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1.
Leuk Lymphoma ; 58(5): 1094-1104, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-27659997

RESUMEN

Using SEER-Medicare linked data we identified elderly patients diagnosed with diffuse large B-cell lymphoma (DLBCL) between January 2000 and December 2007 who received second-line outpatient chemotherapy for relapsed or refractory disease. Second-line regimens were classified into three mutually exclusive groups: aggressive, conventional, and palliative. Of the 632 (426 relapsed, 206 refractory) patients in the cohort, 27.8% received aggressive second-line therapy, 39.1% received conventional therapy, and 33.1% received palliative therapy. There were no differences in survival by type of therapy received, either for relapsed or refractory patients, although the patient risk profile differed significantly. However, duration of remission, male gender, and anemia at diagnosis were important predictors in relapsed patients, and male gender, B-symptoms, comorbidity burden, and poverty status were important predictors in refractory patients. Survival in elderly patients receiving second-line therapy remains poor, and the 24-month cost of all care exceeds $97,000. Patients would benefit from improved treatment options.


Asunto(s)
Atención Ambulatoria , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Linfoma de Células B Grandes Difuso/epidemiología , Factores de Edad , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Comorbilidad , Resistencia a Antineoplásicos , Femenino , Costos de la Atención en Salud , Humanos , Estimación de Kaplan-Meier , Linfoma de Células B Grandes Difuso/diagnóstico , Masculino , Estadificación de Neoplasias , Pautas de la Práctica en Medicina , Pronóstico , Modelos de Riesgos Proporcionales , Recurrencia , Retratamiento , Programa de VERF , Resultado del Tratamiento
2.
J Comp Eff Res ; 4(1): 37-50, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25565068

RESUMEN

AIMS: To examine the impact of research design on results in two published comparative effectiveness studies. METHODS: Guidelines for comparative effectiveness research have recommended incorporating disease process in study design. Based on the recommendations, we develop a checklist of considerations and apply the checklist in review of two published studies on comparative effectiveness of colony-stimulating factors. Both studies used similar administrative claims data, but different methods, which resulted in directionally different estimates. RESULTS: Major design differences between the two studies include: whether the timing of intervention in disease process was identified and whether study cohort and outcome assessment period were defined based on this temporal relationship. CONCLUSION: Disease process and timing of intervention should be incorporated into the design of comparative effectiveness studies.


Asunto(s)
Factores Estimulantes de Colonias/uso terapéutico , Investigación sobre la Eficacia Comparativa , Neutropenia Febril/prevención & control , Neoplasias/tratamiento farmacológico , Proyectos de Investigación , Lista de Verificación , Neutropenia Febril/etiología , Humanos , Neoplasias/complicaciones
3.
BMC Health Serv Res ; 13: 60, 2013 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-23406481

RESUMEN

BACKGROUND: Healthcare claims databases have been used in several studies to characterize the risk and burden of chemotherapy-induced febrile neutropenia (FN) and effectiveness of colony-stimulating factors against FN. The accuracy of methods previously used to identify FN in such databases has not been formally evaluated. METHODS: Data comprised linked electronic medical records from Geisinger Health System and healthcare claims data from Geisinger Health Plan. Subjects were classified into subgroups based on whether or not they were hospitalized for FN per the presumptive "gold standard" (ANC <1.0×10(9)/L, and body temperature ≥38.3°C or receipt of antibiotics) and claims-based definition (diagnosis codes for neutropenia, fever, and/or infection). Accuracy was evaluated principally based on positive predictive value (PPV) and sensitivity. RESULTS: Among 357 study subjects, 82 (23%) met the gold standard for hospitalized FN. For the claims-based definition including diagnosis codes for neutropenia plus fever in any position (n=28), PPV was 100% and sensitivity was 34% (95% CI: 24-45). For the definition including neutropenia in the primary position (n=54), PPV was 87% (78-95) and sensitivity was 57% (46-68). For the definition including neutropenia in any position (n=71), PPV was 77% (68-87) and sensitivity was 67% (56-77). CONCLUSIONS: Patients hospitalized for chemotherapy-induced FN can be identified in healthcare claims databases--with an acceptable level of mis-classification--using diagnosis codes for neutropenia, or neutropenia plus fever.


