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1.
Arq. ciências saúde UNIPAR ; 27(2): 556-573, Maio-Ago. 2023.
Artículo en Portugués | LILACS | ID: biblio-1419200

RESUMEN

Objetivo: avaliar a eficácia da Ivermectina e do Atazanavir em comparação com placebo no tempo de resolução dos sintomas e no tempo de duração da doença por COVID-19. Método: estudo observacional, de coorte prospectivo, longitudinal, descritivo e analítico com pacientes sintomáticos ambulatoriais, acompanhados por 06 meses em duas Unidades Básicas de Saúde para atendimento de COVID-19 em Teresina- Piauí, Brasil, no período de novembro a abril de 2021 identificados por amostragem aleatória 1:1:1. Foram realizados exames Reverse transcription polymerase chain reaction (RT-PCR) para confirmação laboratorial da suspeita de infecção pelo novo coronavírus e avaliação sociodemográfica e clínica. Resultados: dos 87 pacientes randomizados, 62,1% (n=54) eram do sexo masculino, com média de idade de 35,1 anos, possuíam companheira (53,9%), baixa renda (50,6%), eutróficos (40,7%) e sem comorbidades de saúde (78,2%). Não houve diferença entre o tempo médio para resolução dos sintomas, que foi de 21 dias (IQR, 8-30) no grupo atazanavir, 30 dias (IQR, 5-90) no grupo ivermectina em comparação com 14 dias (IQR, 9-21) no grupo controle. No dia 180, houve resolução dos sintomas em 100% no grupo placebo, 93,9% no grupo atazanavir e 95% no grupo ivermectina. A duração mediana da doença foi de 08 dias em todos os braços do estudo. Conclusão: o tratamento com atazanavir (6 dias) e ivermectina (3 dias) não reduziu o tempo de resolução dos sintomas e nem o tempo de duração da doença entre os pacientes ambulatoriais com COVID-19 leve em comparação com o grupo placebo. Os resultados não suportam o uso de ivermectina e atazanavir para tratamento de COVID-19 leve a moderado.


Objective: to evaluate the effectiveness of Ivermectin and Atazanavir compared to placebo in the time to resolution of symptoms and duration of illness due to COVID-19. Method: observational, prospective, longitudinal, descriptive and analytical cohort study with symptomatic outpatients, followed for 06 months in two Basic Health Units for COVID-19 care in Teresina-Piauí, Brazil, from November to April 2021 identified by 1:1:1 random sampling. Reverse transcription polymerase chain reaction (RT-PCR) tests were performed for laboratory confirmation of suspected infection with the new coronavirus and sociodemographic and clinical evaluation. Results: of the 87 randomized patients, 62.1% (n=54) were male, with a mean age of 35.1 years, had a partner (53.9%), low income (50.6%), eutrophic (40.7%) and without health comorbidities (78.2%). There was no difference between the median time to resolution of symptoms, which was 21 days (IQR, 8-30) in the atazanavir group, 30 days (IQR, 5- 90) in the ivermectin group compared with 14 days (IQR, 9- 21) in the control group. At day 180, there was resolution of symptoms in 100% in the placebo group, 93.9% in the atazanavir group, and 95% in the ivermectin group. The median duration of illness was 8 days in all study arms. Conclusion: Treatment with atazanavir (6 days) and ivermectin (3 days) did not reduce the time to symptom resolution or the duration of illness among outpatients with mild COVID-19 compared to the placebo group. The results do not support the use of ivermectin and atazanavir for the treatment of mild to moderate COVID-19.


Objetivo: evaluar la efectividad de Ivermectina y Atazanavir en comparación con placebo en el tiempo de resolución de los síntomas y duración de la enfermedad por COVID-19. Método: estudio de cohorte observacional, prospectivo, longitudinal, descriptivo y analítico con pacientes ambulatorios sintomáticos, seguidos durante 06 meses en dos Unidades Básicas de Salud para atención de COVID-19 en Teresina-Piauí, Brasil, de noviembre a abril de 2021 identificados por 1:1:1 muestreo aleatorio. Se realizaron pruebas de reacción en cadena de la polimerasa con transcriptasa inversa (RT-PCR) para confirmación de laboratorio de sospecha de infección por el nuevo coronavirus y evaluación sociodemográfica y clínica. Resultados: de los 87 pacientes aleatorizados, 62,1% (n=54) eran del sexo masculino, con una edad media de 35,1 años, tenían pareja (53,9%), bajos ingresos (50,6%), eutróficos (40,7%) y sin comorbilidades de salud (78,2%). No hubo diferencia entre la mediana de tiempo hasta la resolución de los síntomas, que fue de 21 días (RIC, 8-30) en el grupo de atazanavir, 30 días (RIC, 5- 90) en el grupo de ivermectina en comparación con 14 días (RIC, 9 - 21) en el grupo control. En el día 180, hubo una resolución de los síntomas del 100 % en el grupo de placebo, del 93,9 % en el grupo de atazanavir y del 95 % en el grupo de ivermectina. La mediana de duración de la enfermedad fue de 8 días en todos los brazos del estudio. Conclusión: El tratamiento con atazanavir (6 días) e ivermectina (3 días) no redujo el tiempo de resolución de los síntomas ni la duración de la enfermedad entre los pacientes ambulatorios con COVID-19 leve en comparación con el grupo placebo. Los resultados no respaldan el uso de ivermectina y atazanavir para el tratamiento de la COVID-19 de leve a moderada.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Ivermectina/análisis , Eficacia , Sulfato de Atazanavir/análisis , COVID-19/complicaciones , COVID-19/tratamiento farmacológico , Pacientes Ambulatorios , Estudios Prospectivos , Estudios de Cohortes , Ensayos Clínicos como Asunto/métodos , Estudios Observacionales como Asunto/métodos
2.
Actual. SIDA. infectol ; 31(112): 9-16, 20230000. graf, tab
Artículo en Español | LILACS, BINACIS | ID: biblio-1451535

