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The contribution of immune activation to accelerated HIV-disease progression in older individuals has not been delineated.Prospective multicenter cohort of older (≥45 years) and younger (18-30 years) HIV-infected adults initiating 192 weeks of antiretroviral therapy (ART). Longitudinal models of CD4 cell restoration examined associations with age-group, thymic volume, immune activation, and viral load.Forty-five older and 45 younger adults (median age 50 and 26 years, respectively) were studied. Older patients had fewer naive CD4 cells (P0.001) and higher HLA-DR/CD38 expression on CD4 (P=0.05) and CD8 cells (P=0.07) than younger patients at any time on ART. The rate of naive and total CD4 cell increase was similar between age groups, but older patients had a faster mean rate of B-cell increase (by +0.7 cells/week; P=0.01), to higher counts than healthy controls after 192 weeks (P=0.003). Naive CD4 increases from baseline were associated with immune activation reductions (as declines from baseline of %CD8 cells expressing HLA-DR/CD38; P0.0001), but these increases were attenuated in older patients, or in those with small thymuses. A 15% reduction in activation was associated with naive gains of 29.9 and 6.2 cells/μl in younger, versus older patients, or with gains of 25.7, 23.4, and 2.1 cells/μl in patients with the largest, intermediate, and smallest thymuses, respectively (P0.01 for interactions between activation reduction and age-group or thymic volume).Older patients had significant B-cell expansion, higher levels of immune activation markers, and significantly attenuated naive CD4 cell gains associated with activation reduction.

Nucleotide mixtures in human immunodeficiency virus type 1 (HIV-1) population sequences reflect sequence diversity. We evaluated gag and pol ambiguous nucleotide frequencies during an analytic treatment interruption (ATI) in an HIV-1 therapeutic vaccine study. The proportion of ambiguous nucleotides was significantly higher at ATI week 16 than at either the time of first detectable viremia (P < 0.001 gag and P = 0.03 reverse transcriptase) or preantiretroviral therapy (P = 0.007 gag). No significant differences were observed in the proportion of ambiguous nucleotides between those receiving vaccine and placebo. Increased HIV diversity during the ATI may represent a potentially higher barrier to success for a therapeutic as compared with a preventative vaccine targeting cell-mediated immunity.

A robust cell-mediated immune response is vital for the resolution of acute infection with human immunodeficiency virus type 1 (HIV-1) and long-term control of disease progression [1–5]. HIV-1 vaccines directed to the cell-mediated immune system could have a role in lowering the plasma HIV-1 RNA set point [6], which may reduce infectivity and delay disease progression. AIDS Clinical Trials Group (ACTG) protocol A5197 was a randomized, placebo-controlled trial to test the effect of a recombinant adenovirus serotype 5 (rAd5) HIV-1 gag therapeutic vaccine on plasma viral load (PVL) in participants undergoing an analytic treatment interruption (ATI) [7]. A total of 110 participants underwent a 16-week ATI after randomization in a 2:1 ratio to receive 3 doses of either vaccine or placebo. Although there was a trend toward a vaccine benefit, this difference failed to reach statistical significance for the prespecified coprimary ATI endpoints (PVL set point: mean of ATI week 12 and 16 PVL and time-averaged area under the curve). However, a secondary analysis based on PVL at ATI week 16 (w16 PVL) found that HIV-1 RNA levels were 0.5 log10 lower in the vaccine arm [7, 8]. The influence of HLA class I alleles on viral evolution, disease progression, and PVL is well known [9–14]. A number of “protective” alleles (HLA B*13, B*27, B*51, B*57, and B*5801) are associated with lower levels of viremia, delayed disease progression, and/or improved outcomes [10, 15–20]. “Unfavorable” HLA alleles associated with accelerated disease progression include the HLA-B*35-Px variants (B*3502, 3503, 3504, or 5301) [21, 22]. In this analysis, we describe the distribution of HLA alleles in ACTG A5197 and explore their impact on the w16 PVL response to a rAd5 HIV-1 gag vaccine. This vaccine induced significant CD4+ and CD8+ HIV-specific T cell responses [7]. In addition to HLA and T cell activation, other factors that may play a role in vaccine effectiveness and viral rebound include pre-antiretroviral therapy (ART) PVLs [23–25], CD4+ T cell counts [23, 24], HLA-associated viral polymorphisms [14], preexisting Ad5 antibody titers [26], and sequence similarity of patient virus to the vaccine [27]. Using a hypothesis-driven approach, we created a multiple linear regression model to identify factors independently correlated with virologic rebound. Because the more robust vaccine effect was not noted until ATI week 16, we focused our analysis on the w16 PVL outcome.

Background HIV-1 specific cellular immunity contributes to control of HIV-1 replication. HIV-1 infected volunteers on antiretroviral therapy received a replication defective Ad5 HIV-1 gag vaccine in a randomized, blinded therapeutic vaccination study.

BACKGROUND Pathogenesis studies show that naive CD4 cells are preferentially depleted in lymphoid tissues during HIV infection, and studies of advanced patients suggest levels of naive CD4 cells in blood correlate to total CD4 cells after starting antiretroviral therapy (ARV). We hypothesized that measuring naive CD4 cells in blood in people at earlier stages of disease would identify those at highest risk for poor CD4 reconstitution who may benefit from earlier initiation of ARV. METHODS AND FINDINGS We identified 348 patients from multiple AIDS Clinical Trials Group studies who were ARV naive, had a CD4 count between 200 and 500 cells per microliter, a measure of pretreatment-naive CD4 percent, and serial follow-up measures of CD4 count and plasma HIV RNA after starting ARV. We used logistic regression to model the ability of naive CD4 percent to predict 100 and 200 CD4 cell increases after 24 months of therapy. After controlling for baseline viral load and demographic variables, baseline naive but not total CD4 cell count strongly predicted CD4 cell increases. Lower baseline naive CD4 percent was associated with greater time spent at lower CD4 T-cell counts after initiating ARV. CONCLUSIONS Measurement of naive CD4 percent in patients can identify those least likely to reconstitute immunity, who may benefit from earlier ARV treatment.

Interleukin 7 (IL-7) is a common gamma chain receptor cytokine implicated in thymopoiesis and in peripheral expansion and survival of T lymphocytes. The safety and activity of recombinant human IL-7 (rhIL-7) administration were therefore examined in HIV-infected persons. In this prospective randomized placebo-controlled study, a single subcutaneous dose of rhIL-7 was well tolerated with biologic activity demonstrable at 3 μg/kg and a maximum tolerated dose of 30 μg/kg. Injection site reactions and transient elevations of liver function tests were the most notable side effects. Transient increases in plasma HIV-RNA levels were observed in 6 of 11 IL-7–treated patients. Recombinant hIL-7 induced CD4 and CD8 T cells to enter cell cycle; cell-cycle entry was also confirmed in antigen-specific CD8 T cells. Administration of rhIL-7 led to transient down-regulation of the IL-7 receptor alpha chain (CD127) in both CD4+ and CD8+ T cells. Single-dose rhIL-7 increased the numbers of circulating CD4+ and CD8+ T cells, predominantly of central memory phenotype. The frequency of CD4+ T cells with a regulatory T-cell phenotype (CD25high CD127low) did not change after rhIL-7 administration. Thus, rhIL-7 has a biologic and toxicity profile suggesting a potential for therapeutic trials in HIV infection and other settings of lymphopenia. This clinical trial has been registered at http://www.clinicaltrials.gov under NCT0099671.

