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1.
Clin Infect Dis ; 33(5): 597-602, 2001 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-11477525

RESUMO

Genital condylomata acuminata are nonmalignant human papillomavirus (HPV)-induced tumors in which HPV types 6 and 11 are most commonly found. Usual treatments for condylomata acuminata are nonspecific and are based on the destruction or removal of infected tissue. These procedures are often painful and are characterized by a high relapse rate. We report here what is to our knowledge the first double-blind, placebo-controlled study of the use of cidofovir, a nucleotide analogue, for the treatment of genital papillomavirus infections. Thirty patients were enrolled in the study; 19 received cidofovir, and 11 received placebo. The median number of warts and the median baseline wart area were comparable for both groups. Nine (47%) of 19 patients in the cidofovir group had a complete response (total healing), compared with 0 of the patients in the placebo group (P=.006). None of the patients in the cidofovir group experienced progression of the disease, compared with 5 (45%) of 11 patients in the placebo group. The side effects recorded for both groups were comparable.


Assuntos
Antivirais/uso terapêutico , Citosina/uso terapêutico , Organofosfonatos , Compostos Organofosforados/uso terapêutico , Papillomaviridae/efeitos dos fármacos , Infecções por Papillomavirus/tratamento farmacológico , Infecções Tumorais por Vírus/tratamento farmacológico , Adulto , Cidofovir , Citosina/análogos & derivados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Papillomaviridae/isolamento & purificação , Fatores de Risco , Resultado do Tratamento
2.
J Viral Hepat ; 6(5): 387-95, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10607255

RESUMO

Adefovir dipivoxil (bis-POM PMEA) is an adenine nucleotide analogue with activity against retroviruses and herpesviruses, and in vitro activity against hepatitis B virus (HBV). This study was conducted to evaluate its safety and antiviral activity in patients with chronic HBV infection. Twenty patients (13 co-infected with human immunodeficiency virus, HIV) were randomized in a phase I/II, double-blind, placebo-controlled study. Patients who had been hepatitis B surface antigen (HBsAg)/hepatitis B e antigen (HBeAg) positive for > or = 6 months, with elevated hepatic transaminases and serum HBV DNA > or = 50 pg ml-1, were randomized to adefovir dipivoxil 125 mg (n = 15) or placebo (n = 5) as a single, daily, oral dose for 28 days. Antiviral activity was assessed by changes in serum HBV DNA (using the Digene Hybrid Capture assay) and HBeAg/hepatitis B e antibody (HBeAb) status. HBV DNA levels fell rapidly by > 1 log10 in all active drug recipients (median fall 1.8 log10 pg ml-1) but increased by 0.01 log10 pg ml-1 in controls (P = 0.002). Reductions were sustained during treatment. HBV DNA returned to baseline over 1-6 weeks following discontinuation of active drug. HBeAg became transiently undetectable in one patient on treatment and, in another, sustained seroconversion to HBeAb occurred 12 weeks after treatment ended. Liver transaminase elevations > 300 U l-1 were observed in three patients during therapy (leading to protocol-specified treatment discontinuation or dose reduction) and in four patients during follow-up. On-treatment transaminase elevations were associated with HIV status, occurring in three of six HIV-uninfected patients compared with none of nine who were HIV infected. In addition, a slower return to baseline of serum HBV DNA levels was observed in the non-HIV-infected patients. Treatment for chronic hepatitis B as a once-daily oral dose was well tolerated and associated with significant and sustained reductions in serum HBV DNA levels during treatment. Transaminase elevations, which may be related to the therapeutic effect, were observed during and after treatment. Further studies are warranted to investigate the safety, and optimum dose and duration, of adefovir dipivoxil treatment for chronic hepatitis B.


Assuntos
Adenina/análogos & derivados , Antivirais/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Organofosfonatos , Adenina/efeitos adversos , Adenina/uso terapêutico , Adulto , Alanina Transaminase/sangue , Antivirais/efeitos adversos , DNA Viral/sangue , Método Duplo-Cego , Feminino , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/isolamento & purificação , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/virologia , Humanos , Masculino , Resultado do Tratamento , Carga Viral , Viremia/tratamento farmacológico
4.
Antimicrob Agents Chemother ; 43(2): 271-7, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9925517

