Daily Oral HIV Pre-exposure Prophylaxis Among Young Men Who Have Sex With Men in the United States: Cost-saving at Generic Drug Price.

BACKGROUND: Adherence and retention concerns raise questions about the effectiveness and cost-effectiveness of oral HIV pre-exposure prophylaxis (PrEP) in young men who have sex with men (YMSM). METHODS: Using an adolescent-focused simulation model, we compared annual HIV screening alone with tenofovir disoproxil fumarate/emtricitabine-based oral PrEP with every 3-month HIV screening in YMSM (aged 15-24) at increased risk of HIV. Data derived from published sources included: age-stratified HIV incidence/100 person-years (PY) on- or off-PrEP (0.6-10.1 or 0.4-6.4), PrEP retention at 6 years (28%), transmissions by HIV RNA level (0.0-78.4/100PY) and annual costs of antiretroviral therapy ($32 000-69 000), HIV care ($3100-34 600), and PrEP program/generic drug ($900/360). Outcomes included transmissions (percent of cohort infected), quality-adjusted life-years (QALYs), costs ($), and incremental cost-effectiveness ratios ($/QALY). We explored the sensitivity of findings to variation in HIV incidence and drug prices. RESULTS: Compared with annual screening alone, PrEP would increase QALYs (9.58 to 9.67), reduce new infections (37% to 30%), and decrease costs (by $5000) over 10 years. PrEP would remain cost-saving for HIV incidence off-PrEP ≥5.1/100PY or annual PrEP price ≤$1200. Over a lifetime horizon, PrEP would be cost-saving for HIV incidence off-PrEP ≥1.0/100PY, across all retention assumptions examined. PrEP would not be cost-effective at HIV incidence ≤0.1/100PY, regardless of drug price, due to programmatic costs. CONCLUSIONS: In US YMSM at increased risk of HIV, generic oral PrEP and every-3-month screening would be cost-saving compared with annual screening alone, even with high discontinuation and low adherence, over a range of HIV incidences.

Cost-effectiveness of Frequent HIV Screening Among High-risk Young Men Who Have Sex With Men in the United States.

BACKGROUND: Of new HIV infections in the US, 20% occur among young men who have sex with men (YMSM, ages 13-24), but >50% of YMSM with HIV are unaware of their status. Using Adolescent Medicine Trials Network for HIV/AIDS Interventions (ATN) data, we projected the clinical benefit and cost-effectiveness of frequent HIV screening among high-risk YMSM from age 15. METHODS: Using a mathematical simulation, we examined 3 screening strategies: Yearly, 6-monthly, and 3-monthly, each in addition to the Status quo (SQ, 0.7-10.3% screened/year, stratified by age). We used published data (YMSM-specific when available) including: HIV incidences (0.91-6.41/100PY); screen acceptance (80%), linkage-to-care/antiretroviral therapy (ART) initiation (76%), HIV transmission (0.3-86.1/100PY, by HIV RNA), monthly ART costs ($2290-$3780), and HIV per-screen costs ($38). Projected outcomes included CD4 count at diagnosis, primary HIV transmissions from ages 15-30, quality-adjusted life expectancy, costs, and incremental cost-effectiveness ratios (ICERs, $/quality-adjusted life-year saved [QALY]; threshold ≤$100 000/QALY). RESULTS: Compared to SQ, all strategies increased projected CD4 at diagnosis (296 to 477-515 cells/µL) and quality-adjusted life expectancy from age 15 (44.4 to 48.3-48.7 years) among YMSM acquiring HIV. Compared to SQ, all strategies increased discounted lifetime cost for the entire population ($170 800 to $178 100-$185 000/person). Screening 3-monthly was cost-effective (ICER: $4500/QALY) compared to SQ and reduced primary transmissions through age 30 by 40%. Results were most sensitive to transmission rates; excluding the impact of transmissions, screening Yearly was ≤$100 000/QALY (ICER: $70 900/QALY). CONCLUSIONS: For high-risk YMSM in the US, HIV screening 3-monthly compared to less frequent screening will improve clinical outcomes and be cost-effective.

