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Background:  We report the first-in-human safety and immunogenicity assessment of a prototype intranasally administered, replication-competent Sendai virus (SeV)-vectored, human immunodeficiency virus type 1 (HIV-1) vaccine., Methods:  Sixty-five HIV-1-uninfected adults in Kenya, Rwanda, and the United Kingdom were assigned to receive 1 of 4 prime-boost regimens (administered at 0 and 4 months, respectively; ratio of vaccine to placebo recipients, 12:4): priming with a lower-dose SeV-Gag given intranasally, followed by boosting with an adenovirus 35-vectored vaccine encoding HIV-1 Gag, reverse transcriptase, integrase, and Nef (Ad35-GRIN) given intramuscularly (S L A); priming with a higher-dose SeV-Gag given intranasally, followed by boosting with Ad35-GRIN given intramuscularly (S H A); priming with Ad35-GRIN given intramuscularly, followed by boosting with a higher-dose SeV-Gag given intranasally (AS H ); and priming and boosting with a higher-dose SeV-Gag given intranasally (S H S H )., Results:  All vaccine regimens were well tolerated. Gag-specific IFN-γ enzyme-linked immunospot-determined response rates and geometric mean responses were higher (96% and 248 spot-forming units, respectively) in groups primed with SeV-Gag and boosted with Ad35-GRIN (S L A and S H A) than those after a single dose of Ad35-GRIN (56% and 54 spot-forming units, respectively) or SeV-Gag (55% and 59 spot-forming units, respectively); responses persisted for ≥8 months after completion of the prime-boost regimen. Functional CD8 + T-cell responses with greater breadth, magnitude, and frequency in a viral inhibition assay were also seen in the S L A and S H A groups after Ad35-GRIN boost, compared with those who received either vaccine alone. SeV-Gag did not boost T-cell counts in the AS H group. In contrast, the highest Gag-specific antibody titers were seen in the AS H group. Mucosal antibody responses were sporadic., Conclusions:  SeV-Gag primed functional, durable HIV-specific T-cell responses and boosted antibody responses. The prime-boost sequence appears to determine which arm of the immune response is stimulated., Clinical Trials Registration:  NCT01705990., (© The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America.)

Background: Few studies consider the incidence of individual AIDS-defining illnesses (ADIs) at higher CD4 counts, relevant on a population level for monitoring and resource allocation., Methods: Individuals from the Collaboration of Observational HIV Epidemiological Research Europe (COHERE) aged ≥14 years with ≥1 CD4 count of ≥200 µL between 1998 and 2010 were included. Incidence rates (per 1000 person-years of follow-up [PYFU]) were calculated for each ADI within different CD4 strata; Poisson regression, using generalized estimating equations and robust standard errors, was used to model rates of ADIs with current CD4 ≥500/µL., Results: A total of 12 135 ADIs occurred at a CD4 count of ≥200 cells/µL among 207 539 persons with 1 154 803 PYFU. Incidence rates declined from 20.5 per 1000 PYFU (95% confidence interval [CI], 20.0-21.1 per 1000 PYFU) with current CD4 200-349 cells/µL to 4.1 per 1000 PYFU (95% CI, 3.6-4.6 per 1000 PYFU) with current CD4 ≥ 1000 cells/µL. Persons with a current CD4 of 500-749 cells/µL had a significantly higher rate of ADIs (adjusted incidence rate ratio [aIRR], 1.20; 95% CI, 1.10-1.32), whereas those with a current CD4 of ≥1000 cells/µL had a similar rate (aIRR, 0.92; 95% CI, .79-1.07), compared to a current CD4 of 750-999 cells/µL. Results were consistent in persons with high or low viral load. Findings were stronger for malignant ADIs (aIRR, 1.52; 95% CI, 1.25-1.86) than for nonmalignant ADIs (aIRR, 1.12; 95% CI, 1.01-1.25), comparing persons with a current CD4 of 500-749 cells/µL to 750-999 cells/µL., Discussion: The incidence of ADIs was higher in individuals with a current CD4 count of 500-749 cells/µL compared to those with a CD4 count of 750-999 cells/µL, but did not decrease further at higher CD4 counts. Results were similar in patients virologically suppressed on combination antiretroviral therapy, suggesting that immune reconstitution is not complete until the CD4 increases to >750 cells/µL.

Background: The immunomodulatory nutritional product NR100157 was developed for human immunodeficiency virus (HIV)-infected individuals. We hypothesized that targeting the compromised gastrointestinal tract of HIV-infected individuals would result in systemic immunological benefits., Methods: In a multicenter, randomized, controlled, double-blind trial, 340 HIV-1-positive adults not on antiretroviral therapy, with CD4(+) T-cell counts <800/µL, were given either NR100157 or an isocaloric and isonitrogenous control for 52 weeks. Primary outcome was CD4(+) T-cell count. Secondary outcomes included plasma viral load (pVL), safety, and tolerability. In a pilot study (n = 20), levels of CD4(+)CD25(+) and CD8(+)CD38(+) activation were measured (n = 20). The trial is registered at the Dutch Trial Register (NTR886) and ISRCTN81868024., Results: At 52 weeks, CD4(+) T-cell decline showed a 40-cell/µL difference (P = .03) in the intention-to-treat population in favor of the immunomodulatory NR100157 (control vs active, -68 ± 15 vs -28 ± 16 cells/µL/year). The change in pVL from baseline was similar between groups (P = .81). In the pilot study, the percentage of CD4(+)CD25(+) was lower in the active group (P < .05) and correlated with changes in CD4(+) T-cell count (r = -0.55, P < .05). The percentage of CD8(+)CD38(+) levels was unaffected., Conclusions: The specific immunonutritional product NR100157 significantly reduces CD4(+) decline in HIV-1-infected individuals, and this is associated with decreased levels of CD4(+)CD25(+). (This nutritional intervention is likely to affect local gut integrity and gut-associated lymphoid tissue homeostasis, which in turn translates positively to systemic effects.) Clinical Trials Registration. ISRCTN81868024.

Objectives: The pharmacokinetic and pharmacodynamic effects of antiretroviral therapy may differ in older compared with younger subjects with HIV infection. We aimed to assess factors associated with plasma antiretroviral drug exposure, including age, within a large HIV-infected cohort undergoing therapeutic drug monitoring (TDM)., Methods: Data from the Liverpool TDM Registry were linked with the UK Collaborative HIV Cohort (CHIC) Study. All TDM of protease inhibitors (PIs) and non-nucleoside reverse transcriptase inhibitors (NNRTIs) was included and in order to account for different antiretroviral drugs the plasma concentrations were standardized by group measurements according to drug, dosing and timing of TDM. Regression modelling was used to evaluate associations of drug exposure with age and clinical parameters, including hepatic transaminase results and time to antiretroviral treatment modification., Results: Data from 3589 TDM samples were available from 2447 subjects. The greatest numbers of plasma concentrations were assessed for lopinavir (22.4%), efavirenz (18.5%), atazanavir (17.0%) and saquinavir (11.6%). As age increased, median standardized NNRTI concentrations remained constant, whereas PI concentrations increased (correlation coefficient 0.04, P = 0.033). In a regression analysis stratified by antiretroviral drug class, standardized plasma concentrations were significantly associated with age for PIs (0.05 increase in standard deviation of drug concentration with each 10 year increase in age, P = 0.044), but not for NNRTIs or other clinical parameters, including hepatic transaminase results or time to antiretroviral treatment modification., Conclusions: With increasing age, statistically significant rises in plasma PI exposure, but not NNRTI exposure, were observed. The clinical relevance of this observation merits further investigation.

