Kinetics of the changes of lymphocyte subsets defined by cytokine production at single cell level during highly active antiretroviral therapy for HIV-1 infection.
(25/7501)
The effects of highly active antiretroviral therapy on cytokine imbalances associated with HIV-1 infection have not been characterized. Using single cell analysis by flow cytometry, we show that a significant recovery in the frequency of IL-2-producing cells was only observed in patients with a sustained control of viral replication and that the overexpanded CD8 T cell population of CD28- IFN-gamma + cells was not significantly reduced after 1 yr of effective therapy. Moreover, a detrimental role of IL-4 is suggested by the association between an enhanced proportion of IL-4-producing cells within the CD4 and particularly the CD8 subset and viral load rebound. Finally, the kinetics of changes of cell subsets assessed for simultaneous production of different cytokines supports the view that cell reconstitution during highly active antiretroviral therapy is initially due to redistribution of terminally differentiated cells, followed by peripheral expansion of less differentiated ones and a late progressive increase of the proportion of functionally defined naive/memory precursor lymphocytes. These data bring new support for the role of cytokine imbalances in AIDS pathogenesis and may be relevant for the definition of immunointervention targets. (+info)
Hodgkin's disease in 35 patients with HIV infection: an experience with epirubicin, bleomycin, vinblastine and prednisone chemotherapy in combination with antiretroviral therapy and primary use of G-CSF.
(26/7501)
BACKGROUND: The optimal therapeutic approach for patients with Hodgkin's disease and human immunodeficiency virus infection (HD-HIV) is unknown. In an attempt to improve the results previously obtained with EBV (epirubicin, bleomycin and vinblastine) without G-CSF (Cancer 1994; 73: 437-44), in January 1993 we started a trial using chemotherapy (CT) consisting of EBV plus prednisone (EBVP), concomitant antiretroviral therapy (zidovudine, AZT or dideoxinosyne, DDI), and G-CSF. PATIENTS AND METHODS: Up to August, 1997, 35 (30 M/5 F) consecutive previously untreated patients (median age 34, range 21-53 years) with HD-HIV were enrolled in the European Intergroup Study HD-HIV. Their median performance status was 1 (range 1-3). At diagnosis of HD, 26% of the patients had AIDS, 90% had B symptoms at HD presentation and 83% had advanced-stage HD. Patients received E 70 mg/m2 i.v. on day 1, B 10 mg/m2 i.v. on day 1, V 6 mg/m2 i.v. on day 1 and P 40 mg/m2 p.o. from day 1 to day 5 (EBVP). Courses were repeated every 21 days for six cycles. AZT (250 mg x 2/day), or DDI (200 or 300 mg x 2/day) if AZT had been previously used, were given orally from the beginning of CT. G-CSF was given at the dose of 5 mcg/kg/day s.c. from day 6 to day 20 in all cycles. RESULTS: An overall response rate of 91% was observed. There were 74% complete responses (CR) and 17% partial responses (PR). Toxicity was moderate, with grade 3-4 leukopenia and thrombocytopenia in 10 (32%) and three (10%) patients, respectively. The median number of administered cycles was 6 (range 3-6). Twenty-three of 35 patients received AZT and nine patients received DDI. Three (8%) patients had opportunistic infections (OI) during or immediately after CT. The median CD4+ cell count was 219/mm3 (6-812) at HD diagnosis and 220/mm3 (2-619) after the end of combined therapy, and these numbers remained unchanged. Ten of 26 (38%) patients who achieved CR relapsed. Twenty-three patients died of HD progression alone or in association with OI, being the cause of death in 48% and 9% of patients respectively. The median survival was 16 months, with a survival rate of 32% and a disease-free survival of 53% at 36 months. CONCLUSIONS: The combined antineoplastic and antiretroviral treatment is feasible, but HD in HIV setting is associated with a more adverse prognosis than in the general population. Although the CR rate obtained was satisfactory, the relapse rate was high. Furthermore, comparison of the results of our two consecutive prospective studies demonstrated no overall improvement in the current trial with respect to the CR rate and survival. (+info)
Characterization of intestinal disease associated with human immunodeficiency virus infection and response to antiretroviral therapy.
(27/7501)
Combination antiretroviral therapies suppress human immunodeficiency virus (HIV) in peripheral blood, but the effect in gastrointestinal mucosa is uncertain. The occurrence of pathogen-negative diarrhea led to speculation that local HIV infection is etiologic. Mucosal cellular reservoirs for HIV were documented by use of several techniques. Correlations were found among gastrointestinal symptoms, histopathologic findings, cytokine expression, lymphoid apoptosis, and HIV RNA and protein expression in rectal mucosa. Disproportionate depletion of mucosal CD4+ lymphocytes also was found. The short-term effects of antiretroviral therapies were examined to test the hypothesis that these changes are directly related to mucosal HIV infection. Therapy was associated with decreased symptoms, with comparable drops in peripheral blood and mucosal HIV RNA contents, and by increases in blood and mucosal CD4+ lymphocyte contents. In addition, the number of apoptotic cells also declined during therapy. These results suggest that HIV plays a direct role in producing intestinal dysfunction. (+info)
The mode of delivery and the risk of vertical transmission of human immunodeficiency virus type 1--a meta-analysis of 15 prospective cohort studies. The International Perinatal HIV Group.