RESUMEN

Antecedentes: La terapia dual ha surgido como un nuevo concepto para el tratamiento del VIH. Este estudio tenía como objetivo comparar un régimen dual basado en ATV/r + RAL (TD) frente a estándar de tres drogas con ATV/r + TDF/FTC (TT) luego del fracaso de un primer esquema ba-sado en INNTR.ClinicalTrials.gov, Número: NCT01829802.Método: Estudio piloto abierto, multicéntrico y aleatoriza-do. Resultado primario: proporción de sujetos con ARN del VIH-1 menor a 50 copias/mL en semana 48 (S48). Resulta-dos secundarios: discontinuaciones asociadas a eventos adversos (EA), tiempo transcurrido hasta la supresión viral, desarrollo de mutaciones de resistencia a la integrasa y proteasa, cambio en recuento de CD4. Resultados: De los 57 participantes seleccionados, 34 fue-ron asignados aleatoriamente para recibir: TD (n: 18) o TT (n: 16). En semana 48, 67% (n: 12/18) en TD tuvo respues-ta virológica y 88% (n: 14/16) en rama según el análisis FDA, intención de tratamiento/expuestos (p = NS) y 73% (TD) y 93% (TT) según análisis por protocolo (p = NS). El cambio de CD4 entre basal - S48: +119 y +52 células/µL en DT y TT, respectivamente. Cuatro participantes en TD y uno en TT presentaron fracaso virológico en la semana 48. Un participante desarrolló una mutación de resistencia a integrasa (155H).Conclusión: ATV/r+RAL como terapia dual de segunda línea mostró una tendencia al fracaso virológico más frecuente, en comparación con TT, aunque el estudio piloto no tenía potencia para demostrar esta diferencia. Este estudio está registrado en ClinicalTrials.gov, Número: NCT01829802


Background: Dual therapy has emerged as a novel concept for HIV treatment. This study was aimed at comparing a nucleoside-sparing dual regimen consisting of ATV/r + RAL (DT) vs standard therapy of ATV/r + TDF/FTC (TT) among individuals failing first NNRTI-containing treatment.Methods: Randomized multicenter open-label pilot study. Primary outcome: proportion of subjects with plasma HIV-1 RNA below the limit of detection (<50 copies/mL) at 48 weeks (W48). Secondary outcomes: proportion of discontinuation due to adverse events (AEs), time until viral suppression, time until loss of virological response, development of integrase resistance mutations, and absolute change in CD4 counts. The primary outcome was analyzed using the FDA snapshot analysis.Results: Out of 57 participants screened, 34 were randomized to receive: DT (n: 18) or TT (n: 16). At W48, virological response was achieved in 67% (n: 12/18) of participants receiving DT and 88% (n: 14/16) receiving TT by FDA snapshot analysis (p = NS) and 73% and 93% by per-protocol analysis (p = NS). CD4 cell count median change from baseline to W48 was +119 and + 52 cell/µL in DT and TT, respectively. Four participants receiving DT and one TT presented virological failure at W48, with low pVL. One participant developed an integrase resistance mutation (155H) and suppressed later on TT.Conclusion: ATV/r+RAL as second-line therapy showed a trend to more frequent virological failure, compared to TT, although the study was unpowered to prove this difference. No major differences were seen in tolerance or toxicity.This study is registered with ClinicalTrials.gov, Number: NCT01829802


Asunto(s)
Humanos , Masculino , Femenino , Ritonavir/uso terapéutico , Terapia Antirretroviral Altamente Activa , Sulfato de Atazanavir/uso terapéutico
3.
Lancet Reg Health Am ; 20: 100466, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36908503

RESUMEN

Background: Repurposed drugs for treatment of new onset disease may be an effective therapeutic shortcut. We aimed to evaluate the efficacy of repurposed antivirals compared to placebo in lowering SARS-CoV2 viral load of COVID-19 patients. Methods: REVOLUTIOn is a randomised, parallel, blinded, multistage, superiority and placebo controlled randomised trial conducted in 35 centres in Brazil. We include patients aged 18 years or older admitted to hospital with laboratory-confirmed SARS-CoV-2 infection, symptoms onset 9 days or less and SpO2 94% or lower at room air were eligible. All participants were randomly allocated to receive either atazanavir, daclatasvir or sofosbuvir/daclatasvir or placebo for 10 days. The primary outcome was the decay rate (slope) of the SARS-CoV-2 viral load logarithm assessed in the modified intention to-treat population. This trial was registered with ClinicalTrials.gov, number NCT04468087. Findings: Between February 09, 2021, and August 04, 2021, 255 participants were enrolled and randomly assigned to atazanavir (n = 64), daclatasvir (n = 66), sofosbuvir/daclatasvir (n = 67) or placebo (n = 58). Compared to placebo group, the change from baseline to day 10 in log viral load was not significantly different for any of the treatment groups (0.05 [95% CI, -0.03 to 0.12], -0.02 [95% CI, -0.09 to 0.06], and -0.03 [95% CI, -0.11 to 0.04] for atazanavir, daclatasvir and sofosbuvir/daclatasvir groups respectively). There was no significant difference in the occurrence of serious adverse events between treatment groups. Interpretation: No significant reduction in viral load was observed from the use of atazanavir, daclatasvir or sofosbuvir/daclatasvir compared to placebo in hospitalised COVID-19 patients who need oxygen support with symptoms onset 9 days or less. Funding: Ministério da Ciência, Tecnologia e Inovação (MCTI) - Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPQ); Cia Latino-Americana de Medicamentos (Clamed); Cia Industrial H. Carlos Schneider (Ciser); Hospital Research Foundation Incorporation, Australia, HCor São Paulo; Blanver Farmoquímica; Instituto de Tecnologia em Fármacos (Farmanguinhos) da Fundação Oswaldo Cruz (Fiocruz); Coordenação Geral de Planejamento Estratégico (Cogeplan)/Fiocruz; and Fundação de apoio a Fiocruz (Fiotec, VPGDI-054-FIO-20-2-13).

