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Background. To investigate the potential immunostimulatory effect of interleukin (IL) 2 as a human immunodeficiency virus type 1 (HIV-1) vaccine adjuvant, we conducted a study of a plasmid coding for a fusion protein of IL-2 and immunoglobulin (IL-2/Ig). Methods. This phase I trial evaluated an HIV-1 DNA vaccine with the plasmid cytokine adjuvant (IL-2/Ig) in 70 HIV-negative adults. Subjects received placebo (group C), adjuvant alone (group A), vaccine alone (group D), increasing doses of adjuvant concurrent with vaccine (groups T1-T4), or adjuvant given 2 days after vaccine (group T5). Results. No significant differences in adverse events were observed between treatment groups. Cellular immune responses to envelope protein EnvA peptides were detected by interferon (IFN) &ggr; and IL-2 enzymelinked immunospot (ELISPOT) assays in 50% and 40% of subjects, respectively, in T4, and in 100% and 80% in T5. The median responses for groups T4 and T5, respectively, were 90 and 193 spot-forming cells (SFCs)/106 peripheral blood mononuclear cells (P = .004; T4 vs T5) for the IL-2 ELISPOT assay and 103 and 380 SFCs/106 PBMCs (P = .003; T4 vs T5) for the IFN-&ggr; ELISPOT assay. A trend to more durable cellular immune responses in T5 was observed at 1 year (T5 vs T4/D; P = .07). Higher anti-Env antibody responses were detected with T5 than with T4. Conclusions. Plasmid IL-2/Ig significantly increased immune responses when administered 2 days after the DNA vaccine, compared with simultaneous administration. These observations have important implications for the development of cytokine augmentation strategies. [ABSTRACT FROM AUTHOR]

Background. We conducted a clinical trial of the safety and immunogenicity of modified vaccinia Ankara (MVA) to examine the effects of dose and route of administration. Methods. Seventy-two healthy, vaccinia virus-naive subjects received 1 of 6 regimens of MVA (ACAM3000) or placebo consisting of 2 administrations given 1 month apart. Results. MVA was generally well tolerated at all dose levels and by all routes. More pronounced local reactogenicity was seen with the intradermal and subcutaneous routes than with intramuscular administration. Binding antibodies to whole virus and neutralizing antibodies to the intracellular mature virion and extracellular enveloped virion forms of vaccinia virus were elicited by all routes of MVA administration and were greater for the higher dose by each route. Similar levels of neutralizing antibodies were seen at a 10-fold-lower dose given intradermally ( median 1 × 107 tissue culture infective doses [TCID50]), compared with responses after 1 × 108 TCID50 given intramuscularly or subcutaneously. T cell immune responses to vaccinia virus were detected by an interferon g enzyme-linked immunospot assay but had no clear relationship to dose or route. Conclusions. These data suggest that intradermal immunization with MVA provides a dose-sparing effect by eliciting antibody responses similar in magnitude and kinetics to those elicited by the intramuscular or subcutaneous routes but at a 10-fold-lower dose. [ABSTRACT FROM AUTHOR]

Background: Additional forms of pre-exposure prophylaxis are needed to prevent HIV-1 infection. 3BNC117 and 10–1074 are broadly neutralizing anti-HIV-1 antibodies that target non-overlapping epitopes on the HIV-1 envelope. We investigated the safety, tolerability, pharmacokinetics, and immunogenicity of the intravenous administration of the combination of 3BNC117 and 10–1074 in healthy adults. Methods: This randomized, double-blind, placebo-controlled, single center, phase 1 study enrolled healthy adults aged 18–65 years to receive one infusion of 3BNC117 immediately followed by 10–1074 at 10 mg/kg, three infusions of 3BNC117 followed by 10–1074 at 3 mg/kg or 10 mg/kg every 8 weeks, or placebo infusions. The primary outcomes were safety and pharmacokinetics. This trial is registered with ClinicalTrials.gov, number NCT02824536. Findings: Twenty-four participants were enrolled in a 3:1 ratio to receive the study products or placebo. The combination of 3BNC117 and 10–1074 was safe and generally well tolerated. There were no serious adverse events considered related to the infusions. The mean elimination half-lives of 3BNC117 and 10–1074 were 16.4 ± 4.6 days and 23.0 ± 5.4 days, respectively, similar to what was observed in previous studies in which each antibody was administered alone. Anti-drug antibody responses were rare and without evidence of related adverse events or impact on elimination kinetics. Interpretation: Single and repeated doses of the combination of 3BNC117 and 10–1074 were well tolerated in healthy adults. These data support the further development of the combination of 3BNC117 and 10–1074 as a long-acting injectable form of pre-exposure prophylaxis for the prevention of HIV-1 infection. [ABSTRACT FROM AUTHOR]

