combination and to evaluate the difference in cost of different brands of same active drug by calculating percentage cost variation.Methods: Data for calculating cost ratio and percentage price variation of various antiretroviral drugs was obtained from 揅urrent Index of Medical Specialties� October 2017-January2018.Results: Zidovudine 100mg shows maximum cost ratio and price variation followed by Lamivudin 100mg in the single drug therapy. Lamivudine 150mg + Zidovudine 300mg shows maximum price variation in combination drug therapy.Conclusions: Indian market shows wide price variation of different brands of the same generic antiretroviral drug. To decrease the wide cost variation among different brands of antiretroviral drugs; it is time to create awareness among healthcare professionals about impact of cost effectiveness of drug regimen and decrease the financial burden on the patients.

HLA- B*5701 Allele in HIV-infected Indian Children and its Association with Abacavir Hypersensitivit

Objective: To determine the prevalence of HLA-B*5701 allele in HIV-infected children, andtofind its associationwith Abacavir hypersensitivity. Methods: Children (2 to 18 y) already on,or to be initiated on Abacavir were included for PCR sequencing to detect HLA-B*5701.Outcome measures were: proportion with HLA B*5701 allele and hypersensitivity withAbacavir. Abacavir was stopped if patient tested positive for HLA-B*5701 allele. Results:100 children(median age 11 y) were enrolled; 10 were already on Abacavir. HLA-B*5701positivity was observed in 11 (11%) children. Two of these 11 children developedhypersensitivity after initiation of Abacavir. Abacavir was thereafter stopped in all whotested HLA-B*5701 positive, irrespective of the development of hypersensitivity reaction.Conclusion: HLA-B*5701 allele was present in 11 (11%) of HIV-infected children,of whichtwo developed Abacavir hypersensitivity. None of the patients without the allele developedhypersensitivity.

Anti-retroviral drugs: current state and development in the next decade

The pace of discovery of new antiretroviral (ARV) drugs has slowed, although the efficacy and safety of once-daily fixed dose combinations have been extensively investigated. Several traditional ARV drugs remain in phase III clinical trials. This review summarizes current information on ARV drugs in phase III clinical trials and focuses on the development of ARV drugs in the next decade.

Avaliação dos mecanismos envolvidos na permeabilidade de fármacos antirretrovirais por meio do modelo de perfusão in situ em ratos / Evaluation of mechanisms involved in the permeability of antiretroviral drugs using the intestinal in situ perfusion model in rats