4.
Arq. ciências saúde UNIPAR ; 27(3): 1128-2023, 2023.
Artículo en Portugués | LILACS | ID: biblio-1425430

RESUMEN

Objetivo: Examinar e mapear as evidências científicas sobre a eficácia do uso de ivermectina e atazanavir no tratamento de COVID-19. Metodologia: Scoping Review, baseado nos procedimentos recomendados pelo Instituto Joanna Briggs. Estabeleceu-se a pergunta norteadora: "Quais são as evidências científicas sobre o uso de ivermectina e atazanavir no tratamento de pacientes com sintomas leves de COVID-19?". Foram realizadas buscas em seis bases de dados nacionais e internacionais, sobre trabalhos publicados até dezembro de 2022. Dos 357 estudos encontrados, 22 foram selecionados para leitura na íntegra, resultando em uma amostra final de 11 estudos analisados. Resultados: As 11 publicações analisadas foram publicadas de 2020 a 2022 durante período pandêmico, de âmbito nacional e internacional com delineamento de estudos experimentais, do tipo ensaio clínico com randomização. Apenas 03 estudos (25%) testaram o atazanavir como intervenção conjugada a outras drogas, não evidenciando melhorias significativas em relação ao seu uso. Já no tratamento com Ivermectina, dos oito (75%) estudos que a testaram, apenas três (37,5%) recomendaram seu uso e cinco (62,5%) não suportam seu uso para tratamento de COVID-19 leve. O tempo de resolução dos sintomas variou de 8 a 10 dias nos braços tratados com ivermectina e em média 07 dias no tratamento com atazanavir. Não se detectou eventos adversos graves relacionados ao uso das duas drogas. Conclusão: As evidências que recomendavam o uso de ivermectina datam do início do período pandêmico, 2020, mas posteriormente, com a realização de ensaios clínicos robustos e controlados, novas evidências não suportam o uso de ivermectina e atazanavir no tratamento de COVID-19 leve mostrando que não houve diferença no tempo de resolução dos sintomas, na taxa de mortalidade, taxa de internação na UTI e tempo de hospitalização.


Objective: To examine and map the scientific evidence on the effectiveness of using ivermectin and atazanavir in the treatment of COVID-19. Methodology: Scoping Review, based on the procedures recommended by the Joanna Briggs Institute. The guiding question was established, "What is the scientific evidence on the use of ivermectin and atazanavir in the treatment of patients with mild symptoms of COVID-19?" Searches were conducted in six national and international databases on papers published until December 2022. Of the 357 studies found, 22 were selected for reading in full, resulting in a final sample of 11 studies analyzed. Results: The 11 publications analyzed were published from 2020 to 2022 during pandemic period, of national and international scope with experimental study design, of clinical trial type with randomization. Only 03 studies (25%) tested atazanavir as a combined intervention with other drugs, showing no significant improvements in relation to its use. As for the treatment with Ivermectin, of the eight (75%) studies that tested it, only three (37.5%) recommended its use and five (62.5%) did not support its use for treating mild COVID-19. The time to symptom resolution ranged from 8 to 10 days in the ivermectin-treated arms and on average 07 days in the atazanavir treatment. No serious adverse events related to the use of the two drugs were detected. Conclusion: evidence recommending the use of ivermectin dates back to the beginning of the pandemic period, 2020, but subsequently, with robust controlled clinical trials, new evidence does not support the use of ivermectin and atazanavir in the treatment of mild COVID-19 showing that there was no difference in time to symptom resolution, mortality rate, ICU admission rate, and length of hospital stay.


Objetivo: Examinar y mapear la evidencia científica sobre la eficacia del uso de ivermectina y atazanavir en el tratamiento de COVID-19. Metodología: Scoping Review, basada en los procedimientos recomendados por el Instituto Joanna Briggs. La pregunta guía era: "¿Cuál es la evidencia científica sobre el uso de ivermectina y atazanavir en el tratamiento de pacientes con síntomas leves de COVID-19? Se realizaron búsquedas en seis bases de datos nacionales e internacionales, en artículos publicados hasta diciembre de 2022. De los 357 estudios encontrados, se seleccionaron 22 para su lectura completa, lo que dio lugar a una muestra final de 11 estudios analizados. Resultados: Las 11 publicaciones analizadas fueron publicadas entre 2020 y 2022 durante el periodo pandémico, de ámbito nacional e internacional con diseño de estudio experimental, de tipo ensayo clínico con aleatorización. Apenas 03 estudios (25%) probaron el atazanavir como intervención combinada con otras drogas, sin evidenciar mejoras significativas en relación con su uso. En cuanto al tratamiento con Ivermectina, de los ocho (75%) estudios que la probaron, sólo tres (37,5%) recomendaron su uso y cinco (62,5%) no apoyaron su uso para tratar la COVID-19 leve. El tiempo transcurrido hasta la resolución de los síntomas osciló entre 8 y 10 días en los brazos tratados con ivermectina y una media de 07 días en el tratamiento con atazanavir. No se detectaron acontecimientos adversos graves relacionados con el uso de los dos fármacos. Conclusión: las pruebas que recomiendan el uso de ivermectina se remontan al inicio del periodo pandémico, 2020, pero posteriormente, con ensayos clínicos controlados sólidos, las nuevas pruebas no apoyan el uso de ivermectina y atazanavir en el tratamiento de la COVID-19 leve, lo que demuestra que no hubo diferencias en el tiempo hasta la resolución de los síntomas, la tasa de mortalidad, la tasa de ingreso en la UCI y la duración de la estancia hospitalaria.


Asunto(s)
Ivermectina/uso terapéutico , Sulfato de Atazanavir/uso terapéutico , COVID-19/tratamiento farmacológico , Antivirales , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/tratamiento farmacológico , Hospitalización
5.
Curr Issues Mol Biol ; 44(11): 5379-5389, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36354676

RESUMEN

Candida albicans is the chief etiological agent of candidiasis, a mycosis prevalent in individuals with acquired immunodeficiency syndrome (AIDS). In recent years, the introduction of human immunodeficiency virus (HIV) protease inhibitors (HIV-PI) has reduced the prevalence of candidiasis in these patients. Seeking new therapeutic strategies based on the perspective of drug repositioning, we evaluated the effects of two second-generation HIV-PIs, atazanavir (ATV) and darunavir (DRV), on virulence factors of C. albicans and experimental candidiasis. For this, clinical strains of C. albicans were subjected to in vitro and in vivo treatments with ATV or DRV. As a result, ATV and DRV exhibited antifungal activity against fungal cells at 512 µg/mL, reduced the viability and biomass of biofilms, and inhibited filamentation of C. albicans. In addition, these HIV-PIs downregulated the expression of SAP2 and BRC1 genes of C. albicans. In an in vivo study, prophylactic use of ATV and DRV prolonged the survival rate of Galleria mellonella larvae infected with C. albicans. Therefore, ATV and DRV showed activity against C. albicans by reducing cell growth, biofilm formation, filamentation, and expression of virulence genes. Furthermore, ATV and DRV decreased experimental candidiasis, suggesting the repurposing of HIV-PIs as antifungal treatments for C. albicans infections.