Asunto(s)
Antineoplásicos/efectos adversos , Bases de Datos Factuales , Fiebre/inducido químicamente , Fiebre/clasificación , Revisión de Utilización de Seguros , Neutropenia/inducido químicamente , Neutropenia/clasificación , Anciano , Factores Estimulantes de Colonias/uso terapéutico , Intervalos de Confianza , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad
4.
BMC Cancer ; 13: 11, 2013 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-23298389

RESUMEN

BACKGROUND: Myelosuppressive chemotherapy can lead to dose-limiting febrile neutropenia. Prophylactic use of recombinant human G-CSF such as daily filgrastim and once-per-cycle pegfilgrastim may reduce the incidence of febrile neutropenia. This comparative study examined the effect of pegfilgrastim versus daily filgrastim on the risk of hospitalization. METHODS: This retrospective United States claims analysis utilized 2004-2009 data for filgrastim- and pegfilgrastim-treated patients receiving chemotherapy for non-Hodgkin's lymphoma (NHL) or breast, lung, ovarian, or colorectal cancers. Cycles in which pegfilgrastim or filgrastim was administered within 5 days from initiation of chemotherapy (considered to represent prophylaxis) were pooled for analysis. Neutropenia-related hospitalization and other healthcare encounters were defined with a "narrow" criterion for claims with an ICD-9 code for neutropenia and with a "broad" criterion for claims with an ICD-9 code for neutropenia, fever, or infection. Odds ratios (OR) for hospitalization and 95% confidence intervals (CI) were estimated by generalized estimating equation (GEE) models and adjusted for patient, tumor, and treatment characteristics. Per-cycle healthcare utilization and costs were examined for cycles with pegfilgrastim or filgrastim prophylaxis. RESULTS: We identified 3,535 patients receiving G-CSF prophylaxis, representing 12,056 chemotherapy cycles (11,683 pegfilgrastim, 373 filgrastim). The mean duration of filgrastim prophylaxis in the sample was 4.8 days. The mean duration of pegfilgrastim prophylaxis in the sample was 1.0 day, consistent with the recommended dosage of pegfilgrastim - a single injection once per chemotherapy cycle. Cycles with prophylactic pegfilgrastim were associated with a decreased risk of neutropenia-related hospitalization (narrow definition: OR = 0.43, 95% CI: 0.16-1.13; broad definition: OR = 0.38, 95% CI: 0.24-0.59) and all-cause hospitalization (OR = 0.50, 95% CI: 0.35-0.72) versus cycles with prophylactic filgrastim. For neutropenia-related utilization by setting of care, there were more ambulatory visits and hospitalizations per cycle associated with filgrastim prophylaxis than with pegfilgrastim prophylaxis. Mean per-cycle neutropenia-related costs were also higher with prophylactic filgrastim than with prophylactic pegfilgrastim. CONCLUSIONS: In this comparative effectiveness study, pegfilgrastim prophylaxis was associated with a reduced risk of neutropenia-related or all-cause hospitalization relative to filgrastim prophylaxis.