High Prevalence of Anal High-Grade Squamous Intraepithelial Lesions, and Prevention Through Human Papillomavirus Vaccination, in Young Men Who Have Sex With Men Living With Human Immunodeficiency Virus.

BACKGROUND: Men who have sex with men (MSM) are at high risk for human papillomavirus (HPV)-related anal cancer. Little is known about the prevalence of low-grade squamous intraepithelial lesions (LSILs) and the anal cancer precursor, high-grade squamous intraepithelial lesions (HSILs), among young MSM with HIV (MSMLWH). HPV vaccination is recommended in this group, but its safety, immunogenicity, and protection against vaccine-type HPV infection and associated LSILs/HSILs have not been studied. METHODS: Two hundred and sixty MSMLWH aged 18-26 years were screened at 17 US sites for a clinical trial of the quadrivalent (HPV6,11,16,18) HPV (qHPV) vaccine. Those without HSILs were vaccinated at 0, 2, and 6 months. Cytology, high-resolution anoscopy with biopsies of lesions, serology, and HPV testing of the mouth/penis/scrotum/anus/perianus were performed at screening/month 0 and months 7, 12, and 24. RESULTS: Among 260 MSMLWH screened, the most common reason for exclusion was detection of HSILs in 88/260 (34%). 144 MSMLWH were enrolled. 47% of enrollees were previously exposed to HPV16. No incident qHPV type-associated anal LSILs/HSILs were detected among men naive to that type, compared with 11.1, 2.2, 4.5, and 2.8 cases/100 person-years for HPV6,11,16,18-associated LSILs/HSILs, respectively, among those previously exposed to that type. qHPV was immunogenic and safe with no vaccine-associated serious adverse events. CONCLUSIONS: 18-26-year-old MSMLWH naive to qHPV vaccine types were protected against incident qHPV type-associated LSILs/HSILs. Given their high prevalence of HSILs, there is an urgent need to vaccinate young MSMLWH before exposure to vaccine HPV types, before initiating sexual activity, and to perform catch-up vaccination.

Changes in Bone Mass After Discontinuation of Preexposure Prophylaxis With Tenofovir Disoproxil Fumarate/Emtricitabine in Young Men Who Have Sex With Men: Extension Phase Results of Adolescent Trials Network Protocols 110 and 113.

Human immunodeficiency virus-seronegative men aged 15-22 years who lost bone mineral density (BMD) during tenofovir disoproxil fumarate/emtricitabine preexposure prophylaxis (PrEP) showed BMD recovery 48 weeks following PrEP discontinuation. Lumbar spine and whole body BMD z-scores remained below baseline 48 weeks off PrEP in participants aged 15-19 years. Clinical Trials Registration. NCT01772823 (ATN 110) and NCT01769456 (ATN 113).

Prior incarceration associated with missed HIV care visits among young people living with HIV in the US.

Maintenance in HIV care is important to achieve optimal personal health and HIV viral load suppression for young people living with HIV (PLWH). We assessed the relationship between incarceration and missed visits in a longitudinal data cohort of PLWH (n = 910), ages 12-24, from 14 adolescent trial network sites across the US. The time from study entry to missed visits was modeled using Cox proportional hazards models. The cohort was mostly male (78%) and African American (75%) with a median age of 22. Prior incarceration had been experienced by 39% of the cohort, with a median number of times incarcerated of 2 (IQR: 1-3). The crude and adjusted hazard ratios for missed HIV care visits comparing those with incarceration histories to those without were 1.27 (95% CI: 1.06, 1.54) and 1.53 (95% CI: 1.26, 1.86). Among those returning to care, HIV viral loads were more likely to be unsuppressed among those with incarceration history compared to those without (RR: 1.28, 95% CI: 0.95, 1.74). This association was attenuated to the null after adjustment for suppression of viral load prior to the missed visit. Young PLWH with incarceration histories are at higher risk of missing HIV care visits.

Racial disparities and factors associated with prescription for smoking cessation medications among smokers receiving routine clinical care for HIV.