Initiation of combination antiretroviral therapy (ART) results in higher total CD4 cell counts, a surrogate for immune reconstitution. Whether the baseline CD4 cell count affects reconstitution of immune cell subsets has not been well characterized.Using data from 978 patients (621 with comprehensive immunological assessments) from the AIDS [Acquired Immunodeficiency Syndrome] Clinical Trials Group protocol 384, a randomized trial of initial ART, we compared reconstitution of CD4(+), CD4(+) naive and memory, CD4(+) activation, CD8(+), CD8(+) activation, B, and natural killer cells among patients in different baseline CD4(+) strata. Reference ranges for T cell populations in control patients negative for human immunodeficiency virus (HIV) infection were calculated using data from AIDS Clinical Trials Group protocol A5113.Patients in the lower baseline CD4(+) strata did not achieve total CD4(+) cell counts similar to those of patients in the higher strata during 144 weeks of ART, although CD4(+) cell count increases were similar. Ratios of CD4(+) naive-memory cell counts and CD4(+):CD8(+) cell counts remained significantly reduced in patients with lower baseline CD4(+) cell counts (or=350 cells/mm(3)). These immune imbalances were most notable for those initiating ART with a baseline CD4(+) cell countor=200 cells/mm(3), even after adjustment for baseline plasma HIV RNA levels.After nearly 3 years of ART, T cell subsets in patients with baseline CD4(+) cell counts350 cells/mm(3) achieved or approached the reference range those of control individuals without HIV infection. In contrast, patients who began ART withor=350 CD4(+) cells/mm(3) generally did not regain normal CD4(+) naive-memory cell ratios. These results support current guidelines to start ART at a threshold of 350 cells/mm(3) and suggest that there may be immunological benefits associated with initiating therapy at even higher CD4(+) cell counts.

The aim of this study was to optimize the ability to detect cytomegalovirus (CMV)-specfic cell-mediated immunity (CMI) in human immunodeficiency virus (HIV)-infected individuals by comparing different assays (the lymphocyte proliferation assay [LPA] and assays for gamma interferon [IFN-γ] and interleukin-2 [IL-2] production) and CMV antigenic preparations. Thresholds discriminating positive from negative CMI results were developed with specimens from 36 CMV-seropositive and 21 CMV-seronegative healthy individuals. The analysis showed that the CMI elicited by any of the four CMV whole lysates tested in this study tended to be more robust and sensitive than the responses to the subunit antigens gB and pp65. LPA and inducible IFN-γ but not IL-2 were highly sensitive measures of CMV-specific CMI in HIV-infected and -uninfected individuals. The ability to detect CMV-specific LPA or IFN-γ responses in HIV-infected individuals significantly increased with higher CD4 cell numbers. Nevertheless, the proportion of HIV-infected subjects with CD4 counts of ≥500 cells/μl who had a detectable CMV-specific CMI remained significantly lower than that of healthy adults. The ability to detect CMV-specific CMI in HIV-infected individuals decreased with higher levels of HIV replication, with discriminative thresholds of 10 3 to 10 4 HIV RNA copies/ml of plasma, for LPA or inducible IFN-γ production elicited by different antigens. The LPA responses obtained with CMV whole lysate and phytohemagglutinin were significantly correlated in HIV-infected subjects but not uninfected controls, indicating a novel characteristic of the CMI defect caused by HIV. The intrasubject variabilities of the CMV-specific CMI were similar in HIV-infected and -uninfected individuals. These data show that LPA and the inducible IFN-γ production elicited by CMV whole lysates may be used to assess modifications of the immune competency of HIV-infected individuals.

Background. The ability to control human immunodeficiency virus (HIV) replication in vivo in the absence of antiretroviral therapy (ART) is a measure of the efficiency of antiviral immunity. In a study of patients with chronic, ART-suppressed HIV infection, AIDS Clinical Trials Group 5068 investigated the effects of immunization with an exogenous HIV vaccine and pulse exposure to the subject’s unique viral epitopes, by means of structured treatment interruptions (STIs), on the dynamics of viral rebound during a subsequent analytical treatment interruption (ATI). Methods. Ninety-seven subjects receiving stable ART with an HIV-1 RNA load !50 copies/mL and CD4 + T lymphocyte count 1400 cells/mm 3 were randomized to undergo continued ART, STIs, ALVAC-HIV vCP1452 immunization, or STIs and ALVAC-HIV vCP1452 immunization. Results. Subjects in the 2 STI arms had a significantly longer median doubling time in the period of the initial rise of viral load, a significantly lower median peak viral load, a significantly lower median end-of-ATI viral load set point, and a greater proportion of subjects with an end-of-ATI viral load set point !1000 copies/mL, compared with the subjects in the 2 arms without STIs. With an immunization schedule of 3 sets of 3 weekly injections, ALVAC-HIV vCP1452 did not affect viral load measures. Conclusions. In this randomized, controlled study of intermittent STI as a therapeutic autoimmunization strategy, evidence of enhanced immunologic control of HIV replication was demonstrated. Although antiretroviral chemotherapy raises CD4 + T

To determine whether markers of T cell activation and maturation are independently predictive of the response to potent antiretroviral therapy, the Immunophenotypic Markers and Antiretroviral Therapy study applied a novel data-sharing strategy across 5 Adult AIDS Clinical Trial Group trials that counted naive and activated CD4 + and CD8 + T cells in 324 subjects. Regression models—adjustment for baseline CD4 cell count, human immunodeficiency virus (HIV) RNA, and study—revealed that high pretreatment CD8 + T cell activation predicted virologic failure ( P = .046). Additional models showed the greatest increase in CD4 + T cell counts in subjects with highest pretreatment naive CD4 + T cell counts ( P < .0001 ), which was enhanced by high CD4 + and low CD8 + T cell activation. Total lymphocyte count also predicted a subsequent CD4 + T cell change. These results document the utility of T cell markers in predicting treatment outcome and their potential value for the study and management of HIV-1 infection.