Asunto(s)
Antineoplásicos/efectos adversos , Factor Estimulante de Colonias de Granulocitos/administración & dosificación , Hospitalización , Neoplasias/tratamiento farmacológico , Neutropenia/prevención & control , Adulto , Anciano , Análisis Costo-Beneficio , Esquema de Medicación , Costos de los Medicamentos , Femenino , Filgrastim , Factor Estimulante de Colonias de Granulocitos/economía , Costos de Hospital , Hospitalización/economía , Humanos , Seguro de Servicios Farmacéuticos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Neoplasias/economía , Neutropenia/inducido químicamente , Neutropenia/economía , Oportunidad Relativa , Polietilenglicoles , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/economía , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos
5.
Exp Ther Med ; 2(5): 859-866, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22977589

RESUMEN

The average total hospitalization costs for adult cancer patients with neutropenic complications were quantified and the average length of hospital stay (LOS), all-cause mortality during hospitalization and reimbursement rates were determined. This observational retrospective cohort study identified adult patients with cancer who were hospitalized from January 2005 through June 2008 using a large private US health care database (>342 inpatient facilities). ICD-9-CM diagnosis codes identified patients by cancer type and who had neutropenic complications. The utilization and accounting systems of the hospitals were used to calculate mean (±95% confidence interval) hospitalization costs and LOS and percent all-cause mortality and reimbursement. Costs were adjusted to 2009 US dollars. There were 3,814 patients who had cancer and neutropenia, 1,809 (47.4%) also had an infection or fever and 1,188 (31.1%) had infection. Mean hospitalization costs were $18,042 (95% CI 16,997-19,087) for patients with neutropenia, $22,839 (95% CI 21,006-24,672) for patients with neutropenia plus infection or fever and $27,587 (95% CI 24,927-30,247) for patients with neutropenia plus infection. Mean LOS were 9 days (95% CI 8.7-9.3), 10.7 days (95% CI 10.2-11.2) and 12.6 days (95% CI 11.9-13.3), respectively. Mortality followed a similar trend; 8.3, 13.7 and 19.4%, respectively. By cancer type, hematologic malignancies had the highest average hospitalization costs and longest mean LOS of $52,579 (95% CI 42,183-62,975) and 20.3 days (95% CI 17.4-23.2), and a high mortality rate of 20.0%, while primary breast cancer patients had the lowest cost of $8,413 (95% CI 6,103-10,723), shortest LOS of 5.5 days (95% CI 4.2-6.8) and lowest mortality (0%). Mean reimbursement rates were 100.0, 101.5 and 95.4% for patients with neutropenia, neutropenia plus infection or fever and neutropenia plus infection, respectively. Hospitalized cancer patients with neutropenic complications had a higher all-cause mortality rate and higher inpatient hospitalization costs than those previously published. Results from this study suggest that costs for inpatient hospitalized cancer patients with neutropenic complications are principally reimbursed by payers.

6.
J Clin Oncol ; 27(5): 672-80, 2009 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-19114685

RESUMEN

PURPOSE: Panitumumab, a fully human antibody targeting the epidermal growth factor receptor, is active in patients with metastatic colorectal cancer (mCRC). This trial evaluated panitumumab added to bevacizumab and chemotherapy (oxaliplatin- and irinotecan-based) as first-line treatment for mCRC. PATIENTS AND METHODS: Patients were randomly assigned within each chemotherapy cohort to bevacizumab and chemotherapy with or without panitumumab 6 mg/kg every 2 weeks. The primary end point was progression-free survival (PFS) within the oxaliplatin cohort. Tumor assessments were performed every 12 weeks and reviewed centrally. RESULTS: A total of 823 and 230 patients were randomly assigned to the oxaliplatin and irinotecan cohorts, respectively. Panitumumab was discontinued after a planned interim analysis of 812 oxaliplatin patients showed worse efficacy in the panitumumab arm. In the final analysis, median PFS was 10.0 and 11.4 months for the panitumumab and control arms, respectively (HR, 1.27; 95% CI, 1.06 to 1.52); median survival was 19.4 months and 24.5 months for the panitumumab and control arms, respectively. Grade 3/4 adverse events in the oxaliplatin cohort (panitumumab v control) included skin toxicity (36% v 1%), diarrhea (24% v 13%), infections (19% v 10%), and pulmonary embolism (6% v 4%). Increased toxicity without evidence of improved efficacy was observed in the panitumumab arm of the irinotecan cohort. KRAS analyses showed adverse outcomes for the panitumumab arm in both wild-type and mutant groups. CONCLUSION: The addition of panitumumab to bevacizumab and oxaliplatin- or irinotecan-based chemotherapy results in increased toxicity and decreased PFS. These combinations are not recommended for the treatment of mCRC in clinical practice.