Factors associated with prescription of smoking cessation medication (SCM), including the impact of race, have not been well described among a large population of people living with HIV (PLWH) engaged in routine clinical care. Our study investigated whether there are racial differences between African-American and White PLWH regarding SCM prescription and sought to identify other factors associated with these prescriptions at a large HIV clinic in the Southeastern United States. Among 1899 smokers, 38.8% of those prescribed SCMs were African-American and 61.2% were White. Factors associated with lower odds of SCM prescription included African-American race (AOR, 0.63 [95% CI: 0.47, 0.84]) or transferring care from another HIV provider during the study period (AOR, 0.63 [95% CI: 0.43, 0.91]). Whereas major depression (AOR, 1.54 [95% CI: 1.10, 2.15]), anxiety symptoms (AOR, 1.43 [95% CI: 1.05, 1.94]), and heavy smoking (>20 cigarettes/day) (OR, 3.50 [95% CI: 2.11, 5.98]) were associated with increased likelihood of SCM prescription. There were racial disparities in the prescription of SCM in African Americans with HIV. These findings underscore the need to increase pharmacotherapy use among African Americans to improve smoking cessation outcomes across racial groups among PLWH.

Predictors of smoking cessation among people living with HIV receiving routine clinical care.

People living with HIV (PLWH) have a higher prevalence of smoking and are less likely to quit smoking than the general population. Few studies involving a large sample of PLWH receiving routine care have evaluated factors associated with smoking cessation. This retrospective longitudinal cohort study evaluated factors associated with smoking cessation among PLWH from 2007 to 2018. Of 1,714 PLWH smokers included in the study, 27.6% reported quitting smoking. Suppressed plasma HIV-1 RNA (<200 copies/ml) was significantly associated with an increased likelihood of smoking cessation (HRadjusted = 1.27, 95% CI [1.03, 1.58]); whereas age/10 year increments (HRadjusted = 0.12, 95% CI [0.04, 0.38]), greater length of care at the HIV clinic (HRadjusted = 0.97, 95% CI [0.94, 0.99]), lack of insurance (HRadjusted = 0.77, 95% CI [0.61, 0.99]) or having public insurance (HRadjusted = 0.74, 95% CI [0.55, 0.97)]), current substance use (HRadjusted = 0.66, 95% CI [0.43, 0.97]) and risk of developing alcohol use disorder (HRadjusted = 0.60, 95% CI [0.43, 0.84]) were associated with a reduced likelihood of quitting smoking. These findings underscore the importance of early smoking cessation intervention among PLWH. In addition, targeted smoking cessation intervention strategies are needed for groups at risk for being less likely to quit, including older patients, and those with alcohol and substance use disorders.

Mental health disorders and alcohol use are associated with increased likelihood of smoking relapse among people living with HIV attending routine clinical care.

BACKGROUND: People living with HIV (PLWH) have a high level of interest in quitting smoking, but only a small proportion have sustainable abstinence 6 months after cessation. Few investigations have focused on relapse to smoking among PLWH. In this investigation, we evaluated the prevalence of relapse after smoking cessation and the characteristics associated with smoking relapse using a retrospective, longitudinal cohort of PLWH during an eight-year observation. METHODS: All patients aged ≥19 years that reported current smoking during the study period and then reported not smoking on a subsequent tobacco use questionnaire (quitters) were eligible for the study. In addition, patients required at least one subsequent follow-up visit after quitting where smoking status was again reported to allow for assessment of relapse. A Cox proportional hazard model was fit to evaluate factors associated with smoking relapse in PLWH attending routine clinical care. RESULTS: Of the 473 patients who quit smoking in the study, 51% relapsed. In multivariable analysis, factors significantly associated with a higher likelihood of relapse were anxiety symptoms (HR = 1.55, 95% CI [1.11, 2.17]) and at-risk alcohol use (HR = 1.74, 95% CI [1.06, 2.85]), whereas antiretroviral therapy (ART) adherence (HR = 0.65, 95% CI [0.49, 0.99]) and longer time in care (HR = 0.94, 95% CI [0.91, 0.98]) were associated with a reduced likelihood of relapse after cessation. CONCLUSION: Our study underscores the high prevalence of smoking relapse that exists among PLWH after they quit smoking. Successful engagement in mental health care may enhance efforts to reduce relapse in the underserved populations of PLWH.

