Cofactors in male-female sexual transmission of human immunodeficiency virus type 1

In a study of human immunodeficiency virus type 1 (HIV-1)-uninfected African prostitutes, 83 (67%) of 124 seroconverted to HIV-1. Oral contraceptive use (odds ratio [OR], 3.1; 95% confidence interval [CI], 1.1-8.6; P less than .03), genital ulcers (mean annual episodes, 1.32 +/- 0.55 in seroconverting women vs. 0.48 +/- 0.21 in seronegative women; P less than .02) and Chlamydia trachomatis infections (OR, 3.6; CI, 1.3-11.0; P less than .02) were associated with increased risk of HIV-1 infection. Condom use reduced the risk of HIV-1 infection (OR, 0.11; CI, 0.05-0.27; P less than .0001). Stepwise logistic regression analysis confirmed independent associations between HIV-1 infection and oral contraceptive use, condom use, genital ulcers, and C. trachomatis. The presence of other sexually transmitted diseases may in part explain the heterosexual HIV-1 epidemic in Africa and may represent important targets for intervention to control HIV-1 infection.

Female to male transmission of human immunodeficiency virus type 1: risk factors for seroconversion in men

To determine the frequency and risk factors for female to male sexual transmission of human immunodeficiency virus type 1 (HIV-1), a prospective study was carried out in 422 men who had acquired a sexually transmitted disease (STD) from a group of prostitutes with a prevalence of HIV-1 infection of 85%. The initial seroprevalence of HIV among the men was 12%. 24 of 293 (8.2%) initially seronegative men seroconverted to HIV-1. Newly acquired infection was independently associated with frequent prostitute contact (risk ratio 3.2, 95% confidence interval 1.2-8.1), with the acquisition of genital ulcer disease (risk ratio 4.7, 95% confidence interval 1.3-17.0), and with being uncircumcised (risk ratio 8.2, 95% confidence interval 3.0-23.0). 96% of documented seroconversions occurred in men with one or both of the latter two risk factors. In a subgroup of 73 seronegative men who reported a single prostitute sexual contact, the frequency of HIV-1 infection was 8.2% during 12 weeks of observation. No man without a genital ulcer seroconverted. A cumulative 43% of uncircumcised men who acquired an ulcer seroconverted to HIV-1 after a single sexual exposure. These data indicate an extremely high rate of female to male transmission of HIV-1 in the presence of STD and confirm a causal relation between lack of male circumcision, genital ulcer disease, and susceptibility to HIV-1 infection.

Randomised placebo-controlled trial of ritonavir in advanced HIV-1 disease. The Advanced HIV Disease Ritonavir Study Group

BACKGROUND

Ritonavir is a potent, orally bioavailable inhibitor of HIV-1 protease. We undertook an international, multicentre, randomised, double-blind, placebo-controlled trial of ritonavir in patients with HIV-1 infection and CD4-lymphocyte counts of 100 cells/microL or less, who had previously been treated with antiretroviral drugs.

METHODS

1090 patients were randomly assigned twice-daily liquid oral ritonavir 600 mg (n = 543) or placebo (n = 547) while continuing treatment with up to two licensed nucleoside agents. The primary study outcome was any first new, or specified recurrent, AIDS-defining event or death. Open-label ritonavir was provided after 16 weeks in the study to any patient who had an AIDS defining event.

FINDINGS

The baseline median CD4-lymphocyte count was 18 (IQR 10-43)/microL in the ritonavir group and 22 (10-47)/microL in the placebo group. Study medication was discontinued in 114 (21.1%) ritonavir-group patients and 45 (8.3%) placebo-group patients mainly because of initial adverse symptoms. Outcomes of AIDS-defining illness or death occurred in 119 (21.9%) ritonavir-group patients and 205 (37.5%) placebo-group patients (hazard ratio 0.53 [95% CI 0.42-0.66]; log-rank p < 0.0001) during median follow-up of 28.9 weeks, with loss to follow-up of 15 (1.4%) patients. Ritonavir was then offered to all patients; at median follow-up of 51 weeks, 87 (16%) ritonavir-group patients had died of any cause versus 126 (23%) placebo-group patients (hazard ratio 0.69 [95% CI 0.52-0.91], log-rank p = 0.0072).

INTERPRETATION

Although earlier intervention with combination therapy may provide much more effective treatment, ritonavir in patients with advanced disease and extensive previous antiretroviral use is safe and effective, lowers the risk of AIDS complications, and prolongs survival.

A systematic review of the epidemiologic interactions between classic sexually transmitted diseases and HIV: how much really is known?

BACKGROUND

Many studies have explored the role of "classic" sexually transmitted diseases (STDs) in determining the pattern of HIV epidemics. However, the many different STDs may contribute in different ways, at different magnitudes.

GOAL

To review available studies on the bidirectional interactions of HIV and STDs to explore the extent of current knowledge on the different influences of the varied STDs in heterosexual HIV epidemics.

METHODS

Longitudinal studies on susceptibility and controlled studies on infectiousness and duration of disease identified on electronic databases through reference lists and citation indices up to the end of 1999 were systematically reviewed, including meta-analyses assessing the influence of STDs on susceptibility to HIV.