Introduction: The CD4 count and CD4 percentage (CD4%) are both strong predictors of clinical disease progression in human immunodeficiency virus (HIV). Although individuals may show discordancy between their CD4 count and CD4%, the clinical relevance of this is unclear., Methods: Discordancy was defined where the CD4% was ≤10th percentile for a selected CD4 count range (referred to as low discordancy), within the central 80% range (concordant), or ≥90th percentile (high discordancy). Regression methods identified factors associated with low and high discordancy in untreated individuals and assessed the impact of discordancy on treatment responses to highly active antiretroviral therapy (HAART)., Results: High discordancy was associated with female sex, low viral load, and white ethnicity; low discordancy was associated with black or nonwhite ethnicity, older age, and injection drug use. Clinical event rates were higher in individuals with high discordancy starting HAART, but there was no association with subsequent HIV progression by 6 months after starting HAART. CD4 count increases remained lower, by 20 cells/mm(3), in individuals with low discordancy, and higher, by 27 cells/mm(3), in those with high discordancy., Conclusions: Overall discrepancies between the CD4/CD4% are small, confirming the use of absolute CD4 counts as a monitoring tool.

Objectives: To assess the pharmacokinetics (PK) of raltegravir and ezetimibe when co-administered to healthy volunteers., Methods: This was a prospective, open-label, crossover study, with subjects randomly assigned to group 1 (raltegravir 400 mg twice daily, raltegravir plus ezetimibe 10 mg once daily, wash-out period, ezetimibe) or group 2 (ezetimibe, raltegravir plus ezetimibe, wash-out period, raltegravir); all phases lasted for 10 days. Steady-state full PK sampling was performed at days 10, 20 and 40. Raltegravir and ezetimibe PK parameters were determined by non-compartmental methods and comparisons in the presence of the potentially interactive drug measured by geometric mean ratio (GMR) and 95% confidence intervals (CIs)., Results: Twenty subjects (10 females) completed the study. Raltegravir PK parameters did not change significantly in the presence of ezetimibe: GMRs (95% CI) were 1.16 (0.89-1.51) for AUC(0-12), 1.13 (0.81-1.58) for maximum plasma concentration (Cmax) and 1.12 (0.72-1.74) for trough concentration (Ctrough). Ezetimibe AUC0-24 and Ctrough were lower in the presence of raltegravir [GMRs (95% CI) were 0.79 (0.68-0.91) for AUC0-24 and 0.78 (0.60-0.99) for Ctrough], while ezetimibe glucuronide Cmax was 40% higher (90% CI 1.17-1.66). There was marked inter-individual variability in the PK of the two drugs, especially during co-administration., Conclusions: There were no significant changes in raltegravir PK parameters with or without ezetimibe. However, in the presence of raltegravir, ezetimibe AUC0-24 and Ctrough were significantly lower (>20%) and ezetimibe glucuronide Cmax was higher. Clinical data to assess the importance of the change in ezetimibe concentrations are warranted.

Objectives: Data suggest that some licensed antiretroviral doses could be reduced. We assessed the safety, tolerability and pharmacokinetics of lopinavir/ritonavir at doses of 400/100, 200/150 and 200/50 mg twice daily in HIV-negative volunteers (http://clinicaltrials.gov/ct2/show/NCT00985543)., Methods: Male and female volunteers were administered lopinavir/ritonavir at doses of 400/100 mg (two lopinavir/ritonavir Meltrex 200/50 mg tablets, Regimen 1), 200/150 mg (one Meltrex tablet, one 100 mg ritonavir capsule, Regimen 2) and 200/50 mg (one Meltrex tablet, Regimen 3). Each dose was given twice daily for 7 days sequentially, separated by a 7 day wash-out period. Lopinavir/ritonavir steady-state pharmacokinetics was assessed over 12 h at the end of each phase (days 7, 21 and 35). Pharmacokinetic parameters were compared using the 400/100 mg twice daily dose as reference, by determining geometric mean ratios (GMRs) and 90% confidence intervals., Results: Twenty-two subjects (eight females) completed the study. Lopinavir AUC(0-12) (ng h/mL), C(max) (ng/mL) and the minimum concentration (C(trough)) (ng/mL) for the 400/100, 200/150 and 200/50 mg twice daily doses, respectively, were as follows: 99,599, 73,603 and 45,146; 11,965, 8939 and 6404; and 5776, 4293 and 1749. Lopinavir pharmacokinetic parameters were significantly lower for Regimens 2 and 3: GMR (90% CI) AUC(0-12), 0.74 (0.65-0.84) and 0.45 (0.40-0.51); C(max), 0.75 (0.66-0.85) and 0.54 (0.40-0.60); and C(trough), 0.74 (0.62-0.89) and 0.30 (0.25-0.36), respectively. All subjects taking the 400/100 and 200/150 mg twice daily doses, and 19 (86%) subjects taking 200/50 mg twice daily had lopinavir concentrations above the suggested minimum effective concentration of 1000 ng/mL., Conclusions: These pharmacokinetic data show that therapeutic plasma concentrations of lopinavir can be achieved with 200/150 mg of lopinavir/ritonavir twice daily (one Meltrex tablet and one 100 mg ritonavir capsule twice daily).

Background: Antiretroviral therapy is complicated by drug interactions and contraindications. Novel regimens are needed., Methods: This open label study randomly assigned treatment-naive, human immunodeficiency virus (HIV)-infected subjects to receive tenofovir-emtricitabine with efavirenz (Arm I), with ritonavir-boosted atazanavir (Arm II), or with zidovudine/abacavir (Arm III). Pair-wise comparisons of differences in time-weighted mean change from baseline plasma HIV-RNA to week 48 formed the primary analysis. Treatment arms were noninferior if the upper limit of the 95% confidence interval (CI) was <0.5 log(10) copies/mL. Secondary objectives included virologic, immunologic and safety end points., Results: The intention-to-treat population comprised 322 patients (Arm I, n = 114; Arm II, n = 105; and Arm III, n = 103). Noninferiority for the primary end point was established. Analysis for superiority showed that Arm III was significantly less potent than Arm I (-0.20 log(10) copies/mL; 95% CI, -0.39 to -0.01 log(10) copies/mL; P = .038). The proportions of patients on each of Arm I (95%) and Arm II (96%) with <200 copies/mL were not different (P = .75), but the percentage of patients in Arm III with <200 copies/mL (82%) was significantly lower (P = .005). CD4+ cell counts did not differ. Serious adverse events were more frequent in Arm III (n = 30) than in Arm I or Arm II (n = 15 for each; P = .062)., Conclusions: A novel quadruple nucleo(t)side combination demonstrated significantly less suppression of HIV replication, compared with the suppression demonstrated by standard antiretroviral therapy regimens, although it did meet the predetermined formal definition of noninferiority. Secondary analyses indicated statistically inferior virologic and safety performance. Efavirenz and ritonavir-boosted atazanavir arms were equivalent in viral suppression and safety.