Comparison of Measures of Adherence to Human Immunodeficiency Virus Preexposure Prophylaxis Among Adolescent and Young Men Who Have Sex With Men in the United States.

Background: Young men-who-have-sex-with-men (MSM) are disproportionately impacted by human immunodeficiency virus (HIV). Preexposure prophylaxis (PrEP) could reduce HIV acquisition among youth, but suboptimal adherence threatens effectiveness. Optimal metrics of PrEP adherence among adolescents have remain undefined. Methods: The Adolescent Trials Network 110/113 studies provided daily oral PrEP with tenofovir (TFV) disoproxil fumarate/emtricitabine over 48 weeks to a diverse population of MSM (aged 15-22 years). Self-reported adherence was assessed and PrEP drug concentrations measured from hair and dried blood spot (DBS) samples; 23% of participants received Wisepill electronic monitoring devices. The average number of PrEP doses per week taken was estimated, and concordance between measures assessed. Results: Among 243 participants, hair samples were collected at 1186/1238 (96%) person-visits. The concordance of TFV levels in hair and TFV-diphosphate in DBS around thresholds consistent with taking ≥4 and 7 PrEP doses/week was high (76% and 80%). Hair and DBS concentrations correlated poorly with self-report and Wisepill metrics. Through week 12, 40%-60% of participants (by hair and DBS), ≤31% (Wisepill), and >85% (self-report) were estimated to have taken ≥4 PrEP doses/week (a threshold associated with protection among MSM). For all measures except self-report, adherence declined over time, with half of participants taking <2 doses/week by week 48. Conclusions: Among youth on PrEP, adherence waned over time. Self-report overestimated adherence, and use of Wisepill was limited. Hair collection was highly acceptable and provided similar interpretations to DBS. Incorporation of either metric in future PrEP studies among youth could identify suboptimal adherence and trigger interventions.

Vitamin D3 Supplementation Increases Spine Bone Mineral Density in Adolescents and Young Adults With Human Immunodeficiency Virus Infection Being Treated With Tenofovir Disoproxil Fumarate: A Randomized, Placebo-Controlled Trial.

Background: Tenofovir disoproxil fumarate (TDF) decreases bone mineral density (BMD). We hypothesized that vitamin D3 (VITD3) would increase BMD in youth receiving TDF. Methods: This was a randomized, double-blind, placebo-controlled trial of directly observed VITD3 vs placebo every 4 weeks for 48 weeks in youth aged 16-24 years with HIV, RNA load <200 copies/mL, taking TDF-containing combination antiretroviral therapy (TDF-cART) for ≥180 days. Participants (N = 214) received a daily multivitamin containing VITD3 400 IU and calcium 162 mg, plus monthly randomized VITD3 50000 IU (n = 109) or placebo (n = 105). Outcome was change from baseline to week 48 in lumbar spine BMD (LSBMD). Data presented are median (Q1, Q3). Results: Participants were aged 22.0 (21.0, 23.0) years, 84% were male, and 74% were black/African American. At baseline, 62% had 25-hydroxy vitamin D (25-OHD) <20 ng/mL. Multivitamin adherence was 49% (29%, 69%), and VITD3/placebo adherence 100% (100%, 100%). Vitamin D intake was 2020 (1914, 2168) and 284 (179, 394) IU/day, and serum 25-OHD concentration was 36.9 (30.5, 42.4) and 20.6 (14.4, 25.8) ng/mL at 48 weeks in VITD3 and placebo groups, respectively (P < .001). From baseline to week 48, LSBMD increased by 1.15% (-0.75% to 2.74%) in the VITD3 group (n = 99; P < .001) and 0.09% (-1.49% to 2.61%) in the placebo group (n = 89; P = .25), without between-group difference (P = .12). VITD3 group changes occurred with baseline 25-OHD <20 ng/mL (1.17% [-.82% to 2.90%]; P = .004) and ≥20 ng/mL (0.93% [-.26% to 2.15%]; P = .033). Conclusions: For youth taking TDF-cART, LSBMD increased through 48 weeks with VITD3 plus multivitamin, but not with placebo plus multivitamin, independent of baseline vitamin D status. Clinical Trials Registration: NCT01751646.