6.
Front Pharmacol ; 12: 660965, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34093191

RESUMEN

Background: Efavirenz (EFV), a non-nucleoside reverse transcriptase inhibitor, and atazanavir (ATV), a protease inhibitor, are drugs widely used in antiretroviral therapy (ART) for people living with HIV. These drugs have shown high interindividual variability in adverse drug reactions (ADRs). UGT1A1*28 and CYP2B6 c.516G>T have been proposed to be related with higher toxicity by ATV and EFV, respectively. Objective: To study the association between genetic polymorphisms and ADRs related to EFV or ATV in patients living with HIV treated at a public hospital in Chile. Methods: Epidemiologic, case-control, retrospective, observational study in 67 adult patients under EFV or ATV treatment was conducted, in the San Juan de Dios Hospital. Data were obtained from patients' medical records. Genotype analyses were performed using rtPCR for rs887829 (indirect identification of UGT1A1*28 allele) and rs3745274 (CYP2B6 c.516G>T), with TaqMan® probes. The association analyses were performed with univariate logistic regression between genetic variants using three inheritance models (codominant, recessive, and dominant). Results: In ATV-treated patients, hyperbilirubinemia (total bilirubin >1.2 mg/dl) had the main incidence (61.11%), and moderate and severe hyperbilirubinemia (total bilirubin >1.9 mg/dl) were statistically associated with UGT1A1*28 in recessive and codominant inheritance models (OR = 16.33, p = 0.028 and OR = 10.82, p = 0.036, respectively). On the other hand, in EFV-treated patients adverse reactions associated with CNS toxicity reached 34.21%. In this respect, nightmares showed significant association with CYP2B6 c.516G>T, in codominant and recessive inheritance models (OR = 12.00, p = 0.031 and OR = 7.14, p = 0.042, respectively). Grouped CNS ADRs (nightmares, insomnia, anxiety, and suicide attempt) also showed a statistically significant association with CYP2B6 c.516G > T in the codominant and recessive models (OR = 30.00, p = 0.011 and OR = 14.99, p = 0.021, respectively). Conclusion: Our findings suggest that after treatment with ATV or EFV, UGT1A1*28 and CYP2B6 c.516G>T influence the appearance of moderate-to-severe hyperbilirubinemia and CNS toxicity, respectively. However, larger prospective studies will be necessary to validate these associations in our population. Without a doubt, improving adherence in patients living with HIV is a critical issue to the success of therapy. Hence, validating and applying international pharmacogenetic recommendations in Latin American countries would improve the precision of ART: a fundamental aspect to achieve the 95-95-95 treatment target proposed by UNAIDS.

7.
Gac Med Mex ; 157(4): 384-390, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35133341

RESUMEN

INTRODUCTION: Antiretroviral treatment for HIV generates dyslipidemia, which is associated with cardiovascular risk and atherosclerosis. OBJECTIVE: To compare antiretroviral agents effects on lipids in patients with HIV-AIDS. METHODS: Retrospective cohort. The lipid profiles of patients receiving efavirenz (EFV) vs. atazanavir (ATV) with a zidovudine + lamivudine backbone for 36 months were compared. RESULTS: 212 patients were included in the study. From baseline to month 36, HDL increase in the group of patients treated with ATV was higher in comparison with that of patients on EFV (8.33 vs. 4.26; p < 0.01); a difference in triglycerides was observed between groups, with a decrease of 19.06 mg/dL in patients on ATV and an increase of 40.62 mg/dL in those who received EFV (p < 0.001). Mean difference in total and LDL-cholesterol change between both treatments was not significant (p = 0.32 and p = 0.951, respectively). CONCLUSIONS: ATV-containing regimens were associated with more favorable changes in triglyceride and HDL levels than EFV regimens. This benefit could be associated with a reduction in long-term cardiovascular risk; this relationship requires further study.


INTRODUCCIÓN: El tratamiento antirretroviral para VIH genera dislipidemia asociada a riesgo cardiovascular y aterosclerosis. OBJETIVO: Comparar los efectos lipídicos de los antirretrovirales en pacientes con VIH-sida. MÉTODOS: Cohorte retrospectiva. Se comparó el perfil lipídico de los pacientes que recibieron efavirenz (EFV) versus atazanavir (ATV) con una backbone de zidovudina + lamivudina durante 36 meses. RESULTADOS: Se incluyeron 212 pacientes. Desde el inicio hasta los 36 meses, el aumento del HDL del grupo de pacientes en tratamiento con ATV fue mayor en comparación con el que presentaron los pacientes con EFV (8.33 versus 4.26, respectivamente; p < 0.01); se observó una diferencia de triglicéridos entre los grupos, con disminución de 19.06 mg/dL en los pacientes con ATV y aumento de 40.62 mg/dL en los que recibieron EFV (p < 0.001). La diferencia de medias en el cambio de colesterol total y LDL entre ambos tratamientos no fue significativa (p = 0.32 y p = 0.951, respectivamente). CONCLUSIONES: Los regímenes con ATV se asociaron a cambios más favorables en los niveles de triglicéridos y HDL que los regímenes con EFV, relación que podría asociarse a reducción del riesgo cardiovascular a largo plazo, la cuál requiere estudios adicionales.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Alquinos , Fármacos Anti-VIH/efectos adversos , Sulfato de Atazanavir/uso terapéutico , Benzoxazinas , LDL-Colesterol , Estudios de Cohortes , Ciclopropanos , Infecciones por VIH/tratamiento farmacológico , Humanos , Estudios Retrospectivos
8.
Pharmaceuticals (Basel) ; 15(1)2021 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-35056078