RESUMO

The pharmacokinetics and bioavailability of 1-[((S)-2-hydroxy-2-oxo-1,4,2-dioxaphosphorinan-5-yl)methyl]cytosi ne (cyclic HPMPC) were examined at four doses in 22 patients with human immunodeficiency virus infection. Two groups of six patients received a single dose of cyclic HPMPC at 1.5 or 3.0 mg/kg of body weight by each of the oral and intravenous routes in a random order with a 2-week washout period between administrations. Additional patients received single intravenous doses of cyclic HPMPC at 5.0 mg/kg (n = 6) or 7.5 mg/kg (n = 4). Serial serum and urine samples were collected at intervals over 24 h after dosing. The concentrations of cyclic HPMPC and cidofovir in serum and urine samples were determined by validated reverse-phase ion-pairing high-performance liquid chromatography methods with derivatization and fluorescence detection. After intravenous administration of cyclic HPMPC, concentrations of cyclic HPMPC declined in a biexponential manner, with a mean +/- standard deviation half-life of 1.09 +/- 0.12 h (n = 22). The pharmacokinetics of cyclic HPMPC were independent of dose over the dose range of 1.5 to 7.5 mg/kg. The total clearance of cyclic HPMPC from serum and the volume of distribution of intravenous cyclic HPMPC were 198 +/- 39.6 ml/h/kg and 338 +/- 65.1 ml/kg, respectively (n = 22). The renal clearance of cyclic HPMPC (132 +/- 27.3 ml/h/kg; n = 22) exceeded the creatinine clearance (86.2 +/- 16.3 ml/h/kg), indicating active tubular secretion. The cyclic HPMPC excreted in urine in 24 h accounted for 71.3% +/- 16.0% of the administered dose. Cidofovir was formed from cyclic HPMPC in vivo with a time to the maximum concentration in serum of 1.64 +/- 0.23 h (n = 22). Cidofovir levels declined in an apparent monoexponential manner, with a mean terminal half-life of 3.98 +/- 1.26 h (n = 22). The cidofovir excreted in urine in 24 h accounted for 9.40% +/- 2.33% of the administered cyclic HPMPC dose. Exposure to cidofovir after intravenous administration of cyclic HPMPC was dose proportional and was 14.9% of that from an equivalent dose of cidofovir. The present study suggests that intravenous cyclic HPMPC also has a lower potential for nephrotoxicity in humans compared to that of intravenous cidofovir. The oral bioavailabilities of cyclic HPMPC were 1.76% +/- 1.48% and 3.10% +/- 1.16% with the administration of doses of 1.5 and 3.0 mg/kg, respectively (n = 6 per dose). The maximum concentrations of cyclic HPMPC in serum were 0.036 +/- 0.021 and 0.082 +/- 0.038 microgram/ml after the oral administration of doses of 1.5 and 3.0 mg/kg, respectively. Cidofovir reached quantifiable levels in the serum of only one patient for each of the 1.5- and 3.0-mg/kg oral cyclic HPMPC doses.


Assuntos
Fármacos Anti-HIV/farmacocinética , Citosina/análogos & derivados , Infecções por HIV/metabolismo , Organofosfonatos , Compostos Organofosforados/farmacocinética , Administração Oral , Adulto , Fármacos Anti-HIV/sangue , Fármacos Anti-HIV/metabolismo , Disponibilidade Biológica , Cidofovir , Citosina/sangue , Citosina/metabolismo , Citosina/farmacocinética , Feminino , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Compostos Organofosforados/sangue , Compostos Organofosforados/metabolismo , Pró-Fármacos/farmacocinética
5.
Antimicrob Agents Chemother ; 42(11): 2996-9, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9797239

RESUMO

A randomized, double-blind, clinic-initiated, sequential dose-escalation pilot study was performed to compare the safety and efficacy of single applications of 1, 3, and 5% cidofovir gel with placebo in the treatment of early, lesional, recurrent genital herpes at five Canadian outpatient sites. Ninety-six patients began treatment within 12 h of lesion appearance and were evaluated twice daily until healing of the lesion occurred. Cidofovir gel at all strengths significantly decreased the median time to negative virus culture in a dose-dependent fashion (3.0 days in the placebo group versus 2.2, 1.3, and 1.1 days in the 1, 3, and 5% cidofovir gel treatment groups, respectively; P = 0.02, 0.0001, and 0.0003, respectively). A trend toward a reduction in the median time to complete healing in association with treatment was present, but the differences were not statistically significant (5.0 days in the placebo group versus 4.3, 4.1, and 4.6 days in the 1, 3, and 5% cidofovir gel treatment groups, respectively). Application site reactions occurred in 3, 5, 19, and 22% of the patients in these four groups, respectively. Treatment-associated lesion recrudescence with delayed healing, which is suggestive of local toxicity, was observed in three patients treated with 5% cidofovir gel and one patient treated with 3% cidofovir gel. In summary, single-dose application of cidofovir gel confers a significant antiviral effect on lesions of recurrent genital herpes. Additional studies are warranted to further identify the optimal efficacious dose of cidofovir in association with the maximum gel strength that can be tolerated.


Assuntos
Antivirais/uso terapêutico , Citosina/análogos & derivados , Herpes Genital/tratamento farmacológico , Organofosfonatos , Compostos Organofosforados/uso terapêutico , Adulto , Idoso , Cidofovir , Citosina/administração & dosagem , Citosina/efeitos adversos , Citosina/uso terapêutico , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Géis , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Organofosforados/administração & dosagem , Compostos Organofosforados/efeitos adversos , Recidiva
6.
J Acquir Immune Defic Syndr Hum Retrovirol ; 17(4): 339-44, 1998 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-9525435