A cross-sectional study examining associations between substance use frequency, problematic use and STIs among youth living with HIV.

OBJECTIVES: This study sought to examine the prevalence of STIs and whether substance use frequency and/or problematic use-specifically alcohol, marijuana and other drugs-was associated with having an STI diagnosis among youth living with HIV (YLWH) METHODS: A sample of 823 YLWH were recruited at 14 adolescent HIV clinics through the Adolescent Medicine Trials Network for HIV Interventions. Study staff abstracted STI data from medical records for up to 26 weeks prior to participants' completing a cross-sectional survey including the ASSIST (Alcohol, Smoking and Substance Involvement Screening Test), which measures substance use frequency and consequences. RESULTS: Almost one-third of youth had been diagnosed with an STI (30.5%) at the time of their baseline assessment. In multivariable analyses, those who engaged in weekly or greater marijuana use (adjusted OR (AOR)=10.66, 95% CI: 4.39 to 25.87, P<0.001) had an increased odds of being diagnosed with an STI. Additionally, youth who met alcohol use criteria for moderate (AOR=5.23, 95% CI: 2.50 to 10.93, P<0.001) and high risk (AOR=6.53, 95% CI: 1.20 to 35.68, P<0.05) alcohol use had an increased odds of being diagnosed with an STI compared with low-risk alcohol users. CONCLUSIONS: Study findings underscore the need to investigate the role of greater frequency of marijuana use and problematic alcohol use in STI incidence among YLWH. Given the associations between both substance use frequency and problematic use in STI diagnoses among YLWH seen in HIV care settings, clinicians should use validated substance use screening tools which capture both frequencies and consequences in order to identify YLWH who may need further evaluation and treatment.

Tobacco Use and Sustained Viral Suppression in Youth Living with HIV.

Tobacco has been associated with worse HIV disease progression in adult samples of people living with HIV; however, studies have yet to examine these effects in youth living with HIV (YLWH). This study examined the association between tobacco smoking behaviors and sustained viral suppression among a sample of 820 YLWH who were recruited through the Adolescent Medicine Trials Network for HIV Interventions. Participants completed a cross-sectional survey and then staff abstracted viral suppression data from medical records for up to 26 weeks prior to enrollment. Overall, 20.4% of youth reported daily or almost daily tobacco use. In multivariable analyses, older age and daily or almost daily tobacco smoking, and ART adherence remained statistically significant in predicting sustained viral suppression over the study period. These findings underscore the need for tobacco screening and interventions in HIV care settings in order to identify youth in need of additional smoking cessation services.

Decline in Bone Mass With Tenofovir Disoproxil Fumarate/Emtricitabine Is Associated With Hormonal Changes in the Absence of Renal Impairment When Used by HIV-Uninfected Adolescent Boys and Young Men for HIV Preexposure Prophylaxis.

BACKGROUND: We aimed to define the relative importance of renal and endocrine changes in tenofovir disoproxil fumarate (TDF)-related bone toxicity. METHODS: In a study of daily TDF/emtricitabine (FTC) preexposure prophylaxis (PrEP) in human immunodeficiency virus (HIV)-uninfected young men who have sex with men, we measured changes from baseline in blood and urine markers of the parathyroid hormone (PTH)-vitamin D-fibroblast growth factor 23 (FGF23) axis, creatinine, and renal tubular reabsorption of phosphate (TRP). We explored the relationship of those variables to changes in bone mineral density (BMD). Tenofovir-diphosphate (TFV-DP) in red blood cells was used to categorize participants into high and low drug exposure groups. RESULTS: There were 101 participants, median age 20 years (range 15 to 22). Compared with low drug exposure, high-exposure participants showed increase from baseline in PTH and decline in FGF23 by study week 4, with no differences in creatinine, phosphate, or TRP. At 48 weeks, the median (interquartile range) percent decline in total hip BMD was greater in those with high- compared to low- exposure (-1.59 [2.77] vs +1.54 [3.34] %, respectively; P = .001); in high-exposure participants, this correlated with week 4 TFV-DP (inversely; r = -0.60, P = .002) and FGF23 (directly; r = 0.42; P = .039) but not other variables. CONCLUSIONS: These findings support the short-term renal safety of TDF/FTC PrEP in HIV-seronegative young men and suggest that endocrine disruption (PTH-FGF23) is a primary contributor to TDF-associated BMD decline in this age group. CLINICAL TRIALS REGISTRATION: NCT01769469.