Para medicamentos administrados oralmente, as etapas de liberação do fármaco a partir da forma farmacêutica e sua subsequente absorção constituem importantes processos para que a adequada biodisponibilidade oral ocorra. Deste modo, as características de solubilidade e de permeabilidade são de extrema importância para que mecanismos relacionados à absorção sejam compreendidos no âmbito das propriedades ADME (absorção, distribuição, metabolismo e excreção). Com base nisso, o Sistema de Classificação Biofarmacêutica (SCB) foi proposto como uma ferramenta que permite a classificação de fármacos em quatro classes distintas de acordo com a solubilidade e permeabilidade. De maneira complementar, o Sistema de Classificação Biofarmacêutica de Distribuição de Fármacos (SCBDF) foi proposto levando em consideração a solubilidade e o metabolismo das substâncias, além de considerar o impacto de transportadores presentes nos tecidos biológicas, inclusive no trato gastrintestinal (TGI). Assim, o presente trabalho teve como objetivo avaliar os mecanismos envolvidos na permeabilidade de fármacos antirretrovirais (estavudina, lamivudina e zidovudina) por meio do modelo de perfusão in situ com coleta de sangue mesentérico em ratos, considerando os aspectos relacionados ao efluxo e ao metabolismo pré-sistêmico que ocorrem nos enterócitos. Além disso, estudos in vitro em culturas celulares MDCK e MDCK-MDR1 foram realizados a fim de auxiliar na elucidação dos mecanismos de transporte dos referidos fármacos. Para a realização dos estudos de perfusão in situ, ratos Wistar foram anestesiados e a porção do jejuno foi canulada para permitir a entrada do fármaco solubilizado no interior do intestino, bem como a coleta das amostras de perfusato em intervalos regulares de tempo. A veia mesentérica também foi canulada para viabilizar a obtenção das amostras de sangue durante os experimentos. Para os estudos de efluxo, o verapamil foi adicionado à solução de perfusão como inibidor de Pgp (glicoproteína-P), enquanto que o cetoconazol foi empregado como inibidor de enzimas CYP3A. Em modelo in vitro MDCK e MDCK-MDR1, os experimentos foram conduzidos bidirecionalmente com o uso de GG918 como inibidor de P-gp. Em todos os experimentos realizados, o metoprolol e a ranitidina foram empregados como marcadores de alta e de baixa permeabilidade, respectivamente. Os resultados de permeabilidade mostraram que a estavudina e a zidovudina apresentam características de alta permeabilidade, enquanto a lamivudina apresentou o menor resultado dentre os três fármacos. Os ensaios bidirecionais em MDCK, no entanto, mostraram que os três antirretrovirais apresentam baixos valores de permeabilidade, uma vez que seus resultados foram significativamente menores que o valor encontrado para o metoprolol. Com relação à avaliação do mecanismo de efluxo, tanto a lamivudina quanto a zidovudina apresentaram interações significativas com a P-gp nos dois métodos empregados (perfusão in situ e MDCK-MDR1), uma vez que o aumento nos valores de permeabilidade foi constatado quando o inibidor de P-gp foi empregado. Os estudos de metabolismo intestinal realizados por meio do modelo de perfusão in situ mostraram que nenhum dos fármacos antirretrovirais apresentou interação significativa com as enzimas CYP3A quando o cetoconazol foi empregado como inibidor, uma vez que não foram constatadas mudanças significativas nos valores de permeabilidade. A comparação entre os resultados de permeabilidade efetiva (Pef) e de permeabilidade aparente (Pap), obtidos por meio da quantificação das amostras de perfusato e de plasma, respectivamente, permitiu verificar que as diferenças estatísticas entre estes dois parâmetros podem indicar variados mecanismos de transporte, uma vez que a Pap constata a quantidade da substância que realmente foi capaz de superar as barreiras físicas e bioquímicas presentes na parede do TGI. Logo, a Pap é considerada um parâmetro mais próximo das condições in vivo. Esta diferença foi constatada apenas para a zidovudina nos ensaios de transporte de efluxo, uma vez que o valor médio de Pef não representou a mesma conclusão fornecida pelo valor médio de Pap. Os resultados obtidos permitiram concluir que os fármacos antirretrovirais apresentam permeabilidade de moderada a alta em função do possível envolvimento de carreadores de influxo. Além disso, os três fármacos antirretrovirais interagiram de alguma forma com a P-gp, sendo os resultados referentes à lamivudina e à zidovudina mais significativos. Embora tenha sido constatada o envolvimento da P-gp na permeabilidade da zidovudina, sua elevada fração absorvida indica que a absorção desta substância não é limitada por este mecanismo e que a ação do carreador de efluxo não é clinicamente relevante neste caso. Com relação aos estudos de metabolismo, a presença de enzimas CYP3A nos enterócitos também não representou uma condição desfavorável para a absorção dos antirretrovirais. Assim, a avaliação dos mecanismos no presente trabalho contribuiu para a caracterização biofarmacêutica da estavudina, lamivudina e zidovudina e as metodologias descritas podem ser empregadas nas etapas iniciais de desenvolvimento farmacêutico com o objetivo de assegurar a segurança e a eficácia de medicamentos.