RESUMO

To assess the effect of intravenous cidofovir on delaying progression of previously treated, relapsing cytomegalovirus (CMV) retinitis, we conducted a randomized, controlled comparison of two maintenance dose levels of cidofovir. One hundred and fifty patients with AIDS and CMV retinitis that had progressed or was persistently active despite treatment with ganciclovir, foscarnet, or both were randomized to receive induction cidofovir, 5 mg/kg once weekly for 2 weeks, then maintenance therapy with either 5 mg/kg or 3 mg/kg once every other week. Concomitant probenecid and intravenous hydration were administered with each cidofovir dose. Retinitis progression was assessed in the first 100 patients by bilateral, full-field retinal photographs read at a central reading center by an ophthalmologist masked to treatment assignment. Incidence of side effects, changes in visual acuity, and mortality were also assessed. Median time to retinitis progression as assessed by retinal photography was not reached (95% confidence interval [CI], 115 days-upper limit not reached) in the 5-mg/kg group, and was 49 days (95% CI, 35-52 days) in the 3-mg/kg group (p = .0006). Dose-dependent asymptomatic proteinuria (39%) and serum creatinine elevation (24%) were the most common adverse events thought to be related to cidofovir. Reversible probenecid reactions including constitutional symptoms and nausea occurred in 65 of 150 (43%) patients. Cidofovir therapy is effective in delaying progression of CMV retinitis that had previously progressed using other anti-CMV therapies.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Antivirais/uso terapêutico , Retinite por Citomegalovirus/tratamento farmacológico , Citosina/análogos & derivados , Organofosfonatos , Compostos Organofosforados/uso terapêutico , Adolescente , Adulto , Antivirais/administração & dosagem , Antivirais/efeitos adversos , Cidofovir , Creatinina/sangue , Citosina/administração & dosagem , Citosina/efeitos adversos , Citosina/uso terapêutico , Progressão da Doença , Quimioterapia Combinada , Feminino , Humanos , Infusões Intravenosas , Pressão Intraocular/efeitos dos fármacos , Rim/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Compostos Organofosforados/administração & dosagem , Compostos Organofosforados/efeitos adversos , Probenecid/efeitos adversos , Probenecid/uso terapêutico , Proteinúria/induzido quimicamente , Recidiva , Fármacos Renais/efeitos adversos , Fármacos Renais/uso terapêutico , Fatores de Risco , Acuidade Visual
7.
J Infect Dis ; 176(6): 1517-23, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9395363

RESUMO

Adefovir dipivoxil is a novel nucleotide analogue with several promising in vitro anti-human immunodeficiency virus (HIV) characteristics. To evaluate the safety and efficacy of adefovir dipivoxil monotherapy, a randomized, double-blind, placebo-controlled study was initiated involving 72 subjects with moderately advanced HIV disease. Subjects were randomly assigned in a 2:1 ratio to receive adefovir dipivoxil or placebo as a once-daily oral dose for 6 weeks, followed by 6 weeks of open-label adefovir dipivoxil. Two dose levels were studied (125 mg and 250 mg). Adefovir dipivoxil was determined to be safe and well-tolerated when administered for 12 weeks. At week 6, changes in absolute CD4 T cell levels and HIV-1 RNA levels were significantly greater with adefovir dipivoxil than with placebo. These effects were sustained through 12 weeks of treatment. As determined by standard RNA sequencing techniques, only 1 of the 24 subjects who received adefovir dipivoxil (125 mg/day) developed any genotypic change from baseline.


Assuntos
Adenina/análogos & derivados , Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , HIV-1 , Organofosfonatos , Adenina/administração & dosagem , Adenina/efeitos adversos , Adenina/uso terapêutico , Administração Oral , Adulto , Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/efeitos adversos , Contagem de Linfócito CD4 , Carnitina/sangue , Citomegalovirus/efeitos dos fármacos , Citomegalovirus/genética , Infecções por Citomegalovirus/virologia , DNA Viral/análise , DNA Viral/genética , Método Duplo-Cego , Feminino , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , Humanos , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Mutação , Reação em Cadeia da Polimerase , RNA Viral/análise , RNA Viral/sangue , RNA Viral/genética , Sêmen/virologia , Análise de Sequência de RNA , Subpopulações de Linfócitos T/imunologia
8.
J Infect Dis ; 176(4): 892-8, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9333146

RESUMO

The safety and efficacy of cidofovir gel for treatment of acyclovir-unresponsive herpes simplex virus infections in AIDS patients was evaluated in a randomized, double-blind, multicenter trial. Cidofovir (0.3% or 1%) or placebo gel was applied once daily for 5 days. Ten of 20 cidofovir-treated and none of 10 placebo-treated patients had complete healing or >50% decreased area (P = .008); 30% of cidofovir-treated patients versus 0 placebo recipients had complete healing (P = .031). Viral shedding ceased in 13 (87%) of 15 cidofovir-treated and 0 of 9 placebo-treated patients (P = .00004). For cidofovir-treated patients, median time to complete or good response was 21 days, and median time to negative viral culture was 2 days (P = .025, P = .0001, respectively). Median lesion area decreases were 58% for cidofovir-treated versus 0 for placebo-treated patients (P = .005), and mean pain score changes were -1.84 versus -0.34 (P = .042). Application site reactions occurred in 25% of cidofovir-treated and 20% of placebo-treated patients; none was dose-limiting. Cidofovir therapy provided significant benefits in lesion healing, virologic effect, and pain reduction.


Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , Aciclovir/uso terapêutico , Antivirais/uso terapêutico , Citosina/análogos & derivados , Herpes Simples/tratamento farmacológico , Organofosfonatos , Compostos Organofosforados/uso terapêutico , Aciclovir/administração & dosagem , Aciclovir/farmacologia , Adulto , Animais , Antivirais/administração & dosagem , Antivirais/efeitos adversos , Células Cultivadas , Chlorocebus aethiops , Cidofovir , Citosina/administração & dosagem , Citosina/efeitos adversos , Citosina/uso terapêutico , Método Duplo-Cego , Resistência Microbiana a Medicamentos , Feminino , Foscarnet/farmacologia , Géis , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mucosa Bucal/virologia , Compostos Organofosforados/administração & dosagem , Compostos Organofosforados/efeitos adversos , Simplexvirus/crescimento & desenvolvimento , Células Vero
9.
J Infect Dis ; 176(2): 406-13, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9237705

RESUMO

A randomized, double-blind, placebo-controlled, dose-escalation study of adefovir dipivoxil, an oral prodrug of adefovir, was conducted in 36 human immunodeficiency virus (HIV)-infected subjects to evaluate its anti-HIV activity, safety, and pharmacokinetics. Subjects received placebo or one of three dosages of adefovir dipivoxil daily for 14 days. Median decreases in serum p24 antigen of 31% (P = .02), 25% (P = .31), and 30% (P = .01) occurred in each drug-treated group, respectively, compared with an increase of 17% in the placebo group. Median decreases in serum HIV RNA of 0.4-0.6 log10 copies/mL occurred in the drug-treated groups (P = .03), compared with no change in the placebo group. Gastrointestinal complaints and reversible liver transaminase elevations were the most frequently noted adverse events. Decreases in serum free carnitine occurred in each drug-treated group during treatment. After 14 days of dosing, adefovir dipivoxil demonstrated anti-HIV activity and was best tolerated at the lowest dosage studied, 125 mg daily.


Assuntos
Adenina/análogos & derivados , Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Organofosfonatos , Adenina/efeitos adversos , Adenina/farmacocinética , Adenina/uso terapêutico , Adulto , Fármacos Anti-HIV/efeitos adversos , Fármacos Anti-HIV/farmacocinética , Carnitina/sangue , Sistema Digestório/efeitos dos fármacos , Método Duplo-Cego , Feminino , Proteína do Núcleo p24 do HIV/sangue , Humanos , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue
10.
Ann Intern Med ; 126(4): 257-63, 1997 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-9036797

RESUMO

BACKGROUND: Cytomegalovirus (CMV) retinitis is the most common intraocular infection in patients with the acquired immunodeficiency syndrome (AIDS). If left untreated, it may lead to progressive destruction of retinal tissue and blindness. Cidofovir is a nucleotide analogue of cytosine that has potent, prolonged in vitro and in vivo activity against herpesviruses, including many CMV isolates that are resistant to ganciclovir and foscarnet. OBJECTIVE: To determine whether intravenous cidofovir delays progression of previously untreated CMV retinitis. DESIGN: Randomized, controlled trial comparing immediate with deferred cidofovir treatment. Patients in the deferred treatment group were eligible to receive cidofovir after progression of CMV retinitis was documented by retinal photography. SETTING: Eight academic medical centers and an independent center that read retinal photographs. PATIENTS: 48 patients with AIDS and previously untreated peripheral CMV retinitis who were randomly assigned to immediate (n = 25) or deferred treatment (n = 23). INTERVENTION: Intravenous cidofovir, 5 mg/kg of body weight, once weekly for 2 weeks and then once every other week. To minimize nephrotoxicity, oral probenecid and intravenous hydration with normal saline were administered with each cidofovir infusion. MEASUREMENTS: Progression of CMV retinitis was assessed by bilateral, full-field retinal photographs that were read by an ophthalmologist who was masked to treatment assignment. Incidence of side effects, changes in visual acuity, effect on CMV shedding in urine and blood, and mortality were also assessed. RESULTS: The median time to progression of CMV retinitis was 22 days (95% CI, 10 to 27 days) in the deferred treatment group and 120 days (CI, 40 to 134 days) in the immediate treatment group (P < 0.001). Neutropenia (15%) and proteinuria (12%), both asymptomatic, were the most common serious adverse events considered to be possibly related to cidofovir. Cidofovir treatment was discontinued in 10 of 41 patients (24%) because of protocol-defined treatment-limiting nephrotoxicity. Transient reactions to probenecid, including mild to moderate constitutional symptoms or nausea, occurred in 23 of 41 patients (56%) and were dose limiting in 3 (7%). CONCLUSIONS: Cidofovir was efficacious in delaying progression of previously untreated CMV retinitis. Treatment was associated with manageable side effects; strict adherence to monitoring of renal function before cidofovir was administered and concomitant administration of probenecid and saline hydration appeared to minimize drug-related nephrotoxicity.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Antivirais/administração & dosagem , Retinite por Citomegalovirus/tratamento farmacológico , Citosina/análogos & derivados , Organofosfonatos , Compostos Organofosforados/administração & dosagem , Infecções Oportunistas Relacionadas com a AIDS/fisiopatologia , Infecções Oportunistas Relacionadas com a AIDS/virologia , Adolescente , Adulto , Antivirais/efeitos adversos , Cidofovir , Retinite por Citomegalovirus/fisiopatologia , Retinite por Citomegalovirus/virologia , Citosina/administração & dosagem , Citosina/efeitos adversos , Progressão da Doença , Feminino , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Compostos Organofosforados/efeitos adversos , Estudos Prospectivos , Acuidade Visual
11.
Antiviral Res ; 29(2-3): 153-61, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8739595