Background: The protease inhibitors lopinavir and atazanavir are both recommended for treatment of HIV-infected patients. Considerable inter-individual variability in plasma concentration has been observed for both drugs. The aim of this study was to evaluate which demographic factors and concomitant drugs are associated with lopinavir and atazanavir plasma concentration., Methods: Data from the Liverpool TDM (therapeutic drug monitoring) Registry were linked with the UK Collaborative HIV Cohort (CHIC) study. For each patient, the first measurement of lopinavir (twice daily) or atazanavir [once daily, ritonavir boosted (/r) or unboosted] plasma concentration was included. Linear regression was used to evaluate the association of dose, gender, age, weight, ethnicity and concomitant antiretroviral drugs or rifabutin with log-transformed drug concentration, adjusted for time since last intake., Results: Data from 439 patients on lopinavir (69% 400 mg/r, 31% 533 mg/r; 3% concomitant rifabutin) and 313 on atazanavir (60% 300 mg/r, 32% 400 mg/r, 8% 400 mg) were included. Multivariable models revealed the following predictors for lopinavir concentration: weight (11% decrease per additional 10 kg; P = 0.001); dose (25% increase for 533 mg/r; P = 0.024); and rifabutin (116% increase; P < 0.001). For atazanavir the predictors were dose (compared with 300 mg/r: 40% increase for 400 mg/r, 67% decrease for 400 mg; overall P < 0.001) and efavirenz (32% decrease; P = 0.016) but not tenofovir (P = 0.54)., Conclusions: This analysis confirms that efavirenz decreases atazanavir concentrations, and there was a negative association of weight and lopinavir concentrations. The strong impact of rifabutin on lopinavir concentration should be studied further.

Patients with a baseline viral load >100,000 copies/mL receiving abacavir (ABC) as part of the nucleoside-backbone component of their first highly active antiretroviral therapy (HAART) regimen have been reported to have a greater failure rate than those receiving tenofovir (TDF). We analyzed short-term outcomes of the use of HAART combinations that included ABC or TDF. The mean 2-8-week change in viral load was calculated using linear regression. In total, 1136 patients started ABC, and 412 started TDF. After adjustment for baseline viral load and other factors, there was no difference in the change in viral load between the patients who started ABC and those who started TDF (0.03 [95% confidence interval, -0.07 to 0.12]) log copies/mL; P = .59). Furthermore, there was no evidence that this effect differed according to baseline viral load (P = .88 for the interaction between pre-HAART viral load and nucleoside started). Likewise, there was no difference in rates of virological failure between the 2 drugs at 24-48 weeks after starting HAART.

Monocyte-derived dendritic cells (MDDCs) have been used in therapeutic vaccination for cancer. A small number of studies have employed a similar approach to vaccinate human immunodeficiency virus (HIV)-infected individuals. We have thus analyzed the functional properties of MDDCs generated from HIV-infected individuals who either are receiving highly active antiretroviral therapy or are therapy naive. There was no difference in the MDDC phenotype or efficiency of MDDC generation between HIV-infected individuals and healthy control subjects. Despite this, the MDDCs derived from both groups of infected individuals were severely impaired in their ability to stimulate the proliferation of allogeneic T cells. Furthermore, production of interferon-gamma was reduced in T cells stimulated by MDDCs. These functional changes may be at least partly explained by reduced interleukin-12 and increased interleukin-10 secretion on stimulation with lipopolysaccharide and CD40 ligand. Our findings suggest that MDDCs used in therapeutic vaccination of HIV-infected individuals may show reduced potency.

Background: Human immunodeficiency virus (HIV) uses 2 distinct chemokine receptors, CCR5 (R5) or CXCR4 (X4), during entry. Viruses may be R5 tropic, X4 tropic, or dual/mixed (D/M) tropic. R5-tropic virus predominates at high CD4 cell counts, with the number of X4-tropic strains increasing as CD4 cell count decreases., Methods: We investigated the relationship between tropism and decreases in CD4 cell count before antiretroviral therapy initiation, the frequency of clinical events, and responses to antiretroviral therapy in a cohort of treatment-naive patients., Results: Four hundred two treatment-naive patients underwent tropism determination; 326 harbored R5-tropic virus, and 76 harbored X4- or D/M-tropic virus. After adjustment for baseline characteristics, the rate of decrease in CD4 cell count was significantly greater in patients infected with X4- or D/M-tropic virus at 12 months (P=.026). Two hundred twenty-nine individuals infected with R5-tropic virus and 60 individuals infected with X4- or D/M-tropic virus commenced antiretroviral therapy between tropism testing and the time of data analysis. Time to viral suppression and the proportion of patients achieving viral suppression were similar at 6, 12, and 24 months. CD4 cell count increases were similar. Clinical events were significantly more common in the group infected with X4- or D/M-tropic virus. Multivariate analysis demonstrated a relative risk of experiencing a clinical event of 2.56 (95% confidence interval, 1.37-4.76; P=.003) among patients infected with X4- or D/M-tropic virus., Conclusions: The presence of D/M- or X4-tropic virus has a deleterious effect on CD4 cell count decrease and risk of clinical disease. Response to standard antiretroviral therapy is not affected by viral tropism.

The L74V and K65R mutations confer resistance to several nucleoside analogues, and the impact on subsequent regimens is unclear. The risk of developing L74V or K65R mutation in the era of highly active antiretroviral therapy (HAART) was 4.5 and 2.8 cases per 100 person-years, respectively; concomitant receipt of boosted protease inhibitors protected against K65R. High rates of virologic suppression in the presence of either mutation were observed if the next regimen contained at least 2 active agents. If suboptimal HAART was used, patients with K65R experienced significantly higher rates of virologic suppression than did those with L74V (P = .01).

There are limited data on the efficacy of T cell-based assays to detect tuberculosis (TB) antigen-specific responses in immune-deficient human immunodeficiency virus (HIV) patients. The aim of this study is to determine whether TB antigen-specific immune responses can be detected in patients with HIV-1 infection, especially in those with advanced disease (CD4 T cell count < 300 cells/microl). An enzyme-linked immunospot (ELISPOT) assay, which detects interferon (IFN)-gamma secreted by T cells exposed to TB antigens, was used to assess specific immune responses in a prospective study of 201 HIV-1-infected patients with risk factors for TB infection, attending a single HIV unit. The performance of the ELISPOT assay to detect TB antigen-specific immune responses is independent of CD4 T cell counts in HIV-1 patients. The sensitivity and specificity of this assay for the diagnosis of active tuberculosis does not differ significantly from values obtained in immunocompetent subjects. The negative predictive value of the TB ELISPOT test is 98.2%. A positive predictive value of 86% for the diagnosis of active tuberculosis was found when the combined number of early secretory antigen target-6 (ESAT-6) and culture filtrate protein-10 (CFP-10) IFN-gamma spots to CD4 T cell count ratio was > 1.5. TB antigen-specific immune responses can be detected in HIV patients with low CD4 T cell counts using ELISPOT technology in a routine diagnostic laboratory and is a useful test to exclude TB infection in immune-deficient HIV-1 patients. A combination of TB antigen-specific IFN-gamma responses and CD4 T cell counts has the potential to distinguish active tuberculosis from latent infection.