We compared immune restoration in patients who suppressed human immunodeficiency virus type 1 replication after treatment with a protease inhibitor (PI) plus nevirapine or with 3 nucleoside reverse-transcriptase inhibitors (NRTIs) plus nevirapine. Changes in total and memory CD4 and CD8 cells were similar in the groups, as were decreases in immune activation (e.g., CD38 and HLA-DR) and increases in CD28 expression. Increases in naive CD4 and CD8 cells tended to be greater in the NRTI-treated group, with differences in naive CD4 cells significant at weeks 8 and 12 (P

It is unclear why discordant immunologic and virologic responses occur during therapy for human immunodeficiency virus (HIV) infection. This study examined whether markers of immune activation and naive/ memory lymphocyte subsets at study baseline could predict discordance between HIV type 1 (HIV-1) RNA and CD4 + lymphocyte responses at week 24 of antiretroviral therapy. Ten diverse, prospective antiretroviral studies with 1007 evaluable subjects were included. Subsets of subjects at increased risk for discordance were identified by recursive partitioning. The strongest predictor of more-favorable immunologic than virologic responses was a lower baseline CD4 + lymphocyte count. Weaker predictors in small subsets of subjects were fewer activated CD4 + lymphocytes and fewer CD8 + lymphocytes. Conversely, the strongest predictors of more-favorable virologic than immunologic responses were higher baseline CD4 + lymphocyte count and percentage. Additional predictors in some analyses were higher CD8 + lymphocyte count or percentage and lower HIV-1 RNA concentrations. Baseline markers of immune activation and naive/memory lymphocyte subsets had limited ability to predict subsequent discordance.

Older age is a strong predictor of accelerated human immunodeficiency virus (HIV) disease progression. We investigated the possible immunologic basis of this interaction by comparing older (>/=45 years) and younger (

OBJECTIVES Interleukin (IL)-12 is a cytokine that stimulates T lymphocytes and natural killer cells to generate a Type 1 T-helper lymphocyte immune response. The primary objective of this study was to determine the safety and immunologic activity of repeated recombinant human IL-12 (rhIL-12) dosing in HIV-infected patients over a broad range of the HIV disease spectrum. DESIGN A randomized, placebo-controlled, Phase 1 trial design was chosen to control for the effects of HIV disease alone on safety and immunologic measurements. METHODS HIV-infected patients on antiretroviral therapy received rhIL-12 or placebo twice weekly for 4 weeks. Subjects were monitored for safety and changes in absolute lymphocyte subset number, serum interferon (IFN)gamma and neopterin levels, plasma HIV RNA level, peripheral blood mononuclear cell (PBMC)-inducible IFNgamma responses to mitogen, and PBMC proliferative responses to phytohemagglutinin, tetanus, Candida, Mycobacterium avium complex, streptokinase, and HIV p24 and gp160 antigens. RESULTS rhIL-12 was well tolerated at doses up to 100 ng/kg in subjects enrolled with CD4 cell counts < 50 x 10(6) cells/l and at all doses in subjects with CD4 cell counts of 300 x 10(6)-500 x 10(6) cells/l. rhIL-12 resulted in dose-related increases in serum neopterin (particularly in subjects with baseline CD4 cell counts of 300-500 x 10(6) cells/l) but in no significant changes in other immunologic measurements or plasma HIV RNA levels. CONCLUSIONS rhIL-12 dosed twice weekly at < or = 100 ng/kg was well tolerated in HIV-infected patients and resulted in dose-related increases in serum neopterin (possibly reflecting the effect of some degree of IFNgamma induction). However, there was no evidence of improvement in antigen-specific immune response.

Thalidomide is used to treat human immunodeficiency virus (HIV)-associated conditions, including aphthous ulcers and wasting syndrome. The safety, tolerability, and pharmacokinetics of a formulation of thalidomide with improved bioavailability in HIV-infected persons was examined in a placebo-controlled, dose-escalating phase 1 study. Subjects with CD4 cell counts of 200-500 cells/mm(3) were enrolled and randomized 3:1 in groups of 12 to receive 50, 100, or 150 mg of thalidomide or matching placebo. Two subjects who received 150 mg of drug and 2 subjects assigned placebo experienced dose-limiting toxicity. Concentrations of thalidomide in the blood increased with escalating dose, but the time to maximum concentration and clearance did not differ across dose cohorts. Previous suggestions of autoinduction of drug metabolism were not confirmed by this study. At the doses studied, thalidomide was tolerated well and had linear pharmacokinetics.

Highly active antiretroviral therapy (HAART) of HIV disease is associated with effective virologic control, immune reconstitution, and clinical improvements. This study addresses the potential for improvements in lymphocyte phenotype and virologic responses of HIV-infected persons with extensive experience with dual nucleoside reverse transcriptase (NRTI) treatment and advanced HIV disease after a change to a potent antiretroviral therapy (NRTI + protease inhibitor). The majority of participants achieved virologic success. There was a median rise in CD4+ lymphocytes of 99 cells/mm(3) by 48 weeks, because of an increase in memory CD4+ cells at 4 and 16 weeks, followed by a later increase in naive CD4+ cells between weeks 16 and 48. The proportion of activated, DR+ CD38+ CD8+ lymphocytes decreased during the 48 weeks of follow-up. The immunologic findings (increased memory and naive T cells and reduced activation levels) were significantly improved in participants with persistent suppression of viral replication over the 48 weeks of the study. Baseline HIV RNA copy number was lower (median, 14,784 copies/ml) in persons who responded virologically than in those not suppressing viral replication (median, 49,454 copies/ml). CD4+ cell counts above the median (125/mm(3)) at time 0 for the participants, was the only baseline immunologic marker significantly associated with viral suppression at week 48. Participants older than 40 years of age demonstrated less immunologic recovery. The results of the study show that patients with extensive experience with NRTIs respond both virologically and immunologically during the first 48 weeks of therapy with a potent antiretroviral regimen.

Poor CD4 lymphocyte recovery on antiretroviral therapy (ART) is associated with reduced function of the thymus. Palifermin (keratinocyte growth factor), by providing support to the thymic epithelium, promotes lymphopoiesis in animal models of bone marrow transplantation and graft-versus-host disease.In AIDS Clinical Trials Group A5212, a randomized, double-blind, placebo-controlled study, 99 HIV-infected patients on ART with plasma HIV-1 RNA levels ≤200 copies per milliliter for ≥6 months and CD4 lymphocyte counts200 cells per cubic milliliter were randomized 1:1:1:1 to receive once daily intravenous administration of placebo or 20, 40, or 60 μg/kg of palifermin on 3 consecutive days.The median change in the CD4 T-cell count from baseline to week 12 was not significantly different between the placebo arm [15 (-16, 23) cells/mm] and the 20-μg/kg dose [11 (2, 32) cells/mm], the 40-μg/kg dose [12 (-2, 25) cells/mm], or the 60-μg/kg dose arm [8 (-13, 35) cells/mm] of palifermin. No significant changes were observed in thymus size or in the number of naive T cells or recent thymic emigrants.Palifermin in the doses studied was not effective in improving thymic function and did not raise CD4 lymphocyte counts in HIV-infected patients with low CD4 cell counts despite virologically effective ART.