For orally administered pharmaceutical products, the drug release from the dosage form and its absorption are considered important processes for adequate oral bioavailability. Thus, the solubility and permeability characteristics are extremely important for understanding of mechanisms related to the absorption in the scope of the ADME properties (absorption, distribution, metabolism and excretion). Based on that, the Biopharmaceutics Classification System (BCS) was proposed as a tool for classifying drugs into four classes considering their solubility and permeability characteristics. In an additional way, the Biopharmaceutics Drug Disposition Classification System (BDDCS) was proposed considering the solubility and metabolism of compounds. Besides, the BDDCS also considers the impact of transporters in biological tissues, such as in the gastrointestinal tract (GIT). Thus, this study aimed to evaluate the mechanisms involved in the permeability of antiretroviral drugs (stavudine, lamivudine and zidovudine) using the intestinal in situ perfusion model with mesenteric blood sampling in rats, considering efflux and intestinal pre-systemic metabolism that occur in the enterocytes. Furthermore, in vitro studies in cell cultures MDCK and MDCK-MDR1 were performed in order to elucidate the transport mechanisms of the drugs. For intestinal in situ perfusion studies, Wistar rats were anesthetized and a portion of jejunum was cannulated to allow the drug entry into the intestine, as well as the perfusate sampling at regular time intervals. The mesenteric vein was also cannulated to allow blood sampling during the experiments. For efflux studies, verapamil was used as P-gp (P-glycoprotein) inhibitor while ketoconazole was used as CYP3A inhibitor. In in vitro model MDCK and MDCK-MDR1, the experiments were performed bidirectionally using GG918 as P-gp inhibitor. For all experiments, metoprolol and ranitidine were used as markers of high and low permeability, respectively. Permeability results showed that stavudine and zidovudine present high permeability characteristics while lamivudine showed the lowest value. However, bidirectional studies in MDCK showed that the antiretroviral drugs present low permeability since their results are far from metoprolol's results. Regarding efflux studies, both lamivudine and zidovudine presented relevant interaction with P-gp in in situ perfusion and MDCK-MDR1 models, since the increase in permeability values was observed when P-gp inhibitor was added. Metabolism studies performed through intestinal in situ perfusion showed that none of antiretroviral drugs interact significantly with CYP3A enzymes, since that no variation in permeability results were noticed. Comparison between effective permeability (Peff) and apparent permeability (Papp), obtained from prefusate and plasma, respectively, allowed to check that statistical differences between these two parameters can indicate different transport mechanisms, since Papp is related to the drug amount that really overcome the physical and biochemical barriers in the gut. Thus, Papp is considered the closest parameter to in vivo condition. This difference was observed for zidovudine in efflux studies, since Peff values does not match with the conclusion provided by the Papp. The results obtained allowed to conclude that the antiretroviral drugs presents moderate to high permeability due to the involvement of influx carriers. Furthermore, the antiretroviral drugs interacted with the P-gp, but lamivudine and zidovudine showed significant results. Although the involvement between zidovudine and P-gp is observed, its high fraction absorbed indicates that the absorption is not limited by efflux transporter, which is not relevant clinically. Regarding 32 metabolism studies, CYP3A enzymes is not considered as a limiting condition for absorption of the antiretroviral drugs. Thus, the evaluation of the mechanisms contributes for biopharmaceutical characterization of stavudine, lamivudine and zidovudine and the methodologies used in this study can be applied in early drug development to ensure adequate safety and efficacy of pharmaceutical products.