RESULTS

Studies have a clear publication bias with a significant result that hinders robust interpretation. However, genital ulcerative disease appears to have a greater impact than nonulcerative disease, and men are more affected than women by the effects of STDs on susceptibility to HIV. There is evidence that STDs increase the infectiousness of HIV from men to women, whereas the evidence is more equivocal for the infectiousness of women. Few studies identify the impact of different STDs, and there is a marked lack of studies investigating the impact of HIV infection on the transmission of other STDs.

CONCLUSIONS

A large body of work has measured the association between STDs and HIV. However, publication bias and gaps in the focus of studies mean that a detailed, quantitative understanding of the interaction requires much more attention.

Two controlled trials of rifabutin prophylaxis against Mycobacterium avium complex infection in AIDS

BACKGROUND

Disseminated Mycobacterium avium complex infection eventually develops in most patients with the acquired immunodeficiency syndrome (AIDS). This infection results in substantial morbidity and reduces survival by about six months.

METHODS

We conducted two randomized, double-blind, multicenter trials of daily prophylactic treatment with either rifabutin (300 mg) or placebo. All the patients had AIDS and CD4 cell counts < or = 200 per cubic millimeter. The primary end point was M. avium complex bacteremia as assessed monthly by blood culture. The secondary end points were signs and symptoms associated with disseminated M. avium complex infection, adverse events, hospitalization, and survival.

RESULTS

In the first trial, M. avium complex bacteremia developed in 51 of 298 patients (17 percent) assigned to placebo and 24 of 292 patients (8 percent) assigned to rifabutin (P < 0.001). In the second trial, bacteremia developed in 51 of 282 patients in the placebo group (18 percent) and 24 of 274 patients in the rifabutin group (9 percent) (P = 0.002). Rifabutin significantly delayed fatigue, fever, decline in the Karnofsky performance score (by > or = 20 percent), decline in the hemoglobin level (by more than 10 percent), elevation in alkaline phosphatase, and hospitalization. The incidence of adverse events was similar with rifabutin and placebo. Overall survival did not differ significantly between the two groups, although there were fewer deaths with rifabutin (33) than with placebo (47) during the double-blind phase (P = 0.086). The distribution of minimal inhibitory concentrations of rifabutin among the isolates of M. avium complex did not differ significantly between the treatment groups.

CONCLUSIONS

Rifabutin, given prophylactically, reduces the frequency of disseminated M. avium complex infection in patients with AIDS and CD4 counts < or = 200 per cubic millimeter.

Human immunodeficiency virus infection among men with sexually transmitted diseases. Experience from a center in Africa

Heterosexual transmission of the human immunodeficiency virus (HIV) appears to occur readily in Africa but less commonly in North America and Europe. We conducted a case-control study among men attending a clinic for sexually transmitted diseases in Nairobi to determine the prevalence of HIV infection and the risk factors involved. HIV antibody was detected in 11.2 percent of 340 men who enrolled in the study. Reports of nonvaginal heterosexual intercourse and homosexuality were notably rare. Recent injections and blood transfusions were not associated with HIV infection. Travel and frequent contact with prostitutes were associated with HIV seropositivity. Men who were uncircumcised were more likely to have HIV infection (odds ratio, 2.7; P = 0.003), as were those who reported a history of genital ulcers (odds ratio, 7.2; P less than 0.001). A current diagnosis of genital ulcers was also associated with HIV seropositivity (odds ratio, 2.0; P = 0.028). Multivariate analysis revealed an independent association of genital ulcers with HIV infection in both circumcised and uncircumcised men. Uncircumcised men were more frequently infected with HIV, regardless of a history of genital ulcers. Our study finds that genital ulcers and an intact foreskin are associated with HIV infection in men with a sexually transmitted disease. Genital ulcers may increase men's susceptibility to HIV, or they may increase the infectivity of women infected with HIV. The intact foreskin may operate to increase the susceptibility to HIV.

CPG 7909, an immunostimulatory TLR9 agonist oligodeoxynucleotide, as adjuvant to Engerix-B HBV vaccine in healthy adults: a double-blind phase I/II study

Oligodeoxynucleotides containing immunostimulatory CpG motifs (CpG ODN) act as potent Th1-like immune enhancers with many antigens in animal models. We have extended these observations to the first clinical evaluation of the safety, tolerability and immunogenicity of CPG 7909 when added to a commercial HBV vaccine. In a randomized, double-blind phase I dose escalation study, healthy volunteers aged 18-35 years were vaccinated at 0, 4 and 24 weeks by intramuscular injection with Engerix-B (GlaxoSmithKline). The regular adult dose of 20 microg recombinant hepatitis B surface antigen (HBsAg) adsorbed to alum was administered mixed with saline (control) or with CPG 7909 at one of three doses (0.125, 0.5 or 1.0 mg). HBsAg-specific antibody responses (anti-HBs) appeared significantly sooner and were significantly higher at all timepoints up to and including 24 weeks in CPG 7909 recipients compared to control subjects (p< or = 0.001). Strikingly, most CpG 7909-vaccinated subjects developed protective levels of anti-HBs IgG within just two weeks of the priming vaccine dose. A trend towards higher rates of positive cytotoxic T cell lymphocyte responses was noted in the two higher dose groups of CPG 7909 compared to controls. The most frequently reported adverse events were injection site reactions, flu-like symptoms and headache. While these were more frequent in CPG 7909 groups than in the control group (p<0.0001), most were reported to be of mild to moderate intensity regardless of group. In summary, CPG 7909 as an adjuvant to Engerix-B was well-tolerated and enhanced vaccine immunogenicity. CPG 7909 may allow the development of a two-dose prophylactic HBV vaccine.