Emtricitabine-Triphosphate in Dried Blood Spots as a Marker of Recent Dosing.

New objective measures of antiretroviral adherence are needed. We determined if emtricitabine triphosphate (FTC-TP) in dried blood spots (DBS) can be used as a marker of recent dosing with tenofovir disoproxil fumarate-emtricitabine (TDF-FTC). The half-life of FTC-TP was estimated in DBS samples obtained from an intensive pharmacokinetic (PK) study of coformulated TDF-FTC in HIV-negative and HIV-infected participants. The concordance of quantifiable FTC-TP in DBS with tenofovir (TFV)/FTC in plasma was evaluated by utilizing paired plasma-DBS samples from participants enrolled in 2 large preexposure prophylaxis (PrEP) open-label trials. The time to FTC-TP nondetectability after TDF-FTC dosing was evaluated utilizing DBS from HIV-negative participants enrolled in a directly observed therapy study of variable adherence to TDF-FTC. The mean (95% confidence interval [CI]) terminal half-life of FTC-TP in the PK study was 35 (23 to 47) h. A total of 143/163 (88%) samples obtained 0 to 48 h post-TDF-FTC dose had quantifiable FTC-TP in DBS, compared with 2/93 (2%) and 0/87 (0%) obtained >48 and >96 h postdose. In 746 paired plasma-DBS samples from 445 participants enrolled in PrEP trials, when both TFV/FTC in plasma were below the limit of quantification, FTC-TP was as well in 98.9% of the samples, and when either TFV or FTC in plasma was quantifiable, FTC-TP was as well in 90.5% of the samples. The half-life of FTC-TP in DBS is short relative to that of TFV-diphosphate (TFV-DP), making it a surrogate for TFV-FTC detection in plasma. FTC-TP can be quantified in DBS simultaneously with TFV-DP, which quantifies cumulative adherence to TDF-FTC. (The clinical trials discussed in this article have been registered at ClinicalTrials.gov under identifiers NCT01040091, NCT02022657, NCT00458393, NCT01772823, and NCT02012621.).

Antiretroviral treatment initiation does not differentially alter neurocognitive functioning over time in youth with behaviorally acquired HIV.

Although youth living with behaviorally acquired HIV (YLWH) are at risk for cognitive impairments, the relationship of impairments to HIV and potential to improve with antiretroviral therapy (ART) are unclear. This prospective observational study was designed to examine the impact of initiation and timing of ART on neurocognitive functioning in YLWH in the Adolescent Medicine Trials Network for HIV/AIDS Interventions. Treatment naïve YLWH age 18-24 completed baseline and four additional assessments of attention/working memory, complex executive, and motor functioning over 3 years. Group 1 co-enrolled in an early ART initiation study and initiated ART at enrollment CD4 >350 (n = 56); group 2 had CD4 >350 and were not initiating ART (n = 66); group 3 initiated ART with CD4 <350 (n = 59) per standard of care treatment guidelines at the time. Treatment was de-intensified to boosted protease inhibitor monotherapy at 48 weeks for those in group 1 with suppressed viral load. Covariates included demographic, behavioral, and medical history variables. Analyses used hierarchical linear modeling. All groups showed improved performance with peak at 96 weeks in all three functional domains. Trajectories of change were not significantly associated with treatment, timing of treatment initiation, or ART de-intensification. Demographic variables and comorbidities were associated with baseline functioning but did not directly interact with change over time. In conclusion, YLWH showed improvement in neurocognitive functioning over time that may be related to practice effects and nonspecific impact of study participation. Neither improvement nor decline in functioning was associated with timing of ART initiation or therapy de-intensification.