Avaliação dos mecanismos envolvidos na permeabilidade de fármacos antirretrovirais por meio dos modelos ex vivo (células de Franz) e in vitro (PAMPA) / Evaluation of mechanisms involved in the permeability of antiretroviral drugs through ex vivo (Franz cells) and in vitro (PAMPA) models

Para fármacos administrados por via oral, o controle da extensão e da velocidade de absorção depende basicamente de duas importantes etapas: solubilidade do fármaco nos líquidos fisiológicos e sua permeabilidade através das membranas biológicas. Assim, o Sistema de Classificação Biofarmacêutica (SCB) foi proposto como uma ferramenta para o desenvolvimento de novos fármacos, de novas formulações e para auxiliar nos processos de bioisenção. No entanto, outro fator relacionado à biodisponibilidade e que deve ser considerado nos estudos biofarmacêuticos é o metabolismo. Desta forma, o Sistema de Classificação Biofarmacêutica de Distribuição de Fármacos (SCBDF) foi proposto com a finalidade de classificar os fármacos de acordo com suas características de solubilidade e de metabolismo de modo que seja possível avaliar e predizer o comportamento do fármaco in vivo. O metabolismo tem sido amplamente investigado, sobretudo as enzimas do citocromo P450, as quais estão presentes também nos enterócitos. Além disso, o SCBDF oferece um suporte quanto à avaliação dos mecanismos de permeabilidade envolvidos nos processos de absorção, interações fármaco-fármaco e interações fármaco-alimento. Assim, o presente trabalho teve como objetivo elucidar os mecanismos envolvidos na permeabilidade de fármacos antirretrovirais por meio dos modelos ex vivo (câmaras de difusão vertical tipo Franz) e in vitro (PAMPA, MDCK-MDR1 e microssomas) considerando os aspectos relacionados ao metabolismo intestinal e ao efluxo destes fármacos. Dada a importância da utilização de fármacos antirretrovirais na terapia medicamentosa contra a Síndrome da Imunodeficiência Adquirida (SIDA) e que estes medicamentos são normalmente administrados cronicamente, a compreensão dos mecanismos envolvidos na permeabilidade é de suma importância, uma vez que estes não estão totalmente esclarecidos e poucas informações são encontradas na literatura. Além disso, a biodisponibilidade de fármacos como estavudina, lamivudina e zidovudina indica variação na permeabilidade, necessitando de uma investigação científica mais aprofundada dos processos absortivos. Assim, segmentos de jejuno provenientes de ratos machos Wistar foram utilizados para a avaliação da permeabilidade intestinal dos referidos antirretrovirais considerando a avaliação de efluxo pela glicoproteína-P e o metabolismo intestinal pela CYP3A. De maneira complementar, estudos in vitro com o emprego de membranas artificiais paralelas (PAMPA) e culturas celulares de MDCK-MDR1 foram realizados com a finalidade de auxiliar na elucidação dos mecanismos de permeabilidade dos fármacos antirretrovirais. Além disso, a avaliação do metabolismo dos referidos fármacos foi realizada com o emprego de microssomas a fim de verificar se tais substâncias são substratos de enzimas da família CYP3A e, assim, verificar o impacto do metabolismo intestinal na absorção. Os resultados de permeabilidade obtidos em PAMPA foram: 0,74±0,11 x 10-6 cm/s para a estavudina, 0,25±0,12 x 10-6 cm/s para a lamivudina e 1,14±0,25 x 10-6 cm/s para a zidovudina. Já no modelo ex vivo com o emprego de câmaras de difusão vertical tipo Franz, os resultados foram: 1,56±0,32 x 10-5 cm/s para a estavudina, 1,26±0,27 x 10-5 cm/s para a lamivudina e 2,54±0,49 x 10-5 cm/s para a zidovudina. Portanto, com base nos resultados obtidos a partir dos dois métodos empregados, sugere-se que 30 outro mecanismo de transporte que não envolva a permeabilidade por difusão transcelular passiva possa estar relacionado à permeabilidade dos fármacos antirretrovirais. Com relação aos estudos de efluxo, os resultados obtidos a partir dos experimentos realizados em câmaras de difusão vertical tipo Franz demonstraram o aumento significativo da permeabilidade dos três antirretrovirais quando o inibidor de P-gp foi empregado, sendo: de 15,6 x 10-6 para 42,5 x 10-6 cm/s para a estavudina, de 12,6 x 10-6 para 37,5 x 10-6 cm/s para a lamivudina e de 25,4 x 10-6 para 56,6 x 10-6 cm/s para a zidovudina. Em culturas celulares MDCK-MDR1, os resultados de permeabilidade foram utilizados para a obtenção das razões entre as direções B→A e A→B. Os valores de Papp na condição inibida para os fármacos estudados apresentaram razão menor do que 1. Já a razão B→A/A→B para cada fármaco nos ensaios sem inibidor apresentou-se igual ou maior que 2, evidenciando a interação fármaco-transportador. Com base nisso, o modelo ex vivo com o emprego de segmentos intestinais em câmaras de difusão vertical tipo Franz apresentou-se adequado na avaliação do mecanismo de efluxo dos fármacos antirretrovirais, o que foi confirmado com os estudos realizados em MDCK-MDR1. Assim, os fármacos antirretrovirais estudados apresentaram interação significativa com a P-gp. Em relação aos estudos de metabolismo realizados em câmaras de difusão vertical tipo Franz, os resultados demonstraram grande variação na permeabilidade dos três antirretrovirais quando o inibidor de CYP3A foi empregado, sendo: de 15,6 x 10-6 para 23,5 x 10-6 cm/s para a estavudina, de 12,6 x 10-6 para 27,3 x 10-6 cm/s para a lamivudina e de 25,4 x 10-6 para 40,5 x 10-6 cm/s para a zidovudina. Já no modelo que emprega microssomas, os resultados de metabolização na ausência e na presença de inibidor de CYP3A foram: de 16,56% para 19,79% para a estavudina, de 14,56% para 15,55% para a lamivudina e de 17,85% para 16,48% para a zidovudina. Com base nisso, sugerese o emprego de microssomas para a determinação de metabolismo, uma vez que o método ex vivo empregado demonstrou grande variação entre os valores obtidos. Desta forma, observou-se que, para cada fármaco, não houve influência significativa no metabolismo pré-sistêmico relacionado às enzimas do complexo CYP3A, o que indica que a absorção oral das referidas substâncias não é limitada por tais enzimas. Portanto, a utilização dos diferentes métodos empregados no desenvolvimento do presente trabalho permitiu compreender os mecanismos envolvidos no transporte dos fármacos antirretrovirais, o que se torna de grande relevância nas etapas de desenvolvimento farmacêutico de novas moléculas e na compreensão de eventos clínicos ainda não esclarecidos atualmente