RESUMEN

Atazanavir (ATV) has already been considered as a potential repurposing drug to 2019 coronavirus disease (COVID-19); however, there are controversial reports on its mechanism of action and effectiveness as anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Through the pre-clinical chain of experiments: enzymatic, molecular docking, cell-based and in vivo assays, it is demonstrated here that both SARS-CoV-2 B.1 lineage and variant of concern gamma are susceptible to this antiretroviral. Enzymatic assays and molecular docking calculations showed that SARS-CoV-2 main protease (Mpro) was inhibited by ATV, with Morrison's inhibitory constant (Ki) 1.5-fold higher than GC376 (a positive control) dependent of the catalytic water (H2Ocat) content. ATV was a competitive inhibitor, increasing the Mpro's Michaelis-Menten (Km) more than sixfold. Cell-based assays indicated that different lineages of SARS-CoV-2 is susceptible to ATV. Using oral administration of ATV in mice to reach plasmatic exposure similar to humans, transgenic mice expression in human angiotensin converting enzyme 2 (K18-hACE2) were partially protected against lethal challenge with SARS-CoV-2 gamma. Moreover, less cell death and inflammation were observed in the lung from infected and treated mice. Our studies may contribute to a better comprehension of the Mpro/ATV interaction, which could pave the way to the development of specific inhibitors of this viral protease.

9.
São José dos Campos; s.n; 2021. 53 p. tab.il., graf..
Tesis en Portugués | BBO - Odontología | ID: biblio-1281107

RESUMEN

Candida albicans é um fungo que habitualmente coloniza superfícies mucosas de humanos e pode assumir caráter patogênico a depender de fatores do hospedeiro. Portadores da Síndrome da Imunodeficiência Humana, causada pelo Vírus da Imunodeficiência Humana (HIV), são propícios a apresentar candidose nas mucosas devido a imunodeficiência celular que apresentam. A introdução da Terapia Antirretroviral (TARV), em especial o surgimento dos Inibidores da Protease do HIV (IPs-HIV), reduziu drasticamente a incidência e prevalência destas patologias ao longo dos anos. Estudos clínicos e epidemiológicos com IPs-HIV de primeira geração demostraram que tal redução não se deve exclusivamente à melhora imunológica promovida pela TARV, e pesquisas in vitro já demonstraram propriedades antifúngicas e antibiofilme de alguns IPs-HIV de primeiras gerações em C. albicans. Sendo assim, o objetivo deste estudo foi avaliar os efeitos do Atazanavir (ATV) e Darunavir (DRV), dois IPs-HIV de segunda e terceira geração respectivamente em uso clínico atual no Brasil, em diferentes fatores de virulência de C. albicans. Para isso foram realizados estudos com duas cepas clínicas de C. albicans isoladas de lesões de candidose orofaríngea de pacientes portadores de HIV para avaliar a ação in vitro das drogas na morfogênese, formação de biofilme (contagem de células viáveis e quantificação de biomassa) e na expressão dos genes de virulência BRC1 e SAP2, e in vivo no efeito protetor desses medicamentos na infecção experimental por C. albicans em modelo de Galleria mellonella. Os dados foram analisados por teste t, ANOVA, Kruskal-Wallis, Dunn e Kaplan-Meier (p<0,05). A Concentração Inibitória Mínima (CIM) para ambos os IPs-HIV testados foi 512 µg/mL. Nos biofilmes, a redução na contagem de UFC/mL de C. albicans nos grupos tratados com IPs-HIV foi de até 6,81 Log. A biomassa dos biofilmes tratados também sofreu reduções significantes para ATV (82%), DRV (81%) comparada ao grupo controle.DRV e ATV promoveram redução estatisticamente significante de expressão gênica de SAP2 e BRC1, respectivamente, quando comparados ao controle (p<0,05). Em relação à morfogênese de C. albicans, ATV e DRV inibiram significativamente a formação de hifas (p=0,0183). No estudo in vivo, o uso profilático de ATV e DRV em G. mellonella infectadas com C. albicans prolongou em até 40% a sobrevivência das larvas (p=0,0004). Conclui-se que ATV e DRV inibiram a filamentação e apresentaram atividade antifúngica, antibiofilme e na expressão de genes de fatores de virulência de C. albicans e preveniram candidose em G. mellonella(AU)


Candida albicans is a fungus that usually colonizes mucous surfaces of humans and can assume pathogenic character depending on host factors. Patients with Human Immunodeficiency Syndrome, caused by the Human Immunodeficiency Virus (HIV), are favorable to present mucous candidosis due to the cellular immunodeficiency they present. The introduction of Antiretroviral Therapy (ART), especially the emergence of HIV Protease Inhibitors (HIV-PI), has drastically reduced the incidence and prevalence of these mycosis over the years. Clinical and epidemiological studies with firstgeneration HIV-PIs have shown that this reduction is not exclusively due to the immunological improvement promoted by ART, and in vitro research has already demonstrated antifungal and antibiofilm properties of firsts-generations HIV-PIs on C. albicans. Thus, the aim of this study was to evaluate the effects of Atazanavir (ATV) and Darunavir (DRV), two HIV-PIs of second and third generation respectively currently in clinical use in Brazil, on virulence factors of C. albicans. For this purpose, studies were carried out with two clinical strains of C. albicans isolated from lesions of oropharyngeal candidosis of HIV positive patients to evaluate in vitro action of the drugs on morphogenesis, biofilm formation (number of viable cell and biomass determination) and virulence factor genes BRC1 and SAP2 expression and in vivo on the protective effect of these drugs on experimental infection by C. albicans in Galleria mellonella model. Data were analyzed by t Student, ANOVA, Kruskal-Wallis and Dunn and Kaplan-Meier (p<0.05) tests. The Minimum Inhibitory Concentration (MIC) for both tested HIV-PIs was 512 µg/mL. In biofilms, a reduction in the CFU/mL count of C. albicans in the groups treated with HIV-PIs was up to 6.81 log. The biomass of biofilms also suffered significant reductions for ATV (82%) and DRV (81%) compared to the control group. DRV and ATV statistically significantly downregulated the expression of SAP2 and BRC1 genes respectively (p<0,05). Regarding the morphogenesis of C. albicans, ATV and DRV inhibited the formation of hyphae (p = 0.0183). In the in vivo study, the prophylactic use of ATV and DRV in G. mellonella infected with C. albicans prolonged larval survival by up to 40% (p = 0.0004). We can conclude that ATV and DRV inhibited filamentation and showed antifungal activity, being able to inhibit growth, formation and virulence factors gene expression of C. albicans biofilm and prevented candidosis in G. mellonel(AU)