Background: Initiation of antiretroviral therapy during primary human immunodeficiency virus (HIV)-1 infection may confer long-term benefit., Methods: After initiation of zidovudine, lamivudine, abacavir, and amprenavir therapy in patients in the QUEST cohort, predictors of virological outcome, virological and immunological changes, and adverse events were evaluated over 48 weeks., Results: One hundred forty-eight patients started antiretroviral therapy during primary HIV-1 infection with < or =3 bands on Western Blot (median plasma HIV-1 RNA load, 5.4 log copies/mL; median CD4 cell count, 517 cells/mm(3)). By week 48, 36% of patients had stopped treatment or were lost to follow-up. Among the 115 patients receiving follow-up care at week 48 (102 of whom were receiving antiretroviral therapy), the median viral load decrease was -5.4 log copies/mL (interquartile range [IQR], -6.4 to -3.9 log copies/mL), and the median increase in CD4 cell count was 147 cells/mm(3) (IQR, -1 to 283 cells/mm(3)); 84.2% of patients had a viral load < or =50 copies/mL, and 44.7% of patients had a viral load < or =3 copies/mL. The median cell-associated RNA level decreased from 3.4 log copies/million PBMCs (IQR, 2.9-4.1 log copies/million PBMCs) to 0.8 log copies/million PBMCs (IQR, 0.5-1.4 log copies/million PBMCs), and the median cell-associated DNA level decreased from 2.8 log copies/million PBMCs (IQR, 2.4-3.0 log copies/million PBMCs) to 1.6 log copies/million PBMCs (IQR, 1.2-1.9 log copies/million PBMCs); 33.3% of patients had an undetectable RNA level, and 9.5% of patients had an undetectable cell-associated DNA level. The median CD8(+)/CD38(++) T cell count decreased from 459 cells/mm(3) (IQR, 208-974 cells/mm(3)) to 33 cells/mm(3) (IQR, 19-75 cells/mm(3)). Baseline CD8(+)/CD38(++) T cell count and cell-associated DNA level were independent inverse predictors for reaching a viral load < or =3 copies/mL. Eighty-three patients experienced a serious adverse event (median duration of an adverse event, 15 days).Conclusions. Initiation of antiretroviral therapy during primary HIV-1 infection was associated with very significant antiretroviral activity and a decrease in immune activation. Lower baseline CD8(+)/CD38(++) T cell count and cell-associated DNA level were predictive of achieving a viral load < or =3 copies/mL.

Generally physicians have a legal and ethical obligation of keeping confidentiality regarding their communication with patients and it is clear that we all have rights. The application of rights theorem, which usually refers to the recognition of individual human rights, to the deceased offers possible answers to the problematic question of patient confidentiality after death. Philosophical considerations broadly support utilitarian ideals concerning the 'common good'. However, it may be possible to rank rights according to a hierarchy of need and thus preserve individual rights where they do not impinge upon the public's right to protection from harm and the physician's right to tell the truth. This has broad implications for confidentiality, anonymity and health care information in general for patients, their families and healthcare workers. We discuss these issues, with specific reference to an individual case.

Objectives: To examine cellular and plasma concentrations of atazanavir when given in combination with saquinavir/ritonavir in HIV+ patients., Methods: Twelve HIV+ patients were receiving saquinavir/atazanavir/ritonavir 1600/200/100 mg once daily and venous blood samples were taken to determine cellular and plasma concentrations of each protease inhibitor at 2, 6, 12 and 24 h. Peripheral blood mononuclear cells were separated by density gradient centrifugation. The ratio of the cellular AUC0-24/plasma AUC0-24 was calculated to determine cellular drug accumulation. Lymphocyte P-glycoprotein (P-gp), breast cancer resistance protein (BCRP) and multidrug resistance-associated protein (MRP1) expression was determined by flow cytometry. Nine of the patients had previously received a regimen of saquinavir/ritonavir 1600/100 mg; therefore the effect of atazanavir on the cellular and plasma pharmacokinetics of saquinavir and ritonavir was examined., Results: In vivo cellular and plasma determinations of saquinavir, atazanavir and ritonavir gave accumulation ratios of 4.9, 1.2 and 1.7, respectively. There was no relationship between saquinavir, atazanavir or ritonavir accumulation and P-gp, MRP1 or BCRP expression. When comparing pharmacokinetic values in the nine patients receiving saquinavir/ritonavir with and without atazanavir, the median cellular saquinavir AUC0-24 was significantly increased (34.9-117.2 mg.h/L) on addition of atazanavir (P=0.004). The C24 of saquinavir in plasma and cells was significantly higher with atazanavir (plasma C24 0.05 versus 0.14 mg/L with atazanavir; cellular C24 0.61 versus 2.03 mg/L with atazanavir, P=0.02)., Conclusions: The mechanism of differential intracellular protease inhibitor accumulation is unclear. Co-administration of atazanavir caused an increase in both the plasma and cellular exposure (AUC0-24) and C24 of saquinavir but not ritonavir.

From a cohort of 9621 human immunodeficiency virus type 1-infected individuals, we identified 61 patients with primary central nervous system lymphoma (PCL) who had a median survival of 1.3 months. We compared clinicopathologic variables of patients who were treated in the pre-highly active antiretroviral therapy (HAART) and HAART eras and investigated whether exposure to antiretroviral agents with differing cerebrospinal fluid penetrations was associated with risk for PCL. All statistical tests were two-sided. Incidence of PCL was lower in the HAART era (1.2 cases per 1000 patient-years, 95% confidence interval [CI] = 0.8 to 1.9) than in the pre-HAART era (three cases per 1000 years, 95% CI = 2.1 to 4.0; P<.001), and overall survival was longer (median survival = 32 days, range = 5-315 days, versus 48 days, range = 15-1136 days; log rank P = .03). In the HAART era, fewer patients had prior acquired immunodeficiency syndrome-defining illnesses than in the pre-HAART era (64% versus 90%; P = .013), and patients were more likely to have the diagnosis of PCL confirmed histologically or by polymerase chain reaction (77% versus 26%; P<.001). Exposure to specific antiretroviral agents was not associated with risk for PCL.