Safety and immunogenicity of CPG 7909 injection as an adjuvant to Fluarix influenza vaccine

CPG 7909, a 24-mer B-Class CpG oligodeoxynucleotide (ODN), was tested for safety, tolerability and its ability to augment the immunogenicity of a commercial trivalent killed split influenza vaccine (Fluarix containing A/Beijing/262/95, A/Sydney/5/97 and B/Harbin/7/94; SmithKline Beecham) in a phase Ib blinded, randomized, controlled clinical trial. Sixty healthy volunteers were recruited in two consecutive cohorts of 30 subjects, who were randomly assigned to receive Fluarix plus 1mg CPG 7909 or Fluarix plus saline control (15 subjects each). Vaccines were administered by intramuscular injection on a single occasion with subjects in the first cohort receiving a 1/10th dose of Fluarix and those in the second cohort receiving the full-dose. All safety measures including physical evaluation, laboratory blood assays, and assays for DNA autoimmunity were within normal values except for transient and clinically inconsequential decreases in total white blood cell counts in groups receiving CPG 7909. All vaccines were found to be generally well tolerated with similar frequency and intensity for most adverse reactions for groups receiving CPG 7909 as controls. Exceptions were injection site pain and headache, which were reduced in frequency in subjects receiving the 1/10th Fluarix dose without CpG, compared to the frequency in all other groups. There was a lack of pre-existing immunity, defined as hemagglutinin inhibition (HI) activity < or =20, for all subjects to the influenza strains A/Beijing/262/95 and B/Harbin/7/94 and for some subjects to A/Sydney/5/97. Post-vaccination humoral immune responses, as determined 2 and 4 weeks later by assay of HI activity and ELISA to detect antibodies against hemagglutinin (anti-HA) were similar for both full and reduced Fluarix doses but the cellular immune responses (measured as PBMC antigen-specific IFN-gamma secretion) were reduced in the 1/10th Fluarix dose group. Humoral responses were not significantly enhanced by the addition of CPG 7909, except in individuals with pre-existing immunity to A/Sydney/5/97 strain (baseline HI activity titre >20), where there was a trend to higher HI activity with CPG 7909 (P = 0.06). The addition of CPG 7909 to the 1/10th dose of Fluarix did however result in significantly higher levels of IFN-gamma secretion from peripheral blood mononuclear cells recovered at 4 weeks and restimulated ex vivo with A/Beijing/262/95 (P = 0.048) and B/Harbin/7/94 (P = 0.0057), restoring these to the level seen with full-dose vaccine. These results suggest that addition of CPG 7909 to Fluarix may allow the use of reduced vaccine doses without reduced immunogenicity.

Steady-State pharmacokinetics and tolerability of trans-resveratrol 2000 mg twice daily with food, quercetin and alcohol (ethanol) in healthy human subjects

BACKGROUND AND OBJECTIVE

Trans-resveratrol is a polyphenol, which is found in red wine and has cancer chemo-preventive properties and disease-preventive properties. The pharmacokinetics of trans-resveratrol have been investigated in single-dose studies and in studies with relatively low dosages. The present study aimed to investigate the steady-state pharmacokinetics and tolerability of trans-resveratrol 2000 mg twice daily with food, quercetin and alcohol (ethanol).

METHODS

This was a two-period, open-label, single-arm, within-subject control study in eight healthy subjects. The steady-state 12-hour pharmacokinetics of trans-resveratrol 2000 mg twice daily were studied with a standard breakfast, a high-fat breakfast, quercetin 500 mg twice daily and 5% alcohol 100 mL. Trans-resveratrol plasma concentrations were determined using liquid chromatography with tandem mass spectrometry.

RESULTS

The mean (SD) area under the plasma concentration-time curve from 0 to 12 hours (AUC(12)) and maximum plasma concentration (C(max)) of trans-resveratrol were 3558 (2195) ng * h/mL and 1274 (790) ng/mL, respectively, after the standard breakfast. The high-fat breakfast significantly decreased the AUC(12) and C(max) by 45% and 46%, respectively, when compared with the standard breakfast. Quercetin 500 mg twice daily or 5% alcohol 100 mL did not influence trans-resveratrol pharmacokinetics. Diarrhoea was reported in six of the eight subjects. Significant but not clinically relevant changes from baseline were observed in serum potassium and total bilirubin levels.

