RESUMO
A bioanalytical method for the determination of lumefantrine and its metabolite desbutyl-lumefantrine in plasma samples using microextraction by packed sorbent (MEPS) and high-performance liquid chromatography was developed and validated. A complete factorial planning and surface response approach were employed to optimize the extraction parameters sample volume, dilution, aspirated sample volume and extraction cycles. The method employed C18 MEPS sorbent and diazepam as internal standard (IS). Separation was performed on a Luna C18 column (250 mm × 4.6 mm, 5 µm) at 35 °C, with mobile phase composed of acetonitrile and 0.05 % trifluoroacetic acid (68:32, v/v), detection at 305 nm and injection volume of 25 µL. The developed method showed to be selective, precise, accurate and linear in the range of 50-5000 ng/mL for lumefantrine and desbutyl-lumefantrine. Using the optimized MEPS procedure, high recovery rates were obtained for both analytes and IS (92.2 %-99.0 %). The method was successfully applied for the determination of lumefantrine and its metabolite in human plasma samples after oral administration of lumefantrine tablets in healthy volunteers.
Assuntos
Cromatografia Líquida de Alta Pressão , Lumefantrina , Microextração em Fase Sólida , Humanos , Limite de Detecção , Lumefantrina/sangue , Reprodutibilidade dos TestesRESUMO
Introduction: In Colombia, the published studies for the treatment of uncomplicated Plasmodium falciparum malaria with Artemether-Lumefantrine are scarce. The aim of the study was to evaluate the therapeutic efficacy and safety profile of this combination. Methods: A clinical trial was performed in adults with uncomplicated P. falciparum malaria using the 28‑day World Health Organization validated protocol. Patients received supervised antimalarial treatment and the primary efficacy endpoint was the clinical and parasitological response. Safety was assessed through adverse events surveillance and plasmatic levels of antimalarial drugs were measured. Results: 88 patients were included. Adequate clinical and parasitological response rate of 100% on day 28 was achieved in 84 patients, diagnosed by thick blood smear examination. There were four parasitological therapeutic failures (5%) detected by polymerase chain reaction. Discusion: Therapeutic efficacy similar to previous studies was established with a slight increase in therapeutic failure. The serum levels of the antimalarials were adequate and the few cases of therapeutic failure were not related. Conclusion: Treatment of uncomplicated P. falciparum malaria with Artemeter-Lumefantrine was effective and safe in the study population. All patients reached adequate plasma concentrations of the drugs; therapeutic failures were not associated with low blood levels of the drug clinical trial.
Introducción: Son escasos los estudios en Colombia sobre eficacia del tratamiento para Plasmodium falciparum con la combinación Artemeter-Lumefantrina. El objetivo de este estudio fue evaluar la eficacia terapéutica y el perfil de seguridad de este tratamiento combinado. Métodos: Se realizó un ensayo clínico en adultos con malaria por P. falciparum no complicada, utilizando el esquema de 28 días recomendado por la Organización Mundial de la Salud (OMS). Los pacientes recibieron el tratamiento supervisado y el desenlace primario evaluado fue la respuesta clínica y parasitológica. La seguridad fue evaluada a través de vigilancia de efectos adversos y medición de niveles plasmáticos del medicamento. Resultados: Se incluyeron 88 pacientes. La tasa de curación clínica y parasitológica fue del 100% en 84 pacientes que tuvieron examen de gota gruesa al día 28. Hubo cuatro (5%) fallas parasitológicas detectada por reacción en cadena de polimerasa. Discusión: La eficacia terapéutica fue similar a la reportada en estudios previos con un ligero aumento de falla terapéutica. Los niveles plasmáticos de los antimalaricos fueron adecuados y no relacionados con la falla terapéutica. Conclusión: El tratamiento de malaria por P. falciparum no complicada con Artemeter-Lumefantrina fue efectiva y segura en la población estudiada. Todos los pacientes alcanzaron niveles en plasma adecuados y no se encontró asociación de falla terapéutica con bajos niveles en sangre.