Immunosuppression induced by the human immunodeficiency virus (HIV-1) increases the risk of death. We measured the influence of immunological and virological factors and the type of highly active anti-retroviral therapy (HAART) on this risk. Adaptive (lymphocyte) and innate (natural killer) immune correlates and maximum HIV viral loads were assessed for association with mortality using univariate and multivariate analyses. The protective effect of HAART regimens, containing protease inhibitors (PI) and/or non-nucleoside reverse transcriptase inhibitors (NNRTI) on mortality were also examined in a prospectively recorded cohort of 9621 HIV-infected individuals. From this entire cohort, 5873 HIV infected individuals (61%) have been followed-up in the HAART era and of these 499 (8.5%) have died. In multivariate analyses, CD4 counts below the 50th centile and CD8 and CD19 counts below the 25th centile were significantly associated with mortality, as was increased age (P < 0.001). Innate immune subset levels had no effect on mortality. A maximum HIV viral load greater than the 75th centile was also associated independently with mortality (P < 0.035). Exposure to either a PI or an NNRTI-containing HAART regimen, or both together, was protective against death compared with no anti-retrovirals (P < 0.001). Effective HAART-induced maintenance of the adaptive immune system (CD4, CD8 and CD19 counts) protects from HIV-related mortality.

Background: Atazanavir, an azadipeptide protease inhibitor (PI) with once daily dosing, a lack of insulin resistance, lipid increase, and gastrointestinal toxicities, is approved in combination with other antiretrovirals for the treatment of patients infected with HIV. Unboosted atazanavir is also used in highly active antiretroviral therapy (HAART) naive patients., Methods: The study prospectively followed up an established cohort of patients who received atazanavir, and for whom one year of follow up data were available., Results: It was found that use of atazanavir in intent to treat and on treatment analyses, maintained and led to virological suppression and increases in CD4 count in both PI naive and experienced patients. Virological failure occurred in 7% of patients and the main toxicity was hyperbilirubinaemia, which led to treatment withdrawal in 2%. Its efficacy and safety profile was similar to that seen in previous randomised studies investigating its use., Conclusions: These data should provide reassurance for clinicians wishing to introduce a new antiretroviral into an established cohort.

Background: Relatively few data are available on the association between the use of specific antiretroviral drugs and the rate of viral rebound in those attaining a viral load (VL) <50 copies/mL while receiving highly active antiretroviral therapy (HAART)., Methods: Patients achieving a VL <50 copies/mL for the first time while receiving HAART were followed until viral rebound (2 consecutive VLs >500 copies/mL). Pre-HAART antiretroviral-naive patients were analyzed separately from those with nucleoside reverse transcriptase inhibitor (NRTI) experience., Results: Of 3565 suppressed antiretroviral-naive patients, 381 experienced viral rebound (rate, 6.26 events/100 person-years of follow-up [pyrs] [95% confidence interval {CI}, 5.63-6.89 events/100 pyrs]). For those receiving efavirenz, the rate was 4.08 (95% CI, 3.16-5.01) events/pyrs. Compared with this, the rebound rate for those receiving indinavir was 1.52 times higher (rate ratio [RR], 1.52 [95% CI, 0.82-2.84]). RRs (95% CIs) for other drugs were: soft-gel saquinavir, 0.54 (0.07-3.97); nelfinavir, 2.44 (1.68-3.54); indinavir/ritonavir, 1.96 (1.02-3.77); saquinavir/ritonavir, 1.12 (0.48-2.61); lopinavir/ritonavir, 1.23 (0.58-2.59); nevirapine, 1.53 (1.11-2.10); and abacavir, 2.03 (1.26-3.25). Of 810 NRTI-exposed patients, 145 experienced viral rebound (rate, 8.29 [95% CI, 6.94-9.64] events/pyrs). For those receiving efavirenz, the rate was 5.25 (95% CI, 3.11-8.30) events/pyrs. Compared with this, the RRs (95% CIs) were: indinavir, 1.75 (0.82-3.73); hard-gel saquinavir, 3.48 (0.36-33.37); nelfinavir, 2.64 (1.37-5.08); indinavir/ritonavir, 0.32 (0.04-2.49); saquinavir/ritonavir, 0.64 (0.23-1.80); nevirapine, 1.65 (0.90-3.02); and abacavir, 1.82 (0.73-4.52)., Conclusions: We must make comparisons of antiretroviral outcomes in observational data with caution; however, our results suggest that, in those with VLs <50 copies/mL, certain drugs may be associated with higher rebound rates than others.

Human immunodeficiency virus type 1 (HIV-1) appears to adversely affect hepatitis C, but whether hepatitis C virus (HCV) has a reciprocal effect on HIV-1 infection remains a point of controversy. In a multivariate analysis of a cohort of 5832 individuals, we found that individuals coinfected with HCV and HIV-1 (prevalence of coinfection, 5.8%) had a CD4+ cell count that decreased at a rate similar to that for individuals infected with HIV-1 alone. However, coinfection was associated with a statistically significant increased likelihood of onset of an acquired immunodeficiency syndromedefining illness or developing a CD4+ cell count of <200 cells/mm3, compared with infection with HIV-1 alone (hazard ratio, 1.52; 95% confidence interval, 1.072.17). Patients who were naive to highly active antiretroviral therapy were significantly less likely to progress to either end point, because of their higher CD4+ cell counts. In conclusion, there was an increased number of adverse events in coinfected individuals, compared with individuals infected with HIV-1 alone.

Background: The CD4 count is a dominant prognostic and predictive factor in HIV infection. This study assessed the utility of the total lymphocyte count (TLC) in place of the CD4 count to predict the development of AIDS defining opportunistic infections (ADOI)., Methods: The Chelsea and Westminster cohort was used to identify those people with a first episode of an ADOI. Corresponding CD4 and TLCs were recorded before diagnosis or at the time of first prescribing prophylaxis; patients without an AIDS defining opportunistic infection were defined as being at "risk" and receiver operating characteristic (ROC) curves were used to display the results of sensitivity and the false positive error rate of total lymphocyte and CD4 count groups., Results: A significant linear correlation was seen between the log(10) CD4 count and log(10) TLC (Pearson's correlation coefficient = 0.70, p<0.001). The finer cut off value for TLC where false positive error rate is minimum and sensitivity maximum was 1500-2000 cells/mm(3). Patients with TLC 1000-1500 cells/mm(3) were estimated to be at 40% increased risk of developing an ADOI. The cut off value for CD4 counts measured 200 cells/mm(3) above which the risk developing an ADOI decreased. Patients with a CD4 count of 150-200 cells/mm(3) were at a 34% increased risk of developing an ADOI. The area under the ROC curve for TLC was 10% lower than that for CD4 count., Conclusions: The TLC is minimally less reliable than the CD4 count as a predictor of ADOIs. In the absence of expensive equipment for CD4 measurement, the TLC is a useful test.