Thalidomide has increasing clinical benefits, including the healing of aphthous ulcers in patients with HIV. Unfortunately, pharmacological information addressing the pharmacokinetics (PK) of this compound in HIV patients is limited. Concern exists as to whether thalidomide may alter its own metabolism owing to in vitro data previously reported. Furthermore, no information is available defining the relationship between drug exposure and clinical response. This study evaluated the PK and pharmacodynamics (PD) of thalidomide in patients enrolled in AIDS Clinical Trials Group Protocol 251. Study patients had HIV infection and oral aphthous ulcers of at least 2 weeks'duration. Pharmacologic studies were completed in those subjects randomized to receive active thalidomide at a dose of 200 mg daily for the 4-week study period. PK studies involving serial sampling were carried out in 7 subjects following multiple dosing during study weeks 1 and 4. In addition, trough measurements were done in 20 subjects during each of the 4 study weeks to explore the relationship between time-averaged trough values and extent of clinical response. All samples were analyzed using a validated HPLC method, and parameters were determined using noncompartmental PK analysis. Thalidomide oral clearance averaged 0.14 +/- 0.08 and 0.12 +/- 0.05 l/h/kg on weeks 1 and 4 (p = 0.72), while the terminal elimination half-life averaged 5.7 +/- 1.5 and 7.3 +/- 1.7 hours (p = 0.12). The median time-averaged trough value for subjects deemed complete responders was 0.60, while the median value for noncomplete responders was 0.54. Adjusting for baseline CD4 count and initial index ulcer area, no significant effects were observed of increased thalidomide levels on response. In summary, this study provides steady-state PK data in HIV patients managed with thalidomide and suggests negligible effect of chronic dosing on drug clearance (comparing results from weeks 1 and 4). Furthermore, variable trough measurements between patients do not directly influence the effectiveness of thalidomide for oral aphthous ulcers.

Interleukin (IL)-7 is known to up-regulate thymopoietic pathways of T-cell regeneration. Recent work also has shown it to potently enhance thymic-independent peripheral expansion and to restore immunocompetence in athymic T-cell-depleted hosts. We hypothesized that endogenous IL-7 could contribute to the restoration of T-cell homeostasis following T-cell depletion. To analyze this, we evaluated circulating IL-7 levels and lymphocyte subsets in multiple clinical cohorts with T-cell depletion of varying etiologies. In pediatric (n = 41) and adult (n = 51) human immunodeficiency virus-infected CD4-depleted patients, there were strong inverse correlations between IL-7 levels and CD4 counts (r = -0.77, P

Hypericin is a natural derivative of the common St. Johns wort plant,Hypericum perforatum. It has in vitro activity against several viruses, including bovine diarrhea virus, a pestivirus with structural similarities to hepatitis C virus (HCV). We conducted a phase I dose escalation study to determine the safety and antiviral activity of hypericin in patients with chronic HCV infection. The first 12 patients received an 8-week course of 0.05 mg of hypericin per kg of body weight orally once a day; 7 patients received an 8-week course of 0.10 mg/kg orally once a day. At the end of the 8-week period of treatment, no subject had a change of plasma HCV RNA level of more than 1.0 log10. Five of 12 subjects receiving the 0.05-mg/kg/day dosing schedule and 6 of 7 subjects receiving the 0.10-mg/kg/day dosing schedule developed phototoxic reactions. No other serious adverse events associated with hypericin use occurred. The pharmacokinetic data revealed a long elimination half-life (mean values of 36.1 and 33.8 h, respectively, for the doses of 0.05 and 0.1 mg/kg) and mean area under the curve determinations of 1.5 and 3.1 μg/ml × hr, respectively. In sum, hypericin given orally in doses of 0.05 and 0.10 mg/kg/d caused considerable phototoxicity and had no detectable anti-HCV activity in patients with chronic HCV infection.

A single-platform technology that uses an internal bead standard and three-color flow cytometry to determine CD4 and CD8 absolute counts was evaluated for reproducibility and agreement. Values obtained using TruCount absolute-count tubes were compared to those obtained using a two-color predicate methodology. Sixty specimens from human immunodeficiency virus type 1-infected donors were shipped to five laboratories. Each site also analyzed replicates of 14 human immunodeficiency virus type 1-infected local specimens at 6 h and again at 24 h. The interlaboratory variability was significantly less with TruCount (median difference in percent coefficient of variation [%CV] between the two methods was −8% and −3% for CD4 and CD8, respectively) than with the predicate method. Intralaboratory variability was smaller, with a median difference in %CV of −1% for both CD4 and CD8 with 6-h samples and −2% and −3% for CD4 and CD8, respectively, with 24-h samples. Use of TruCount for shipped samples resulted in a median CD4 count change of 7 cells (50th estimated percentile) when all laboratories and CD4 strata were combined. For on-site samples, the median CD4 count change was 10 CD4 cells for 6-h samples and 2 CD4 cells for 24-h samples. Individual site biases occurred in both directions and cancelled each other when the data were combined for all laboratories. Thus, the combined data showed a smaller change in median CD4 count than what may have occurred at an individual site. In summary, the use of TruCount decreased both the inter- and intralaboratory variability in determining absolute CD4 and CD8 counts.

New analytic methods that permit absolute CD4 and CD8 T-cell determinations to be performed entirely on the flow cytometer have the potential for improving assay precision and accuracy. In a multisite trial, we compared two different single-platform assay methods with a predicate two-color assay in which the absolute lymphocyte count was derived by conventional hematology. A two-color method employing lymphocyte light scatter gating and Beckman Coulter Flow-Count fluorospheres for absolute counting produced within-laboratory precision equivalent to that of the two-color predicate method, as measured by coefficient of variation of replicate measurements. The fully automated Beckman Coulter tetraONE System four-color assay employing CD45 lymphocyte gating, automated analysis, and absolute counting by fluorospheres resulted in a small but significant improvement in the within-laboratory precision of CD4 and CD8 cell counts and percentages suggesting that the CD45 lymphocyte gating and automated analysis might have contributed to the improved performance. Both the two-color method employing Flow-Count fluorospheres and the four-color tetraONE System provided significant and substantial improvements in between-laboratory precision of absolute counts. In some laboratories, absolute counts obtained by the single-platform methods showed small but consistent differences relative to the predicate method. Comparison of each laboratory's absolute counts with the five-laboratory median value suggested that these differences resulted from a bias in the absolute lymphocyte count obtained from the hematology instrument in some laboratories. These results demonstrate the potential for single-platform assay methods to improve within-laboratory and between-laboratory precision of CD4 and CD8 T-cell determinations compared with conventional assay methods.