CONCLUSION

Trans-resveratrol 2000 mg twice daily resulted in adequate exposure and was well tolerated by healthy subjects, although diarrhoea was frequently observed. In order to maximize trans-resveratrol exposure, it should be taken with a standard breakfast and not with a high-fat meal. Furthermore, combined intake with quercetin or alcohol did not influence trans-resveratrol exposure.

Cardiac complications in patients with community-acquired pneumonia: a systematic review and meta-analysis of observational studies

BACKGROUND

Community-acquired pneumonia (CAP) is a leading cause of morbidity and mortality. CAP can trigger acute cardiac events. We sought to determine the incidence of major cardiac complications in CAP patients to characterize the magnitude of this problem.

METHODS AND FINDINGS

Two investigators searched MEDLINE, Scopus, and EMBASE for observational studies of immunocompetent adults with clinical and radiological evidence of CAP that reported any of the following: overall cardiac complications, incident heart failure, acute coronary syndromes (ACS), or incident cardiac arrhythmias occurring within 30 days of CAP diagnosis. At a minimum, studies had to establish enrolment procedures and inclusion and exclusion criteria, enroll their patients sequentially, and report the incidence of cardiac complications as a function of their entire cohorts. Studies with focus on nosocomial or health care-associated pneumonia were not included. Review of 2,176 citations yielded 25 articles that met eligibility and minimum quality criteria. Seventeen articles (68%) reported cohorts of CAP inpatients. In this group, the pooled incidence rates for overall cardiac complications (six cohorts, 2,119 patients), incident heart failure (eight cohorts, 4,215 patients), acute coronary syndromes (six cohorts, 2,657 patients), and incident cardiac arrhythmias (six cohorts, 2,596 patients), were 17.7% (confidence interval [CI] 13.9-22.2), 14.1% (9.3-20.6), 5.3% (3.2-8.6), and 4.7% (2.4-8.9), respectively. One article reported cardiac complications in CAP outpatients, four in low-risk (not severely ill) inpatients, and three in high-risk inpatients. The incidences for all outcomes except overall cardiac complications were lower in the two former groups and higher in the latter. One additional study reported on CAP outpatients and low-risk inpatients without discriminating between these groups. Twelve studies (48%) asserted the evaluation of cardiac complications in their methods but only six (24%) provided a definition for them. Only three studies, all examining ACS, carried out risk factor analysis for these events. No study analyzed the association between cardiac complications and other medical complications or their impact on other CAP outcomes.

CONCLUSIONS

Major cardiac complications occur in a substantial proportion of patients with CAP. Physicians and patients need to appreciate the significance of this association for timely recognition and management of these events. Strategies aimed at preventing pneumonia (i.e., influenza and pneumococcal vaccination) in high-risk populations need to be optimized. Further research is needed to understand the mechanisms underlying this association, measure the impact of cardiac complications on other CAP outcomes, identify those patients with CAP at high risk of developing cardiac complications, and design strategies to prevent their occurrence in this population.

CPG 7909 adjuvant improves hepatitis B virus vaccine seroprotection in antiretroviral-treated HIV-infected adults

BACKGROUND

HIV patients are vaccine hyporesponsive.

METHODS

We evaluated CPG 7909, a synthetic oligodeoxynucleotide containing immunostimulatory CpG motifs, as an adjuvant to Engerix-B. A randomized, double-blind controlled trial was conducted to determine safety and hepatitis B virus (HBV) immunogenicity in adult HIV subjects on effective antiretroviral therapy. HBV-susceptible subjects, half of whom had failed previous vaccination, were vaccinated at 0, 1 and 2 months with a double dose of Engerix-B with/without (+/-) 1 mg CPG 7909. HBV immune subjects (anti-HBsAg titres > or = 10 mIU/l) received either CPG 7909 alone or saline. Safety, anti-HBs titres and lymphocyte proliferation response (LPR) to HBsAg were assessed over 12 months.

RESULTS

Vaccinations with Engerix B +/- CPG 7909 were well tolerated locally and systemically. HIV suppression and CD4 cell counts were maintained. Anti-HBs titers were significantly higher in vaccinees receiving CPG 7909, for all time points after the second dose. Seroprotective titres (> or = 10 mIU/ml) by 6 and 8 weeks, and 12 months were found in 89, 89, and 100% of subjects receiving CPG 7909 compared to 53, 42, and 63% of controls respectively (P = 0.029, 0.005, and 0.008). HBsAg LPR was increased at all time-points up to 12 months after vaccination with addition of CPG 7909 (P < 0.05).

CONCLUSIONS

Addition of CPG 7909 achieves rapid, higher, and sustained HBV seroprotection and increases HBV-specific T helper cell response to HBV vaccine in HIV subjects. These results confirm a potential adjuvant role for CPG 7909 in vaccine hyporesponsive populations including those living with HIV.

Ritonavir and saquinavir combination therapy for the treatment of HIV infection

OBJECTIVE

To evaluate the safety and antiretroviral activity of ritonavir (Norvir) and saquinavir (Invirase) combination therapy in patients with HIV infection.

DESIGN

A multicenter, randomized, open-label clinical trial.