Asunto(s)
Anticuerpos Monoclonales/administración & dosificación , Antineoplásicos/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Neoplasias Colorrectales/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales Humanizados , Bevacizumab , Camptotecina/administración & dosificación , Camptotecina/análogos & derivados , Neoplasias Colorrectales/mortalidad , Femenino , Humanos , Irinotecán , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Compuestos Organoplatinos/administración & dosificación , Oxaliplatino , Panitumumab
7.
In Vivo ; 21(5): 707-13, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18019402

RESUMEN

BACKGROUND: We hypothesized that subset classification of Epstein-Barr virus (EBV) in chronic fatigue syndrome (CFS) is required. At first, a blinded-random placebo-controlled trial of valacyclovir in EBV CFS subset was performed (Group 1), and this EBV subset was followed for thirty-six months (Group 2). Patients were given valacyclovir at 14.3 mg/kg every 6 hours. The validated Energy Index (EI) point score assessing physical functional capacity, Holter monitor, multigated (radionuclide) MUGA rest/stress ventriculographic examination, EBV serum IgM viral capsid antibodies (VCA), and EBV early antigen diffuse (EA) were followed. After six-months, Group 1 CFS patients receiving valacyclovir experienced an increased mean least square EI point score +1.12 units (122 kcal/day), while the placebo cohort increased +0.42 EI units (65 kcal/day). EI point scores at Group 2 increased progressively. Sinus tachycardias decreased and abnormal cardiac wall motion improved. Serum antibody titers to EBV VCA IgM decreased. Patients resumed normal activities.


Asunto(s)
Aciclovir/análogos & derivados , Antivirales/uso terapéutico , Síndrome de Fatiga Crónica/tratamiento farmacológico , Síndrome de Fatiga Crónica/virología , Herpesvirus Humano 4/efectos de los fármacos , Mononucleosis Infecciosa/tratamiento farmacológico , Mononucleosis Infecciosa/virología , Valina/análogos & derivados , Aciclovir/efectos adversos , Aciclovir/uso terapéutico , Adolescente , Adulto , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Electrocardiografía , Síndrome de Fatiga Crónica/líquido cefalorraquídeo , Síndrome de Fatiga Crónica/inmunología , Femenino , Estudios de Seguimiento , Corazón/efectos de los fármacos , Corazón/fisiología , Herpesvirus Humano 4/inmunología , Humanos , Mononucleosis Infecciosa/líquido cefalorraquídeo , Mononucleosis Infecciosa/inmunología , Masculino , Persona de Mediana Edad , Actividad Motora/efectos de los fármacos , Factores de Tiempo , Valaciclovir , Valina/efectos adversos , Valina/uso terapéutico
8.
Am J Obstet Gynecol ; 194(3): 774-81, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16522412