Human immunodeficiency virus (HIV) type 1-infected persons with newly diagnosed Mycobacterium avium complex (MAC) bacteremia were enrolled in an 8-week study to determine whether treatment of MAC infection is associated with decreases in plasma tumor necrosis factor (TNF)-alpha levels. Blood specimens were obtained for quantitative MAC cultures and to determine plasma levels of HIV RNA, TNF-alpha, and other proinflammatory cytokines. MAC levels decreased by 1.75 log at week 4 (P=.008) and by 2.48 log at week 8 (P=.001). Plasma TNF-alpha decreased by 0.15 log at week 4 (P=.042) and by 0. 40 log at week 8 (P=.027). Plasma interleukin (IL)-6 decreased by 0. 56 log at week 8 (P=.039). There were nonsignificant trends (P

The effect of baseline drug resistance mutations on response to zidovudine, lamivudine, and ritonavir was evaluated in zidovudine-experienced persons infected with human immunodeficiency virus type 1 (HIV-1). Presence of the K70R mutation was associated with significantly higher plasma HIV-1 RNA levels at baseline. However, presence of resistance mutations did not affect the increase in plasma HIV-1 RNA during a 5-week drug washout, nor was there any effect on first-phase virus decay rates after initiation of therapy or on the probability of having plasma HIV-1 RNA levels !100 copies/mL at week 48. Polymorphisms at protease codons 10, 36, and 71 were associated with significantly faster second-phase decay rates. Suppression of plasma HIV-1 RNA despite presence of zidovudine resistance mutations implies that the presence of these mutations does not preclude a durable response to treatment with a potent 3-drug regimen.

The effects of 1 year of zidovudine, lamivudine, and ritonavir treatment on immune reconstitution were evaluated in 34 human immunodeficiency virus (HIV)-infected individuals. After 48 weeks of therapy, 20 (59%) subjects had

Human immunodeficiency virus (HIV) infection is associated with progressive loss of circulating CD4 + lymphocytes. Treatment with highly active antiretroviral therapy (HAART) has led to increases in CD4 + T lymphocytes of naive (CD45RA + 62L + ) and memory (CD45R0 + RA - ) phenotypes. Thymic computerized tomography scans were obtained on 30 individuals with HIV disease to investigate the role of the thymus in cellular restoration after 48 weeks of HAART. Individuals with abundant thymic tissue had higher naive CD4 + T lymphocyte counts at weeks 2-24 after therapy than individuals with minimal thymic tissue. Individuals with abundant thymic tissue had significantly larger increases in naive CD4 + cells during the first 4 weeks of therapy. These individuals were also more likely to experience viral rebound despite comparable initial declines in plasma HIV-1 RNA. These findings suggest that there is a complex relationship among the thymus, viral replication, and lymphocyte restoration after application of HAART in HIV disease.

OBJECTIVES To ascertain if immunization results in the restoration of responses to recall antigens, in the development of responses to presumed neoantigens, and to identify the virologic and immunologic correlates of these responses in persons with HIV-1 infection. DESIGN AND SETTING Open-label study carried out at three university-affiliated AIDS Clinical Trials Units in the United States. SUBJECTS AND METHODS Thirty-one subjects participating in AIDS Clinical Trials Group Protocol 375 who had received zidovudine, lamivudine, and ritonavir for at least 48 weeks. Subjects were immunized with tetanus toxoid (TT) at entry and with inactivated hepatitis A vaccine (hep A) and keyhole limpet hemocyanin (KLH) at entry and 6 weeks. The development of antibody, lymphocyte proliferative assay (LPA), and delayed-type hypersensitivity (DTH) responses after immunization were monitored. RESULTS The LPA and DTH responses to TT improved in 57 and 68% of participants, respectively; 73 and 65% developed enhanced LPA and DTH responses to KLH. Forty-eight percent of patients developed a four-fold increase in antibody concentration to tetanus. Seventy-three percent of patients without detectable hepatitis A antibodies at baseline developed antibodies after immunization. Eighty-three percent of patients experienced at least a four-fold rise in KLH antibody concentration. Immune activation and viral load predicted poor recall responses and the number of memory CD4+ T-cells predicted good responses to recall antigens. Naive CD4+ T-cell numbers, decrease in viral load, increases in CD4+ and CD28+ cells, and decreases in immune activation were associated with responses to presumed neoantigens. CONCLUSIONS Most HIV-infected patients treated with potent combination antiretrovirals develop responses to recall and presumed neoantigens after immunization. Functional immune restoration in response to immunization is related to control of viral replication, decreased immune activation as well as to both quantitative and qualitative restoration of circulating T- lymphocyte subpopulations.

Background In patients with advanced human immunodeficiency virus (HIV) infection, aphthous ulceration of the mouth and oropharynx can become extensive and debilitating. Preliminary reports suggest that thalidomide may promote the healing of oral aphthous ulcers. Methods We performed a double-blind, randomized, placebo-controlled study of thalidomide as therapy for oral aphthous ulcers in HIV-infected patients. The patients received a four-week course of either 200 mg of thalidomide or placebo orally once per day. They were evaluated weekly for the condition of the ulcers, their quality of life, and evidence of toxicity. Assays were performed for plasma tumor necrosis factor α (TNF-α), soluble TNF-α receptors, and HIV RNA. Results Sixteen of 29 patients in the thalidomide group (55 percent) had complete healing of their aphthous ulcers after four weeks, as compared with only 2 of 28 patients in the placebo group (7 percent; odds ratio, 15; 95 percent confidence interval after adjustment for group sequenti...

Objective: To examine the DNA content of circulating lymphocytes obtained from HIV-1-infected persons and to explore the effects of antiretroviral therapy on these indices. Design: Cross-sectional analysis and 48-week open label treatment trial (AIDS Clinical Trials Group Protocol 315) of zidovudine, lamivudine and ritonavir. Methods: Peripheral blood lymphocytes were obtained from HIV-1-infected patients and healthy controls and after 48 h of in vitro cultivation were stained with propidium iodide and analyzed for DNA content by flow cytometry. Results: HIV-1-infected patients had more hypodiploid cells (19%), fewer G 0 -G 1 phase cells (70%) and more S phase cells (10%) than did healthy controls (8%, 85% and 5% respectively; P = 0.002). Patients with sustained suppression of plasma HIV-1 RNA levels after antiretroviral therapy had only modest improvements in these indices. In contrast, patients who failed to suppress plasma HIV-1 RNA levels had decreases in G 0 -G 1 cells to 54% (P = 0.032) and increases in S phase cells to 24% (P = 0.055). Plasma HIV-1 RNA levels and the percentage of S phase cells were correlated (r, 0.23; P = 0.047). In patients failing antiretroviral therapy, there was an inverse correlation between the percentage of G 0 -G 1 cells and expression of the activation antigens CD38 and HLA-DR on CD4 cells (r, -0.409; P = 0.016) and CD8 cells (r, -0.363; P = 0.035). Conclusions: Lymphocytes obtained from HIV-1-infected patients display perturbations in DNA content after brief cultivation in vitro reflective of immune activation in vivo. The marginal improvement in these indices after 'successful' suppression of HIV-1 replication suggests that even low levels of HIV-1 replication are sufficient to induce immune activation and perturbations in DNA content.