SETTING

Seven HIV research units in the USA and Canada.

PATIENTS

A group of 141 adults with HIV infection, CD4 T lymphocyte counts of 100-500 x 10(6) cells/l, whether treated previously or not with reverse transcriptase inhibitor therapy, but without previous HIV protease inhibitor drug therapy.

INTERVENTIONS

After discontinuation of prior therapy for 2 weeks, group I patients were randomized to receive either combination (A) ritonavir 400 mg and saquinavir 400 mg twice daily or (B) ritonavir 600 mg and saquinavir 400 mg twice daily. After an initial safety assessment of group I patients, group II patients were randomized to receive either (C) ritonavir 400 mg and saquinavir 400 mg three times daily or (D) ritonavir 600 mg and saquinavir 600 mg twice daily. Investigators were allowed to add up to two reverse transcriptase inhibitors (including at least one with which the patient had not been previously treated) to a patient's regimen after week 12 for failure to achieve or maintain an HIV RNA level < or = 200 copies/ml documented on two consecutive occasions.

MEASUREMENTS

Plasma HIV RNA levels and CD4+ T-lymphocyte counts were measured at baseline, every 2 weeks for 2 months, and monthly thereafter. Safety was assessed through the reporting of adverse events, physical examinations, and the monitoring of routine laboratory tests.

RESULTS

The 48 weeks of study treatment was completed by 75% (106/141) of the patients. Over 80% of the patients on treatment at week 48 had an HIV RNA level < or = 200 copies/ml. In addition, intent-to-treat and on-treatment analyses revealed comparable results. Suppression of plasma HIV RNA levels was similar for all treatment arms (mean areas under the curve minus baseline through 48 weeks were-1.9, -2.0, -1.6, -1.8 log10 copies/ml in ritonavir-saquinavir 400-400 mg twice daily, 600-400 mg twice daily, 400-400 mg three times daily, and 600-600 mg twice daily, respectively). Median CD4 T-lymphocyte count rose by 128 x 10(6) cells/l from baseline, with an interquartile range (IQR) of 82-221 x 10(6) cells/l. The most common adverse events were diarrhea, circumoral paresthesia, asthenia, and nausea. Reversible elevation of serum transaminases (> 5 x upper limit of normal) occurred in 10% (14/141) of the patients enrolled in this study and was associated with baseline abnormalities in liver function tests, baseline hepatitis B surface antigen positivity, or hepatitis C antibody positivity (relative risk, 5.0; 95% confidence interval 1.5-16.9). Most moderate or severe elevations in liver function tests occurred in patients treated with ritonavir-saquinavir 600-600 mg twice daily.

CONCLUSIONS

Ritonavir 400 mg combined with saquinavir 400 mg twice daily with the selective addition of reverse transcriptase inhibitors was the best-tolerated regimen of four dose-ranging regimens and was equally as active as the higher dose combinations in HIV-positive patients without previous protease inhibitor treatment.

Prevention of transmission of human immunodeficiency virus in Africa: effectiveness of condom promotion and health education among prostitutes

Condom use was assessed after a programme of education about the acquired immunodeficiency syndrome and a condom distribution programme in a well-characterised prostitute population in Nairobi. Women received their education at group meetings (barazas) and at individual counselling sessions during which they were given the results of serological tests for the human immunodeficiency virus (group 1) or at barazas only (group 2), or through very little of either (group 3). During the counselling sessions free condoms were distributed. Before either of the programmes started, 10%, 9%, and 7% of groups 1, 2, and 3 women, respectively, reported occasional use of condoms. By November 1986, 80%, 70%, and 58% of groups 1, 2, and 3 women, respectively, reported at least some condom use. The mean frequency of condom use was 38.7 (SD 31.8)%, 34.6 (34.5)%, and 25.6 (29.5)% of sexual encounters in groups 1, 2, and 3 women. 20 of 28 women who were non-condom-users seroconverted compared with 23 of 50 women who reported some use of condoms.

Meta-analysis: intravenous immunoglobulin in critically ill adult patients with sepsis

BACKGROUND

Intravenous immunoglobulin therapy has been proposed as an adjuvant treatment for sepsis. Yet, its benefit remains unclear, and its use is not currently recommended.

PURPOSE

To evaluate the effect of polyclonal intravenous immunoglobulin therapy on death in critically ill adult patients with sepsis.

DATA SOURCES

MEDLINE (1966 to May 2006) and the Cochrane Central Register of Controlled Trials (May 2006 edition).

STUDY SELECTION

All randomized, controlled trials of critically ill adult patients with sepsis, severe sepsis, or septic shock who received polyclonal intravenous immunoglobulin therapy or placebo or no intervention were selected. No restrictions were made for study language or type of publication.

DATA EXTRACTION

Data were independently extracted by 2 investigators using a standardized form.