How we implemented an analytical support clinic to strengthen student research capacity in Zambia.

BACKGROUND: Research outputs in sub-Saharan Africa may be limited by a scarcity of clinical research expertise. In Zambia, clinical and biomedical postgraduate students are often delayed in graduation due to challenges in completing their research dissertations. We sought to strengthen institutional research capacity by supporting student and faculty researchers through weekly epidemiology and biostatistics clinics. METHODS: We instituted a weekly Analytical Support Clinic at the University of Zambia, School of Medicine. A combination of biostatisticians, clinical researchers and epidemiologists meet weekly with clients to address questions of proposal development, data management and analysis. Clinic sign-in sheets were reviewed. RESULTS: 109 students and faculty members accounted for 197 visits to the Clinic. Nearly all clients (107/109, 98.2%) were undergraduate or postgraduate students. Reasons for attending the Clinic were primarily for proposal development (46.7%) and data management/analysis (42.1%). The most common specific reasons for seeking help were data analysis and interpretation (36.5%), development of study design and research questions (26.9%) and sample size calculation (21.8%). CONCLUSIONS: The Analytical Support Clinic is an important vehicle for strengthening postgraduate research through one-on-one and small group demand-driven interactions. The clinic approach supplements mentorship from departmental supervisors, providing specific expertise and contextual teaching.

Immunogenicity and safety of the human papillomavirus 6, 11, 16, 18 vaccine in HIV-infected young women.

BACKGROUND: The objective of this study was to determine whether the 3-dose quadrivalent human papillomavirus (HPV) vaccine series (HPV-6, -11, -16, -18) is immunogenic and safe in young women infected with human immunodeficiency virus (HIV). METHODS: We enrolled 99 women aged 16-23 years in a phase 2, open-label, multicenter trial, conducted from 2008 to 2011 by the Adolescent Medicine Trials Network for HIV/AIDS Interventions. Outcome measures were immunogenicity 4 weeks after dose 3, measured by (1) geometric mean titers (GMTs) and (2) seroconversion rates for HPV-6, -11, -16, and -18, among those seronegative and HPV DNA negative for each type. Immune responses were compared to those of a historical comparison group of HIV-negative women (n = 267) using univariate methods. Clinical and laboratory adverse events were assessed after each dose. RESULTS: The mean age of subjects was 21.4 years; 80% were non-Hispanic black, 69 were not taking antiretroviral therapy (ART), and 30 were taking ART. No differences in GMTs were noted among participants taking ART vs the comparison group, but GMTs were lower in participants not taking ART vs the comparison group for HPV-16 (2393 vs 3892 milli-Merck units per milliliter [mMU/mL], P = .012) and HPV-18 (463 vs 801 mMU/mL, P = .003). Seroconversion rates were 100% for HPV-6, -11, -16, and -18 among participants taking ART. Rates ranged from 92.3% (for HPV-18) to 100.0% (for HPV-6) among participants not taking ART. One severe adverse event (fatigue) was noted. CONCLUSIONS: In a sample of HIV-infected women who were HPV DNA and HPV seronegative, immune responses to HPV vaccination were generally robust and the vaccine was well tolerated.

Association of higher plasma vitamin D binding protein and lower free calcitriol levels with tenofovir disoproxil fumarate use and plasma and intracellular tenofovir pharmacokinetics: cause of a functional vitamin D deficiency?