Changes in mean telomeric terminal restriction fragment (TRF) length were examined as a marker for cellular replicative history in HIV-1-infected individuals after institution of anti-retroviral therapy (ART). Increases in mean T cell TRF lengths were observed in most patients following therapy; however, the contribution of individual T cell subsets was complex. An elongation of CD8+ T cell TRF was nearly uniformly observed while changes in mean TRF length in CD4+ T cells were heterogeneous as, despite potent suppression of viral replication, CD4 cell telomeres recovered in some patients, yet continued to decline in others. Increases in CD8 cell TRF correlated with decreased memory cells, suggesting a negative selection in the periphery for CD8 cells with extensive replicative history. In contrast, increases in CD4+ T cell TRF length correlated with increases in naive cell subsets, suggesting that the CD4+ T cell TRF increase may reflect a thymic contribution in some patients. These are the first increases in somatic cell telomere length in a population of cells observed in vivo, and the findings are compatible with therapy-induced reconstitution of the lymphoid compartment with cells having a more extensive replicative potential. These findings further distinguish lymphocytes from other somatic cell populations where only decreases in TRF over time have been noted. Thus, institution of ART in persons with moderately advanced HIV-1 disease reveals distinct population dynamics of CD4 and CD8 T cell subsets and also shows that the lymphocyte replicative history is dynamic.

Biphasic plasma viral decays were modeled in 48 patients treated with ritonavir, zidovudine, and lamivudine. Estimated first- and second-phase decay rates were d 1 as 0.47/day and d 2 as 0.04/day. Interpatient differences in both decay rates were significant. The d 1 was directly correlated with baseline CD4 + , CD4 + CD28 + , and CD8 + CD28 + T lymphocyte counts (P< .05) and inversely correlated with baseline virus load (P =.044) and the magnitude of CD4 + and CD8 + T lymphocyte recovery (P

Measures of immune function have become increasingly important as endpoints in AIDS clinical trials, with respect to both modulation and reconstitution of immunity by experimental therapies. Measurement of immune function in this setting requires the development of robust analytic approaches suitable for the clinical laboratory. Experiments were performed to evaluate the suitability of using cultured heparinized (“whole”) blood for induction of tumor necrosis factor alpha (TNF-α) and gamma interferon (IFN-γ), two cytokines critical in AIDS pathogenesis. TNF-α expression ranged from 229 to 769 pg/ml in lipopolysaccharide (LPS)-stimulated cultures and was not detected in unstimulated cultures. IFN-γ expression ranged from 0 to 112,000 pg/ml in phytohemagglutinin A (PHA)-stimulated cultures and from 0 to 789 pg/ml in antigen-stimulated cultures. The mean coefficient of variation observed in three weekly determinations was 0.47 for TNF-α and ranged from 0.12 to 1.73 for IFN-γ. These values indicate that sample sizes of 8, 24, and 29 subjects would be sufficient to detect twofold changes in LPS-induced TNF-α and in PHA- and antigen-induced IFN-γ, respectively, if two baseline and two treatment determinations were obtained, and if the interpatient variability of changes in true levels from baseline to follow-up is negligible compared to the variability in the three weekly measurements. Measurement of LPS-induced TNF-α and mitogen- or antigen-induced IFN-γ can be performed simply and reproducibly in human immunodeficiency virus-infected persons by the whole-blood culture method. Further studies are warranted to determine the effect of overnight shipping on assay reproducibility and to determine the extent to which responses can be reliably detected in subjects with low CD4 cell numbers.

Human immunodeficiency virus (HIV)-1 infection is associated with progressive cell-mediated immune deficiency and abnormal immune activation. Although highly active antiretroviral therapy regimens can increase circulating CD4 T lymphocyte counts and decrease the risk of opportunistic complications, the effects of these treatments on immune reconstitution are not well understood. In 44 persons with moderately advanced HIV-1 infection, after 12 weeks of treatment with zidovudine, lamivudine, and ritonavir, plasma HIV-1 RNA fell a median of 2.3 logs (P < .0001). Circulating numbers of naive and memory CD4 T lymphocytes (P < .001), naive CD8 T lymphocytes (P < .004), and B lymphocytes (P < .001) increased. Improved lymphocyte proliferation to certain antigens and a tendency to improvement in delayed-type hypersensitivity also were seen. Dysregulated immune activation was partially corrected by this regimen; however, the perturbed expression of T cell receptor V regions in the CD4 and CD8 T lymphocyte populations was not significantly affected. Ongoing studies will ascertain if longer durations of virus suppression will permit more complete immune restoration.

BACKGROUND In patients with advanced human immunodeficiency virus (HIV) infection, aphthous ulceration of the mouth and oropharynx can become extensive and debilitating. Preliminary reports suggest that thalidomide may promote the healing of oral aphthous ulcers. METHODS We performed a double-blind, randomized, placebo-controlled study of thalidomide as therapy for oral aphthous ulcers in HIV-infected patients. The patients received a four-week course of either 200 mg of thalidomide or placebo orally once per day. They were evaluated weekly for the condition of the ulcers, their quality of life, and evidence of toxicity. Assays were performed for plasma tumor necrosis factor alpha (TNF-alpha), soluble TNF-alpha receptors, and HIV RNA. RESULTS Sixteen of 29 patients in the thalidomide group (55 percent) had complete healing of their aphthous ulcers after four weeks, as compared with only 2 of 28 patients in the placebo group (7 percent; odds ratio, 15; 95 percent confidence interval after adjustment for group sequential testing, 1.8 to 499; unadjusted P

Tumor necrosis factor-alpha (TNF) may activate human immunodeficiency virus (HIV), antagonize zidovudine activity, and contribute to AIDS wasting syndrome. Pentoxifylline decreases TNF production. In cell culture, pentoxifylline decreases HIV replication and gene expression. Since an AIDS Clinical Trial Group study suggested that pentoxifylline (400 mg thrice daily) is safe in AIDS patients and decreases TNF mRNA levels in peripheral blood mononuclear cells (PBMC), a second cohort received 800 mg thrice daily for 8 weeks. During treatment, the median decrease in TNF production by PBMC cultured with 0.1 microgram/mL lipopolysaccharide (LPS) was 40%. The median change in TNF mRNA was a 34% decrease. Pentoxifylline did not affect HIV levels as detected by quantitative microculture or serum p24 antigen measurements, nor did it alter zidovudine pharmacokinetics. The most common toxicity was gastrointestinal. Pentoxifylline at dosages of less than thrice-daily 800 mg is well tolerated and may decrease TNF mRNA levels and LPS-induced TNF production.