DATA SYNTHESIS

The literature search identified 4096 articles, of which 33 were deemed to be potentially eligible. Twenty trials (n = 2621) met eligibility criteria and were included in the analysis. Polyclonal intravenous immunoglobulin therapy was associated with an overall survival benefit (risk ratio, 0.74 [95% CI, 0.62 to 0.89]) compared with placebo or no intervention. In sensitivity analyses, documented survival improved when the analysis was limited to published, peer-reviewed trials (risk ratio, 0.72 [CI, 0.58 to 0.89]) (17 trials [n = 1865]) and blinded trials (risk ratio, 0.61 [CI, 0.40 to 0.93) (7 trials [n = 896]). Severe sepsis or septic shock (risk ratio, 0.64 [CI, 0.52 to 0.79]) (11 trials [n = 689]), receiving a total dose regimen of 1 gram or more per kilogram of body weight (risk ratio, 0.61 [CI, 0.40 to 0.94]) (7 trials [n = 560]), and receiving therapy for longer than 2 days (risk ratio, 0.66 [CI, 0.53 to 0.82]) (17 trials [n = 1847]) were strongly associated with this survival benefit.

LIMITATIONS

Most trials were published before new developments modifying the care and outcome of critically ill patients with sepsis including early goal-directed therapy and activated protein C treatment, were introduced.

CONCLUSIONS

A survival benefit was observed for patients with sepsis who received polyclonal intravenous immunoglobulin therapy compared with those who received placebo or no intervention. A large, randomized, controlled trial of polyclonal intravenous immunoglobulin therapy should be performed on the basis of the methodological limitations of the current literature, the potential benefit from this therapy in more severely ill patients, and the potential effect of dosage and duration of this therapy.

A review of low-dose ritonavir in protease inhibitor combination therapy

The pharmacokinetics of protease inhibitors center around the microsomal enzyme cytochrome P-450 3A4. As a potent inhibitor of this enzyme, ritonavir can increase the bioavailability and half-life of coadministered protease inhibitors. Evidence suggests that increased exposure to protease inhibitors is clinically relevant. Antiretroviral treatment with low-dose ritonavir-boosted lopinavir, indinavir, and saquinavir has durable virological activity and shows impressive immune reconstitution. Although tolerable in most cases, gastrointestinal side effects, hepatotoxicity, and blood lipid abnormalities remain relevant issues. Additional study will elucidate the advantages and disadvantages of twice-daily, low-dose ritonavir-boosted regimens and determine whether once-daily regimens based on this principle will have a lasting role in clinical practice.

Reduced plasma concentrations of antituberculosis drugs in patients with HIV infection

BACKGROUND

Reports suggest that antituberculosis drugs are malabsorbed in patients with advanced HIV disease.

OBJECTIVE

To evaluate the pharmacokinetics of antituberculosis agents in HIV-seropositive patients at different stages of disease.

DESIGN

Parallel study.

SETTING

Two hospital outpatient clinics.

PARTICIPANTS

12 healthy volunteers, 12 patients with asymptomatic HIV disease, 12 patients with symptomatic HIV disease, and 12 patients with symptomatic HIV disease and diarrhea.

MEASUREMENTS

Drug plasma concentrations were measured over 24 hours on day 4 of concurrent therapy.

INTERVENTION

Oral isoniazid (300 mg/d), rifampin (600 mg/d), pyrazinamide (1000 mg/d), and ethambutol (1000 mg/d).

RESULTS

Reduced total drug exposure to rifampin and pyrazinamide was associated with D-xylose malabsorption in persons with HIV infection or AIDS. Peak drug exposure to isoniazid was lower in patients with diarrhea.

CONCLUSIONS

Reduced total drug exposure may be related to malabsorption in persons with HIV infection or AIDS.

A 96-week comparison of lopinavir-ritonavir combination therapy followed by lopinavir-ritonavir monotherapy versus efavirenz combination therapy

Antiretroviral-naive HIV-1-infected volunteers received zidovudine/lamivudine plus either lopinavir/ritonavir (n=104) or efavirenz (n=51). Lopinavir/ritonavir-treated subjects demonstrating 3 consecutive monthly HIV-1 RNA levels <50 copies/mL started lopinavir/ritonavir monotherapy. In previous-failure=failure analysis, 48% (lopinavir/ritonavir) and 61% (efavirenz) maintained HIV-1 RNA at <50 copies/mL through week 96, (P= .17; 95% confidence interval [CI] for the difference, -29% to 4%); in noncompletion=failure analysis, 60% (lopinavir/ritonavir) and 63% (efavirenz) maintained HIV-1 RNA at <50 copies/mL at week 96 (P= .73; 95% CI for the difference, -19% to 13%). Significant sparing of peripheral lipoatrophy was noted in the lopinavir/ritonavir simplification strategy. This study has provided important information for future studies using treatment simplified to lopinavir/ritonavir monotherapy.

Co-administration of CpG oligonucleotides enhances the late affinity maturation process of human anti-hepatitis B vaccine response

We assessed the avidity maturation process elicited by human immunization with alum-adsorbed HBsAg alone or with a novel adjuvant containing CpG motifs (CpG 7909). Mean avidity indexes and distribution of low- and high-avidity anti-HBs indicated that avidity maturation essentially takes place late after priming. CpG 7909 markedly enhanced this affinity maturation process, increasing the pool of high-avidity antibodies. The influence of CpG 7909 was antigen-specific, isotype-specific and distinct from the influence on anti-HBs production, as avidity did not correlate with anti-HBs IgG titers. This is the first demonstration that a novel human adjuvant may induce antibodies with higher antigen-binding affinity.