Assuntos
Humanos , Masculino , Adulto , Plasmodium falciparum , Malária , Organização Mundial da Saúde , Ensaio Clínico , Malária Falciparum , Colômbia , Artemeter , LumefantrinaRESUMO
Background: Colombia began using artemisinin-based combination therapies for the treatment of uncomplicated Plasmodium falciparum malaria in 2006. It is necessary to implement resistance surveillance to antimalarial drugs in order to promptly detect changes in parasite susceptibility. The aim of this study was to establish a susceptibility baseline of P. falciparum to artemether-lumefantrine using three monitoring tools. Methods: Patients with uncomplicated malaria treated with artemether-lumefantrine underwent clinical and parasitological follow-up over 28 days. Ex vivo test was performed using the microtest technique for chloroquine, arthemeter, dihydroartemisinin and lumefantrine. Pfmdr1 copy number and polymorphisms in Pfk13, Pfatp6, Pfcrt and Pfmdr1 genes were analyzed. Results: From a total of 150 screened patients, 49 completed follow-up for 28 days. All treated patients had adequate clinical and parasitological responses. Parasitic clearance showed a drastic reduction of parasite biomass at 24 hours and complete elimination at 48 hours. One hundred eleven isolates were processed, all exhibited high susceptibility to artemisinins and a slight decrease in susceptibility to lumefantrine. No genetic polymorphisms associated with resistance to artemisinin were found. Conclusion: This study generated a susceptibility baseline in response to therapy with Coartem (artemether-lumefantrine) with numerical reference values, which will allow data comparison with future studies to systematically monitor changes in the parasite and to provide an early alert to the health authorities.
Assuntos
Antimaláricos/uso terapêutico , Artemisininas/uso terapêutico , Etanolaminas/uso terapêutico , Fluorenos/uso terapêutico , Malária/tratamento farmacológico , Plasmodium falciparum/efeitos dos fármacos , Adolescente , Adulto , Idoso , Antimaláricos/farmacologia , Artemeter , Combinação Arteméter e Lumefantrina , Artemisininas/farmacologia , Criança , Colômbia , Variações do Número de Cópias de DNA , Combinação de Medicamentos , Resistência a Medicamentos/efeitos dos fármacos , Resistência a Medicamentos/genética , Quimioterapia Combinada , Etanolaminas/farmacologia , Feminino , Fluorenos/farmacologia , Humanos , Lumefantrina , Malária/parasitologia , Masculino , Pessoa de Meia-Idade , Parasitemia/tratamento farmacológico , Plasmodium falciparum/isolamento & purificação , Polimorfismo Genético , Proteínas de Protozoários/genética , Adulto JovemRESUMO
Lumefantrine (LF) is an aryl-amino alcohol antimalarial drug used in artemisinin-based combination therapies against malaria worldwide. In this study, we investigated the genotoxic effects of LF in human lymphocytes in vitro, and the potential noncovalent interaction of LF with DNA using a 3D DNA-docking model. The number of DNA breaks and the frequency of nuclear buds (NBUDS) was significantly increased (P < 0.01 and P < 0. 05, respectively) at LF concentrations of 60, 80, and 100 µg/mL (LF60, LF80, and LF100, respectively). Frequency () of micronuclei (MN) formation also increased after LF treatments. However, this was only significant for LF100 (P = 0.01) and LF80 (P = 0.001). LF did not affect the frequency of nucleoplasmic bridges (NPBs) (P = 0.12) or the nuclear division index (NDI) (P = 0.32). Computational analysis suggests that LF may interact noncovalently with DNA via the DNA minor groove surface with a predicted binding affinity energy of -7.2 kcal/mol and showing a favorable shape complementary to this groove. Our results suggest that LF has clastogenic effects in human lymphocytes in vitro due to noncovalent interaction with the minor groove of DNA.
Assuntos
DNA/metabolismo , Etanolaminas/química , Etanolaminas/toxicidade , Fluorenos/química , Fluorenos/toxicidade , Linfócitos/efeitos dos fármacos , Adulto , Antimaláricos/química , Antimaláricos/toxicidade , Células Cultivadas , Ensaio Cometa , DNA/química , Etanolaminas/metabolismo , Feminino , Fluorenos/metabolismo , Humanos , Lumefantrina , Masculino , Testes para Micronúcleos , Simulação de Acoplamento MolecularRESUMO
In 2008, artemether-lumefantrine was introduced in Guinea-Bissau, West Africa, but quinine has also been commonly prescribed for the treatment of uncomplicated Plasmodium falciparum malaria. An efficacious high-dose chloroquine treatment regimen was used previously. Temporal and seasonal changes of genetic polymorphisms associated with altered drug susceptibility to chloroquine, lumefantrine, and quinine have been described. P. falciparum chloroquine resistance transporter (pfcrt) K76T, pfmdr1 gene copy numbers, pfmdr1 polymorphisms N86Y and Y184F, and pfmdr1 sequences 1034 to 1246 were determined using PCR-based methods. Blood samples came from virtually all (n=1,806) children<15 years of age who had uncomplicated P. falciparum monoinfection and presented at a health center in suburban Bissau (from 2003 to 2012). The pfcrt K76T and pfmdr1 N86Y frequencies were stable, and seasonal changes were not seen from 2003 to 2007. Since 2007, the mean annual frequencies increased (P<0.001) for pfcrt 76T (24% to 57%), pfmdr1 N86 (72% to 83%), and pfcrt 76+pfmdr1 86 TN (10% to 27%), and pfcrt 76T accumulated during the high transmission season (P=0.001). The pfmdr1 86+184 NF frequency increased from 39% to 66% (from 2003 to 2011; P=0.004). One sample had two pfmdr1 gene copies. pfcrt 76T was associated with a lower parasite density (P<0.001). Following the discontinuation of an effective chloroquine regimen, probably highly artemether-lumefantrine-susceptible P. falciparum (with pfcrt 76T) accumulated, possibly due to suboptimal use of quinine and despite a fitness cost linked to pfcrt 76T. (The studies reported here were registered at ClinicalTrials.gov under registration no. NCT00137514 [PSB-2001-chl-amo], NCT00137566 [PSB-2004-paracetamol], NCT00426439 [PSB-2006-coartem], NCT01157689 [AL-eff 2010], and NCT01704508 [Eurartesim 2012].).