RESUMEN

OBJECTIVE: The purpose of this study was to estimate the efficacy of valacyclovir suppressive therapy in pregnant women with recurrent genital herpes. STUDY DESIGN: At 36 weeks' gestation, herpes simplex virus (HSV)-2 seropositive women were randomized to receive oral valacyclovir 500 mg or placebo twice daily until delivery. Genital tract and neonatal specimens were collected weekly for HSV culture and qualitative polymerase chain reaction (PCR) assay to detect viral DNA from the time of randomization to delivery. Both maternal and neonatal toxicity measures were obtained. RESULTS: The 112 enrolled women (57 valacyclovir, 55 placebo) had similar HSV recurrence risks, including mean number of active HSV recurrences before randomization during the index pregnancy (1.1 +/- 1.9 vs 1.5 +/- 2.1, P = .308) and days between randomization and delivery (20.3 +/- 10.2 vs 22.0 +/- 8.9, P = .344). The number of women with clinical HSV recurrences between the time of randomization and delivery was significantly lower in the valacyclovir versus placebo group (10.5% vs 27.3%; P = .023, RR 0.4, 95% CI 0.2-0.9). Shedding of HSV within 7 days of delivery was similar in the valacyclovir and placebo group (10.4% vs 12.0%, P = .804; RR 0.9, 95% CI 0.3-2.7), as was the number of women with clinical HSV lesions at delivery (5.3% vs 14.6%, P = .121; RR 0.4, 95% CI 0.1-1.3). No neonates had symptomatic congenital HSV infection before discharge or up to 2 weeks' postpartum, and no clinical or laboratory safety concerns were identified. CONCLUSION: Administration of valacyclovir beginning at 36 weeks' gestation to women with a history of recurrent genital HSV reduced the number of women with subsequent clinical HSV recurrences.


Asunto(s)
Aciclovir/análogos & derivados , Antivirales/uso terapéutico , Herpes Genital/prevención & control , Complicaciones Infecciosas del Embarazo/prevención & control , Valina/análogos & derivados , Aciclovir/uso terapéutico , Adulto , Método Doble Ciego , Femenino , Humanos , Recién Nacido , Embarazo , Recurrencia , Valaciclovir , Valina/uso terapéutico
9.
In Vivo ; 18(4): 417-24, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15369178

RESUMEN

We reported unique incomplete herpesvirus (Epstein-Barr Virus (EBV) and/or nonstructural (HCMV) cytomegalovirus) multiplication in 2 distinct subsets of CFS patients. The CFS subsets were identified by: a) presence of IgM serum antibodies to HCMV nonstructural gene products p52 and CM2 (UL44 and UL57), and/or b) IgM serum antibodies to Epstein-Barr virus viral capsid antigen (EBV, VCA IgM). Diagnostic IgM serum antibodies were found in two independent blinded studies involving 49 CFS patients, but the same antibodies were absent in 170 control patients (p<0.05). Abnormal 24 Hr-electrocardiographic monitoring, tachycardias at rest and, in severe chronic cases, abnormal cardiac wall motion (ACWM) were seen in these same CFS patients. We now report a prospective consecutive case control study from 1987--1999 of cardiac dynamics as measured by radionuclide ventriculography in 98 CFS patients from 1987--1999. Controls were patients with various malignancies who were evaluated in protocols requiring radionuclide ventriculography before initiation of cardiotoxic chemotherapeutic agents. The prevalence of abnormal cardiac wall motion (ACWM) at rest in CFS patients was 10 out of 87 patients (11.5%). With stress exercise, 21 patients (24.1%) demonstrated ACWM. Cardiac biopsies in 3 of these CFS patients with ACWM showed a cardiomyopathy. Among the controls, ACWM at rest was present in 4 out of 191 patients (2%) (p=0.0018). A progressive cardiomyopathy caused by incomplete virus multiplication of EBV and/or HCMV in CFS patients is present.


Asunto(s)
Cardiomiopatías/fisiopatología , Infecciones por Citomegalovirus/fisiopatología , Infecciones por Virus de Epstein-Barr/fisiopatología , Síndrome de Fatiga Crónica/fisiopatología , Disfunción Ventricular Derecha/fisiopatología , Adulto , Anticuerpos Antivirales/sangre , Antígenos Virales/inmunología , Cardiomiopatías/complicaciones , Citomegalovirus/inmunología , Infecciones por Citomegalovirus/complicaciones , Infecciones por Citomegalovirus/inmunología , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/inmunología , Síndrome de Fatiga Crónica/complicaciones , Síndrome de Fatiga Crónica/virología , Femenino , Herpesvirus Humano 4/inmunología , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Método Simple Ciego , Taquicardia/complicaciones , Taquicardia/fisiopatología , Disfunción Ventricular Derecha/complicaciones
10.
In Vivo ; 18(2): 101-6, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15113035