(28/7501)
BACKGROUND: To evaluate the relation between elective cesarean section and vertical transmission of human immunodeficiency virus type 1 (HIV-1), we performed a meta-analysis using data on individual patients from 15 prospective cohort studies. METHODS: North American and European studies of at least 100 mother-child pairs were included in the meta-analysis. Uniform definitions of modes of delivery were used. Elective cesarean sections were defined as those performed before onset of labor and rupture of membranes. Multivariate logistic-regression analysis was used to adjust for other factors known to be associated with vertical transmission. RESULTS: The primary analysis included data on 8533 mother-child pairs. After adjustment for receipt of antiretroviral therapy, maternal stage of disease, and infant birth weight, the likelihood of vertical transmission of HIV-1 was decreased by approximately 50 percent with elective cesarean section, as compared with other modes of delivery (adjusted odds ratio, 0.43; 95 percent confidence interval, 0.33 to 0.56). The results were similar when the study population was limited to those with rupture of membranes shortly before delivery. The likelihood of transmission was reduced by approximately 87 percent with both elective cesarean section and receipt of antiretroviral therapy during the prenatal, intrapartum, and neonatal periods, as compared with other modes of delivery and the absence of therapy (adjusted odds ratio, 0.13; 95 percent confidence interval, 0.09 to 0.19). Among mother-child pairs receiving antiretroviral therapy during the prenatal, intrapartum, and neonatal periods, rates of vertical transmission were 2.0 percent among the 196 mothers who underwent elective cesarean section and 7.3 percent among the 1255 mothers with other modes of delivery. CONCLUSIONS: The results of this meta-analysis suggest that elective cesarean section reduces the risk of transmission of HIV-1 from mother to child independently of the effects of treatment with zidovudine. (+info)
Improved survival among HIV-infected patients after initiation of triple-drug antiretroviral regimens.
(29/7501)
BACKGROUND: The efficacy of triple-drug antiretroviral regimens in the treatment of patients infected with HIV has been established in several randomized clinical trials. However, the effectiveness of these new regimens in patient populations outside clinical trials remain unproven. This study compared mortality and AIDS-free survival among HIV-infected patients in British Columbia who were treated with double- and triple-drug regimens. METHODS: The authors used a prospective, population-based cohort design to study a population of HIV-positive men and women 18 years or older for whom antiretroviral therapy was first prescribed between Oct. 1, 1994, and Dec. 31, 1996; all patients were from British Columbia. Rates of progression from the initiation of antiretroviral therapy to death or to diagnosis of primary AIDS were determined for patients who initially received an ERA-II regimen (2 nucleoside analogue reverse transcriptase inhibitors [NRTIs] including lamivudine or stavudine, or both) and for those who initially received an ERA-III regimen (triple-drug regimen consisting of 2 NRTIs and a protease inhibitor [indinavir, ritonavir or saquinavir] or a non-NRTI [nevirapine]). RESULTS: A total of 500 men and women (312 receiving an ERA-III regimen and 188 an ERA-III regimen) were eligible. Patients in the ERA-III group survived significantly longer than those in the ERA-II group. As of Dec. 31, 1997, 40 patients had died (35 in the ERA-II group and 5 in the ERA-III group), for a crude mortality rate of 8.0%. The cumulative mortality rates at 12 months were 7.4% (95% confidence interval [CI] 5.9% to 8.9%) for patients in the ERA-II group and 1.6% (95% CI 0.7% to 2.5%) for those in the ERA-III group (log rank p = 0.003). The likelihood of death was more than 3 times higher among patients in the ERA-II group (mortality risk ratio 3.82 [95% CI 1.48% to 9.84], p = 0.006). After adjustment for prophylaxis for Pneumocystis carinii pneumonia or Mycobacterium avium infection, AIDS diagnosis, CD4+ cell count, sex and age at initiation of therapy, the likelihood of death among patients in the ERA-II group was 3.21 times higher (95% CI 1.24 to 8.30, p = 0.016) than in the ERA-III group. Cumulative rates of progression to AIDS or death at 12 months were 9.6% (95% CI 7.7% to 11.5%) in the ERA-II group and 3.3% (95% CI 1.8% to 4.8%) in the ERA-III group (log rank p = 0.006). After adjustment for prognostic variables (prophylaxis for P. carinii pneumonia or M. avium infection, CD4+ cell count, sex and age at initiation of treatment), the likelihood of progression to AIDS or death at 12 months among patients in the ERA-II group was 2.37 times higher (95% CI 1.04 to 5.38, p = 0.040) than in the ERA-III group. INTERPRETATION: This population-based cohort study confirms that patients initially treated with a triple-drug antiretroviral regimen comprising 2 NRTIs plus protease inhibitor or a non-NRTI have a lower risk of morbidity and death than patients treated exclusively with 2 NRTIs. (+info)
Pharmacokinetics of beta-L-2',3'-dideoxy-5-fluorocytidine in rhesus monkeys.