Improvement in cell-mediated immune function during potent anti-human immunodeficiency virus therapy with ritonavir plus saquinavir

Inhibiting human immunodeficiency virus (HIV) replication with potent antiretroviral therapy may result in improved immune function, and this may lead to favorable outcomes, independent of changes in CD4+ lymphocyte count. The effect of combination protease inhibitor therapy (ritonavir plus saquinavir) on functional measures of cell-mediated immunity in 41 HIV-infected patients from one center of a multicenter trial was investigated. After 24 weeks, median plasma virus load decreased from 4.74 log10 copies/mL to below the detection limit of the assay (2.30 log10), and mean CD4+ lymphocyte count increased from 284 cells/microL to 413 cells/microL. Proliferative responses to phytohemagglutinin developed in 21 of 34 patients in whom responses were absent at baseline. Increases were observed in interleukin-2, -12, and -10 production and in the expression of CD28 on CD8+ lymphocytes. Initiation of potent anti-HIV therapy results in a degree of immune restoration, suggesting that HIV-induced immune suppression is a dynamic and potentially reversible process.

Breast cancer incidence highest in the range of one species of house mouse, Mus domesticus

Incidence of human breast cancer (HBC) varies geographically, but to date no environmental factor has explained this variation. Previously, we reported a 44% reduction in the incidence of breast cancer in women fully immunosuppressed following organ transplantation (Stewart et al (1995) Lancet 346: 796-798). In mice infected with the mouse mammary tumour virus (MMTV), immunosuppression also reduces the incidence of mammary tumours. DNA with 95% identity to MMTV is detected in 40% of human breast tumours (Wang et al (1995) Cancer Res 55: 5173-5179). These findings led us to ask whether the incidence of HBC could be correlated with the natural ranges of different species of wild mice. We found that the highest incidence of HBC worldwide occurs in lands where Mus domesticus is the resident native or introduced species of house mouse. Given the similar responses of humans and mice to immunosuppression, the near identity between human and mouse MTV DNA sequences, and the close association between HBC incidence and mouse ranges, we propose that humans acquire MMTV from mice. This zoonotic theory for a mouse-viral cause of HBC allows testable predictions and has potential importance in prevention.

CPG 7909 adjuvant plus hepatitis B virus vaccination in HIV-infected adults achieves long-term seroprotection for up to 5 years

BACKGROUND

Human immunodeficiency virus (HIV)-infected persons are hyporesponsive to hepatitis B virus (HBV) vaccination. CPG 7909 is an oligodeoxynucleotide containing immunostimulatory CpG motifs that activate human B and plasmacytoid dendritic cells via Toll-like receptor 9. We previously reported that addition of CPG 7909 to a commercial HBV vaccine enhanced the kinetics, magnitude, and longevity of the seroprotective response over 48 weeks. We now report data for the 5-year period following vaccination.

METHODS

A randomized, double-blind, controlled trial was conducted to determine clinical safety and immunogenicity of HBV vaccine in adult HIV-infected subjects receiving effective antiretroviral therapy. HBV-susceptible subjects, one-half of whom had experienced previous vaccination failure, were vaccinated at 0, 1, and 2 months with a double adult dose of recombinant HBV vaccine, with or without 1 mg of CPG 7909 (19 subjects per arm). Titers of antibody to HBV surface antigen (anti-HBs) were measured at 6-month intervals for up to 60 months.

RESULTS

The proportion of participants achieving and retaining seroprotection (surface antibody titers, > or =10 mIU/mL) was greater in CPG 7909 recipients (P < .05 at all time points). Geometric mean anti-HBs titers were higher in the CPG 7909 group than in the control group (without CPG 7909 adjuvant) at all measured time points.

CONCLUSIONS

The immunostimulatory properties of CPG 7909 present an important strategy in achieving long-term protection in HIV-infected patients and other HBV vaccine-hyporesponsive populations.

Effect of ketoconazole on ritonavir and saquinavir concentrations in plasma and cerebrospinal fluid from patients infected with human immunodeficiency virus

AIM

Our aim was to evaluate the effect of ketoconazole on ritonavir and saquinavir plasma and cerebrospinal fluid (CSF) concentrations.

METHODS

Twelve patients who were human immunodeficiency virus-seropositive and who were receiving 400 mg of ritonavir and 400 mg of saquinavir twice daily completed a nonfasted, two-period, two-group, longitudinal pharmacokinetic study. Blood samples were collected over the daytime 12-hour dosing interval of the protease inhibitors at baseline (period 1, day 0) and after 10 days of coadministration of 200 mg (n = 6) or 400 mg (n = 6) of ketoconazole once daily (period 2, day 10). One set of paired CSF and blood samples was collected between 4 and 5 hours after the dose on both days.