Background: In the placebo-controlled trial ACTG A5197, a trend favoring viral suppression was seen in the HIV-1-infected subjects who received a recombinant Ad5 HIV-1 gag vaccine. Objective: To identify individuals with initial viral suppression (plasma HIV-1 RNA set point ,3.0 log10 copies/ml) during the analytic treatment interruption (ATI) and evaluate the durability and correlates of virologic control and characteristics of HIV sequence evolution. Methods: HIV-1 gag and pol RNA were amplified and sequenced from plasma obtained during the ATI. Immune responses were measured by flow cytometric analysis and intracellular cytokine expression assays. Characteristics of those with and without initial viral suppression were compared using the Wilcoxon rank sum and Fisher’s exact tests. Results: Eleven out of 104 participants (10.6%) were classified as initial virologic suppressors, nine of whom had received the vaccine. Initial virologic suppressors had significantly less CD4+ cell decline by ATI week 16 as compared to non-suppressors (median 7 CD4+ cell gain vs. 247 CD4+ cell loss, P=0.04). However, of the ten initial virologic suppressors with a pVL at ATI week 49, only three maintained pVL ,3.0 log10 copies/ml. HIV-1 Gag-specific CD4+ interferon-c responses were not associated with initial virologic suppression and no evidence of vaccine-driven HIV sequence evolution was detected. Participants with initial virologic suppression were found to have a lower percentage of CD4+ CTLA-4+ cells prior to treatment interruption, but a greater proportion of HIV-1 Gag-reactive CD4+ TNF-a+ cells expressing either CTLA-4 or PD-1. Conclusions: Among individuals participating in a rAd5 therapeutic HIV-1 gag vaccine trial, initial viral suppression was found in a subset of patients, but this response was not sustained. The association between CTLA-4 and PD-1 expression on CD4+ T cells and virologic outcome warrants further study in trials of other therapeutic vaccines in development. Trial Registration: ClinicalTrials.gov NCT00080106

This article summarizes research in statistical methodology contained in a doctoral thesis by John G. Spritzler. A new statistical method is developed for comparing two response rates in a randomized clinical trial, taking into account two common problems. First, how can the trial be analyzed at multiple interim analysis times while still limiting the probability of falsely declaring a treatment difference when there is, in fact, none? Second, how can unbiased interim analyses be done which use all of the available information, if the time, referred to as “lag time,” between when a patient enrolls in the trial and when his or her response status is reported to the statistical center varies randomly from patient to patient, in an unknown manner?The first question is addressed by well-known methods of doing what are referred to as “group sequential” tests. The second question requires the new “lag adjusted” methodology presented in this article. The nature of these two problems in the randomized clinical tr...

The enhanced-sensitivity Trofile assay (TF-ES; Monogram Biosciences) was used to retest coreceptor tropism samples from 4 different cohorts of HIV-1–infected patients. Nine percent to 26% of patients with CCR5-tropic virus by the original Trofile assay had CXCR4-using virus by TF-ES. Lower CD4 cell counts were associated with CXCR4-using virus in all cohorts.

The advent of highly active antiretroviral therapy in the treatment of HIV disease has substantially extended the lifespan of individuals infected with HIV resulting in a growing population of older HIV-infected individuals. The efficacy and safety of antiretroviral agents in the population are important concerns. There have been relatively few studies assessing antiretroviral pharmacokinetics in older patients. Thirty-seven subjects aged 18-30 years and 40 subjects aged 45-79 years, naive to antiretroviral therapy, received lopinavir/ritonavir (400/100) bid, emtricitibine 200 mg qd, and stavudine 40 mg bid. Trough lopinavir concentrations were available for 44 subjects, collected at 24, 36, and 96 weeks. At week 24, older age was associated with higher lopinavir trough concentrations, and a trend was observed toward older age being associated with higher lopinavir trough concentrations when all time points were evaluated. In the young cohort, among subjects with two or more measurements, there was a trend toward increasing intrasubject trough lopinavir concentrations over time. Using a nonlinear, mixed-effects population pharmacokinetic model, age was negatively associated with lopinavir clearance after adjusting for adherence. Adherence was assessed by patient self-reports; older patients missed fewer doses than younger patients (p = 0.02). No difference in grade 3-4 toxicities was observed between the two age group. Older patients have higher trough lopinavir concentrations and likely decreased lopinavir clearance. Age-related changes in the pharmacokinetics of antiretroviral drugs may be of increasing importance as the HIV-infected population ages and as older individuals comprise an increasing proportion of new diagnoses.

The commonly used two-sample tests of equal area-under-the-curve (AUC), where AUC is based on the linear trapezoidal rule, may have poor properties when observations are missing, even if they are missing completely at random (MCAR). We propose two tests: one that has good properties when data are MCAR and another that has good properties when the data are missing at random (MAR), provided that the pattern of missingness is monotonic. In addition, we discuss other non-parametric tests of hypotheses that are similar, but not identical, to the hypothesis of equal AUCs, but that often have better statistical properties than do AUC tests and may be more scientifically appropriate for many settings.

T-regulatory cell (T-reg) frequency is increased in HIV infection and with aging. We evaluated the effect of age on total, memory and naive T-reg percentages in untreated HIV infection. Older HIV(+) subjects had a total T-reg percent that is 2.8% (p=0.02) higher than among younger HIV(+), older HIV(-) and younger HIV(-) subjects. In HIV(+) subjects, the total T-reg percentage is inversely correlated with the lymphocyte proliferative responses to tetanus (r=-0.45, p=0.002) and Candida (r=-0.43, p=0.003) antigens. Similar correlations were seen between memory T-reg percentages and the lymphocyte proliferative response to tetanus and Candida in HIV(+) subjects. T-reg percentages did not correlate consistently with markers of immune activation. T-reg percentages are increased in the older HIV(+) population and may play a role in the accelerated disease progression seen in older HIV-infected persons.

Objective To assess the effect of baseline- and treatment-related factors on immunologic recovery after initiation of antiretroviral therapy (ART). Methods Nine hundred eighty antiretroviral-naive HIV-1+ subjects were randomized to start stavudine/didanosine or zidovudine/lamivudine with nelfinavir, efavirenz, or both nelfinavir and efavirenz. Results Greater CD4 cell recovery was associated with age of 40 years or younger, female sex, higher baseline naive/memory CD4 cell ratio, higher baseline virus load (VL), and virologic suppression (VS). Most subjects who maintained an undetectable VL had a substantial increase in CD4 cell count, but 13% of the subjects did not, even after 3 years of VS. Persistent T-cell activation was associated with lower CD4 cell recovery, even in subjects who achieved VS. Initial treatment assignment did not affect total CD4 cell recovery, naive/memory CD4 cell reconstitution, or decline in T-cell activation. In addition to CD4 cell recovery, B-cell counts rose substantially after ART initiation. Conclusions In this large randomized trial, younger age, female sex, higher naive/memory CD4 cell ratio, higher baseline VL, and VS were associated with greater CD4 cell increase, whereas persistent T-cell activation was associated with impaired CD4 cell recovery after ART initiation. Initial treatment assignment did not affect CD4 cell reconstitution.

A simple framework for assessing and reporting data availability in an ongoing clinical trial is described. Protocol requirements, visit schedules and data availability are combined into a simple report to track the progress of a study.