Background: Treatment failure during highly active antiretroviral therapy (HAART) is ultimately common and associated with the development of resistance mutations. Trizivir (zidovudine/lamivudine/abacavir) and tenofovir disoproxil fumarate may improve adherence and enhance virological suppression in individuals who have failed previous regimens., Methods: Individuals were identified who had failed previous HAART and who were then prescribed trizivir and tenofovir. Viral load and genotypic information were obtained to assess virological response., Results: One hundred and twenty-two individuals were identified from a database containing 5883 patients. In a last observation carried forward intention to treat analysis, 34% of individuals achieved an undetectable viral load of <50 copies/mL at 1 year. Of those who were able to remain on treatment for 1 year, 65% achieved undetectability. We observed no effect regarding previous regimens on viral outcome. Accumulation of TAMs (thymidine analogue mutations) was associated with a decrease in the number of patients achieving an undetectable viral load (with <2 TAMs present 38% of patients developed undetectable viral loads, > or =1;2 TAMs 17% undetectable; P = 0.03). Using the mean cell volume as a measure of compliance, those with higher values were more likely to achieve a viral load <50 copies/mL (P = 0.04). A beneficial effect on cholesterol was noted regardless of virological outcome., Conclusions: In compliant heavily pre-treated individuals with less than 2 TAMs, salvage therapy with trizivir and tenofovir is associated with suppression of viraemia and an improved lipid profile.

Objectives: The amount of ritonavir needed to enhance saquinavir hard gel (hg) plasma concentrations is unclear. Reduced ritonavir dosing may help to reduce ritonavir-related side effects and costs. This study examined the pharmacokinetics of twice-daily saquinavir-hg (1000 mg) in the presence of ritonavir 100 mg, dosed twice-daily and once-daily on one single occasion., Methods: Eighteen HIV-infected adults taking saquinavir/ritonavir 1000/100 mg twice-daily underwent pharmacokinetic (PK) assessment of saquinavir/ritonavir on day 1 following a morning saquinavir/ritonavir dose. On day 2, PK assessment was repeated when subjects took saquinavir without ritonavir. Drug intake (with a standard meal containing 20 g of fat) was timed on days -1, 1 and 2. Geometric mean ratios (GMR) and 95% confidence intervals (CI) were calculated to assess changes in saquinavir PK parameters., Results: Geometric mean saquinavir AUC(0-12), C(trough), C(max) and elimination half-life on days 1 and 2 were 14 389 and 9590 ng.h/mL, 331 and 234 ng/mL, 2503 and 1893 ng/mL and 2.80 and 2.82 h, respectively. The GMR (95% CI) for these parameters were 0.67 (0.53-0.84), 0.71 (0.48-1.04), 0.76 (0.58-0.98) and 1.01 (0.86-1.18), respectively., Conclusions: Withholding a ritonavir dose significantly reduces overall saquinavir exposure and C(max), but had no impact on the elimination half-life. These data establish the need to administer saquinavir and ritonavir simultaneously.

Background: Evidence from randomized controlled trials supports the use of triple therapy. Research is required on the effectiveness of quadruple therapy in comparison to this and the relative effectiveness of specific highly active antiretroviral therapy (HAART) combinations., Methods: Antiretroviral-naive individuals (n = 53) with an HIV-1 viral load >100 000 copies/mL were randomized to receive three-drug HAART with zidovudine/lamivudine (Combivir) and efavirenz or quadruple therapy with zidovudine/lamivudine/abacavir (Trizivir) and efavirenz (quad regimen). Patients continued on HAART for 48 weeks with regular clinical and immunological assessment. Standard and ultrasensitive (<5 copies/mL) viral load testing was carried out., Results: A DAVG (difference in averages) analysis of the fall in viral load and increase in CD4 count showed no significant differences between regimens. Triple therapy resulted in a -4.17 log change (95% CI, -4.48 to -3.85) and quadruple therapy in a -4.36 log change (95% CI, -4.68 to -4.03) in viral load. For CD4 counts, the triple therapy arm increased by 164 cells/mm(3) (95% CI 112-217) and the quadruple arm by 185 (95% CI, 133-237). In an intent-to-treat analysis, 77% of patients in the triple therapy group reached an undetectable viral load (<50 copies/mL) compared with 84.2% of the quadruple therapy group. For ultrasensitive viral load testing, 23% and 18% of each group, respectively, reached undetectable viral loads. The hazard ratio for attaining a viral load of <5 copies/mL was 0.59 (95% CI, 0.26-1.33) for quadruple versus triple therapy. Three individuals in the triple therapy arm and nine in the quadruple therapy arm discontinued treatment., Conclusions: No differences in any analyses were observed between a standard of care regimen (zidovudine/lamivudine and efavirenz) and the quad regimen (zidovudine/lamivudine/abacavir and efavirenz).

Despite advances in our understanding of tumour immunology there is no therapy of proven survival benefit for advanced melanoma. Nevertheless, disease progression is slow in a small proportion of patients with metastatic melanoma, suggesting a contribution to outcome from host factors. Recent data have indicated the importance of the heat shock protein receptor CD91 in immune responses to, and progression of, infectious disease. Here we investigate the relationship between CD91 expression and outcome in malignancy. Rare melanoma patients were recruited with advanced disease that was progressing unusually slowly. CD91 expression on their monocytes was compared with control patients with more typical rapidly advancing metastatic disease. Th1 and Th2 cytokines, as well as innate and adaptive immune subsets, were also measured in the two groups. A significant increase in median CD91 expression levels was observed in slow progressors (P = 0.006). There were no differences in other immune subset markers or inflammatory cytokines. The ability of CD91 to internalize and cross-present tumour antigens through the major histocompatibility complex class I pathway may maintain CD8-positive cytotoxic T cell responses and contribute to slow progression of advanced melanoma.

Objective: To compare the immunological response to highly active antiretroviral therapy (HAART) in treatment-naive patients with a baseline CD4 count of <200 cells/mm(3)., Design and Methods: We identified treatment-naive human immunodeficiency virus (HIV-1)-infected individuals who had commenced HAART since 1996 and who had a starting CD4 count of <200 cells/mm(3). Immunological success was defined as achieving a CD4 count of >200 cells/mm(3) and treatments were compared using univariate and multivariate Cox's proportional hazards models in order to establish whether protease inhibitor (PI)-based regimens were significantly different to regimens based on non-nucleoside reverse transcriptase inhibitors (NNRTIs). Both regimens utilize a nucleoside analogue (NA) backbone., Results: A total of 599 patients were identified. When the variables were entered into a multivariate analysis, no significant differences between HAART regimens were found. We showed that compared with efavirenz regimens a two NA plus one PI regimen was not significantly less likely to achieve immunological success (adjusted HR: 0.65, 95% CI 0.41-1.03, P=0.07). Two NA and boosted PI (adjusted HR: 1.33, 95% CI 0.81 to 2.16) or two NA and nevirapine (adjusted HR: 0.93, 95% CI 0.67-1.29) regimens were also not significantly different from efavirenz-based regimens, based on the endpoint of immunological success., Conclusion: PI-, boosted PI- and NNRTI-based HAART regimens are not significantly different in achieving increased CD4 counts in individuals who commence therapy with a low CD4 count.