RESULTS

Ketoconazole significantly increased area under the plasma concentration-time curve, plasma concentration at 12 hours after the dose, and half-life of ritonavir by 29% (95% confidence interval (CI), 13%-46%), 62% (95% CI, 37%-92%), and 31% (95% CI, 13%-51%), respectively. Similar increases of 37% (95% CI, 4%-81%), 94% (95% CI, 41%-167%), and 38% (95% CI, 15%-66%), respectively, were observed for these parameters for saquinavir. Ketoconazole significantly elevated ritonavir CSF concentration by 178% (95% CI, 59%-385%), from 2.4 to 6.6 ng/mL, with no change in paired unbound plasma level (26 ng/mL); this led to a commensurate 181% increase (95% CI, 47%-437%) in CSF/plasma unbound ratio. All pharmacokinetic changes were unrelated to ketoconazole dose or plasma exposures. Corresponding changes for saquinavir CSF pharmacokinetics were insignificant (P > .06); saquinavir CSF levels were unmeasurable in 7 patients (<0.2 ng/mL).

CONCLUSIONS

The disproportionate increase in CSF compared with plasma concentrations of ritonavir is consistent with ketoconazole inhibiting both drug efflux from CSF and systemic clearance.

Effect of fluconazole on zidovudine pharmacokinetics in patients infected with human immunodeficiency virus

The effect of a therapeutic dose of fluconazole on the disposition of zidovudine was evaluated in 12 men infected with human immunodeficiency virus. The study was designed as a randomized, two-period, two-treatment, crossover trial. On two occasions, 21 days apart, patients received either zidovudine alone or zidovudine (each, 200 mg every 8 h) and fluconazole (400 mg daily) for 7 days. Fluconazole coadministration decreased (P < .001) the apparent oral serum clearance of zidovudine by 43% and the apparent oral formation clearance to zidovudine glucuronide (GZDV) by 48%, resulting in increases (P < .002) in the area under the serum concentration time curve (74%), the maximum serum concentration (84%), and the terminal half-life (128%) of zidovudine. The molar ratio of GZDV to zidovudine recovered in urine was reduced by 34% with fluconazole (P < .001). These pharmacokinetic changes suggest that 400 mg of fluconazole inhibited the conversion of zidovudine to GZDV. Patients receiving this combination should be monitored for the development of zidovudine-related adverse reactions.

Decreased HIV-associated T cell apoptosis by HIV protease inhibitors

Antiretroviral treatment of patients infected with HIV results in improvements in CD4+ T cell number. Emerging evidence suggests that some of the improvements in CD4+ T cell number that occur in response to protease inhibitor (PI) therapy may not be accounted for solely by enhanced viral suppression, implying that PI may directly affect T cell survival. Since HIV T cell depletion is associated with enhanced apoptosis, we analyzed the effect of PIs on T cell apoptosis. In vitro treatment of peripheral blood lymphocytes (PBLs) from HIV-infected but untreated patients with reverse transcriptase inhibitors (RTIs) does not alter apoptosis, whereas PI treatment rapidly reduces CD4+ and CD8+ T cell apoptosis. In contrast, PI treatment does not alter apoptosis in PBL blasts from HIV-negative patients, or in Jurkat T cells. Consistent with this observation, 8 days of PI therapy in HIV-infected patients does not significantly alter plasma viremia, yet results in significant inhibition of CD4+ and CD8+ T cell apoptosis. The inhibitory effects of PI on apoptosis have implications concerning the treatment of HIV and its pathogenesis.

Normalization of natural killer cell function and phenotype with effective anti-HIV therapy and the role of IL-10

OBJECTIVES

Natural killer (NK) cell function is likely to be important in controlling HIV infection and opportunistic pathogens. We therefore evaluated NK function and phenotype over the course of antiretroviral therapy (ART) and examined the potential mechanisms of altered NK activity in HIV infection.

METHODS

We measured NK cell percentage, NK cytolytic activity (both by flow cytometry) and plasma IL-10 concentrations (by enzyme-linked immunosorbent assay) in 10 HIV-seropositive patients before and over one year of effective ART. To examine potential mechanisms of altered NK activity, we measured NK receptor expression in ART treated and untreated HIV-positive individuals by flow cytometry. As IL-10 enhances NK activity, we studied the effect of IL-10 on NK receptor expression and activity in peripheral blood mononuclear cells (PBMC) from HIV-seronegative individuals.

RESULTS

NK cytolytic activity was elevated in HIV infection and decreased with ART to levels observed in HIV-negative individuals. A greater proportion of NK cells from untreated HIV-positive individuals expressed the NK receptors CD158a and CD161 than either HIV-negative volunteers or effectively treated HIV-positive patients. NK cells from PBMC incubated with IL-10 demonstrated increases in CD158a, CD161 and CD94 expression and increases in cytolytic activity. The treatment-associated decrease in NK activity paralleled a decrease in IL-10 production.

CONCLUSION

The observation that IL-10 alters NK receptor expression similar to that observed in HIV infection, and the fact that NK receptor expression and activity normalize in parallel with ART-induced reduction of circulating IL-10 levels supports a role for IL-10 in NK cell activity and HIV immunopathogenesis.