For orally administered drugs, control of the extent and rate of absorption depends on two important steps: solubility of the drug in physiological liquids and their permeability across biological membranes. Thus, the Biopharmaceutics Classification System (BCS) has been proposed as a tool for the development of new drugs, new formulations and aid in the biowaiver processes. However, another factor related to bioavailability that should be considered in biopharmaceutic studies is the metabolism. Thus, the Biopharmaceutics Drug Disposition Classification System (BDDCS) has been proposed for drug classification according to their solubility and metabolism characteristics, so it is possible to evaluate and predict the in vivo behavior of a compound. Metabolism has been extensively investigated, especially cytochrome P450 enzymes, which are also expressed in enterocytes. Besides, BDDCS provides support in evaluating the permeability mechanisms involved in the absorption processes, drug-drug interactions and drug-food interactions. Thus, the present study aimed to evaluate the mechanisms of permeability of antiretroviral drugs through the ex vivo (Franz cells) and in vitro (PAMPA, MDCK-MDR1 and microsomes) models considering aspects related to the intestinal metabolism and efflux of these drugs. Given the importance of the use of antiretroviral drugs in drug therapy against Acquired Immune Deficiency Syndrome (AIDS) and that these drugs are usually administered in a long-term way, understanding the mechanisms involved in the permeability is of a great importance, since they are not totally elucidated and no information is found in the literature. In addition, drugs as stavudine, lamivudine and zidovudine indicate variation in the permeability, which require further scientific investigation of absorptive processes. Thus, jejunum segments from rats were used to evaluate the intestinal permeability of these antiretroviral drugs, considering the evaluation of efflux by P-glycoprotein and intestinal metabolism by CYP3A. In a complementary manner, in vitro studies using parallel artificial membranes (PAMPA) and cell cultures MDCK-MDR1 were performed to aid in the elucidation of the permeability mechanisms of antiretroviral drugs. Also, the evaluation of the metabolism was carried out using microsomes to verify if such substances are substrates of CYP3A, and verify the impact of the intestinal metabolism in the absorption. The permeability results obtained in PAMPA were: 0.74±0.11x10-6 cm/s for stavudine, 0.25±0.12x10-6 cm/s for lamivudine and 1.14±0.25x10-6 cm/s for zidovudine. In ex vivo method using the intestinal segments in Franz cells, the results were: 1.56±0.32x10-5 cm/s for stavudine, 1.26±0.27x10-5 cm/s for lamivudine and 2.54±0.49x10-5 cm/s for zidovudine. Thus, based on the results obtained from these two methods, it is suggested that the antiretroviral drugs present other transport mechanism that is different from transcellular passive diffusion. For efflux studies, results obtained from experiments performed in Franz cells shown the increase of the permeability of the three antiretroviral drugs when the P-gp inhibitor was used: from 15.6x10-6 to 42,5x10-6 cm/s for stavudine, from 12.6x10-6 cm/s to 37.5x10-6 cm/s for lamivudine, and 25.4x10-6 to 56.6x10-6 cm/s for zidovudine. In MDCK-MDR1, the permeability results were used for obtaining ratio values between the directions B→A and A→B. The Papp values obtained with 33 inhibitor shown a ratio less than 1. For ratio B→A/A→B for each drug in experiments without inhibitor, the values obtained was equal or greater than 2, which shows the interaction between drug and transporter. Based on that, the ex vivo model using intestinal segments in Franz cells seems to be adequate for evaluation of efflux mechanism of antiretroviral drugs, which was confirmed by MDCK-MDR1 studies. Thus, the antiretroviral drugs presented interaction with P-gp. For metabolism studies in intestinal segments in Franz cells, a wide range of standard deviation was observed for the three antiretroviral drugs when the CYP3A inhibitor was used: from 15.6x10-6 cm/s to 23.5x10-6 cm/s for stavudine, from 12.6x10-6 cm/s to 27.3x10-6 cm/s for lamivudine, and from 25.4x10-6 cm/s to 40.5x10-6 cm/s for zidovudine. In experiments in microsomes, the results of metabolization in the absence and presence of CYP3A inhibitor were: from 16.56 to 19.79% for stavudine, from 14.56 to 15.55% for lamivudine and from 17.85 to 16.48% for zidovudine. Based on that, it is suggested the use of microsomes for metabolism evaluation, since the ex vivo method presented high variability between the results obtained. For each drug, no significative influence in pre-systemic metabolism related to CYP3A enzymes was observed, which indicates that the oral absorption of the drugs is not limited by these enzymes. The use of different methods in this work allowed to understand the mechanisms involved in the transport of antiretroviral drugs, which is of a great relevance in drug development and in the understanding of clinical events currently not clarified

Avaliação dos mecanismos envolvidos na permeabilidade de fármacos antirretrovirais por meio dos modelos ex vivo ( células de Franz ) e in vitro ( PAMPA ) / Evaluation of mechanisms involved in the permeability of antiretroviral drugs through ex vivo ( Franz cells ) and in vitro ( PAMPA ) models