Background: Treatment failure during highly active antiretroviral therapy (HAART) is ultimately common and associated with the development of resistance mutations to both the specific drug in question and cross-resistance to other available treatment options. In heavily pre-treated patients, the recycling of antiretroviral agents that have been utilized previously may, however, be associated with antiviral efficacy. We therefore conducted an investigation into the concept of recycling stavudine (d4T, Zerit) and didanosine (ddI, Videx) with and without hydroxyurea, in the management of heavily pre-treated HIV-1 infected individuals requiring salvage therapy (RESTART)., Methods: We randomized 21 individuals with treatment failure to receive stavudine and didanosine or stavudine, didanosine and hydroxyurea, for 12 weeks prior to optimizing therapy. Viral load, immunological parameters, genotypic information and the virtual phenotypes were obtained at baseline and at the end of the study., Results: Significant decreases in viral loads were observed in both groups during a 12 week study period (P = 0.04), the addition of hydroxyurea conferring no additional benefit. This was not predicted by information from genotypes and virtual phenotypes, and these did not reveal sensitive or specific phenotypic cut-offs for those individuals who responded to recycling., Conclusions: Salvage therapy with didanosine and stavudine can decrease viral loads in heavily pre-treated individuals. Genotypic and virtual phenotype profiles provide little additional information in this setting.

Heat shock proteins interact with antigen-presenting cells through their receptor, CD91, eliciting a cascade of events including maturation, activation and representation of chaperoned foreign peptides with class I molecules on their surface. In turn, this facilitates recognition of non-self leading to induction of a cytotoxic T cell response. The abundance of heat shock proteins in tumours and their presence in virion coats makes them attractive propositions for use in antitumour and antiviral strategies.

Previous studies have shown that human natural killer (NK) cells are lost from the periphery and are functionally suppressed during HIV-1 infection, and that the administration of highly active antiretroviral therapy (HAART) results in a recovery of NK cell numbers in HIV-1-infected individuals. However, despite this recovery, interleukin (IL)-2 + IL-12-driven interferon (IFN)-gamma production by NK cells has been shown to remain suppressed after HAART. Here we show that the innate immune factor IL-15 in combination with IL-12 is also unable to recover NK cell IFN-gamma production in HAART-treated individuals. Furthermore, we also demonstrate an imbalance in the distribution of CD56loCD16hi and CD56hiCD16- NK subsets after successful HAART, CD56hiCD16- cells being reduced substantially in HIV-1 patients on HAART. Treatment of patients with combined human growth hormone and antiretroviral therapy resulted in further enhancement in the absolute numbers and the proportion of NK cells in some individuals in the absence of parallel effects on CD4+ T cells. Furthermore, in these individuals HAART with growth hormone resulted in an enhancement of cytokine-driven NK cell activation and IFN-gamma production compared to the HAART-only baseline.

Antibiotic resistance profiles are useful in directing therapeutic strategies during bacterial infections. Patterns of antimicrobial resistance in Streptococcus pneumoniae and Pseudomonas aeruginosa associated pneumonia were investigated in an HIV-1 infected cohort during the era of highly active antiretroviral therapy. The median CD4 count at presentation was significantly lower for cases of P aeruginosa than for S pneumoniae. However, the number of antibiotic resistant cases of P aeruginosa decreased throughout the study period, while the incidence of S pneumoniae remained unchanged. In contrast to pneumococcal pneumonia, we show that antiretrovirals have protected from pneumonia due to antibiotic resistant P aeruginosa. These findings have implications for the treatment of individuals presenting with serious infections in which antibiotic therapy needs to be instituted before identification and sensitivities are known.

Pneumocystis carinii pneumonia (PCP) remains a serious opportunistic infection in HIV infected individuals. Seasonal changes in climate are associated with changes within individual susceptibility to infection. The possibility of monthly variability in the incidence of PCP was therefore examined by means of a cohort study of a database of 8640 HIV infected individuals attending the Chelsea and Westminster Hospital. There were 792 cases of PCP diagnosed since 1985. A marked decline was observed in the incidence of PCP in mid-1992 coincident with the introduction of PCP prophylaxis. There was a further decline in 1996 after the introduction of highly active antiretroviral therapy. Despite no significant monthly variation in the mean attendance to clinic and CD4 count, both new and all cases of PCP were higher in January than in other months (15.9% and 14.5% of all cases, respectively). A correlation with low rainfall in January and new cases of PCP was observed. These data are consistent with an influence of climatic conditions on the presentation of PCP. The diagnosis of PCP is more common in winter months suggesting that this is a transmissible infection.

Interleukin-16 (IL-16) and the beta-chemokines (RANTES, monocyte chemotactic protein-1 (MCP-1), macrophage inhibitory protein (MIP)-1alpha and (MIP)-1beta) are soluble in vitro suppressors of macrophage tropic HIV-1 strains. The reduction of HIV-1 RNA plasma levels in late-stage patients receiving protease inhibitors has been associated with increased concentrations of MIP-1alpha, MIP-1beta, RANTES and IL-16 and a decrease in levels of MCP-1. We determined plasma levels of MCP-1, MIP-1alpha, MIP-1beta, RANTES and IL-16 during the first 16 weeks of highly active antiretroviral therapy (HAART) in chronic HIV-1-infected patients. Patients were administered one of two therapeutic regimens based on either a protease inhibitor (PI) or a non-nucleoside reverse transcriptase inhibitor (NNRTI). No differences were seen in the levels of RANTES and IL-16 over the first 16 weeks of HAART in either treatment group. MCP-1 decreased significantly in the PI-treated group over the first 16 weeks of HAART (P = 0.0003). A significant increase was observed in the levels of MIP-1alpha and MIP-1beta in the NNRTI cohort (P = 0.0010 and P = 0.0012, respectively). A significant decrease in levels of MIP-1alpha and MIP-1beta (P = 0.0015 and P = 0.0299, respectively) was observed over the 16 weeks in the PI cohort. A significant difference was seen when the levels of MIP-1alpha and MIP-1beta were compared between the NNRTI and the PI cohorts at week 16 (P = 0.04 and P = 0.05, respectively). Evaluation of CCR5 expression ex vivo revealed no difference between the two treatment groups. Patients were genotyped for CCR5 Delta32 and the incidence of heterozygosity was lower than in the HIV-1 seronegative controls (3% compared to 19%).

Human immunodeficiency virus (HIV)-specific cytotoxic T lymphocyte (CTL) responses are detectable shortly after the acute phase of HIV infection, but they cannot control viral replication and prevent development of chronic immune suppression. This article describes a defect in the coexpression of perforin in granzyme A-positive CD8(+) T cells in lymphoid tissue from patients with acute HIV infection and a reduction in the perforin-dependent nuclear translocation of granzyme A. Furthermore, intracellular levels of HIV DNA and RNA found in lymphoid tissue were higher (10-100 times) than those found in blood, and blood samples showed more-coordinated cellular perforin/granzyme A expression. This suggests that mechanisms inhibiting CTL-mediated cytotoxicity are operative in lymphoid tissue early in the course of HIV infection.