Asunto(s)
Candida albicans/inmunología , Inhibidores de la Proteasa del VIH/administración & dosificación , Factores de Virulencia/efectos adversos , Darunavir/síntesis química , Sulfato de Atazanavir/efectos adversos
10.
Antimicrob Agents Chemother ; 64(10)2020 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-32759267

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is already responsible for far more deaths than previous pathogenic coronaviruses (CoVs) from 2002 and 2012. The identification of clinically approved drugs to be repurposed to combat 2019 CoV disease (COVID-19) would allow the rapid implementation of potentially life-saving procedures. The major protease (Mpro) of SARS-CoV-2 is considered a promising target, based on previous results from related CoVs with lopinavir (LPV), an HIV protease inhibitor. However, limited evidence exists for other clinically approved antiretroviral protease inhibitors. Extensive use of atazanavir (ATV) as antiretroviral and previous evidence suggesting its bioavailability within the respiratory tract prompted us to study this molecule against SARS-CoV-2. Our results show that ATV docks in the active site of SARS-CoV-2 Mpro with greater strength than LPV, blocking Mpro activity. We confirmed that ATV inhibits SARS-CoV-2 replication, alone or in combination with ritonavir (RTV) in Vero cells and a human pulmonary epithelial cell line. ATV/RTV also impaired virus-induced enhancement of interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-α) levels. Together, our data strongly suggest that ATV and ATV/RTV should be considered among the candidate repurposed drugs undergoing clinical trials in the fight against COVID-19.


Asunto(s)
Antivirales/farmacología , Sulfato de Atazanavir/farmacología , Betacoronavirus/efectos de los fármacos , Citocinas/metabolismo , Ritonavir/farmacología , Animales , Sulfato de Atazanavir/química , Betacoronavirus/patogenicidad , Betacoronavirus/fisiología , COVID-19 , Muerte Celular/efectos de los fármacos , Chlorocebus aethiops , Proteasas 3C de Coronavirus , Infecciones por Coronavirus/tratamiento farmacológico , Infecciones por Coronavirus/metabolismo , Infecciones por Coronavirus/patología , Cisteína Endopeptidasas/química , Cisteína Endopeptidasas/metabolismo , Quimioterapia Combinada , Humanos , Inflamación/metabolismo , Inflamación/virología , Lopinavir/farmacología , Simulación del Acoplamiento Molecular , Monocitos/virología , Pandemias , Neumonía Viral/tratamiento farmacológico , Neumonía Viral/metabolismo , Neumonía Viral/patología , Inhibidores de Proteasas/farmacología , SARS-CoV-2 , Células Vero , Proteínas no Estructurales Virales/antagonistas & inhibidores , Proteínas no Estructurales Virales/química , Proteínas no Estructurales Virales/metabolismo , Replicación Viral/efectos de los fármacos , Tratamiento Farmacológico de COVID-19
11.
s.l; s.n; 4 maio 2020.
No convencional en Portugués | LILACS, BRISA/RedTESA | ID: biblio-1099482

RESUMEN

CONTEXTO: Esta foi uma revisão rápida desenvolvida durante a epidemia da COVID-19 no Brasil no intuito de informar cientificamente, e de modo imparcial, a tomada de decisão em saúde. OBJETIVOS: Identificar, avaliar sistematicamente e sumarizar as melhores evidências científicas disponíveis sobre a eficácia e a segurança do uso do atazanavir para COVID-19. MÉTODOS: Revisão sistemática rápida (rapid review methodology). RESULTADOS: Foram realizadas buscas sistemáticas nas principais bases de dados, as buscas foram realizadas no dia 13 de abril de 2020 e atualizadas no dia 28 de abril de 2020. Após o processo de seleção, não foi identificado nenhum estudo clínico realizado com o atazanavir para o tratamento de pacientes com COVID-19. Também não há estudos em andamento. Os estudos disponíveis foram realizados in vitro e apresentam resultados contraditórios. Em um dos estudos os autores relataram que não foi observada atividade antiviral do atazanavir contra a SARS CoV-2. Em outro estudo, o atazanavir sozinho e associado ao ritonavir apresentou inibição da replicação viral de SARS-CoV-2 em diferentes linhagens celulares, e a associação de ritonavir ao atazanavir demostrou ser ainda mais potente na inibição da replicação de SARS-CoV-2 comparado com atazanavir sozinho e com cloroquina. A ação inibitória de atazanavir isolado e associado ao ritonavir também foi comprovada em células epiteliais pulmonares humanas. CONCLUSÃO: Apesar dos resultados divergentes dos estudos in vitro, o atazanavir é um medicamento em potencial a ser avaliado em ensaios clínicos quanto a eficácia no tratamento da COVID-19. Até o momento, o uso de atazanavir no tratamento da COVID-19 permanece não comprovado e depende de testes clínicos para que haja avanço no reconhecimento de sua eficácia.(AU)


Asunto(s)
Humanos , Neumonía Viral/tratamiento farmacológico , Infecciones por Coronavirus/tratamiento farmacológico , Sulfato de Atazanavir/uso terapéutico , Betacoronavirus/efectos de los fármacos , Evaluación de la Tecnología Biomédica , Análisis Costo-Beneficio
12.
Int Immunopharmacol ; 60: 179-188, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29747123