Assuntos
Antimaláricos/uso terapêutico , Cloroquina/uso terapêutico , Etanolaminas/uso terapêutico , Fluorenos/uso terapêutico , Quinina/uso terapêutico , Adolescente , Antimaláricos/efeitos adversos , Criança , Pré-Escolar , Cloroquina/efeitos adversos , Etanolaminas/efeitos adversos , Feminino , Fluorenos/efeitos adversos , Guiné-Bissau , Humanos , Lumefantrina , Malária Falciparum/tratamento farmacológico , Masculino , Quinina/efeitos adversosRESUMO
INTRODUCTION: In Colombia, there are no published studies for the treatment of uncomplicated Plasmodium falciparum malaria comparing artemisinin combination therapies. Hence, it is intended to demonstrate the non-inferior efficacy/safety profiles of artesunate + amodiaquine versus artemether-lumefantrine treatments. METHODS: A randomized, controlled, open-label, noninferiority (Δ≤5%) clinical trial was performed in adults with uncomplicated P. falciparum malaria using the 28-day World Health Organization validated design/definitions. Patients were randomized 1:1 to either oral artesunate + amodiaquine or artemether-lumefantrine. The primary efficacy endpoint: adequate clinical and parasitological response; secondary endpoints: - treatment failures defined per the World Health Organization. SAFETY: assessed through adverse events. RESULTS: A total of 105 patients was included in each group: zero censored observations. Mean (95%CI - Confidence interval) adequate clinical and parasitological response rates: 100% for artesunate + amodiaquine and 99% for artemether-lumefantrine; the noninferiority criteria was met (Δ=1.7%). There was one late parasitological therapeutic failure (1%; artemether-lumefantrine group), typified by polymerase chain reaction as the MAD20 MSP1 allele. The fever clearance time (artesunate + amodiaquine group) was significantly shorter (p=0.002). Respectively, abdominal pain for artesunate + amodiaquine and artemether-lumefantrine was 1.9% and 3.8% at baseline (p=0.68) and 1% and 13.3% after treatment (p<0.001). CONCLUSIONS: Uncomplicated P. falciparum malaria treatment with artesunate + amodiaquine is noninferior to the artemether-lumefantrine standard treatment. The efficacy/safety profiles grant further studies in this and similar populations.
Assuntos
Amodiaquina/administração & dosagem , Antimaláricos/administração & dosagem , Artemisininas/administração & dosagem , Etanolaminas/administração & dosagem , Fluorenos/administração & dosagem , Malária Falciparum/tratamento farmacológico , Adulto , Amodiaquina/efeitos adversos , Antimaláricos/efeitos adversos , Artemeter , Artemisininas/efeitos adversos , Colômbia , Combinação de Medicamentos , Quimioterapia Combinada/métodos , Etanolaminas/efeitos adversos , Feminino , Fluorenos/efeitos adversos , Humanos , Lumefantrina , Masculino , Resultado do TratamentoRESUMO
A liquid chromatography-electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) method for the simultaneous quantitation of artemether and lumefantrine in human plasma was developed and validated. Artesunate was used as an internal standard (IS). The analytes were extracted by a protein precipitation procedure and separated on a reversed-phase Zorbax SB-Ciano column with a mobile phase composed of methanol and 10mM aqueous ammonium acetate containing 0.2% (v/v) acetic acid and 0.1% (v/v) formic acid. Multiple reaction monitoring was performed using the transitions m/z 316 â m/z 267, m/z 530 â m/z 348 and m/z 402 â m/z 267 to quantify artemether, lumefantrine and artesunate, respectively. Calibration curves were constructed over the range of 10-1000 ng/mL for artemether and 10-18,000 ng/mL for lumefantrine. The lower limit of quantitation was 10 ng/mL for both drugs. The mean R.S.D. values for the intra-run precision were 2.6% and 3.0% and for the inter-run precision were 3.6% and 4.6% for artemether and lumefantrine, respectively. The mean accuracy values were 102.0% and 101.2% for artemether and lumefantrine, respectively. No matrix effect was detected in the samples. The validated method was successfully applied to determine the plasma concentrations of artemether and lumefantrine in healthy volunteers, in a one-dose pharmacokinetic study, over the course of 11 days.
