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1.  Specificity and 6-Month Durability of Immune Responses Induced by DNA and Recombinant Modified Vaccinia Ankara Vaccines Expressing HIV-1 Virus-Like Particles 
Background. Clade B DNA and recombinant modified vaccinia Ankara (MVA) vaccines producing virus-like particles displaying trimeric membrane-bound envelope glycoprotein (Env) were tested in a phase 2a trial in human immunodeficiency virus (HIV)–uninfected adults for safety, immunogenicity, and 6-month durability of immune responses.
Methods. A total of 299 individuals received 2 doses of JS7 DNA vaccine and 2 doses of MVA/HIV62B at 0, 2, 4, and 6 months, respectively (the DDMM regimen); 3 doses of MVA/HIV62B at 0, 2, and 6 months (the MMM regimen); or placebo injections.
Results. At peak response, 93.2% of the DDMM group and 98.4% of the MMM group had binding antibodies for Env. These binding antibodies were more frequent and of higher magnitude for the transmembrane subunit (gp41) than the receptor-binding subunit (gp120) of Env. For both regimens, response rates were higher for CD4+ T cells (66.4% in the DDMM group and 43.1% in the MMM group) than for CD8+ T cells (21.8% in the DDMM group and 14.9% in the MMM group). Responding CD4+ and CD8+ T cells were biased toward Gag, and >70% produced 2 or 3 of the 4 cytokines evaluated (ie, interferon γ, interleukin 2, tumor necrosis factor α, and granzyme B). Six months after vaccination, the magnitudes of antibodies and T-cell responses had decreased by <3-fold.
Conclusions. DDMM and MMM vaccinations with virus-like particle–expressing immunogens elicited durable antibody and T-cell responses.
PMCID: PMC4072895  PMID: 24403557
HIV/AIDS; vaccines; clinical trial; T cells; antibodies; DNA; recombinant MVA
2.  Intentions to use pre-exposure prophylaxis among current phase 2B preventive HIV-1 vaccine efficacy trial participants 
In November 2010, the iPrEx study reported that pre-exposure prophylaxis (PrEP) with daily tenofovir disoproxil fumarate/emtricitabine reduced HIV infections by 44% among men who have sex with men and subsequent trials corroborated efficacy among heterosexual men and women. During regularly scheduled follow-up visits from January-March 2011, participants in an ongoing phase 2b vaccine efficacy trial completed an anonymous web survey about PrEP. Among 376 respondents, 17% reported they were very likely to use PrEP in the next year. Non-white participants were more likely to use PrEP. Among those with some level of interest, intent to use PrEP was greatest if the drug were available through the clinical trial or health insurance. Most (91%) believed taking PrEP would not change their willingness to stay in the vaccine trial and few thought it would affect recruitment. As key stakeholders, currently enrolled trial participants can offer vital input about emerging prevention technologies that may affect the design of future HIV vaccine and non-vaccine prevention trials.
PMCID: PMC3714219  PMID: 23614998
clinical trials; HIV vaccines; pre-exposure prophylaxis; good participatory practice; HIV prevention
3.  Feasibility of identifying a cohort of US women at high risk for HIV infection for HIV vaccine efficacy trials: Longitudinal results of HVTN 906 
Identifying cohorts of US women with HIV infection rates sufficient for inclusion in vaccine efficacy trials has been challenging. Using geography and sexual network characteristics to inform recruitment strategies, HVTN 906 determined the feasibility of recruiting a cohort of women at high risk for HIV acquisition.
HIV uninfected women who reported unprotected sex in the prior six months, resided or engaged in risk behavior in local geographical high-risk pockets and/or had a male partner who had been incarcerated, injected drugs or had concurrent partners were eligible. Behavioral risk assessment, HIV counseling and testing and pregnancy testing were done at baseline, 6, 12 and 18 months.
Among 799 women, 71% were from local high-risk pockets and had high-risk male partners. Median age was 37 years; 79% were Black; 15% Latina. Over half (55%) reported a new partner in the prior six months, 57% reported a male partner who had concurrent female sexual partners and 37% reported a male partner who had been incarcerated. Retention at 18 months was 79.5%. Annual pregnancy incidence was 12%. Annual HIV incidence was 0.31% (95% CI: 0.06, 0.91). Risk behaviors decreased between screening and six months with smaller changes thereafter.
This cohort of women recruited using new strategies based on geography and sexual network characteristics did not have an HIV incidence high enough for HIV vaccine efficacy trials, despite high baseline levels of risk and a high pregnancy rate. New strategies to identify cohorts of US women for efficacy trials are needed.