Tenofovir disoproxil fumarate (TDF) causes bone, endocrine, and renal changes by an unknown mechanism(s). Data are limited on tenofovir pharmacokinetics and these effects. Using baseline data from a multicenter study of HIV-infected youth on stable treatment with regimens containing TDF (n = 118) or lacking TDF (n = 85), we measured cross-sectional associations of TDF use with markers of renal function, vitamin D-calcium-parathyroid hormone balance, phosphate metabolism (tubular reabsorption of phosphate and fibroblast growth factor 23 [FGF23]), and bone turnover. Pharmacokinetic-pharmacodynamic associations with plasma tenofovir and intracellular tenofovir diphosphate concentrations were explored among those receiving TDF. The mean age was 20.9 (standard deviation [SD], 2.0) years; 63% were male; and 52% were African American. Compared to the no-TDF group, the TDF group showed lower mean estimated glomerular filtration rates and tubular reabsorption of phosphate, as well as higher parathyroid hormone and 1,25-dihydroxy vitamin D [1,25-OH(2)D] levels. The highest quintile of plasma tenofovir concentrations was associated with higher vitamin D binding protein, lower free 1,25-OH(2)D, higher 25-OH vitamin D, and higher serum calcium. The highest quintile of intracellular tenofovir diphosphate concentration was associated with lower FGF23. Higher plasma tenofovir concentrations were associated with higher vitamin D binding protein and lower free 1,25-OH(2)D, suggesting a functional vitamin D deficiency explaining TDF-associated increased parathyroid hormone. The finding of lower FGF23 accompanying higher intracellular tenofovir diphosphate suggests that different mechanisms mediate TDF-associated changes in phosphate handling. Separate pharmacokinetic properties may be associated with distinct TDF toxicities: tenofovir with parathyroid hormone and altered calcium balance and tenofovir diphosphate with hypophosphatemia and FGF23 regulation. (The clinical trial registration number for this study is NCT00490412 and is available online at http://clinicaltrials.gov/ct2/show/NCT00490412.).

Incident anal human papillomavirus and human papillomavirus-related sequelae in HIV-infected versus HIV-uninfected adolescents in the United States.

BACKGROUND: Little is known about the incidence of anal human papillomavirus (HPV) infection and related sequelae, as well as factors associated with these outcomes, among adolescents who are HIV infected versus HIV uninfected but at risk. METHODS: We analyzed the data from a multisite US study, the Reaching for Excellence in Adolescent Care and Health Project. Adolescents aged 12 to 18 years who were behaviorally HIV infected (n = 319) or HIV uninfected but at risk (n = 177) were recruited. Incidence rates for anal HPV, high-risk anal HPV, anogenital warts, and anal dysplasia were calculated using Poisson modeling. Factors associated with these outcomes were examined using Cox proportional hazards modeling. RESULTS: Mean age at entry was 16.8 years; mean (SD) follow-up time for detection of anal HPV was 22.4 (10.8) months. Most participants (76%) were female; 70% were black non-Hispanic. HIV-infected (vs. HIV-uninfected) women had a significantly higher incidence of anal HPV (30 vs. 14 per 100 person-years; P = 0.002), high-risk anal HPV (12 vs. 5.3 per 100 person-years; P = 0.04), and anogenital warts (6.7 vs. 1.6 per 100 person-years; P = 0.002) but not anal dysplasia. Although incidence rates were higher for these outcomes among HIV-infected versus HIV-uninfected men, the differences were not statistically significant. Among women, factors associated with anal HPV and related sequelae differed by HIV status and included biological, behavioral, and HIV-related factors. No factors were associated with outcomes in men. CONCLUSIONS: HIV-infected versus HIV-uninfected adolescent women had higher rates of anal HPV and anogenital warts. Because HIV-infected youth are at increased risk of these outcomes, enhanced HPV prevention efforts such as vaccination are warranted for this group.

Comprehension of a simplified assent form in a vaccine trial for adolescents.

INTRODUCTION: Future HIV vaccine efficacy trials with adolescents will need to ensure that participants comprehend study concepts in order to confer true informed assent. A Hepatitis B vaccine trial with adolescents offers valuable opportunity to test youth understanding of vaccine trial requirements in general. METHODS: Youth reviewed a simplified assent form with study investigators and then completed a comprehension questionnaire. Once enrolled, all youth were tested for HIV and confirmed to be HIV-negative. RESULTS: 123 youth completed the questionnaire (mean age=15 years; 63% male; 70% Hispanic). Overall, only 69 (56%) youth answered all six questions correctly. CONCLUSIONS: Youth enrolled in a Hepatitis B vaccine trial demonstrated variable comprehension of the study design and various methodological concepts, such as treatment group masking.