RESUMO

We conducted a single-center, double-blind, placebo-controlled phase I study in HIV-positive subjects to ascertain the safety, tolerance, bioavailability, pharmacokinetics, and maximum tolerated dose of HPMPC (cidofovir). Five subjects were randomized to receive drug and two to receive placebo at each of three dosage tier (1, 3, and 10 mg/kg) with a 2-week washout period doses. Subjects at 1 and 3 mg/kg received single doses of HPMPC by subcutaneous (s.c.) intravenous (i.v.), and oral (p.o.) routes, while subjects at 10 mg/kg received only i.v. and p.o. doses. For subjects already taking zidovudine, zidovudine AUC values are determined before and then with HPMPC administration for each route. The AUC values of HPMPC were dose-proportional. Subcutaneous bioavailability was essentially equivalent to that of the intravenous route, but the development of transient local fibrosis ad the volumes needed for subcutaneous dosing precluded higher subcutaneous dosing than 3 mg/kg. Oral bioavailability was poor, estimated to be less than 5%. Drug elimination was predominantly renal. Nephrotoxicity in one subject was the only serious adverse event observed. This subject had a significant lag period prior to oral absorption and also had the highest AUC values for both HPMPC and zidovudine. We found no consistent effect on zidovudine AUC concomitant HPMPC.


Assuntos
Antivirais/farmacocinética , Citosina/análogos & derivados , Infecções por HIV/tratamento farmacológico , Organofosfonatos , Compostos Organofosforados/farmacocinética , Adolescente , Adulto , Antivirais/efeitos adversos , Disponibilidade Biológica , Cidofovir , Citosina/efeitos adversos , Citosina/farmacocinética , Método Duplo-Cego , Vias de Administração de Medicamentos , Feminino , Infecções por HIV/metabolismo , Infecções por HIV/urina , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Organofosforados/efeitos adversos , Zidovudina/farmacocinética
13.
Antimicrob Agents Chemother ; 39(11): 2401-5, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8585716

RESUMO

The pharmacokinetics and bioavailability of adefovir [9-[2-(phosphonomethoxy)ethyl]adenine] were examined at two dose levels in three phase I/II studies in 28 human immunodeficiency type 1-infected patients. The concentrations of adefovir in serum following the intravenous infusion of 1.0 or 3.0 mg/kg of body weight were dose proportional and declined biexponentially, with an overall mean +/- standard deviation terminal half-life of 1.6 +/- 0.5 h (n = 28). Approximately 90% of the intravenous dose was recovered unchanged in the urine in 12 h, and more than 98% was recovered by 24 h postdosing. The overall mean +/- standard deviation total serum clearance of the drug (223 +/- 53 ml/h/kg; n = 25) approximated the renal clearance (205 +/- 78 ml/h/kg; n = 20), which was significantly higher (P < 0.01) than the baseline creatinine clearance in the same patients (88 +/- 18 ml/h/kg; n = 25). Since adefovir is essentially completely unbound in plasma or serum, these data indicate that active tubular secretion accounted for approximately 60% of the clearance of adefovir. The steady-state volume of distribution of adefovir (418 +/- 76 ml/kg; n = 28) suggests that the drug was distributed in total body water. Repeated daily dosing with adefovir at 1.0 mg/kg/day (n = 8) and 3.0 mg/kg/day (n = 4) for 22 days did not significantly alter the pharmacokinetics of the drug; there was no evidence of accumulation. The oral bioavailability of adefovir at a 3.0-mg/kg dose was < 12% (n = 5) on the basis of the concentrations in serum or 16.4% +/- 16.0% on the basis of urinary recovery. The subcutaneous bioavailability of adefovir at a 3.0-mg/kg dose was 102% +/- 8.3% (n = 5) on the basis of concentrations in serum or 84.8% +/- 28.5% on the basis of urinary recovery. These data are consistent with preclinical observations in various species.