PMCID: PMC3671573  PMID: 23446497
HIV vaccine trials; United States women; heterosexual transmission
4.  Recruitment of Caribbean female commercial sex workers at high risk of HIV infection 
To evaluate novel eligibility criteria and outreach methods to identify and recruit women at high risk of HIV-1 infection in the Caribbean.
A prospective cohort study was conducted in 2009–2012 among 799 female commercial sex workers in the Dominican Republic, Haiti, and Puerto Rico. Minimum eligibility criteria included exchange of sex for goods, services, or money in the previous 6 months and unprotected vaginal or anal sex with a man in the previous 6 months. Sites used local epidemiology to develop more stringent eligibility criteria and recruitment strategies. Participants were asked questions about HIV/AIDS and their level of concern about participating in an HIV vaccine trial. Logistic regression modeling was used to assess predictors of prevalent HIV infection and willingness to participate in a future HIV vaccine study.
HIV prevalence at screening was 4.6%. Crack cocaine use [odds ratio (OR) = 4.2, 95% confidence interval (CI) (1.8–9.0)] was associated with and having sex with clients in a hotel or motel [OR = 0.5, CI (0.3–1.0)] was inversely associated with HIV infection. A total of 88.9% of enrolled women were definitely or probably willing to participate in a future HIV vaccine trial.
This study indicated that local eligibility criteria and recruitment methods can be developed to identify and recruit commercial sex workers with higher HIV prevalence than the general population who express willingness to join an HIV vaccine trial.
PMCID: PMC4008335  PMID: 24096973
HIV infection; Acquired Immunodeficiency Syndrome; vaccine trial; commercial sex workers; Caribbean; Dominican Republic; Haiti; Puerto Rico
5.  Recruitment of urban US women at risk for HIV infection and willingness to participate in future HIV vaccine trials 
AIDS and behavior  2013;17(2):760-772.
Enrollment of US women with sufficient risk of HIV infection into HIV vaccine efficacy trials has proved challenging. A cohort of 799 HIV-negative women, aged 18-45, recruited from three US cities was enrolled to assess recruitment strategies based on geographic risk pockets, social and sexual networks and occurrence of sexual concurrency and to assess HIV seroincidence during follow-up (to be reported later). Among enrolled women, 90% lived or engaged in risk behaviors within a local risk pocket, 64% had a male partner who had concurrent partners and 50% had a male partner who had been recently incarcerated. Nearly half (46%) were recruited through peer referral. At enrollment, 86% of women said they were willing to participate in a vaccine efficacy trial. Results indicate that participant and partner risk behaviors combined with a peer referral recruitment strategy may best identify an at-risk cohort willing to participate in future trials.
PMCID: PMC3562410  PMID: 23090677
HIV vaccine trial preparedness; United States women; peer referral; respondent driven sampling; sexual concurrency; willingness to participate
6.  Veterans Aging Cohort Study (VACS) 
Medical care  2006;44(8 Suppl 2):S13-S24.
The Veterans Aging Cohort Study (VACS) is a study of human immunodeficiency virus (HIV) infected and uninfected patients seen in infectious disease and general medical clinics. VACS includes the earlier 3 and 5 site studies (VACS 3 and VACS 5) as well as the ongoing 8 site study.
We sought to provide background and context for analyses based upon VACS data, including study design and rationale as well as its basic protocol and the baseline characteristics of the enrolled sample.
Research Design
We undertook a prospectively consented multisite observational study of veterans in care with and without HIV infection.
Data were derived from patient and provider self report, telephone interviews, blood and DNA samples, focus groups, and full access to the national VA “paperless” electronic medical record system.
More than 7200 veterans have been enrolled in at least one of the studies. The 8 site study (VACS) has enrolled 2979 HIV-infected and 3019 HIV-uninfected age–race–site matched comparators and has achieved stratified enrollment targets for race/ethnicity and age and 99% of its total target enrollment as of October 30, 2005. Participants in VACS are similar to other veterans receiving care within the VA. VACS participants are older and more predominantly black than those reported by the Centers for Disease Control.
VACS has assembled a rich, in-depth, and representative sample of veterans in care with and without HIV infection to conduct longitudinal analyses of questions concerning the association between alcohol use and related comorbid and AIDS-defining conditions.
PMCID: PMC3049942  PMID: 16849964
HIV/AIDS; alcohol; aging veterans; data management/research design

Results 1-6 (6)