Para fármacos administrados por via oral, o controle da extensão e da velocidade de absorção depende basicamente de duas importantes etapas: solubilidade do fármaco nos líquidos fisiológicos e sua permeabilidade através das membranas biológicas. Assim, o Sistema de Classificação Biofarmacêutica (SCB) foi proposto como uma ferramenta para o desenvolvimento de novos fármacos, de novas formulações e para auxiliar nos processos de bioisenção. No entanto, outro fator relacionado à biodisponibilidade e que deve ser considerado nos estudos biofarmacêuticos é o metabolismo. Desta forma, o Sistema de Classificação Biofarmacêutica de Distribuição de Fármacos (SCBDF) foi proposto com a finalidade de classificar os fármacos de acordo com suas características de solubilidade e de metabolismo de modo que seja possível avaliar e predizer o comportamento do fármaco in vivo. O metabolismo tem sido amplamente investigado, sobretudo as enzimas do citocromo P450, as quais estão presentes também nos enterócitos. Além disso, o SCBDF oferece um suporte quanto à avaliação dos mecanismos de permeabilidade envolvidos nos processos de absorção, interações fármaco-fármaco e interações fármaco-alimento. Assim, o presente trabalho teve como objetivo elucidar os mecanismos envolvidos na permeabilidade de fármacos antirretrovirais por meio dos modelos ex vivo (câmaras de difusão vertical tipo Franz) e in vitro (PAMPA, MDCK-MDR1 e microssomas) considerando os aspectos relacionados ao metabolismo intestinal e ao efluxo destes fármacos. Dada a importância da utilização de fármacos antirretrovirais na terapia medicamentosa contra a Síndrome da Imunodeficiência Adquirida (SIDA) e que estes medicamentos são normalmente administrados cronicamente, a compreensão dos mecanismos envolvidos na permeabilidade é de suma importância, uma vez que estes não estão totalmente esclarecidos e poucas informações são encontradas na literatura. Além disso, a biodisponibilidade de fármacos como estavudina, lamivudina e zidovudina indica variação na permeabilidade, necessitando de uma investigação científica mais aprofundada dos processos absortivos. Assim, segmentos de jejuno provenientes de ratos machos Wistar foram utilizados para a avaliação da permeabilidade intestinal dos referidos antirretrovirais considerando a avaliação de efluxo pela glicoproteína-P e o metabolismo intestinal pela CYP3A. De maneira complementar, estudos in vitro com o emprego de membranas artificiais paralelas (PAMPA) e culturas celulares de MDCK-MDR1 foram realizados com a finalidade de auxiliar na elucidação dos mecanismos de permeabilidade dos fármacos antirretrovirais. Além disso, a avaliação do metabolismo dos referidos fármacos foi realizada com o emprego de microssomas a fim de verificar se tais substâncias são substratos de enzimas da família CYP3A e, assim, verificar o impacto do metabolismo intestinal na absorção. Os resultados de permeabilidade obtidos em PAMPA foram: 0,74±0,11 x 10-6 cm/s para a estavudina, 0,25±0,12 x 10-6 cm/s para a lamivudina e 1,14±0,25 x 10-6 cm/s para a zidovudina. Já no modelo ex vivo com o emprego de câmaras de difusão vertical tipo Franz, os resultados foram: 1,56±0,32 x 10-5 cm/s para a estavudina, 1,26±0,27 x 10-5 cm/s para a lamivudina e 2,54±0,49 x 10-5 cm/s para a zidovudina. Portanto, com base nos resultados obtidos a partir dos dois métodos empregados, sugere-se que 30 outro mecanismo de transporte que não envolva a permeabilidade por difusão transcelular passiva possa estar relacionado à permeabilidade dos fármacos antirretrovirais. Com relação aos estudos de efluxo, os resultados obtidos a partir dos experimentos realizados em câmaras de difusão vertical tipo Franz demonstraram o aumento significativo da permeabilidade dos três antirretrovirais quando o inibidor de P-gp foi empregado, sendo: de 15,6 x 10-6 para 42,5 x 10-6 cm/s para a estavudina, de 12,6 x 10-6 para 37,5 x 10-6 cm/s para a lamivudina e de 25,4 x 10-6 para 56,6 x 10-6 cm/s para a zidovudina. Em culturas celulares MDCK-MDR1, os resultados de permeabilidade foram utilizados para a obtenção das razões entre as direções B→A e A→B. Os valores de Papp na condição inibida para os fármacos estudados apresentaram razão menor do que 1. Já a razão B→A/A→B para cada fármaco nos ensaios sem inibidor apresentou-se igual ou maior que 2, evidenciando a interação fármaco-transportador. Com base nisso, o modelo ex vivo com o emprego de segmentos intestinais em câmaras de difusão vertical tipo Franz apresentou-se adequado na avaliação do mecanismo de efluxo dos fármacos antirretrovirais, o que foi confirmado com os estudos realizados em MDCK-MDR1. Assim, os fármacos antirretrovirais estudados apresentaram interação significativa com a P-gp. Em relação aos estudos de metabolismo realizados em câmaras de difusão vertical tipo Franz, os resultados demonstraram grande variação na permeabilidade dos três antirretrovirais quando o inibidor de CYP3A foi empregado, sendo: de 15,6 x 10-6 para 23,5 x 10-6 cm/s para a estavudina, de 12,6 x 10-6 para 27,3 x 10-6 cm/s para a lamivudina e de 25,4 x 10-6 para 40,5 x 10-6 cm/s para a zidovudina. Já no modelo que emprega microssomas, os resultados de metabolização na ausência e na presença de inibidor de CYP3A foram: de 16,56% para 19,79% para a estavudina, de 14,56% para 15,55% para a lamivudina e de 17,85% para 16,48% para a zidovudina. Com base nisso, sugerese o emprego de microssomas para a determinação de metabolismo, uma vez que o método ex vivo empregado demonstrou grande variação entre os valores obtidos. Desta forma, observou-se que, para cada fármaco, não houve influência significativa no metabolismo pré-sistêmico relacionado às enzimas do complexo CYP3A, o que indica que a absorção oral das referidas substâncias não é limitada por tais enzimas. Portanto, a utilização dos diferentes métodos empregados no desenvolvimento do presente trabalho permitiu compreender os mecanismos envolvidos no transporte dos fármacos antirretrovirais, o que se torna de grande relevância nas etapas de desenvolvimento farmacêutico de novas moléculas e na compreensão de eventos clínicos ainda não esclarecidos atualmente