Assuntos
Adenina/análogos & derivados , Antivirais/farmacocinética , Infecções por HIV/metabolismo , HIV-1 , Organofosfonatos , Adenina/administração & dosagem , Adenina/farmacocinética , Administração Oral , Adulto , Antivirais/administração & dosagem , Disponibilidade Biológica , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Meia-Vida , Humanos , Injeções Intravenosas , Injeções Subcutâneas , Masculino , Pessoa de Meia-Idade , Ligação Proteica
14.
Antimicrob Agents Chemother ; 39(6): 1247-52, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7574510

RESUMO

The pharmacokinetics of cidofovir (HPMPC; (S)-1-[3-hydroxy-2-(phosphonylmethoxy)propyl]cytosine) were examined at five dose levels in three phase I/II studies in a total of 42 human immunodeficiency virus-infected patients (with or without asymptomatic cytomegalovirus infection). Levels of cidofovir in serum following intravenous infusion were dose proportional over the dose range of 1.0 to 10.0 mg/kg of body weight and declined biexponentially with an overall mean +/- standard deviation terminal half-life of 2.6 +/- 1.2 h (n = 25). Approximately 90% of the intravenous dose was recovered unchanged in the urine in 24 h. The overall mean +/- standard deviation total clearance of the drug from serum (148 +/- 25 ml/h/kg; n = 25) approximated renal clearance (129 +/- 42 ml/h/kg; n = 25), which was significantly higher (P < 0.001) than the baseline creatinine clearance in the same patients (83 +/- 21 ml/h/kg; n = 12). These data indicate that active tubular secretion played a significant role in the clearance of cidofovir. The steady-state volume of distribution of cidofovir was approximately 500 ml/kg, suggesting that the drug was distributed in total body water. Repeated dosing with cidofovir at 3.0 and 10.0 mg/kg/week did not alter the pharmacokinetics of the drug. Concomitant administration of intravenous cidofovir and oral probenecid to hydrated patients had no significant effect on the pharmacokinetics of cidofovir at a 3.0-mg/kg dose. At higher cidofovir doses, probenecid appeared to block tubular secretion of cidofovir and reduce its renal clearance to a level approaching glomerular filtration.


Assuntos
Antivirais/farmacocinética , Citosina/análogos & derivados , Infecções por HIV/metabolismo , Hospedeiro Imunocomprometido , Organofosfonatos , Compostos Organofosforados/farmacocinética , Infecções Oportunistas Relacionadas com a AIDS/complicações , Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Infecções Oportunistas Relacionadas com a AIDS/metabolismo , Adulto , Antivirais/administração & dosagem , Antivirais/análise , Cidofovir , Infecções por Citomegalovirus/complicações , Infecções por Citomegalovirus/tratamento farmacológico , Infecções por Citomegalovirus/metabolismo , Citosina/administração & dosagem , Citosina/análise , Citosina/farmacocinética , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Rim/metabolismo , Testes de Função Renal , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Compostos Organofosforados/administração & dosagem , Compostos Organofosforados/análise , Probenecid/administração & dosagem , Probenecid/farmacologia
15.
Antimicrob Agents Chemother ; 39(4): 882-6, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7785989

RESUMO

Cidofovir (HPMPC; (S)-1-[3-hydroxy-2-(phosphonylmethoxy)propyl]cytosine) is a nucleotide analog with activity against human cytomegalovirus (CMV). A phase I/II dose escalation trial was conducted with asymptomatic human immunodeficiency virus (HIV)-infected patients with CMV viruria to determine its pharmacokinetics, maximally tolerated dose, and preliminary antiviral activity against CMV. Qualitative CMV blood and urine cultures were monitored weekly to assess anti-CMV activity. Twenty-one HIV-infected persons with CD4 counts from 0 to 389 cells per microliters (median, 39) were enrolled in six dose-ranging groups. The first five groups enrolled four patients each to receive cidofovir infusions either weekly or biweekly for 4 weeks or every 3 weeks for 12 weeks. The sixth group enrolled one patient who received infusions of 5 mg/kg of body weight every other week. Patients receiving 0.5 or 1.5 mg/kg twice weekly experienced no serious toxicity. The first two patients who received 5 mg/kg twice weekly developed glycosuria and 2+ proteinuria. Subsequent patients received concomitant probenecid to attempt to ameliorate renal toxicity. Seventeen patients experienced proteinuria on one or more occasions; 6 of them experienced at least 2+ proteinuria. Four patients did not complete the study as planned because of renal toxicity. Positive CMV urine cultures reverted to negative in 2 of 8 patients receiving doses of < or = 1.5 mg/kg twice weekly and 11 of 13 patients receiving higher doses. Cidofovir has in vivo anti-CMV activity demonstrated by prolonged clearing of CMV viruria, although this observation is tempered by the fact that clearance of viremia could not be demonstrated. The dose-limiting toxicity is renal; however, concurrent administration of probenecid may be protective. The maximally tolerated weekly intravenous dose with probenecid is approximately 5 mg/kg. Efficacy trials with CMV disease will define the therapeutic utility and optimal dosing interval for cidofovir.