RESUMEN

BACKGROUND: A unique subset of patients with chronic fatigue syndrome (CFS) and IgM serum antibodies to cytomegalovirus (HCMV) non-structural gene products p52 and CM2 (UL 44 and UL 57) has been described. PATIENTS AND METHODS: Fifty-eight CFS patients and 68 non-CFS matched controls were studied. Serum antibodies to EBV viral capsid antigen (VCA) IgM and EBV Early Antigen, diffuse (EA, D) as well HVCMV(V), IgM and IgG; VP (sucrose, density purified V); p52 and CM2 IgM serum antibodies were assayed. RESULTS: Mean age of CFS patients was 44 years (75% women). Control patients were 9 years older (73% women). Serum EBV VCA IgM positive antibody titers were identified in 33 CFS patients (Group A subset EBV VCA IgM 62.3+/-8.3, neg. <20), but were not present in other CFS patients, (Group B subset EBV VCA IgM 6.8+/-0.7) controls (p<0.0001). EBV VCA IgM titers remained positive in CFS patients from Group A for 24-42 months. CONCLUSION: Serum antibody to EBV VCA IgM may be a specific diagnostic test for a second subset of CFS patients.


Asunto(s)
Anticuerpos Antivirales/sangre , Infecciones por Virus de Epstein-Barr/inmunología , Síndrome de Fatiga Crónica/inmunología , Herpesvirus Humano 4/inmunología , Inmunoglobulina M/sangre , Adulto , Anciano , Antígenos Virales/inmunología , Proteínas de la Cápside/inmunología , Citomegalovirus/inmunología , Ensayo de Inmunoadsorción Enzimática , Infecciones por Virus de Epstein-Barr/complicaciones , Síndrome de Fatiga Crónica/virología , Femenino , Humanos , Masculino , Persona de Mediana Edad
11.
In Vivo ; 16(3): 153-9, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12182109

RESUMEN

Human cytomegalovirus (HCMV) IgM serum antibodies to two nonstructural gene products UL44 and UL57 (p52 and CM2) were assayed in patients with the diagnosis of the chronic fatigue syndrome (CFS) according to criteria established by the US Centers for Disease Control and Prevention. A subset of 16 CFS patients demonstrated HCMV IgG, but no HCMV IgM serum antibodies to conformational structural HCMV antigens (designated, V). By convention, these findings are interpreted to indicate only a remote HCMV infection. However, HCMV IgM p52 and CM2 antibodies were uniquely present in these 16 CFS patients. Other CFS patients with similar HCMV (V) IgG antibodies (18 patients), non-fatigued HCMV (V) IgG-positive control patients (18 patients), random HCMV (V) IgG-positive control patients from a clinical laboratory (26 patients), and non-fatigued HCMV (V) IgG-negative control patients (15 patients) did not have HCMV, IgM p52 or CM2 serum antibodies (p < 0.05). Control HCMV (V) IgG-positive patients had no serum IgM HCMV (V) antibodies to conventional structural HCMV (V) antigen. Thus, 77 various control patients did not contain IgM p52 or CM2 serum antibodies. The presence of IgM p52 and/or CM2 HCMV serum antibodies in this subset of CSF-specific patients may detect incomplete HCMV multiplication in which a part of the HCMV protein-coding content of the HCMV genome is processed, but remains unassembled. These findings suggest that the presence of HCMV IgM p52 and CM2 serum antibodies may be a specific diagnostic test for the diagnosis of a subset of CFS patients. Further, these data suggest an etiologic relationship for HCMV infection in this group of CFS patients.