For orally administered drugs, control of the extent and rate of absorption depends on two important steps: solubility of the drug in physiological liquids and their permeability across biological membranes. Thus, the Biopharmaceutics Classification System (BCS) has been proposed as a tool for the development of new drugs, new formulations and aid in the biowaiver processes. However, another factor related to bioavailability that should be considered in biopharmaceutic studies is the metabolism. Thus, the Biopharmaceutics Drug Disposition Classification System (BDDCS) has been proposed for drug classification according to their solubility and metabolism characteristics, so it is possible to evaluate and predict the in vivo behavior of a compound. Metabolism has been extensively investigated, especially cytochrome P450 enzymes, which are also expressed in enterocytes. Besides, BDDCS provides support in evaluating the permeability mechanisms involved in the absorption processes, drug-drug interactions and drug-food interactions. Thus, the present study aimed to evaluate the mechanisms of permeability of antiretroviral drugs through the ex vivo (Franz cells) and in vitro (PAMPA, MDCK-MDR1 and microsomes) models considering aspects related to the intestinal metabolism and efflux of these drugs. Given the importance of the use of antiretroviral drugs in drug therapy against Acquired Immune Deficiency Syndrome (AIDS) and that these drugs are usually administered in a long-term way, understanding the mechanisms involved in the permeability is of a great importance, since they are not totally elucidated and no information is found in the literature. In addition, drugs as stavudine, lamivudine and zidovudine indicate variation in the permeability, which require further scientific investigation of absorptive processes. Thus, jejunum segments from rats were used to evaluate the intestinal permeability of these antiretroviral drugs, considering the evaluation of efflux by P-glycoprotein and intestinal metabolism by CYP3A. In a complementary manner, in vitro studies using parallel artificial membranes (PAMPA) and cell cultures MDCK-MDR1 were performed to aid in the elucidation of the permeability mechanisms of antiretroviral drugs. Also, the evaluation of the metabolism was carried out using microsomes to verify if such substances are substrates of CYP3A, and verify the impact of the intestinal metabolism in the absorption. The permeability results obtained in PAMPA were: 0.74±0.11x10-6 cm/s for stavudine, 0.25±0.12x10-6 cm/s for lamivudine and 1.14±0.25x10-6 cm/s for zidovudine. In ex vivo method using the intestinal segments in Franz cells, the results were: 1.56±0.32x10-5 cm/s for stavudine, 1.26±0.27x10-5 cm/s for lamivudine and 2.54±0.49x10-5 cm/s for zidovudine. Thus, based on the results obtained from these two methods, it is suggested that the antiretroviral drugs present other transport mechanism that is different from transcellular passive diffusion. For efflux studies, results obtained from experiments performed in Franz cells shown the increase of the permeability of the three antiretroviral drugs when the P-gp inhibitor was used: from 15.6x10-6 to 42,5x10-6 cm/s for stavudine, from 12.6x10-6 cm/s to 37.5x10-6 cm/s for lamivudine, and 25.4x10-6 to 56.6x10-6 cm/s for zidovudine. In MDCK-MDR1, the permeability results were used for obtaining ratio values between the directions B→A and A→B. The Papp values obtained with 33 inhibitor shown a ratio less than 1. For ratio B→A/A→B for each drug in experiments without inhibitor, the values obtained was equal or greater than 2, which shows the interaction between drug and transporter. Based on that, the ex vivo model using intestinal segments in Franz cells seems to be adequate for evaluation of efflux mechanism of antiretroviral drugs, which was confirmed by MDCK-MDR1 studies. Thus, the antiretroviral drugs presented interaction with P-gp. For metabolism studies in intestinal segments in Franz cells, a wide range of standard deviation was observed for the three antiretroviral drugs when the CYP3A inhibitor was used: from 15.6x10-6 cm/s to 23.5x10-6 cm/s for stavudine, from 12.6x10-6 cm/s to 27.3x10-6 cm/s for lamivudine, and from 25.4x10-6 cm/s to 40.5x10-6 cm/s for zidovudine. In experiments in microsomes, the results of metabolization in the absence and presence of CYP3A inhibitor were: from 16.56 to 19.79% for stavudine, from 14.56 to 15.55% for lamivudine and from 17.85 to 16.48% for zidovudine. Based on that, it is suggested the use of microsomes for metabolism evaluation, since the ex vivo method presented high variability between the results obtained. For each drug, no significative influence in pre-systemic metabolism related to CYP3A enzymes was observed, which indicates that the oral absorption of the drugs is not limited by these enzymes. The use of different methods in this work allowed to understand the mechanisms involved in the transport of antiretroviral drugs, which is of a great relevance in drug development and in the understanding of clinical events currently not clarified

Recent Advances of Antiretroviral Agents / 대한내과학회지

The treatment of human immunodeficiency virus is under constant development. This report reviews recent advances in antiretroviral agents.