Background: VRC01 is an HIV-1 CD4 binding site broadly neutralizing antibody (bnAb) that is active against a broad range of HIV-1 primary isolates in vitro and protects against simian-human immunodeficiency virus (SHIV) when delivered parenterally to nonhuman primates. It has been shown to be safe and well tolerated after short-term administration in humans; however, its clinical and functional activity after longer-term administration has not been previously assessed.Methods and Findings: HIV Vaccine Trials Network (HVTN) 104 was designed to evaluate the safety and tolerability of multiple doses of VRC01 administered either subcutaneously or by intravenous (IV) infusion and to assess the pharmacokinetics and in vitro immunologic activity of the different dosing regimens. Additionally, this study aimed to assess the effect that the human body has on the functional activities of VRC01 as measured by several in vitro assays. Eighty-eight healthy, HIV-uninfected, low-risk participants were enrolled in 6 United States clinical research sites affiliated with the HVTN between September 9, 2014, and July 15, 2015. The median age of enrollees was 27 years (range, 18-50); 52% were White (non-Hispanic), 25% identified as Black (non-Hispanic), 11% were Hispanic, and 11% were non-Hispanic people of diverse origins. Participants were randomized to receive the following: a 40 mg/kg IV VRC01 loading dose followed by five 20 mg/kg IV VRC01 doses every 4 weeks (treatment group 1 [T1], n = 20); eleven 5 mg/kg subcutaneous (SC) VRC01 (treatment group 3 [T3], n = 20); placebo (placebo group 3 [P3], n = 4) doses every 2 weeks; or three 40 mg/kg IV VRC01 doses every 8 weeks (treatment group 2 [T2], n = 20). Treatment groups T4 and T5 (n = 12 each) received three 10 or 30 mg/kg IV VRC01 doses every 8 weeks, respectively. Participants were followed for 32 weeks after their first VRC01 administration and received a total of 249 IV infusions and 208 SC injections, with no serious adverse events, dose-limiting toxicities, nor evidence for anti-VRC01 antibodies observed. Serum VRC01 levels were detected through 12 weeks after final administration in all participants who received all scheduled doses. Mean peak serum VRC01 levels of 1,177 μg/ml (95% CI: 1,033, 1,340) and 420 μg/ml (95% CI: 356, 494) were achieved 1 hour after the IV infusion series of 30 mg/kg and 10 mg/kg doses, respectively. Mean trough levels at week 24 in the IV infusion series of 30 mg/kg and 10 mg/kg doses, respectively, were 16 μg/ml (95% CI: 10, 27) and 6 μg/ml (95% CI: 5, 9) levels, which neutralize a majority of circulating strains in vitro (50% inhibitory concentration [IC50] > 5 μg/ml). Post-infusion/injection serum VRC01 retained expected functional activity (virus neutralization, antibody-dependent cellular cytotoxicity, phagocytosis, and virion capture). The limitations of this study include the relatively small sample size of each VRC01 administration regimen and missing data from participants who were unable to complete all study visits.Conclusions: VRC01 administered as either an IV infusion (10-40 mg/kg) given monthly or bimonthly, or as an SC injection (5 mg/kg) every 2 weeks, was found to be safe and well tolerated. In addition to maintaining drug concentrations consistent with neutralization of the majority of tested HIV strains, VRC01 concentrations from participants' sera were found to avidly capture HIV virions and to mediate antibody-dependent cellular phagocytosis, suggesting a range of anti-HIV immunological activities, warranting further clinical trials.Trial Registration: Clinical Trials Registration: NCT02165267. [ABSTRACT FROM AUTHOR]

Background. Diagnosis of invasive fungal disease (IFD) is challenging, and it remains a significant cause of morbidity and mortality in immunocompromised patients. The (1r3)-b-D-glucan (BG) assay may be a useful adjunct, but its diagnostic performance is not well characterized. Methods. We retrospectively assessed the diagnostic indices of the BG assay in patients at risk of IFD who had a compatible clinical syndrome for the diagnosis of IFD a week after initial BG testing and at the end of the hospitalization associated with the first BG value. Patients with IFD were classified according to current European Organization for Research and Treatment of Cancer-Mycoses Study Group criteria, independent of BG results. Results. A total of 1308 BG assays were performed for 871 patients. One hundred twelve proven or probable IFD cases were diagnosed within 1 week after initial testing, and 116 cases were diagnosed by the end of hospitalization. Sensitivity of an initial BG level ⩾80 pg/mL for IFD at 1 week was 0.64 (95% confidence interval [CI], 0.55-0.73), specificity was 0.84 (95% CI, 0.81-0.86), the positive likelihood ratio was 3.93 (95% CI, 2.94-5.26), and the negative likelihood ratio was 0.43 (95% CI, 0.31-0.59). Albumin, intravenous immunoglobulin, and hemodialysis were associated with elevated BG levels in patients without IFD (odds ratio, 4.78; 95% CI, 2.59- 8.80). After excluding patients with these factors, specificity and the positive likelihood ratio of an initial BG level ⩾80 pg/mL increased slightly. Empirical systemic antifungal treatment did not reduce overall BG sensitivity. Sensitivity was slightly lower among patients with hematologic malignancy or stem cell transplantation. Consideration of BG results would have increased the diagnostic certainty to probable in 54% of possible IFD cases. Conclusions. BG level appears to be a fair diagnostic adjunct for IFD in patients with appropriate pretest probability and a suggestive clinical syndrome, especially when checked serially in patients not receiving factors associated with an elevated BG level in the absence of IFD. [ABSTRACT FROM AUTHOR]