Asunto(s)
Infecciones por Citomegalovirus/inmunología , Proteínas de Unión al ADN/inmunología , Síndrome de Fatiga Crónica/inmunología , Inmunoglobulina M/inmunología , Proteínas Recombinantes de Fusión/inmunología , Proteínas Virales/inmunología , Anciano , Antígenos Virales/inmunología , Citomegalovirus/inmunología , Citomegalovirus/aislamiento & purificación , Infecciones por Citomegalovirus/complicaciones , Ensayo de Inmunoadsorción Enzimática , Síndrome de Fatiga Crónica/complicaciones , Femenino , Humanos , Masculino , Persona de Mediana Edad
12.
Drugs R D ; 3(6): 365-73, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12516939

RESUMEN

OBJECTIVE: Valaciclovir has in vitro activity against Epstein-Barr virus (EBV) and, because of improved absorption with higher achievable serum concentrations, may be more effective than aciclovir in the treatment of EBV. No studies to date have evaluated the efficacy, safety or proper dosing of valaciclovir in children for the treatment of EBV infection. The objectives of this study were to determine the pharmacokinetics and safety of valaciclovir tablets and suspension in children with EBV illness. METHODS: 24 children with EBV illness were randomised to receive valaciclovir suspension 10 mg/kg or 20 mg/kg; eight children subsequently were crossed over and also received valaciclovir 500 mg tablets. Doses of either suspension or tablets were administered every 8 hours for four doses, and pharmacokinetic studies were performed to determine aciclovir serum concentrations. Samples for drug assay were obtained at 0, 0.5, 1, 2, 4, 6, 8 and 24 hours. Samples were assayed by high performance liquid chromatography (HPLC) methods and aciclovir pharmacokinetics determined using non-compartmental analysis. RESULTS: Valaciclovir pharmacokinetic parameters (mean +/- SD) in children who received tablets and suspension (normalised to 500 mg dose) were: maximum serum concentration (C(max)) 3.16 +/- 1.30 and 2.42 +/- 0.74 mg/L, time to maximum serum concentration (t(max)) 1.88 +/- 0.99 and 1.31 +/- 0.53 hours, half-life (t 1/2) 1.72 +/- 0.41 and 1.94 +/- 0.60 hours, apparent total systemic clearance (CL/F) 20.01 +/- 6.61 and 15.58 +/- 3.34 ml/min/kg, volume of distribution/bioavailability (Vd/F) 3.04 +/- 1.26 and 2.58 +/- 0.81 L/kg, and area under the concentration-time curve (AUC) 10.13 +/- 3.47 and 8.59 +/- 2.52 mg x h/L, respectively. There were no statistically significant differences in the pharmacokinetics of valaciclovir tablets versus suspension. The relative bioavailability of the valaciclovir tablets compared with the suspension was 115 +/- 32%. Valaciclovir was well tolerated, with gastrointestinal disturbances and headache being the most common adverse effects in a small number of subjects. CONCLUSIONS: Valaciclovir is absorbed and achieves concentrations in children that appear to be effective for the treatment of herpes lesions. The pharmacokinetics of valaciclovir suspension and tablets are similar, and the pharmacokinetics of aciclovir after administration of valaciclovir to children are similar to historical observations of aciclovir pharmacokinetics in adults. Valaciclovir has a good safety profile and was well tolerated after oral administration in this group of children.


Asunto(s)
Aciclovir/análogos & derivados , Aciclovir/farmacocinética , Antivirales/farmacocinética , Infecciones por Virus de Epstein-Barr/tratamiento farmacológico , Valina/análogos & derivados , Valina/farmacocinética , Aciclovir/administración & dosificación , Aciclovir/efectos adversos , Aciclovir/sangre , Aciclovir/uso terapéutico , Administración Oral , Adolescente , Antivirales/administración & dosificación , Antivirales/efectos adversos , Antivirales/sangre , Antivirales/uso terapéutico , Disponibilidad Biológica , Niño , Preescolar , Estudios Cruzados , Femenino , Herpesvirus Humano 4/efectos de los fármacos , Humanos , Absorción Intestinal , Masculino , Suspensiones , Comprimidos , Valaciclovir , Valina/administración & dosificación , Valina/efectos adversos , Valina/sangre , Valina/uso terapéutico
13.
Drugs Today (Barc) ; 38(8): 549-61, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12582420