Reacciones adversas más frecuentes de los fármacos antirretrovirales

Introducción: las reacciones adversas a los antirretrovirales constituyen un obstáculo para el cumplimiento y la buena adherencia, debido a la gravedad que pueden alcanzar estos efectos, al abandono del tratamiento y/o remplazo del fármaco en cuestión. Objetivos: describir las reacciones a antirretrovirales más frecuentemente observadas. Pacientes y métodos: diseño observacional retrospectivo realizado en varones y mujeres, mayores de edad, portadores de HIV, que consultaron en el Servicio de Atención Integral del Hospital Nacional entre noviembre de 2007 y diciembre 2012. Resultados: fueron incluidos 190 pacientes, en 59 casos (31%) se presentaron efectos secundarios al TARGA. La edad media fue 35 años (rango 19-63 años). El 62,2% de los sujetos correspondían al sexo masculino. Predominaron las manifestaciones neuropsicológicas (28%), dermatológicas (22%) y hematológicas (21%).

Introduction: Adverse reactions to antiretroviral drugs are obstacles for the compliance and good adherence because of their severity, the treatment dropouts and/or the replacement of the drug. Objective: To describe the most frequently observed adverse reactions to antiretroviral drugs. Patients and methods: Retrospective observational design carried out in adult men and women, HIV carriers, who attended the Comprehensive Care Service between November, 2007 and December, 2012. Results: One hundred ninety patients were included and 59 cases (31%) presented side-effects to HAART. Mean age was 35 years (range: 19-63 years) and 62.2% of the subjects were men. Neuropsychological (28%), dermatologic (22%) and hematologic (21%) manifestations predominated.

Evolución rápida de la resistencia a drogas antirretrovirales en 2 pacientes infectados por VIH-1 / Rapid development of resistance to antiretroviral drugs in two patients infected with HIV-1

Introducción: el empleo de la terapia antirretroviral ha facilitado la recuperación lenta y parcial del sistema inmune, lo que permite reducir las complicaciones oportunistas, incrementar la supervivencia y mejorar la calidad de vida en pacientes infectados por el virus de inmunodeficiencia humana tipo 1. Objetivo: determinar las variantes virales de evolución rápida a la resistencia a drogas antirretrovirales en pacientes positivos a VIH-1. Métodos: se estudiaron 2 pacientes positivos a VIH-1; se nombraron con las letras A y B, respectivamente, y se les determinó la resistencia a drogas antirretrovirales en 2 tiempos diferentes: momento del diagnóstico y 2012. Los resultados se relacionaron con variables clínicas. Resultados: el paciente A, en el momento del diagnóstico, presentó un virus subtipo BG con niveles bajos de resistencia a zidovudina y estavudina y el B, virus subtipo B, con bajos niveles de resistencia a zidovudina. En el año 2012, el paciente A mostró una variante viral FRC18_cpx con altos niveles de resistencia a lamivudina, emtricitabina y nevirapina. El paciente B se mantuvo infectado con un virus subtipo B, pero resistente a los inhibidores de la transcriptasa inversa. Conclusiones: estos resultados muestran la dinámica y rápida evolución de las variantes de VIH-1 en pacientes infectados...

Introduction: the use of antiretroviral therapy has facilitated the slow and partial recovery of the immune system, allowing to reduce opportunistic complications, to increase survival and to improve quality of life in patients infected with human immunodeficiency virus type 1. Objective: to determine rapid evolving viral variants with resistance to antiretroviral drugs in HIV-1 positive patients. Methods: two HIV-1 positive patients were studied. They were appointed by the letters A and B, respectively, and antiretroviral drug resistance were determined at two different times: Moment of diagnosis and 2012. Results were related to clinical variables. Results: at the time of diagnosis Patient A had subtype BG virus with low levels of resistance to zidovudine and stavudine. Patient B had subtype B virus with low levels of resistance to zidovudine. In 2012, the patient A showed FRC18-cpx viral variant with high levels of resistance to lamivudine, emtricitabine, and nevirapine. Patient B remained infected with subtype B virus, but resistant to the reverse transcriptase inhibitors. Conclusions: these results show the dynamic and rapidly evolving variants of HIV-1 infected patients...