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1.
Clin Infect Dis ; 69(11): 1969-1979, 2019 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-30715261

RESUMEN

BACKGROUND: (Pegylated) Interferon ([Peg]IFN) therapy leads to response in a minority of chronic hepatitis B (CHB) patients. Host genetic determinants of response are therefore in demand. METHODS: In this genome-wide association study (GWAS), CHB patients, treated with (Peg)IFN for at least 12 weeks ± nucleos(t)ide analogues within randomized trials or as standard of care, were recruited at 21 centers from Europe, Asia, and North America. Response at 24 weeks after (Peg)IFN treatment was defined as combined hepatitis B e antigen (HBeAg) loss with hepatitis B virus (HBV) DNA <2000 IU/mL, or an HBV DNA <2000 IU/mL for HBeAg-negative patients. RESULTS: Of 1144 patients, 1058 (92%) patients were included in the GWAS analysis. In total, 282 (31%) patients achieved the response and 4% hepatitis B surface antigen (HBsAg) loss. GWAS analysis stratified by HBeAg status, adjusted for age, sex, and the 4 ancestry components identified PRELID2 rs371991 (B= -0.74, standard error [SE] = 0.16, P = 3.44 ×10-6) for HBeAg-positive patients. Importantly, PRELID2 was cross-validated for long-term response in HBeAg-negative patients. G3BP2 rs3821977 (B = 1.13, SE = 0.24, P = 2.46 × 10-6) was associated with response in HBeAg-negative patients. G3BP2 has a role in the interferon pathway and was further examined in peripheral blood mononuclear cells of healthy controls stimulated with IFNα and TLR8. After stimulation, less production of IP-10 and interleukin (IL)-10 proteins and more production of IL-8 were observed with the G3BP2 G-allele. CONCLUSIONS: Although no genome-wide significant hits were found, the current GWAS identified genetic variants associated with (Peg)IFN response in CHB. The current findings could pave the way for gene polymorphism-guided clinical counseling, both in the setting of (Peg)IFN and the natural history, and possibly for new immune-modulating therapies. CLINICAL TRIALS REGISTATION: NCT01401400.


Asunto(s)
Estudio de Asociación del Genoma Completo/métodos , Virus de la Hepatitis B/patogenicidad , Hepatitis B Crónica/tratamiento farmacológico , Interferón-alfa/metabolismo , Interferones/metabolismo , Adulto , Antivirales/uso terapéutico , Femenino , Técnicas de Genotipaje , Virus de la Hepatitis B/efectos de los fármacos , Hepatitis B Crónica/virología , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios Prospectivos
2.
Int J Radiat Oncol Biol Phys ; 59(4): 1107-15, 2004 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-15234045

RESUMEN

PURPOSE: To investigate the maximal tolerated dose of a continuous 28-day iododeoxyuridine (IUdr) infusion combined with hyperfractionated accelerated radiotherapy (HART); to analyze the percentage of IUdr-thymidine replacement in peripheral granulocytes as a surrogate marker for IUdr incorporation into tumor cells; to measure the steady-state serum IUdr levels; and to assess the feasibility of continuous IUdr infusion and HART in the management of malignant glioma. METHODS AND MATERIALS: Patients were required to have biopsy-proven malignant glioma. Patients received 100 (n = 4), 200 (n = 3), 300 (n = 3), 400 (n = 6), 500 (n = 4), 625 (n = 5), or 781 (n = 6) mg/m(2)/d of IUdr by continuous infusion for 28 days. HART was started 7 days after IUdr initiation. The total dose was 70 Gy (1.2 Gy b.i.d. for 25 days with a 10-Gy boost [2.0 Gy for 5 Saturdays]). Weekly assays were performed to determine the percentage of IUdr-DNA replacement in granulocytes and serum IUdr levels using standard high performance liquid chromatography methods. Standard Phase I toxicity methods were used. RESULTS: Between June 1994 and August 1999, 31 patients were enrolled. No patient had Grade 3 or worse HART toxicity. Grade 3 or greater IUdr toxicity predominantly included neutropenia (n = 3), thrombocytopenia (n = 3), and elevated liver function studies (n = 3). The maximal tolerated dose was 625 mg/m(2)/d. Thymidine replacement in the peripheral granulocytes peaked at 3 weeks and increased with the dose (maximal thymidine replacement 4.9%). The steady-state plasma IUdr level increased with the dose (maximum, 1.5 microM). CONCLUSION: In our study, continuous long-term IUdr i.v. infusion had a maximal tolerated dose of 625 mg/m(2)/d. Granulocyte incorporation data verified the concept that prolonged IUdr infusion results in IUdr-DNA replacement that corresponds to a high degree of cell labeling. IUdr steady-state plasma levels increased with increasing dose and attained levels needed for clinical radiosensitization. Continuous IUdr infusion and HART were both feasible and well tolerated.