The article presents a phase 2 trial study which aims to determine the performance of a canarypox vaccine candidate administered with rgp120 subunit protein for a trial to define a correlate of efficacy. The study measured the HIV-specific antibody responses by enzyme-linked immunoassay and neutralizing activity. The results revealed that HIV specific antibody cytotoxic T lymphocyte was insufficient to qualify the regimen for a subsequent trial.

Background. Alemtuzumab is an emerging therapy for refractory lymphoproliferative disorders. The associated long-term risks of infection remain poorly defined. Methods. From July 2001 through December 2003, all patients who received alemtuzumab for the treatment of lymphoproliferative disorders at 1 institution underwent a retrospective evaluation to document infectious complications until death or end of follow-up in October 2004. Alemtuzumab recipients who underwent allogeneic hematopoietic stem cell transplantation were compared with a concurrent cohort who also underwent allogeneic hematopoietic stem cell transplantation but did not receive alemtuzumab. Results. Twenty-seven patients were identified (21 with chronic lymphocytic leukemia and 6 with plasma cell disorders). The overall mortality was 37%, with 7 of 10 deaths being related to infection. Significant opportunistic infections occurred in 9 patients (43%) with chronic lymphocytic leukemia, including cytomegalovirus, progressive multifocal leukoencephalopathy, adenovirus, toxoplasmosis, and acanthamaebiasis. Thirty nonopportunistic infections in 22 patients (82%) were also identified. The 3 deaths related to nonopportunistic infections all involved Enterococcus species bacteremia. When compared with a concurrent chronic lymphocytic leukemia cohort that underwent allogeneic hematopoietic stem cell transplantation, alemtuzumab recipients had an incidence of cytomegalovirus reactivation of 66.7% (6 of 9 patients), compared with 37% in the non-alemtuzumab group (10 of 27 patients; P = .15), and an incidence of post-transplant opportunistic infections (excluding herpesviruses) of 44.4% (compared with 29.6% in the non-alemtuzumab group; P = .41). Conclusions. Despite the use of herpesvirus and Pneumocystis pneumonia prophylaxis, serious infectious complications occur in patients receiving alemtuzumab for lymphoproliferative disorders. Infectious complications are more varied and diverse in patients receiving alemtuzumab than has been reported in trials to date. [ABSTRACT FROM AUTHOR]

A recent clinical trial of a T-cell-based AIDS vaccine delivered with recombinant adenovirus type 5 (rAd5) vectors showed no efficacy in lowering viral load and was associated with increased risk of human immunodeficiency virus type 1 (HIV-1) infection. Preexisting immunity to Ad5 in humans could therefore affect both immunogenicity and vaccine efficacy. We hypothesized that vaccine-induced immunity is differentially affected, depending on whether subjects were exposed to Ad5 by natural infection or by vaccination. Serum samples from vaccine trial subjects receiving a DNA/rAd5 AIDS vaccine with or without prior immunity to Ad5 were examined for the specificity of their Ad5 neutralizing antibodies and their effect on HIV-1 immune responses. Here, we report that rAd5 neutralizing antibodies were directed to different components of the virion, depending on whether they were elicited by natural infection or vaccination in HIV vaccine trial subjects. Neutralizing antibodies elicited by natural infection were directed largely to the Ad5 fiber, while exposure to rAd5 through vaccination elicited antibodies primarily to capsid proteins other than fiber. Notably, preexisting immunity to Ad5 fiber from natural infection significantly reduced the CD4 and CD8 cell responses to HIV Gag after DNA/rAd5 vaccination. The specificity of Ad5 neutralizing antibodies therefore differs depending on the route of exposure, and natural Ad5 infection compromises Ad5 vaccine-induced immunity to weak immunogens, such as HIV-1 Gag. These results have implications for future AIDS vaccine trials and the design of next-generation gene-based vaccine vectors. [ABSTRACT FROM AUTHOR]