Assuntos
Antimaláricos/análise , Artemisininas/análise , Cromatografia Líquida/métodos , Etanolaminas/análise , Fluorenos/análise , Espectrometria de Massas em Tandem/métodos , Acetatos/química , Ácido Acético/química , Antimaláricos/farmacocinética , Artemeter , Artemisininas/farmacocinética , Calibragem , Etanolaminas/farmacocinética , Fluorenos/farmacocinética , Formiatos/química , Humanos , Lumefantrina , Metanol/química , Modelos Químicos , Controle de Qualidade , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray/métodosRESUMO
This paper describes the development and validation of a HPLC-UV method (210 nm) for the simultaneous quantitation of artemether and lumefantrine in fixed dose combination tablets. The method showed to be linear (r(2)>0.99), precise (R.S.D.<2.0%), accurate (recovery of 101.07% for artemether and 101.58% for lumefantrine), specific and robust. Four batches of artemether-lumefantrine tablets were assayed by the validated method. The artemether contents in the tablets varied from 98.61% to 103.35%, while lumefantrine contents were 97.92-100.48%.
Assuntos
Antimaláricos/análise , Artemisininas/análise , Cromatografia Líquida de Alta Pressão/métodos , Etanolaminas/análise , Fluorenos/análise , Espectrofotometria Ultravioleta/métodos , Antimaláricos/química , Artemeter , Artemisininas/química , Formas de Dosagem , Combinação de Medicamentos , Etanolaminas/química , Fluorenos/química , Lumefantrina , Estrutura Molecular , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Comprimidos/análiseRESUMO
This paper describes the development and evaluation of a HPLC, UV spectrophotometry and potentiometric titration methods to quantify lumefantrine in raw materials and tablets. HPLC analyses were carried out using a Symmetry C(18) column and a mobile phase composed of methanol and 0.05% trifluoroacetic acid (80:20), with a flow rate of 1.0ml/min and UV detection at 335nm. For the spectrophotometric analyses, methanol was used as solvent and the wavelength of 335nm was selected for the detection. Non-aqueous titration of lumefantrine was carried out using perchloric acid as titrant and glacial acetic acid/acetic anhydride as solvent. The end point was potentiometrically determined. The three evaluated methods showed to be adequate to quantify lumefantrine in raw materials, while HPLC and UV methods presented the most reliable results for the analyses of tablets.
Assuntos
Antimaláricos/análise , Cromatografia Líquida de Alta Pressão/métodos , Etanolaminas/análise , Fluorenos/análise , Preparações Farmacêuticas/análise , Espectrofotometria Ultravioleta/métodos , Titulometria/métodos , Antimaláricos/química , Etanolaminas/química , Fluorenos/química , Lumefantrina , Estrutura Molecular , Preparações Farmacêuticas/química , Padrões de Referência , Reprodutibilidade dos Testes , Comprimidos , Fatores de TempoRESUMO
This randomized, open-label study compared a three-day, six-dose regimen of artemether-lumefantrine with a five-day, 19-dose regimen of quinine-doxycycline for the treatment of Plasmodium falciparum malaria in the western Amazon region of Brazil. All patients remained hospitalized during their treatment and the study assessments were scheduled daily from the start of treatment (day 0) through day 6. By day 3, the percentage of infected patients was 0% in the artemether-lumefantrine group and 48.8% in the quinine-doxycycline group. Median parasite clearance time was significantly shorter in the artemether-lumefantrine group (two days) compared with the quinine-doxycycline group (three days) (P < 0.0001). Two patients in the quinine-doxycycline group left the study early because of treatment ineffectiveness or adverse event. Adverse events were reported by 91.5% of the study participants, most of which were mild in severity and/or not considered related to study treatment. Artemether-lumefantrine was shown to be an efficacious, safe, and convenient treatment for P. falciparum malaria in a highly drug-resistant region of South America.