Individuals coinfected with human immunodeficiency virus 1 (HIV-1) and hepatitis B virus (HBV) often receive treatment with an antiretroviral regimen including lamivudine. Lamivudine monotherapy for HBV may lead to drug-resistant mutations in a significant number of patients. The virological and biochemical responses of 8 patients coinfected with HBV/HIV-1 treated with both lamivudine and famciclovir were studied. Patients exhibiting HBV viral rebound at 1 year were analyzed for the emergence of HBV polymerase mutations. Only 1 patient had no prior exposure to lamivudine. Addition of famciclovir to the treatment regimen resulted in a median fall in HBV DNA level of 0.33 log(10) at 3 months and an overall rise in HBV DNA level of 3 log(10) at 12 months. The only patient in whom durable viral suppression and HBV e antigen seroconversion were noted began receiving lamivudine and famciclovir simultaneously. HBV polymerase gene sequencing identified resistance-associated mutations in 6 of 7 patients with viral rebound. Sequential nucleoside analogue therapy is unlikely to be successful in achieving long-term suppression of HBV replication, and combination therapy should be considered at treatment initiation.

The steady-state pharmacokinetics of efavirenz and nevirapine, when used in combination to treat human immunodeficiency virus type 1 (HIV-1)-infected subjects, were investigated. HIV-1-infected persons who had used efavirenz (600 mg once daily) for > or =2 weeks were eligible for study inclusion. The plasma pharmacokinetics of efavirenz were determined over 24 h. Subsequently, nevirapine (400 mg once daily) was added to the regimen. After 4 weeks, the pharmacokinetics of efavirenz and nevirapine were assessed over 24 h. The differences between the pharmacokinetic parameters of efavirenz with and without nevirapine were analyzed, and the pharmacokinetics of nevirapine were compared with those in historical control patients. The exposure to efavirenz when combined with nevirapine was significantly decreased by 22% (area under the plasma concentration vs. time curve), 36% (minimum plasma concentration), and 17% (maximum plasma concentration). Nevirapine pharmacokinetics appear to be unaffected by coadministration of efavirenz, compared with data from historical control patients.

In this study, we compared human immunodeficiency virus (HIV) type 1-specific proliferative responses with HIV-1-induced intracellular cytokine production in a cohort of clinically nonprogressing patients and individuals with progressive HIV-1 infection. We found strong HIV-1-specific proliferative responses in the clinical nonprogressor cohort that correlated with significant numbers of circulating HIV-1-specific CD4(+) T cells. In contrast, HIV-1-specific proliferative responses were absent in most individuals with progressive HIV-1 infection, even though interferon-gamma-producing HIV-1-specific CD4(+) T cells were detectable by flow cytometry. The implication of these data is that the important dysfunction seen in most HIV-positive patients from very early in disease may be an inability of HIV-1-specific CD4(+) memory T cells to proliferate in response to HIV antigens rather than an absolute loss of circulating virus-specific CD4(+) T cells.

Highly active anti-retroviral therapy (HAART) is associated with reduction in the morbidity and mortality of patients with advanced HIV-1 disease. The ability of such treatment to improve immune responses against HIV-1 and opportunistic pathogens is variable and limited. Addition of cytokine immunotherapy to this treatment may improve immune responses. IL-2 with or without granulocyte-macrophage colony-stimulating factor (GM-CSF) was administered to HIV-1+ individuals receiving HAART with undetectable viral loads, and CD4 counts < 100 cells/microl. In one patient presenting with Mycobacterium avium complex (MAC) infection, we evaluated the effect of cytokine immunotherapy on lymphocyte phenotype; plasma viral load; proliferative responses to mitogens, recall and HIV-1 antigens; cytokine production and message in response to non-specific and specific stimuli; and natural killer (NK) cell activity. Proliferation assays were performed in two similar patients. Before cytokine immunotherapy the predominant CD8+ population was mainly CD28-. No proliferation or IL-2 production was seen in response to mitogens, recall or HIV-1 antigens; and no HIV-1 peptide-specific interferon-gamma (IFN-gamma)-secreting cells were present. Low levels of IL-4 were detected in response to antigens to which patients had been exposed, associated with up-regulated expression of costimulatory molecules influenced by IL-4. Following IL-2 administration, loss of IL-4 was associated with increased NK cell activity and HIV-1 peptide-specific and non-specific IFN-gamma-producing cells. Proliferative responses associated with IL-2 production and responsiveness were only seen after subsequent concomitant administration of GM-CSF with IL-2. These changes mirrored clinical improvement. An imbalance of lymphocyte subsets may account for immune unresponsiveness when receiving HAART. Restoration of responses following immunotherapy suggests a shift towards a lymphocyte profile with anti-pathogen activity.

HIV+ individuals with human CMV (HCMV) reactivation have a CD3 receptor-mediated T cell hyporesponsiveness when compared with CD4-matched HIV+ and HCMV- control groups. The impairment of proliferation was not reversed by exogenous IL-2. A typical increase in NFkappaB expression was observed following cross-linking of the CD3 receptor, but did not lead to increased CD25 cell surface expression or cell proliferation. The HCMV-induced non-responsiveness was not observed when cells were stimulated with phorbol esters. Lymphocytes cultured with media collected from cell cultures infected with HCMV showed a dose-dependent inhibition in the total T cell population even though cells staining dually for CD8/57 increased in number. The altered growth factor requirements of CD8/57+ cells may therefore account for their presence in AIDS and patients following bone marrow transplantation.

We report the first case of aquagenic urticaria in a patient with human immunodeficiency virus (HIV) infection. This is a rare physical urticaria not previously described in this context. The disorder proved unamenable to conventional treatment with antihistamines, but did respond dramatically to stanozolol, suggesting a novel indication for this anabolic steroid.

We studied 124 homosexual men aged 36.7 +/- 7.6 years (range 23-57) using Doppler echocardiography. One hundred and one patients (Group A) had had acquired immunodeficiency syndrome for 1.6 +/- 1.0 years and 23 patients (Group B) had had HIV infection without opportunistic infections for 3.2 +/- 2.3 years. Doppler echocardiography was normal in 31% of Group A patients and in 61% of Group B. Pericardial effusion was found in 44 Group A patients (44%) and two Group B patients (9%). In Group A, left ventricular dilatation and/or dysfunction were found in 20 patients (20%), aortic root dilatation and regurgitation in eight patients (8%) and an intracardiac echogenic mass in seven patients (7%); in Group B one patient (4%) had an intracardiac mass. Forty-four (44%) Group A patients had cardiac presentations, and of these 22 had cardiomegaly with clinical signs of heart failure; 10 patients had tachyarrhythmias compared to only two in Group B. Although the CD4 lymphocyte count (%) was significantly lower in Group A than in Group B (5.4 +/- 6.1 vs 13.3 +/- 7.3, P < 0.001), the presence of pericardial effusion, left ventricular dysfunction, right-sided cardiac enlargement or the duration of HIV infection, did not relate to the CD4 level in either group. Although often not diagnosed clinically, cardiac involvement in patients with AIDS is a clinical reality, with pericardial effusion, cardiomyopathy and left ventricular dysfunction appearing to have a high prevalence in male homosexual patients with AIDS. These clinical and echocardiographic findings are associated with clinically apparent intercurrent opportunistic infections, rather than the HIV virus per se, or the severity of infection as reflected by the CD4 count.