Assuntos
Antivirais/uso terapêutico , Infecções por Citomegalovirus/tratamento farmacológico , Citosina/análogos & derivados , Infecções por HIV/tratamento farmacológico , Organofosfonatos , Compostos Organofosforados/uso terapêutico , Adulto , Cidofovir , Citosina/farmacocinética , Citosina/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Organofosforados/farmacocinética , Urina/microbiologia
16.
J Infect Dis ; 170(3): 570-2, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8077713

RESUMO

(S)-1-[3-hydroxy-2-(phosphonylmethoxy)propyl]cytosine (HPMPC) is a nucleotide analogue with potent in vitro and in vivo activity against a broad range of herpesviruses, including acyclovir-resistant herpes simplex virus (HSV). A patient with severe acyclovir-resistant perineal HSV infection received intravenous HPMPC at 5 mg/kg/week, with concomitant oral probenecid and prehydration, and had 95% healing after four infusions. The patient developed a hypersensitivity reaction to probenecid and discontinued HPMPC after the fourth infusion. Recurrence of the perineal lesions 2 weeks later prompted initiation of an oral desensitization program to probenecid and enabled the patient to resume therapy. The lesions again responded to infusions of HPMPC, but the drug was discontinued before complete healing because of transient nephrotoxicity (proteinuria, 2+; creatinine, 1.7 mg/dL). HPMPC is a potent antiviral agent that holds promise as a potential treatment for acyclovir-resistant HSV infection.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Aciclovir/uso terapêutico , Antivirais/uso terapêutico , Citosina/análogos & derivados , Herpes Simples/tratamento farmacológico , Organofosfonatos , Compostos Organofosforados/uso terapêutico , Cidofovir , Citosina/uso terapêutico , Resistência Microbiana a Medicamentos , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Simplexvirus/efeitos dos fármacos
17.
Clin Exp Allergy ; 23(9): 785-90, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10779310

RESUMO

We have recently reported that treatment of patients with severe atopic dermatitis with recombinant interferon-gamma (rIFN-gamma) resulted in clinical improvement as well as a reduction of circulating eosinophils. Since IgE-dependent late phase allergic reactions and eosinophilic infiltration are thought to play an important role in the pathogenesis of asthma, we conducted a two centre randomized double-blind placebo-controlled trial of rIFN-gamma in the treatment of steroid-dependent asthma. Patients were treated with daily subcutaneous injections of either 0.05 mg/m2 rIFN-gamma (n = 9) or placebo (n = 11) for 90 days. All patients completed the study without significant drug toxicity noted. Oral prednisone dose, forced expiratory volume in 1 second (FEV1), peak expiratory flow rates (PEFR) and circulating eosinophil counts were monitored throughout the trial. There was no significant difference between the two treatment groups in per cent reduction from baseline of daily prednisone (P = 0.51). There was also no significant difference between the two treatment groups in per cent change from baseline in FEV1 (P = 0.54) or in PEFR (P = 0.75). Total circulating eosinophil counts decreased by 31% in the rIFN-gamma group and increased by 8.5% in the placebo group (P = 0.09). We conclude that this treatment regimen was not effective in patients with steroid-dependent asthma.


Assuntos
Asma/terapia , Fatores Imunológicos/uso terapêutico , Interferon gama/uso terapêutico , Adolescente , Adulto , Asma/sangue , Asma/tratamento farmacológico , Asma/imunologia , Criança , Terapia Combinada , Método Duplo-Cego , Eosinófilos , Feminino , Volume Expiratório Forçado , Humanos , Imunoglobulina E/imunologia , Fatores Imunológicos/administração & dosagem , Injeções Subcutâneas , Interferon gama/administração & dosagem , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Pico do Fluxo Expiratório , Prednisona/administração & dosagem , Prednisona/uso terapêutico , Proteínas Recombinantes , Falha de Tratamento
18.
J Am Acad Dermatol ; 28(2 Pt 1): 189-97, 1993 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8432915

RESUMO

BACKGROUND: Atopic dermatitis is characterized by immunologic abnormalities including evidence for reduced interferon gamma production. Therapeutic options for treatment of atopic dermatitis are limited and unsatisfactory. Previous open trials have suggested efficacy for recombinant interferon-gamma (rIFN-gamma) in treatment of severe atopic dermatitis. We describe the results of treatment with rIFN-gamma, assessing clinical, immunologic, and laboratory safety parameters in 83 patients with moderate to severe atopic dermatitis. OBJECTIVE: Our purpose was to determine in a randomized, placebo-controlled, double-blind multicenter study the effects of recombinant human interferon gamma therapy in patients with atopic dermatitis. METHODS: Patients received 50 micrograms/m2 rIFN-gamma (n = 40) or placebo (n = 43) by daily subcutaneous injection for 12 weeks. Seventy-eight patients completed the treatment course; two patients receiving rIFN-gamma (one because of constitutional side effects) and three receiving placebo discontinued treatment before completion. Physician and patient overall response evaluations, clinical severity scores, body surface area involvement, and laboratory parameters were monitored throughout the trial. RESULTS: Patients in both treatment groups were similar except that the rIFN-gamma group was older and had a longer disease duration. Forty-five percent of rIFN-gamma-treated patients and 21% of placebo-treated patients achieved greater than 50% improvement in physicians' overall response evaluations (p = 0.016). As estimated by patients, responses also showed significant improvement in the rIFN-gamma group compared with the placebo group (53% vs 21%, p = 0.002). Significant reductions in erythema (p = 0.035) and in excoriations or erosions (p = 0.045) occurred in rIFN-gamma-treated patients. Other atopic symptoms such as conjunctivitis (p < 0.002) were also reduced in the rIFN-gamma group. Occasional headaches, myalgias, or chills occurred in 30% to 60% of rIFN-gamma-treated patients but were effectively prevented by pretreatment acetaminophen and by dosing at bedtime. Grade II granulocytopenia occurred in five rIFN-gamma patients but normalized with continued treatment. Reduction to alternate-day dosing was necessary for six patients in the rIFN-gamma group and two in the placebo group. Seven had mild elevations of hepatic transaminase levels that did not affect therapy. The mean eosinophil count was significantly reduced (p = 0.003), whereas a nonsignificant increase in serum IgE levels occurred in the active treatment group. CONCLUSION: This study demonstrated that rIFN-gamma given by daily subcutaneous injection over a 12-week period was safe, well accepted, and effective in reducing inflammation, clinical symptoms, and eosinophilia in severe atopic dermatitis.