Background. We have attempted to identify factors associated with T cell reconstitution in response to highly active antiretroviral therapy. Methods. In a prospective, multicenter cohort study, we compared clinical, immune, and viral responses to an initial antiretroviral regimen in older (≥45 years old) versus younger (18-30 years old) human immunodeficiency virus type 1-infected subjects. Multivariable linear-regression models identified independent factors associated with changes in T cell counts. Results. Older subjects had smaller increases in naive T cells but greater T cell receptor-excision circle DNA content after 48 weeks, despite similar virologic responses and comparable reductions in immune activation. Changes in T cell counts were associated with plasma interleukin (IL)-7 levels in subjects with low thymic scores, whereas first-phase T cell increases (perhaps mediated by redistribution to the circulation of tissue-associated lymphocytes) were associated with reductions in immune activation in subjects with high thymic scores. Reductions in immune activation were associated with reductions in spontaneous lymphocyte apoptosis. Conclusions. Distinct processes may underlie T cell restoration, according to estimated thymic volumes. IL-7-mediated peripheral expansion may drive T cell restoration in persons with low thymic volume, whereas therapy-associated reversal of immune reactivation may drive T cell losses and their restoration in persons with larger thymic volume.

Background. CD4 + T lymphocyte (CD4) counts and plasma human immunodeficiency virus (HIV) type 1 RNA concentrations predict clinical outcome in HIV-1 infection. Our objective was to assess the independent prognostic value for disease progression of soluble markers of immune system activation. Methods. This retrospective marker-validation study utilized previously obtained clinical and laboratory data, including CD4 + cell counts, and made use of stored frozen serum samples to assay for levels of β 2 -microglobulin, neopterin, endogenous interferon, triglycerides, interleukin-6, soluble tumor necrosis factor-a receptor II, and HIV-1 RNA, and to determine HIV genotypic reverse-transcriptase inhibitor resistance. The 152 patients who participated in this study represented a subsample of participants in AIDS Clinical Trials Group (ACTG) 116B/ 117, a randomized trial that demonstrated the clinical benefit of didanosine over zidovudine monotherapy in persons with advanced HIV-1 infection. Marker data were analyzed in relation to protocol-defined clinical disease progression, using Cox proportional hazards models. Results. The median duration of follow-up was 344 days. Elevated baseline values for neopterin (P = .0009), endogenous interferon (P =.00039) and interleukin-6 (P =.0007) were each associated with greater subsequent risk of clinical disease progression. In a head-to-head comparison that was adjusted for CD4 + cell count (P =.0165) and HIV -1 RNA level (P =.1220), we found that elevated values for neopterin (P =.0002) and, to a lesser extent, endogenous interferon (P =.0053) were the strongest predictors of increased risk of clinical disease progression 6 months later. Conclusions. Soluble markers of immune activation add prognostic information to CD4 counts and viral load for risk of disease progression in advanced HIV-1 infection. The robust performance of neopterin, an inexpensive and reliably measured serum marker, supports its potential suitability for patient monitoring, particularly in resource-limited settings.

ACTG 266 was designed as a randomized study to evaluate two doses of the human monoclonal antibody directed against CMV gH (MSL-109) versus placebo, each in combination with standard antiviral therapy for the treatment of newly diagnosed Cytomegalovirus (CMV) retinitis in AIDS patients. A total of 82 subjects were enrolled and received either placebo (n = 28), or MSL-109 at 15 mg (n = 26) or 60 mg (n = 28) every 2 weeks until disease progression was diagnosed. The primary endpoint, disease progression, was determined by masked reading of retinal photographs taken every 4 weeks read by a single investigator. The median time to progression was 8.0, 8.3, and 12.1 weeks in the placebo, MSL-109 15 mg and MSL-109 60 mg cohorts, respectively (P = 0.087, placebo versus 60 mg cohort). There were 22 deaths during the study period (9, 9, and 4 in the placebo, MSL-109 15 mg and MSL-109 60 mg cohorts, respectively (P = 0.0058, placebo versus 60 mg cohort)). MSL-109 was well tolerated with no significant adverse events attributable to study medication. The unexplained survival advantage in the higher dose cohort was discordant with the findings of the parallel Studies of Ocular Complications of AIDS Research Group (SOCA)-Monoclonal Anti-CMV Retinitis Trial (MACRT), which was prematurely halted because of increased mortality in subjects treated with high-dose MSL-109, recognizing that A266 enrolled subjects with newly diagnosed, whereas the MACRT enrolled subjects with relapsed, CMV retinitis.

Background Studies have reported that plasma human immunodeficiency virus type 1 (HIV-1) RNA levels and CD4+ lymphocyte counts in HIV-infected patients improved after treatment with granulocyte-macrophage colony-stimulating factor (GM-CSF). Methods In AIDS Clinical Trials Group Protocol 5041, 116 patients were enrolled in a double-blind, randomized, placebo-controlled clinical trial of 16 weeks of 250 microg of GM-CSF administered subcutaneously 3 times/week, followed by open-label treatment for an additional 32 weeks. Patients had stable baseline plasma HIV-1 RNA levels of > or =1500 copies/mL and received constant antiretroviral regimens through at least the first 16 weeks of the study. Results After 16 weeks, the GM-CSF group tended to have greater, though clinically insignificant, increases in plasma HIV-1 RNA levels, compared with the placebo group (median change, +0.048 vs. -0.103 log copies/mL; P=.036, in a post hoc analysis). There were trends toward progressive modest increases in CD4+ lymphocyte counts with GM-CSF treatment at 16 weeks (median change, +14 vs. -6 cells/mm3; P=.06) and beyond. Conclusions GM-CSF does not have an antiviral effect in patients with ongoing HIV replication but may increase CD4+ lymphocyte counts.

Adult Clinical Trials Group Study 349 examined the immunology, virology, and safety of 40 mg/d prednisone as an adjunct to antiretroviral therapy in 24 HIV-infected subjects with >200 CD4+ T cells/mm in a randomized placebo-controlled trial. After 8 weeks, median lymphocyte and CD4+ cell numbers increased >40% above baseline values (p =.08). No effect was observed on markers of cell activation or apoptosis, although the proportion of CD28+ CD8+ T cells increased (p =.006). Prednisone inhibited monocyte TNFalpha production without affecting T-cell responses to antigens or mitogens. Two subjects assigned to prednisone were subsequently found to have asymptomatic osteonecrosis of the hip. Many questions remain regarding the role of activation-induced sequestration and apoptosis as causes of progressive CD4+ T-cell loss in AIDS. The potential role of corticosteroids as tools to examine this question will be limited by concerns regarding their toxicity; however, further studies of other agents to limit cellular activation in AIDS are warranted.

To ascertain whether CD4(+) lymphocyte increases induced by interleukin (IL)-2 enhanced in vivo immune responses, 38 human immunodeficiency virus (HIV)-infected patients who had received highly active antiretroviral therapy (HAART) or HAART and IL-2 for at least 60 weeks were immunized with tetanus toxoid, inactivated glycoprotein 120-depleted HIV-1, and hepatitis A and B vaccines. Despite dramatic increases in CD4(+) lymphocyte counts, IL-2 did not enhance immunization responses.