(30/7501)
beta-L-2',3'-Dideoxy-5-fluorocytidine (beta-L-FddC), a novel cytidine analog with an unnatural beta-L sugar configuration, has been demonstrated by our group and others to exhibit highly selective in vitro activity against human immunodeficiency virus types 1 and 2 and hepatitis B virus. This encouraging in vitro antiviral activity prompted us to assess its pharmacokinetics in rhesus monkeys. Three monkeys were administered an intravenous dose of [3H] beta-L-FddC at 5 mg/kg of body weight. Following a 3-month washout period, an equivalent oral dose was administered. Plasma and urine samples were collected at various times for up to 24 h after dosing, and drug levels were quantitated by high-pressure liquid chromatography. Pharmacokinetic parameters were obtained on the basis of a two-compartment open model with a first-order elimination from the central compartment. After intravenous administration, the mean peak concentration in plasma (Cmax) was 29.8 +/- 10.5 microM. Total clearance, steady-state volume of distribution, terminal-phase plasma half-life (t1/2 beta), and mean residence time were 0.7 +/- 0.1 liters/h/kg, 1.3 +/- 0.1 liters/kg, 1.8 +/- 0.2 h, and 1.9 +/- 0.2 h, respectively. Approximately 47% +/- 16% of the intravenously administered radioactivity was recovered in the urine as the unchanged drug with no apparent metabolites. beta-L-FddC exhibited a Cmax of 3.2 microM after oral administration, with a time to peak drug concentration of approximately 1.5 h and a t1/2 of 2.2 h. One monkey in the oral administration arm of the study had a significant delay in the absorption of the aqueous administered dose. The absolute bioavailability of orally administered beta-L-FddC ranged from 56 to 66%. (+info)
Pharmacokinetics of oral zidovudine entrapped in biodegradable nanospheres in rabbits.
(31/7501)
The pharmacokinetic profile of oral zidovudine entrapped in a 50:50 polyactide-coglycolide matrix (nanospheres) was compared to those of standard oral and parenteral zidovudine formulations in rabbits. The bioavailability of zidovudine nanospheres at 50 mg/kg of body weight was 76%, and this dose achieved prolonged exposure to zidovudine compared to standard formulations without an increase in the drug's peak concentration. (+info)
Experience with a managed care approach to HIV infection: effectiveness of an interdisciplinary team.
(32/7501)
To evaluate the function and effectiveness of a multidisciplinary team for managing human immunodeficiency virus (HIV) infection, we conducted a follow-up cohort study of HIV-positive patients managed according to a clinical care path at a staff-based health maintenance organization (HMO). The study group consisted of 230 HIV-positive health plan members who received care at the Kaiser Permanente Santa Rosa medical center (KPMC-SRO). In 1994, the comparison group consisted of 4747 HIV-positive health plan members who received care at Kaiser Permanente's 18 other medical centers in northern California. The percentages of acquired immunodeficiency syndrome (AIDS) and HIV-positive patients as determined by CD4+ T-cell counts were similar (P = 0.97). Compared with patients at the other Kaiser Permanente medical centers, KPMC-SRO patients had more visits with nurse practitioners (rate ratio [RR] = 1.72) and nutritionists (RR = 12.3) and fewer visits with primary care physicians (RR = 0.82). More HIV-positive members at KPMC-SRO received social workers' services (27% at KPMC-SRO vs 6% for patients at the other Kaiser Permanente medical centers) and fewer used emergency services (RR = 0.92) and psychiatric services (RR = .89). At KPMC-SRO, the mean number of days that AIDS patients spent in the hospital decreased from 7.8 (1991) to 2.01 (1994). Hospital admissions were fewer (AIDS patients, RR = 0.67; HIV-positive patients without AIDS, RR = 0.45), and length of stay was briefer, compared with patients at the other Kaiser Permanente Medical Centers. The mean cost of HIV-related drugs for patients seen at KPMC-SRO ($2343 per infected member) was lower than that for patients seen elsewhere in the region ($3289 per infected member). These results suggest that in an HMO setting, managed care provided by a dedicated interdisciplinary team according to a clinical care path can substantially and favorably affect resource use. (+info)