RESUMEN

HIV aspartyl protease inhibitors are able to modulate multiple defense mechanisms. However, their influence on the immune response against Leishmania has rarely been investigated. The aim of our study was to investigate whether in vivo treatment with HIV aspartyl protease inhibitors is able to modulate the immune response during Leishmania infection. Using Leishmania (L.) amazonensis-infected mice, we analyzed the disease evolution and parasite load, immunophenotypic profiles of splenic T and B lymphocytes, numbers of lymphoid aggregates in the spleen, percentages of circulating atypical lymphocytes and reactive monocytes, and serum levels of cytokines and nitric oxide (NO) after 30 days of oral treatment with lopinavir/ritonavir (LPV/RTV) or atazanavir (ATV). We observed that LPV/RTV and ATV did not modify the disease evolution or parasite load. However, the antiretroviral treatment induced an increase in activated lymphocytes in the spleen and blood, as well as a decrease in CD69 expression in T and B lymphocytes in the spleen. The treatment also resulted in an increase in activated monocytes in the blood. In addition, antiretrovirals decreased levels of IL-17A and increased levels of NO in sera from Leishmania-infected mice. Thus, our results demonstrate for the first time that in vivo treatment with HIV aspartyl protease inhibitors modifies innate and adaptative immune responses during Leishmania infection and suggest that these drugs could change the clinical course of leishmaniasis in HIV infected-individuals.


Asunto(s)
Inhibidores de la Proteasa del VIH/farmacología , Inhibidores de la Proteasa del VIH/uso terapéutico , Leishmaniasis/tratamiento farmacológico , Animales , Sulfato de Atazanavir/farmacología , Sulfato de Atazanavir/uso terapéutico , Citocinas/sangre , Femenino , Leishmaniasis/sangre , Leishmaniasis/parasitología , Recuento de Leucocitos , Leucocitos/efectos de los fármacos , Lopinavir/farmacología , Lopinavir/uso terapéutico , Ratones Endogámicos BALB C , Óxido Nítrico/sangre , Ritonavir/farmacología , Ritonavir/uso terapéutico , Piel/efectos de los fármacos , Piel/parasitología , Bazo/efectos de los fármacos , Bazo/inmunología , Bazo/parasitología
13.
RECIIS (Online) ; 10(1): 1-21, jan.-mar.2016. ilus, graf
Artículo en Portugués | LILACS | ID: lil-784669

RESUMEN

O alto custo dos medicamentos antirretrovirais (ARVs) justifica estudos sobre estratégias de patenteamento farmacêutico vis-à-vis à política pública brasileira de acesso universal aos ARVs. A análise da evolução das tendências tecnológicas através do estudo de patentes fornece também uma visão dos envolvidos no desenvolvimento de uma tecnologia. Para traçar o perfil de patenteamento do antirretroviral atazanavir, no Brasil e no mundo, foi realizado um estudo na base de dados Thomson Reuters Integrity que identificou o desenvolvimento, produção e comercialização desse produto. Foram identificados 49 documentos de patentes, tendo a proteção dessa tecnologia se iniciado em 1996, com a empresa Novartis e seu licenciado,a Bristol, que reivindicaram proteção para a molécula. Prossegue até 2013, com proteção de invenções incrementais, originárias na China. O estudo possibilitou discutir a importância do sistema de patentes na promoção da inovação, e evidenciar tipos diversos de proteção para um produto e tecnologias relacionadas...


The high costs of antiretroviral drugs (ARVs) justifies studies on pharmaceutical patenting strategiesvis-à-vis the Brazilian public policy of universal access to ARVs. The analysis of the evolution oftechnology trends through patent study also provides an overview of those involved in the developmentof a technology. To trace the patenting profile of atazanavir antiretroviral in Brazil and in the world,a study was conducted using Thomson Reuters Integrity database and such study identified thedevelopment, production and marketing of this product. 49 patent documents were identified, havingbeen started the protection of this technology in 1996 with Novartis and its licensee Bristol, whichclaimed protection for the molecule. It remains until 2013, with protection of incremental inventionsoriginating in China. The study has allowed to discuss the importance of the patent system to promotinginnovation, and to highlight different types of protection for a product and related technologies...


El alto costo de los medicamentos antirretrovirales (ARVs) justifica estudios sobre estrategias de protecciónde patentes farmacéuticas vis-à-vis la política brasileña de acceso universal a los ARVs. El análisis de laevolución de las tendencias tecnológicas a través del estudio de las patentes posibilita una visión de losdiferentes actores responsables por el desarrollo de la tecnologia. Para analizar el perfil de patentamientodel antirretroviral atazanavir en Brasil y en el mundo se realizó un estudio através de la base de datosde Thomson Reuters Integrity a fin de identificar el desarrollo, la producción y comercialización delproducto. Fueron identificados 49 documentos de patentes y los resultados muestran que la protección dela tecnologia comienza en 1996 con Novartis y el detentor de su licencia, Bristol, las cuales reivindicaronprotección para la molécula. que continúa hasta 2013, con documentos originarios de China, que provienende invenciones incrementales. El estudio posibilitó discutir la importancia del sistema de patentes parafomentar la innovación y permitir diferentes tipos de protección para un producto y tecnologias relacionadas...


Asunto(s)
Humanos , Terapia Antirretroviral Altamente Activa , Costos de los Medicamentos , Propiedad Intelectual , Industria Farmacéutica/economía , Patentes como Asunto/legislación & jurisprudencia , Terapia Antirretroviral Altamente Activa/economía , Bases de Datos como Asunto , Propiedad Intelectual de Productos y Procesos Farmacéuticos , Política Nacional de Medicamentos , Derecho a la Salud
14.
Clin Infect Dis ; 58(4): 555-63, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24253247