Assuntos
Dermatite Atópica/terapia , Interferon gama/uso terapêutico , Adolescente , Adulto , Fatores Etários , Idoso , Criança , Pré-Escolar , Dermatite Atópica/sangue , Dermatite Atópica/complicações , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Imunoglobulina E/sangue , Imunoglobulina E/efeitos dos fármacos , Injeções Subcutâneas , Interferon gama/administração & dosagem , Interferon gama/efeitos adversos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes , Índice de Gravidade de Doença
19.
Leukemia ; 6(11): 1181-4, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1434801

RESUMO

Fourteen children (ages 2-15 years) with acute leukemia in relapse were treated with daily recombinant interferon gamma for 14 days by subcutaneous injections at fixed dose levels of 0.1, 0.25, 0.5, or 0.75 mg/m2 (1.0, 2.5, 5.0, or 7.5 x 10(6) units/m2) without intrapatient escalation. Patients received a second 14-day course of therapy followed by thrice weekly administration unless there were signs of progressive disease or grade 3 or 4 toxicity. Side effects in the 13 evaluable patients included fever (n = 10), fatigue (9), decreased Karnofsky performance score (8), hypertriglyceridemia (8), myalgia (5), weight loss > 5% (4), elevated liver transaminases (4), and abdominal pain (3). There was only one grade 4 toxicity: one of the six patients at the 0.5 mg/m2 dose level developed reversible acute renal failure. One patient died of gastrointestinal hemorrhage due to disease-related refractory thrombocytopenia. One child had an oncolytic response and two others stable disease for 138 and 148 days. An appropriate dose level for phase II studies in children is 0.5 mg/m2 per day.


Assuntos
Interferon gama/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Interferon gama/efeitos adversos , Interferon gama/farmacocinética , Masculino , Segunda Neoplasia Primária , Proteínas Recombinantes , Recidiva
20.
Arthritis Rheum ; 35(10): 1134-42, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1418004

RESUMO

OBJECTIVE: A phase I/II trial to examine the safety and efficacy of interferon-gamma (IFN gamma) therapy for patients with systemic sclerosis (SSc). METHODS: An 18-week open-label study was performed. Eighteen patients with rapidly progressive SSc were enrolled, 14 of whom completed at least 16 weeks of the study. These 14 patients had a mean age of 40 years and had been diagnosed as having SSc an average of 10.1 months prior to study entry. Recombinant IFN gamma was injected intramuscularly 3 times weekly for 18 weeks. Six patients received a 0.1 mg/m2 dose, while 8 patients received a 0.5 mg/m2 dose. Patients who completed the 18-week trial were offered maintenance therapy at a dose of up to 0.5 mg/m2. The effects of IFN gamma on skin involvement were assessed by 2 methods: 1) evaluation of skin thickness, by scoring 15 zones according to a 0 (normal skin) to 3 (hidebound skin) scale; and 2) determination of the total body surface area involved, by using 2-dimensional body diagrams to indicate areas affected, and then having a second, "blinded," assessor calculate the area score with a planimeter. RESULTS: The mean skin thickness score decreased from a baseline of 25.9 to 19.1 (P < 0.03), and the mean area scores declined from 33.1 to 19.6 (P < 0.02) after 18 weeks of IFN gamma treatment. Ten patients had a > 25% decrease in area score. Five patients had a > or = 70% decrease in area score, and 3 of them have not experienced disease recurrence for 6 to 17 months after discontinuation of IFN gamma. Five patients withdrew before the study ended. Three of these patients developed renal crisis, which may reflect the severity of the SSc in the study group, although an adverse effect of IFN gamma in SSc cannot be excluded. CONCLUSION: IFN gamma was associated with a beneficial effect on the skin involvement in most of this series of patients with rapidly progressive SSc. A placebo-controlled study will be necessary to confirm these results.


Assuntos
Interferon gama/uso terapêutico , Escleroderma Sistêmico/terapia , Adulto , Idoso , Feminino , Seguimentos , Humanos , Interferon gama/administração & dosagem , Interferon gama/efeitos adversos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes , Escleroderma Sistêmico/patologia , Pele/patologia
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