Asunto(s)
Astrocitoma/radioterapia , Neoplasias Encefálicas/radioterapia , Idoxuridina/administración & dosificación , Fármacos Sensibilizantes a Radiaciones/administración & dosificación , Adulto , Anciano , Astrocitoma/metabolismo , Neoplasias Encefálicas/metabolismo , Fraccionamiento de la Dosis de Radiación , Femenino , Humanos , Idoxuridina/efectos adversos , Idoxuridina/farmacocinética , Infusiones Intravenosas , Estado de Ejecución de Karnofsky , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Fármacos Sensibilizantes a Radiaciones/efectos adversos , Fármacos Sensibilizantes a Radiaciones/farmacocinética
3.
Cancer Chemother Pharmacol ; 54(4): 368-76, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15205914

RESUMEN

PURPOSE: Perillyl alcohol (POH) has been shown to have both chemopreventative and chemotherapeutic activities in preclinical studies. The underlying mechanism(s) of action of POH have yet to be delineated but may involve effects on the transforming growth factor beta (TGFbeta) and/or the Ras signaling pathways. A phase I study of POH for 14 days out of every 28 days in subjects with advanced malignancies was performed to evaluate dose escalation, toxicity, pharmacokinetics, and effects on TGFbeta and Ras. METHODS: POH was administered orally (500 mg capsules containing 250 mg POH) to 20 patients four times a day on a continuous basis for 14 days followed by a 14-day rest period, for up to three courses. The starting dose was 1200 mg/m(2) per dose. A minimum of three patients were treated and evaluated at each escalating POH dose. Pharmacokinetic analysis was performed on days 1 and 14 of course 1 and day 1 of selected later courses. Plasma TGFbeta levels were measured on days 1 and 14. Peripheral blood lymphocyte (PBLs) Ras levels were assayed on days 1 and 2 of the first course. RESULTS: The 20 patients, of whom 15 were evaluable, received doses between 1200 and 2000 mg/m(2) per dose for a total of 43 courses. The most common observed toxicities were nausea, gastrointestinal distress, and fatigue. Other toxicities included diarrhea or constipation, hypokalemia, and one incidence of acute pancreatitis. Due to these toxicities, four of the patients declined further treatment either during or after the second course. While POH was not detected in plasma, perillic acid (PA) and dihydroperillic acid (DHPA) were detected in plasma, and the peak levels at 2000 mg/m(2) per dose were approximately 600 micro M (PA) and 50 micro M (DHPA). There was some evidence for linearity in the peak plasma levels and area under the concentration-time curve of the metabolites from the starting dose to the highest dose. Metabolite pharmacokinetics were not significantly affected by ingestion in the fed or fasting state, or repeated exposure to POH. No evidence for an effect of POH on plasma TGFbeta or PBL Ras protein was observed. No objective responses were observed. CONCLUSIONS: In adults with advanced malignancies, an interrupted administration schedule of POH did not reveal significant advantages over continuous dosing schedules.


Asunto(s)
Antineoplásicos/administración & dosificación , Monoterpenos/administración & dosificación , Adulto , Anciano , Antineoplásicos/efectos adversos , Antineoplásicos/farmacocinética , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/efectos adversos , Inhibidores Enzimáticos/farmacocinética , Femenino , Humanos , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Monoterpenos/efectos adversos , Monoterpenos/farmacocinética , Neoplasias
4.
Cancer Chemother Pharmacol ; 50(6): 465-72, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12451473

RESUMEN

PURPOSE: Flavopiridol (NSC 649890) is a synthetic flavone possessing significant antitumor activity in preclinical models. Flavopiridol is capable of inducing cell cycle arrest and apoptosis, presumably through its potent, specific inhibition of cyclin-dependent kinases. We conducted a phase I trial and pharmacokinetic study of flavopiridol given as a 72-h continuous intravenous infusion repeated every 2 weeks. METHODS: A total of 38 patients were treated at dose levels of 8, 16, 26.6, 40, 50 and 56 mg/m(2)/24 h. During the first infusion, plasma was sampled at 24, 48 and 72 h to determine steady-state concentrations, and peripheral blood lymphocytes were assessed by flow cytometry for evidence of apoptosis. Additional postinfusion pharmacokinetic sampling was done at the 40 and 50 mg/m(2)/24 h dose levels. RESULTS: Gastrointestinal toxicity was dose limiting, with diarrhea being the predominant symptom. Symptomatic orthostatic hypotension was also frequently noted. Several patients experienced tumor-specific pain during their infusions. The maximum tolerated dose (MTD) was determined to be 40 mg/m(2)/24 h. A patient with metastatic gastric cancer at this dose level had a complete response and remained disease-free for more than 48 months after completing therapy. Plasma concentrations at 24 h into the infusion were 94% of those achieved at steady state. Steady-state plasma flavopiridol concentrations at the MTD were 416.6+/-98.9 micro M. These concentrations are at or above those needed to see cell cycle arrest and apoptosis in vitro. The mean clearance of flavopiridol over the dose range was 11.3+/-3.9 l/h per m(2), similar to values obtained preclinically. Elimination was biphasic. The terminal half-life at the MTD was 26.0 h. No significant differences in pharmacokinetic parameters were noted between males and females. Patients taking cholestyramine to ameliorate flavopiridol-induced diarrhea had lower steady-state plasma concentrations. There was no significant change in the cell cycle parameters of peripheral blood lymphocytes analyzed by flow cytometry. CONCLUSIONS: The MTD and recommended phase II dose of flavopiridol given by this schedule is 40 mg/m(2)/24 h. The manageable gastrointestinal toxicity, early signs of clinical activity and lack of hematologic toxicity make further exploration in combination trials warranted.


Asunto(s)
Antineoplásicos/farmacocinética , Quinasas Ciclina-Dependientes/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacocinética , Flavonoides/farmacocinética , Neoplasias/metabolismo , Piperidinas/farmacocinética , Adulto , Anciano , Anciano de 80 o más Años , Relación Dosis-Respuesta a Droga , Femenino , Citometría de Flujo , Semivida , Humanos , Infusiones Intravenosas , Masculino , Dosis Máxima Tolerada , Tasa de Depuración Metabólica , Persona de Mediana Edad , Neoplasias/tratamiento farmacológico , Seguridad , Resultado del Tratamiento
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