RESUMEN

This study was designed to determine safety and efficacy of a 6-month trial of valacyclovir in single-virus Epstein-Barr virus (EBV) persistent infection. Phase I of this study used four specific criteria to define a subset of patients with chronic fatigue syndrome (CFS). In the second phase, myocardial dynamics were measured by MUGA rest/stress radionuclide ventriculographic (RVG) examinations pre- and posttreatment with valacyclovir. In phase I, a trial was performed in 19 consecutive CFS patients with the following diagnostic conditions: patients met criteria for diagnosis of CFS; they had had CFS for less than 1 year. They demonstrated repetitively abnormal oscillating T waves (ischemic or flat) at 24-h Holter monitoring; and they had elevated serum IgM antibody titers to EBV viral capsid antigen and/or total diffuse early antigen as measured by the enzyme-linked immunosorbent assay method. The treatment group comprised 10 CFS patients with no serum antibodies to human cytomegalovirus, but the control group (nine CFS patients) had, additionally, high titers of serum antibodies (IgG) to conformational structural antigens of human cytomegalovirus. Both the parallel treatment and control CFS groups received valacyclovir 1.0-1.5 gm q.6.h. for 6 months. This valacyclovir dose achieved serum acyclovir C(max) of > 7 microm and high antiviral activity versus EBV (IC(50) of 4.4-13.3 m). In phase II, six additional CFS patients met the same four criteria as the 19 CFS patients in phase I. They had, however, been ill for a mean of 55.8 months. Thus, 25 CFS patients comprise this study. The studies were carried out at a single outpatient practice in Birmingham, MI, U.S.A. Before initiating valacyclovir, and after 6 months of treatment, clinical and laboratory observations were made. The CFS Energy Index point score (Table I) was used to record each CFS patient's functional capacity at baseline and after 1, 3 and 6 months of valacyclovir. Energy Index point scores, as well as EBV and human cytomegalovirus serum antibody titers were assessed. In the second phase, left ventricular dynamics were repeated after 6 months of treatment with valacyclovir. We concluded that the 16 CFS patients (included in both phases of this study) with EBV-persistent infection (EBV single-virus subset) are improved after 6 months of continuous pharmacokinetic dosing with valacyclovir. Nine CFS patients with EBV/human cytomegalovirus co-infection did not benefit from 6 months of similar treatment. Valacyclovir is not an effective anti-human cytomegalovirus antiviral drug. Unimproved CFS patients with co-infections EBV and human cytomegalovirus may require combined treatment with valacyclovir and another drug more active against human cytomegalovirus. This preliminary trial, with a small number of patients, may be critical to an appropriately designed larger, double-blind, placebo-controlled trial.


Asunto(s)
Aciclovir/análogos & derivados , Aciclovir/uso terapéutico , Ensayos Clínicos como Asunto , Infecciones por Virus de Epstein-Barr/tratamiento farmacológico , Síndrome de Fatiga Crónica/tratamiento farmacológico , Valina/análogos & derivados , Valina/uso terapéutico , Función Ventricular Izquierda/efectos de los fármacos , Aciclovir/farmacología , Distribución de Chi-Cuadrado , Ensayos Clínicos como Asunto/estadística & datos numéricos , Infecciones por Virus de Epstein-Barr/sangre , Síndrome de Fatiga Crónica/sangre , Herpesvirus Humano 4/efectos de los fármacos , Herpesvirus Humano 4/metabolismo , Humanos , Valaciclovir , Valina/farmacología , Función Ventricular Izquierda/fisiología
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