RESUMEN

BACKGROUND: We aimed to evaluate treatment responses to atazanavir plus ritonavir (ATV/r) or efavirenz (EFV) in initial antiretroviral regimens among women and men, and determine if treatment outcomes differ by sex. METHODS: We performed a randomized trial of open-label ATV/r or EFV combined with abacavir/lamivudine (ABC/3TC) or tenofovir/emtricitabine (TDF/FTC) in 1857 human immunodeficiency virus type 1-infected, treatment-naive persons enrolled between September 2005 and November 2007 at 59 sites in the United States and Puerto Rico. Associations of sex with 3 primary study endpoints of time to virologic failure, safety, and tolerability events were analyzed using Cox proportional hazards models. Model-based population pharmacokinetic analysis was performed using nonlinear mixed effects modeling (NONMEM version VII). RESULTS: Of 1857 participants, 322 were women. Women assigned to ATV/r had a higher risk of virologic failure with either nucleoside reverse transcriptase inhibitor backbone than women assigned to EFV, or men assigned to ATV/r. The effects of ATV/r and EFV upon safety and tolerability risk did not differ significantly by sex. With ABC/3TC, women had a significantly higher (32%) safety risk compared to men; with TDF/FTC, the safety risk was 20% larger for women compared to men, but not statistically significant. Women had slower ATV clearance and higher predose levels of ATV compared to men. Self-reported adherence did not differ significantly by sex. CONCLUSIONS: This is the first randomized clinical trial to identify a significantly earlier time to virologic failure in women randomized to ATV/r compared to women randomized to EFV. This finding has important clinical implications given that boosted protease inhibitors are often favored over EFV in women of childbearing potential. CLINICAL TRIALS REGISTRATION: NCT00118898.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Terapia Antirretroviral Altamente Activa/métodos , Infecciones por VIH/tratamiento farmacológico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Fármacos Anti-VIH/efectos adversos , Terapia Antirretroviral Altamente Activa/efectos adversos , Femenino , Infecciones por VIH/virología , VIH-1/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Puerto Rico , Factores Sexuales , Resultado del Tratamiento , Estados Unidos , Adulto Joven
15.
Braz. j. infect. dis ; Braz. j. infect. dis;17(6): 657-660, Nov.-Dec. 2013. tab
Artículo en Inglés | LILACS | ID: lil-696966

RESUMEN

OBJECTIVE: To evaluate the factors associated with plasma concentrations of atazanavir (ATV) in a cohort of well-controlled HIV infected subjects (undetectable viremia). Design: Cross-sectional study where 69 subjects were consecutively enrolled between April and November, 2011. METHODS: Patients had to be on atazanavir for at least six months, undetectable viral load for a period equal to or longer than 12 months, T CD4+ lymphocyte count higher than 200 cells/mm³, and aged between 18 years and 70 years old. Exclusion criteria were pregnancy, any neurologic disease, active opportunistic disease, hepatitis or cancer. Atazanavir plasma levels were measured by ultra-performance liquid chromatography. RESULTS AND DISCUSSION: Overall, 54 patients (mean age of 47 years and 50% women) were included in the analysis. Those without ritonavir (unboosted atazanavir) had statistically lower plasma concentrations than those with ritonavir boosted atazanavir (p = 0.001) and total and indirect bilirubin were statistically associated with plasma concentration of atazanavir (r = 0.32 and r = 0.33 respectively; p < 0.05 in both cases). no statistical association was found among gender, ethnicity, age, weight, body mass index (BMI), lipid profile, and the plasma concentration of atazanavir. CONCLUSION: in summary, as expected, concomitant ritonavir use was the only factor associated with atazanavir plasma levels. prospective studies with a larger sample size might help to observe an association of atazanavir concentrations to other characteristics such as body weight, since the p-value showed to be close to significance (p = 0.068).


Asunto(s)
Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Fármacos Anti-VIH/sangre , Infecciones por VIH/sangre , Oligopéptidos/sangre , Piridinas/sangre , Fármacos Anti-VIH/farmacocinética , Fármacos Anti-VIH/uso terapéutico , Cromatografía Liquida , Estudios de Cohortes , Estudios Transversales , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , Oligopéptidos/farmacocinética , Oligopéptidos/uso terapéutico , Estudios Prospectivos , Piridinas/farmacocinética , Piridinas/uso terapéutico , Carga Viral
16.
Braz J Infect Dis ; 17(6): 657-60, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23933406

RESUMEN

OBJECTIVE: To evaluate the factors associated with plasma concentrations of atazanavir (ATV) in a cohort of well-controlled HIV infected subjects (undetectable viremia). DESIGN: Cross-sectional study where 69 subjects were consecutively enrolled between April and November, 2011. METHODS: Patients had to be on atazanavir for at least six months, undetectable viral load for a period equal to or longer than 12 months, T CD4+ lymphocyte count higher than 200 cells/mm(3), and aged between 18 years and 70 years old. Exclusion criteria were pregnancy, any neurologic disease, active opportunistic disease, hepatitis or cancer. Atazanavir plasma levels were measured by ultra-performance liquid chromatography. RESULTS AND DISCUSSION: Overall, 54 patients (mean age of 47 years and 50% women) were included in the analysis. Those without ritonavir (unboosted atazanavir) had statistically lower plasma concentrations than those with ritonavir boosted atazanavir (p=0.001) and total and indirect bilirubin were statistically associated with plasma concentration of atazanavir (r=0.32 and r=0.33 respectively; p<0.05 in both cases). No statistical association was found among gender, ethnicity, age, weight, body mass index (BMI), lipid profile, and the plasma concentration of atazanavir. CONCLUSION: In summary, as expected, concomitant ritonavir use was the only factor associated with atazanavir plasma levels. Prospective studies with a larger sample size might help to observe an association of atazanavir concentrations to other characteristics such as body weight, since the p-value showed to be close to significance (p=0.068).


Asunto(s)
Fármacos Anti-VIH/sangre , Infecciones por VIH/sangre , Oligopéptidos/sangre , Piridinas/sangre , Adolescente , Adulto , Anciano , Fármacos Anti-VIH/farmacocinética , Fármacos Anti-VIH/uso terapéutico , Sulfato de Atazanavir , Recuento de Linfocito CD4 , Cromatografía Liquida , Estudios de Cohortes , Estudios Transversales , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , Humanos , Masculino , Persona de Mediana Edad , Oligopéptidos/farmacocinética , Oligopéptidos/uso terapéutico , Estudios Prospectivos , Piridinas/farmacocinética , Piridinas/uso terapéutico , Carga Viral , Adulto Joven
17.
AIDS care ; 22(6): 677-686, June 2010.
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IIERPROD, Sec. Est. Saúde SP | ID: biblio-1059245

Asunto(s)
VIH-1
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